WO2008139167A2

WO2008139167A2 - Radiological quality assurance phantom

Info

Publication number: WO2008139167A2
Application number: PCT/GB2008/001620
Authority: WO
Inventors: Cameron Carpenter
Original assignee: Cameron Carpenter
Priority date: 2007-05-11
Filing date: 2008-05-09
Publication date: 2008-11-20
Also published as: GB0709069D0; GB2449113B; GB2449113A; WO2008139167A9

Abstract

The diagnostic test tool is designed to simultaneously compare and evaluate measurement accuracy on a wide range of radiological imaging apparatus. It enables comparison of known reference values of a test object against those values generated by manufacturer software image measurement programs commonly found on diagnostic viewing facilities. The tool can compare measurement accuracy across most radiological imaging platforms including digital subtraction angiography, computed tomography, magnetic resonance imaging, radio-fluoroscopy, and newer combination scanners. These can now be collectively compared and evaluated, along with manufacturer reporting software including multi-planar reconstruction, maximum intensity projection, and curved reconstructions. The construction of its cross-sectional modules will provide a reference diameter on each constructed image and will allow distance in the z-axis to be accurately referenced. Comparison of this reference value with what is measured at the reporting platform will give a measure of compliance / non-compliance of the imaging equipment with the reference.

Description

RADIOLOGICAL QUALITY ASSURANCE PHANTOM

FIELD OF THE INVENTION

The invention relates to a quality assurance phantom system for the calibration of radiological imaging apparatus involved in the diagnosis of diseases in patients. The universal imaging phantom allows an investigator to test and validate the measurement accuracy of 2-Dimensional and 3-Dimensional image measurement tools installed on medical imaging devices including digital subtraction angiography (DSA) and radio-fluoroscopic (RF) machines, computerised tomography (CT) and magnetic resonance imaging (MRI) scanners, nuclear (isotope) imaging (NI) scanners and computed radiography (CR) machines, digital image viewing stations that include diagnostic, clinical review, internet browser and teleradiology network or satellite transferred medical diagnostic image systems.

DESCRIPTION OF THE PRIOR ART

Radiological imaging systems have undergone an intensive phase of innovative development which is extensively documented by the designs, innovations and configurations classified as prior art. The performance of radiological devices, their generated images and the transfer of those images across digital networks are all calibrated and tested by phantoms and devices which when imaged by the respective modality generate image(s) that are representative, familiar and logical to the structure and configuration of the phantom. Systematic testing and measurement of the image(s) should produce measurement value(s) that fall within a range of expected and legally acceptable values which indicate that the imaging machine is operating within normal or acceptable levels of performance.

By way of example, U. S Pat.No. US 7,056,019 Bl published 6^th June 2006, to Hanson et al discloses a quality assurance phantom system for the testing of diagnostic machines in a safe and efficient manner. U.S Pat.Application. US 2005/0008126 Al published 13^th January 2005, to Juh et al discloses a phantom for evaluating accuracy of image registration software. European Patent Application EP 1 484 015 Al published 8^th December 2004, to Karasawa discloses a quality control phantom for testing verification of performance and invariance of a radiation imaging system. European Patent Application EP 1 062 912 Al published 27^th December 2000, to General Electric Company discloses modular interchangeable phantoms for multiple X-ray systems. U.S Pat.No. US 5,841,835 published 24^th November 1998, to Aufrichtig et al discloses apparatus and method for automatic monitoring and assessment of image quality in X-ray systems. U.S Pat No. 5,872,829 published 16* February 1999, to Wischmann et al discloses a method for the detection and correction of image distortions in medical imaging. U.S Pat. No. 5,481,587 published 2^nd January 1996, to Mazess discloses a radiographic phantom for vertebral morphometry.

The devices mentioned above in the prior art have provided a number of innovative designs and concepts, and by virtue of their own particular design features), configuration(s) and method(s) of use have fulfilled their desired function(s). It is nonetheless clear that each of these devices has not been designed to address the issue of how to validate the measurement accuracy of a non-linear structure such as a blood vessel which by its very nature displays a continuously varying degree of curvature along the entire length of the vessel, and where parametric value(s) of diameter, area, volume and length are difficult to determine as a result of the levels of planar variations in the x, y and z components of the image in each of the respective image(s).

A typical aneurysmal and tortuous blood vessel will exhibit high levels of positional deviation in x and y image co-ordinates of the image contained within the confines of a sectional image of defined area or field of view and thickness. Thinner sectional images will give the best accuracy of diameter measurement (s) of the vessel if viewed perpendicularly or perfectly end on. When the vessel end anatomically rotated or in the case where it is viewed in a slightly rotated plane of observation, such that the furthest end of the image eclipses with the nearest end of the vessel, it is likely that the measurement value(s) obtained will be over-estimated as a consequence of this.

Correspondingly, as the sectional thickness increases and the z-axis component reaches its maximum, the recorded thickness of the image of the blood vessel increases the over-estimation of the diameter, so it is good practice to measure the vessel diameter from two planes of view. In the case of estimation of length, the z-axis component is at its maximum, as is the case for the x and y axis components. The 3-Dimensional image display may be orientated into any position in space by the user and measurements may be performed using a range of specialised tools. These include maximum intensity projections (MIP' s), multi-planar reconstructions (MPR's) and curved reconstructions which allow reasonably accurate measurements to be made of non-linear structures that may lie in and out of a particular viewing plane of specified image thickness, but which also may be optimised in terms of its positioning and orientation and measured as a complete structural form. The technique and practice of using these volumetric tools has been largely successful as aids to diagnostic measurement(s), but tests performed using a prototype radiological phantom has indicated sizeable measurement anomalies of actual and interpreted values of diameter and length. The above cited patents and patent applications do not address the necessary requirement to evaluate the accuracy actually achieved when measuring highly curved or tortuous structures.

Imaging modalities are configured to operate within prescribed modes of operation for each type of scan performed. The universal imaging phantom consists of a range of modality specific radiological phantoms which can be used to test and examine the capability of a scanner to image, display and measure the generated image(s) and to provide accurate value(s) of diameter, area, volume and length. The length may be a straight line for which a 2-Dimensional measurement method will be straight forward and highly accurate, while the measurement method employed for a live which curves variably into all orthogonal planes will require use of a 3-Dimensional display and measurement tool which requires the outline of the object to be traced from an initial point of reference, along and throughout every contortion of the line progression to the end point of reference where the final distance value is generated by the software program of the measurement tool. The derived value is taken to be correct for all conditions of measurement. The universal imaging phantom enables by way of its alternative configuration, a means of evaluation not afforded by other quality assurance phantoms in that in one type of configuration provides images that when measured with the modality measurement tools of the scanner, generate value(s) of diameter, area, volume and length which are indicative of a high level of linear measurement accuracy achieved by the measurement tools of the scanner.

Conversely, the radiological phantom may be configured in an alternative way such that when the image(s) are displayed and measured, difficulties arise in visualising and displaying on the selected imaging modality the complete structural image of the modality specific radiological phantom, where obtaining an orientation of an image that when the points of reference are measured do not have a wide margin of variation or where it produces values of diameter, area, volume and length that match the parametric reference value(s) contained internally and externally on the phantom.

The universal imaging phantom consists of a plurality of modality specific radiological phantoms which are generally mounted on the fixing columns attached to the base frame. The base frame allows for multiple configurations of the modality specific tools so that the phantom may be tested on multiple imaging modalities. The image(s) of the modality specific radiological phantoms are designed to test both 2-Dimensional and 3-Dimensional image generation by the imaging modality where in the cases of 2-Dimensional images produced in digital subtraction angiography (DSA), radio-fluoroscopy (RF), computerised tomography (CT), magnetic resonance imaging (MRI), nuclear (isotope) imaging (NI) and computed radiography (CR), an indication of hardware performance of the selected image modality is obtained in its capability of registering an image and constructing and displaying it. Any distortions in an image may be indicated at this early stage by the presence of elongation or distortion of the designed reference structures contained in these modality specific radiological phantoms as additionally in relation to its alignment on the imaging modality, an indication of its effects in terms of observed magnitude and direction.

In the case of 3 -Dimensional image generation by imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI), the raw data generated during the image acquisition contains a volume of data containing attenuation values in spatially defined positions relative to orthogonal axes in three imaging reference planes x, y and z in the case of computed tomography (CT), and signal emanation and registration by the imaging modality of a proton undergoing a nuclear and / or an electronic shell relaxation process that emits radio- frequency waves as a consequence, and by which collectively a volume of data may be generated containing these relaxation events and spatially defining them within the volume to give an indication of concentration, distribution and spatial definition relative to three orthogonal reference planes x, y and z, in the case of magnetic resonance imaging (MRI).

The images may be evaluated in their 2-Dimensional form for elongation and distortion effects, but because of the "volumetric" method of acquisition, the data can be loaded into a 3- Dimesional viewing platform such as multi-planar reconstructions (MPR' s), maximum intensity projections (MIP's) and curved reconstruction to produce an image of the structure within a surrounding volume and which may be freely orientated in space to obtain a preferred image projection for measuring using the installed image measuring tools supplied with that imaging modality.

The universal imaging phantom images may be used to determine the measurement accuracy of software measuring tools installed on diagnostic, clinical review, internet browser and teleradiology workstations, such that images that have been transferred across networks may be evaluated for changes due to conversion, transfer and reconstruction effects. The universal imaging phantom provides a set of modality specific radiological phantoms which may be used to generate an image, series of images, screen capture or volume of image data, with each modality specific radiological phantom introducing known values or reference values of diameter, area, volume and length into the image, so that when viewed and measured using the modality measurement tools, a comparison of measurement accuracy may be obtained by the user as to the accuracy of measurement relative to the method of viewing, the effects on measurement accuracy of orientation, and the range of variations that may occur in measured values as against the reference values of the particular modality specific radiological phantom. Additional information may be obtained regarding the measurement accuracy of a given imaging modality as compared to other dissimilar imaging modalities as in the case of digital subtraction ^* angiography (DSA) against computed tomography (CT) against magnetic resonance imaging (MRI), and further measurement accuracy comparisons between imaging machines of a given modality as in comparing a range of different types of computed tomography (CT) imaging machines, and further comparisons between similar types of imaging machines of a given imaging modality as in the case of testing similarity of the same computed tomography (CT) scanner on different sites.

It can therefore be appreciated that there arises a need for a quality assurance radiological phantom to assess the measurement accuracy of images produced by various imaging modalities and used in the diagnosis and treatment of illnesses in patients, and where images may be transferred to remote viewing, evaluation and reporting stations, such that and variations in the content and presentation of the image may not be readily appreciated by the user but may result in an unknown level of variation and interpretation of the image(s) and the measured values of diameter, area, volume and length as perceived by the reporter. There is a continued requirement therefore for a specialised and innovative quality assurance phantom that addresses these needs for calibration and performance testing of a variety of medical diagnostic and treatment imaging modalities used in the treatment of patients, and the universal imaging phantom provides the range of modality specific radiological phantoms required to fulfil this role.

SUMMARY OF THE INVENTION

The range of radio-diagnostic imaging modalities now made available to clinicians in healthcare has enabled them to manage their workload and increase their efficiency. With regard to the stated disadvantages of certain types of medical diagnostic and treatment devices in their accepted forms and configurations and detailed in the prior art, the universal imaging phantom provides a comprehensive phantom system that incorporates aspects of the advantages of other phantoms defined in the prior art, but none of the disadvantages or their limitations. It introduces a new aspect of evaluation concerned with the accuracy of out-of-plane non-linear measurement in 3-Dimensional image display environments and the capacity of new software based measurement tools to produce accurate and closely matched measurements of images of the universal imaging phantom with its known reference value(s) of diameter, area, volume and length of its modality specific radiological phantoms. This invention relates to a quality assurance phantom system called in this patenting application a "universal imaging phantom", and its range of fixedly / releasably mounted "modality specific radiological phantoms" and their methods of use for the systematic testing of radio-diagnostic imaging modalities including digital subtraction angiography (DSA), computed tomography (CT), magnetic resonance imaging (MRI), radio-fluoroscopy (RF), nuclear (isotope) imaging (NI) scanners and computed radiography (CR) machines, and picture archive and communications systems which include diagnostic, clinical review, and internet browser workstations which query / retrieve medical image(s) and other image related information from a central image archive for displaying, manipulation and evaluation of images. The images of the modality specific radiological phantom for computed radiography (CR) can also be used to test and evaluate image(s) transferred by teleradiological or satellite technology to remote viewing and diagnostic imaging facilities.

The universal imaging phantom and its related modality specific radiological phantoms is used for evaluating the measurement accuracy of an imaging modality in terms of the hardware which images the phantom, the conferred image characteristics due to the method(s) of imaging or any advantages / disadvantages incumbent in the design and construction of the imaging machine. On reconstruction of the image(s) or series of images, the inherent information contained within the image(s) relating to markers) internal or external of the said modality specific radiological phantom(s) may be measured using the imaging modality measurement tools and the derived value(s) may be compared for measurement accuracy purposes against the reference value(s) of diameter, area, volume and length of the said modality specific radiological phantom.

The term "universal imaging phantom" is used to describe this radiological quality assurance phantom since the base frame and phantom support columns provide attachment for a wide range of modality specific accessory phantoms. The universal imaging phantom provides a wide range of testing across different imaging modalities and machines of each particular modality thus allowing their measurement accuracies to be compared. It its most basic form and ascending in complexity, it comprises of a base frame 1 and a single phantom support column 6 (Figure 1), a base frame I and two phantom support columns 6 (Figure 2), or a base frame 1, one or two phantom support column(s) 6 and an accessory phantom base plate 47 (Figure 3). An additional accessory phantom supporting block 51 may be engaged into the locator groove 49 of the accessory phantom base plate 47 for supporting other phantoms like the modality specific side mounted accessory phantom for nuclear (isotope) imaging 69. In the way of example only, the ) addition of a modality specific accessory phantom for computed tomography (CT) 54 may be slotted into the locator groove 49 of the accessory phantom base plate 47 in addition to the two phantom support columns 6 (Figure 4) where in addition x, y and z-axis measurement tubes may be releasably / fixedly attached to the phantom support column(s) as required such that the universal imaging phantom is ready to be imaged.

The test frame comprises of two longitudinal members 2 and two lateral members 3 which are joined at their ends by a fastener to form a square, rectangular or otherwise preferred shaped base frame upon which a phantom support column 6 is releasably or fixedly secured by securing into hole(s) 4 on the inner faces of the longitudinal members. There are plurality 5 of holes in which the locking extension 7 of the phantom support column 6 is engaged with the hole(s) 5 of the longitudinal member 2 of the base frame 2. The phantom support column(s) 6 is a square, oblong or otherwise preferred shaped section of thinner cross-section, containing a plurality of octagonal sockets 8 which are arranged in a linear and staggered manner on the widest faces of the fixing column. The octagonal sockets 8 function to releasably or fixedly mount a singularity or plurality of z-axis measurement tubes 12 which are one of the modality specific radiological phantoms of the universal imaging phantom. The z-axis measurement tube(s) 12 consists pre-formed tube(s) composed of a strong thermoplastic or polymer and transparent that is moulded into a section with a head, body and base, and by which location of the head and body of the measurement tube into the octagonal socket(s) 8 of the fixing column allows them to be located, positioned and releasably / fixedly retained. The pre-formed tubes varying in diameter and length, and the sections are blocked and sealed at both ends of the tubular structure, the nearest end forming an octagonal shaped socket and plug that may be used to mount, secure and orientate the said z-axis measurement tube 12 inside the octagonal socket 8 of the phantom support column 6, while the furthest forms an end plug to the said z-axis measurement tube, and whose internal diameter multiplied by its length forms an "imaging volume". The pre-formed tube(s) are made into a variety of shapes designed to pass through at least two of the three orthogonal imaging planes and maximally through three. The transitions between each orthogonal plane of reference forms a further plane of reference termed as oblique plane. The cross-section of each measurement tube divides the wall of the measurement tube 14 into four quadrants 15 along the length of the internal chamber and between the said plug ends. Passing at its geometrical centre along the length of the internal chamber is a central wire 16 typically made of copper which has a series of graduated notches which denote a preferred scale of measurement. The interior chamber of the measurement tube is filled with oil, diluted radio-opaque contrast media, gadolinium based magnetic resonance imaging contrast media, combination of said fluids, or other suitable material. The x-axis measurement tubes 12 will vary in shape between linear and curved, and curved measurement tubes will have a singularity or plurality of lesser or greater curvatures or ranges of tortuosity (Figures 18-28).

The phantom support column 6 has graduations of metric, Imperial or other unitary scale of measurement on the edges of the column 13 and two sets of clip extensions 9 on each of its two widest faces for retention of up to two smaller linear measurement tubes called the x-axis linear measurement tube 10 and the y-axis linear measurement tube 11 mounted on its surfaces. This is to allow for easier setting up of the test tool in the imaging area of the scanner for iso-centric measurements in line with the centring lasers of the scanner, and also to ensure that a linear scale is included across the x and y axes of the scanners) at their isocentre. The configuration of the universal imaging tool is based according to the imaging modality or the purpose of the image(s). Testing of measurement accuracy may be carried out using the x-axis 10 and y-axis 11 linear measurement tubes and the z-axis modality specific accessory phantom for computed tomography (CT) 54, which is one of the array of CT evaluation tools that when imaged produces an image of parallel lines composed of regularly spaced dots, each of which corresponds to 5 millimetre markers arranged on a rod (measurement rod) and inserted into the hollow tunnel which traverses from one end of the limb of the CT accessory phantom to the other end. There are five of these measurement rods inserted into the phantom, one in each of the opposing four limbs, of which there are two sets of asymmetric limbs, one being twice the width of the other on the opposite side, and similarly below the arrangement is repeated but in an opposite fashion, such that the smaller or larger limb is always in a close but opposite position relative to the body of the computed tomography (CT) accessory phantom 54, and where the final rod is placed into the body of the phantom at its mid-point. The configuration of the opposing limbs and relativity to the body allow images to be generated which when viewed in the three orthogonal planes produce five lines of regularly spaced high attenuation dots which correspond to the radio-opaque markers of the measurement rod(s). These dots have a spatial relationship to each other and each line has a known distance of separation to each other for every orthogonal plane. The separation of the dots in any plane of view should be typically 5 millimetres between the centres of each consecutive dot and the separation of the lines should be in accordance with the typical values stated in each of the respective views by way of example only. The lines should be parallel to each other throughout the length of the measurement rod(s) and this reflects the capability of the scanner to image the phantom and produce spatially accurate images for each individual image section or volume. The ability to do this may be termed as "transcriptional linearity" for evaluating its ability to create straight lines, and "parallelism" for evaluating its ability to produce lines that are parallel to each other. The image(s) may be viewed using 2-Dimensional and 3-Dimensional displays and measurements) may be performed using conventional "point-to-point" techniques, or they may be loaded into volumetric viewing platforms which include multi-planar reconstructions (MPR' s), maximum intensity projections (MIP 's) and curved reconstruction and the measured value(s) of diameter, area, volume and length may be compared to the known reference value(s) contained internally and externally on the phantom.

The universal imaging phantom is designed to be set into a particular configuration and then to be imaged on multiple imaging modalities. The use a base frame 1, phantom support column 6 and a selection of z-axis measurement z-axis measurement tube(s) enables evaluation of a magnetic resonance imaging (MRI) scanner. The imaging of the said phantom configuration can be achieved in air, but better images may be obtained by encapsulating the phantom inside a fluid filled enclosure called the magnetic resonance imaging tank enclosure 30.

In the case of MRI measurements), the assembled said base frame 1, phantom support column(s) 6 and measurement tubes (reference and measurement) 10,11,12 are receivable in an external tool holder for final assembly prior to testing. Said external tool holder construction consists of perspex, acrylic or other transparent, strong, durable and non-magnetic material that functions as an enclosure for the said modality specific accessory phantom(s). The advantages of mounting the base frame and measurement tube(s) within a water bath and imaging using magnetic resonance are that it results in better quality images and the oil markers are more easily visualised. A further benefit of testing in water is that it is far easier to visualise the walls of the measurement tube since they appear as low signal (dark) areas or rings surrounded by brighter fluid on the outside and brighter fluid with the walls of the measurement tubing. The magnetic resonance imaging tank enclosure functions to support the universal imaging phantom within the volume of fluid inside the tank enclosure. It is placed into the imaging area of the scanner and levelled using a combination of the positioning laser lights on the scanner, the spirit levels on the tank enclosure, and levelling with the adjuster feet of the tank enclosure. The phantom is now ready to be imaged with a suitable pulse sequence. The images obtained may be viewed and measured using 2-Dimensional and 3-Dimensional displays similar to computed tomography (CT) and the images of the phantom may be measured value(s) of diameter, area, volume and length may be compared to the known reference value(s) contained internally and externally on the phantom.

Other modality specific accessory tools may be used with the base frame and phantom support column(s) and this may be facilitated by use of the accessory phantom base plate 47 which is inserted into the base frame 1 and locked into position releasably / fixedly with a fastener. The said base plate has a locator groove 49 to allow other modality specific accessory phantoms to be mounted, as well as another component called the accessory phantom supporting block 51 which will facilitate the mounting of other modality specific accessory phantoms in a number of other orientations.

In addition the modality specific accessory phantom for nuclear (isotope) imaging 60 enables the z-axis testing of length and linearity to be evaluated on isotope imaging (gamma) cameras. The said phantom is similar to the accessory phantom supporting block 51 with the exception that at each top and bottom part of the phantom body is a symmetrically drilled tunnel which runs along the length of the phantom body (Figure 37). A lead insert is placed into the full length of the tunnel 61, which also carries a steel tube with accurately placed and spaced pin-hole apertures 63 that pas through both the lead and steel. Placed into this cylinder and sealed in with a screw cap 66 at the one end is a plastic tube 67 that carries the isotope as a sealed radio-active source. The phantom may use one or two lines arrays of the radiation emitting tubes, but utilisation of the modality specific side mounted accessory phantom for nuclear (isotope) imaging 60 which may be slotted into the locator grooves 53 on each side of the said phantom enables a further two radiation sources to be used if preferred to create a 3 lined array (Figure 41) or a 4 lined array to be used (Figure 42). The construction may be imaged in close proximity with the scintillation crystal of the gamma camera or positron emission tomography scanner and the acquired images may be evaluated for position, diameter and spacing of "hot-spots" which are areas on the display of the imaging apparatus that provide an assessment of x, y and z-axis geometry in an image and distance measurement between the centres of these "hot-spots" (Figure 43).

The modality specific accessory phantom for computed radiography (CR) 71 fits and is fastened into the base frame 1 in a similar fashion to the accessory phantom base plate 47. The said phantom may be used with up to two phantom support columns 6 and preferred z-axis measurement tube(s) such that an image may be taken on a computed radiography imaging plate to produce an image which has the pattern of the specific modality accessory phantom for computed radiography (CR) in the centre, and additionally images of the z-axis measurement tube(s). Evaluation of the images will demonstrate any geometrical distortion in the image(s), levels of magnification which can be corrected by reference to the said phantom reference value(s), image contrast indices, sensitometric information, information on resolution of the imaging system, off-centre elongation and magnification effects, and peripheral image measurement accuracy as evaluated by the z-axis measurement tube(s) with their internal graduated marker scale on the central wire 16.

The image(s) of the modality specific accessory phantom for computed radiography 71 may be used as a reference image with standardised values of length between radio-opaque edge markers 73 longitudinally and laterally, length of diagonal marker lines and intervals 74, diameter of circle in the centre of the test image 75, assessment of imaging field or display geometry with reference to the geometrical shape module 76, assessment of resolution and modulation transfer function with the incorporated resolution module and the assessment of sensitometric information by reference to the wedge filter sensitometric module.

The image(s) may be used to evaluate changes in any part of the imaging chain or as a consequence of image transmission and reconstruction. The image(s) may be evaluated and compared against the reference values following image reading and construction, after it has been transferred across local area networks to other image diagnostic, clinical review or internet browser facilities, and following transmission to wide area networks and satellite transmission to remote viewing and reporting facilities.

The modality specific accessory phantom (tubular) for computed radiography (CR) is an additional means of assessment for the planar image of computed radiography and allows evaluation of the generated image to be compared against a range of measurement tubes of known diameter and length in a longitudinal, transverse and oblique orientation across the imaging field so that field geometry, magnification of an image and distortion effects can be estimated.

Another modality specific phantom of the universal imaging phantom is the configuration using the modality specific phantoms for computed tomography 54 and nuclear (isotope) imaging 60,69 in combinations so that computed tomography (CT) / positron emission tomography combination scanners may be evaluated in much the same way as detailed previously for both imaging modalities.

Another phantom that is part of the array of phantoms constituting the universal imaging phantom is designed to indicate on the image whether there are any planar measurement inaccuracies between two measured points of an object that might not be readily appreciated when viewing in 2-Dimensional and 3-Dimensional image displays and using the software measurement tools that are installed by manufacturers of imaging modalities. The modality specific measurement correction phantom for computed tomography (CT) 91 is essentially a construction containing parallel lines of typically low radio-opacity spheres that are arranged in columns and rows and in line such that they form typically a 1 centimetre matrix in all directions. The construction is mounted below the subject to be imaged and preferably in the table of the scanner. The image(s) or volume generated include below the subject image(s) of the 1 centimetre matrix which can be used to indicate to the user variances in longitudinal, oblique and transverse linear measurement from what is measured by the measuring tool(s) of the imaging modality as against the dimensions of the 1 centimetre matrix. There is also a reference section containing disks of known diameter which is included in the matrix image and by which the diameter of the disk can be measured and compared against the reference value(s) thus indicating reconstruction anomalies such as distortion, magnification or minification and where lines may be drawn from point to point of the matrix to enable accurate and referenced measurement (Figures 52-58).

The modality specific measurement correction phantom for magnetic resonance imaging (MRI) 119 is similar in design and construction as the previoμsly described computed tomography (CT) counterpart, except that instead of using spheres of low radio-opacity it uses oil based or magnetic resonance signal producing fluid in capsules which when imaged are able to generate a similar and typical 1 centimetre matrix which can be used to provide a reference against measurement of image(s) performed using the image measurement tools of the scanner (Figure 61).

BRIEF DESCRIPTION OF THE DRAWINGS

FIGURE 1 illustrates in a 3-Dimensional drawing of the two longitudinal and transverse members of said base frame, holes for location of releasable / fixed fasteners for securing the phantom support column(s), with one phantom support column in place.

FIGURE 2 illustrates in a 3-Dimensional drawing of the two longitudinal and transverse members of said base frame, holes for location of releasable / fixed fasteners for securing the phantom support column(s), with two phantom support columns in place.

FIGURE 3 illustrates in a 3-Dimensional drawing of the two longitudinal and transverse members of said base frame, holes for location of releasable / fixed fasteners for securing the phantom support column(s), with two phantom supports in place and accessory phantom base plate.

FIGURE 4 illustrates in a 3-Dimensional drawing of the two longitudinal and transverse members of said base frame, holes for location of releasable / fixed fasteners for securing the phantom support column(s), with two phantom supports in place, accessory phantom base plate and accessory phantom for computed tomography (CT). FIGURE 5 illustrates in a 3-Dimensional drawing of the two longitudinal and transverse members of said base frame, holes for location of releasable / fixed fasteners for securing the phantom support column(s), with two phantom supports in place and accessory phantom base plate, and accessory phantom supporting block.

FIGURE 6 illustrates in a 3-Dimensional drawing of the two longitudinal and transverse members of said base frame, holes for location of releasable / fixed fasteners for securing the phantom support column(s), with two phantom supports in place and accessory phantom base plate, and accessory phantom for nuclear (isotope) imaging (3 line ported array).

FIGURE 7 illustrates in a 3-Dimensional drawing of the two longitudinal and transverse members of said base frame, holes for location of releasable / fixed fasteners for securing the phantom support column(s), with two phantom supports in place and accessory phantom base plate, and accessory phantom for nuclear (isotope) imaging (4 line ported array).

FIGURE 8 illustrates a perspective view of a phantom support column with X-axis measurement tool, locking extensions of phantom support column, retaining clips and octagonal sockets.

FIGURE 9 illustrates a side elevational view of the phantom support column with its graduation markings and opposite faced central axis x and y linear measurement phantoms.

FIGURE 10 illustrates a plan view of the phantom support column with its graduation markings and opposite faced central axis x and y linear measurement phantoms.

FIGURE 11 illustrates a perspective view of the phantom support column with x and y axis graduated scales and octagonal sockets.

FIGURE 12 illustrates a perspective view of the measurement tube design.

FIGURE 13 illustrates a plan view of the measurement tube design.

FIGURE 14 illustrates a short linear measurement tube.

FIGURE 15 illustrates a long linear measurement tube (over 20 centimetres in length).

FIGURE 16 illustrates a single arched or angular measurement tube.

FIGURE 17 illustrates a double loop measurement tube.

FIGURE 18 illustrates a truncated or spiral measurement tube.

FIGURE 19 illustrates a sinusoidal wave shaped measurement tube.

FIGURE 20 illustrates a circular shaped measurement tube.

FIGURE 21 illustrates an oval or ovoid shaped measurement tube.

FIGURE 22 illustrates a high amplitude sinusoidal wave shaped measurement tube.

FIGURE 23 illustrates a triangular measurement tube.

FIGURE 24 illustrates a four section angulated measurement tube.

FIGURE 25 illustrates a phantom support column and measurement tube attachment.

FIGURE 26 illustrates a magnetic resonance imaging (MRI) tank enclosure and adjuster feet.

FIGURE 27 illustrates a perspective view of the construction of the magnetic resonance imaging

(MRI) tank enclosure.

FIGURE 28 illustrates a perspective view of the cover plate of the magnetic resonance imaging

(MRI) tank enclosure.

FIGURE 29 illustrates a side elevational view of the cover plate of the magnetic resonance imaging (MRI) tank enclosure.

FIGURE 30 illustrates a 3-Dimensional view of the tank enclosure adjuster feet.

FIGURE 31 illustrates a 3-Dimensional view of the accessory phantom base plate.

FIGURE 32 illustrates a 3-Dimensional view of the accessory phantom support block.

FIGURE 33 illustrates a modality specific accessory phantom for computed tomography (CT).

FIGURE 34 illustrates the geometrical aspects of the modality specific accessory phantom for computed tomography (CT) and the appearances of the cylindrical measuring rods on computed tomography images in the axial plane.

FIGURE 35 illustrates the geometrical aspects of the modality specific accessory phantom for computed tomography (CT) and the appearances of the cylindrical measuring rods on computed tomography images in the sagittal plane. FIGURE 36 illustrates the geometrical aspects of the modality specific accessory phantom for computed tomography (CT) and the appearances of the cylindrical measuring rods on computed tomography images in the coronal plane.

FIGURE 37 illustrates a side elevational view of a modality specific accessory phantom for nuclear (isotope) imaging.

FIGURE 38 illustrates a perspective view of the pin-hole apertures of outer steel cylinder.

FIGURE 39 illustrates a perspective view of the inner plastic isotope holding tube.

FIGURE 40 illustrates a 3-Dimensional view of the modality specific accessory phantom for nuclear (isotope) imaging.

FIGURE 41 illustrates a 3-Dimensional view of the modality specific accessory phantom for nuclear (isotope) imaging, with a two or three lined array.

FIGURE 42 illustrates a 3-Dimensional view of the modality specific accessory phantom for nuclear (isotope) imaging, with a four lined array.

FIGURE 43 illustrates the spatial relationships of the assembled four sectioned nuclear (isotope) imaging (NI) modality specific accessory phantom as seen on the modality display in sagittal or coronal orientation and using a 3 or 4 lined array.

FIGURE 44 illustrates a plan view of the modality specific accessory phantom for computed radiography (CR).

FIGURE 45 illustrates a plan view of the modality specific accessory phantom (tubular) for computed radiography (CR).

FIGURE 46 illustrates a perspective view of the measurement tube retaining clips.

FIGURE 47 illustrates a plan view of the measurement tube retaining clips.

FIGURE 48 illustrates a plan view of the modality specific accessory phantom (tubular) for computed radiography.

FIGURE 49 illustrates a side elevational view of the modality specific accessory phantom for computed tomography (CT).

FIGURE 50 illustrates a side elevation view of the modality specific accessory phantom for computed tomography (CT) in combination with the modality specific accessory phantom for nuclear (isotope) imaging for testing a computerised tomography (CT) and positron emission tomography (PET) combination scanner.

FIGURE 51 illustrates a plan view of the modality specific accessory phantom for computed tomography (CT) in combination with the modality specific accessory phantom for nuclear

(isotope) imaging for testing a computerised tomography (CT) and positron emission tomography (PET) combination scanner.

FIGURE 52 illustrates a patient in a computed tomography (CT) scanner.

FIGURE 53 illustrates the distance relationships between measurements) of patient anatomical parts in different planes of viewing.

FIGURE 54 illustrates a coronal view of the modality specific measurement accuracy correction phantom for computed tomography (CT) correction matrix.

FIGURE 55 illustrates a sagittal view of the modality specific measurement accuracy correction phantom for computed tomography (CT) correction matrix.

FIGURE 56 illustrates an axial view of the modality specific measurement accuracy correction phantom for computed tomography (CT) correction matrix.

FIGURE 57 illustrates the reference disks and lines of the measurement correction accessory phantom for computed tomography (CT).

FIGURE 58 illustrates a coronal view of the typical positioning of linear and triangular reference points for referencing and calculating linear distance(s).

FIGURE 59 illustrates the modality specific measurement accuracy correction phantom for magnetic resonance imaging (MRI) with a sagittal view of the correction tool matrix and linear and triangular reference points. FIGURE 60 illustrates the modality specific measurement accuracy correction phantom for magnetic resonance imaging (MRI) with a coronal view of the correction tool matrix and linear and triangular reference points.

FIGURE 61 illustrates the modality specific measurement accuracy correction phantom for magnetic resonance imaging (MRI) with an X2 magnified axial transverse view of the measurement correction matrix with linear and triangular reference points.

DETAILED DESCRIPTION OF THE INVENTION

A complex radiological phantom for use with (a) computed tomography (CT), which is defined as a method of producing images of body organs by scanning them with X-rays and using a computer to construct a series of cross-sectional scan images along a single axis, (b) magnetic resonance imaging (MRI), which is defined as a specialised imaging technique to create medical images of internal structures of the body, particularly the soft tissues by using the influence of a large intensive magnet to polarise hydrogen atoms in the tissues and then which measures the summation of the spinning energies within the cells, (c) digital subtraction angiography (DSA), which is defined as the procedure for visualising blood vessels with contrast medium in a bony environment by subtracting the pre-contrast image (the mask) from the image(s) with the contrast medium, (d) radio-fluoroscopy (RF), which is defined as an imaging method commonly utilised by physicians to obtain real-time images of internal structures of the body through the use of a fluoroscope, which consists of an X-ray source and fluoroscopic imaging device between which a patient is placed and the radiological image(s) viewed, (e) isotope (nuclear) imaging (NI) which is defined as an imaging technique using short lived radio-active compounds that may be injected into the body, and by using the resultant emission of gamma rays, which may be detected by a sensitive imaging head of a gamma camera placed above or below the patient, such that the crystals contained in the imaging head is able to register scintillations when hit by gamma photons emitted from within the patient, and which ultimately when collected over time or the number of counts, is able to produce an image that shows the distribution of the radio-isotope within the body, (f) computed radiography (CR) which is defined as a solid state imaging device, such as a photo-stimulable phosphor, that may be used to record the image(s) of a patient part that had been prior irradiated by X-rays, and where the phosphor plate is recovered, enhanced and displayed as a medical image using a digital computer, and (g) tele-radiographic and networked radiological images which are defined as medical image(s) that are transferred over digital or other networks using a standardised transmission protocol, for example Digital Imaging and Communications in Medicine (DICOM) which is a comprehensive set of standards for handling, storing, printing, and transmitting information in medical imaging, whereby image(s) of the universal imaging phantom are used to indicate errors of measurement accuracy by providing image(s) of the said phantom by the respective imaging method(s), and using the reference(s) of diameter and length contained in and on the phantom, and to evaluate the capacity of a given imaging machine to reproduce measurement value(s) identical or of the closest identical match to the reference value(s) of the phantom or its specialised tool modality specific accessory phantom(s), and where said universal imaging phantom consists of a base frame 1 and phantom support column(s) 6 for the mounting of a range of modality specific accessory phantom(s) which when selectively and independently configured and imaged will generate 2-Dimensional image(s) and 3-dimensional image data sets (volume acquisition), 2-Dimensional radiological planar images, screen capture images, images of other pictorial or graphical format(s), or combinations of said image(s) types of the universal imaging phantom in a required position in / on the selected or preferred imaging apparatus, and where the volume image data set, image(s), series of images or screen captures of the radiological phantom functions as an omni-directional. non-planar linear, planar linear distance, cross-sectional area and volume reference tool, and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, enables the phantom tool(s) to function primarily to evaluate the response of the scanner 3-Dimensional image registration software (volumetric), or other image display and measurement evaluation system(s), to process and generate from the raw data produced during the image acquisition stage of scanning, image(s) or series of images of the universal imaging phantom, which ideally should be accurately represented in terms of both its 3-Dimensional spatial co-ordinates and planar variations) during the static, incremental or translational (dynamic) imaging processes of the respective imaging modality chosen, as for example in the case of computed tomography (CT) or magnetic resonance imaging (MRI), or during static imaging processes as in digital subtraction angiography (DSA), radio-fluoroscopy (RF), nuclear (isotope) imaging (NI), computed radiography (CR), or in combinations of said imaging modalities and other specialised imaging modalities, to further validate their recognised capabilities of accurately measuring parametric value(s) of cross-sectional diameter(s), area(s), non-linear and linear length(s), and volume, as compared against the known and stated reference value(s) for the particular universal imaging phantom configuration or modality specific accessory phantom(s), and to selectively apply this phantom in measurement situations where the subjects) being imaged or the area(s) of interest are predominantly of a non-linear shape or configuration, and where the imaged structure(s) or subject(s) describe or exhibit a continuous, intermittent or combined non-linear 3-Dimensional variations) in its spatial and vector coordinates (along x, y, z and oblique axes) along all or any part of its structure(s), and where the established methods of linear measurements) when applied to 2-Dimensional planar measurements), or 3-Dimensional measurements) only involve any combination(s) of only two out of the three axis (x, y and z) components) of the imaged and measured structure(s), and is seen to produce both erroneous and unpredictable measurement value(s), and also found in circumstances where measurements) of existing designs of other commercially available 3-Dimensional linear reading quality assurance phantom(s) with their own system of integrated measurement reference(s) are found to be limited in their range of application to predominantly linear or oblique measurements) in a restricted range of orientations, but where it is entirely unsuited to measuring objects which are out of a particular measurement plane, and where the image(s) has recorded a structure which is non-linear, convoluted, curvate, concentric, eccentric, curvilinear, circular, spherical, truncated or spiral in its shape, and to which the aforementioned universal imaging phantom may be used to evaluate the capabilities of different imaging modalities and imaging machine(s) to accurately image, display and measure out-of-plane reference image(s) containing linear and non-linear structures and the references of measurement contained therein, such that the process may be regarded as a primary tool function, and by way of its design provides an array of modality specific accessory phantoms, along with each respective image modality principle(s) of operation, method(s) of use, and universal imaging phantom function(s) that may be employed in linear measurement accuracy verifications) for each of the imaging modalities and imaging apparatus that is to be tested, and which may regarded as a secondary tool function.

The universal imaging phantom has been constructed to provide highly accurate, reproducible, and reliable measurement(s) of any marked, delineated or otherwise indicated linear, curvate, concentric, eccentric or curvilinear line(s), plane(s) of interest, area(s) or volumφ) contained in the respective imaged modality specific accessory phantom in any singularity, multiplicity or combination(s) of the aforementioned value(s), functions) or properties of the particular accessory phantom or combination to the nearest millimetre (metric), sub-division of inch (Imperial) or other approved designation of interval, distance, area or volume. Referring now to figure 1, there is shown a universal imaging phantom comprising a base frame 1 (Figure 1) onto which a variable number of modality specific accessory phantom(s) are connectable, and in which the base frame 1 is substantially rectangular and comprising; two longitudinal members 2 and which are connected to each other at their ends by two lateral members 3 with the two longitudinal members 2 being placed in parallel and in line with each other, and spaced at their extremes, positioned squarely and secured releasably / fixedly by a non-magnetic screw, clip or other fastener to the lateral members 3 which are placed in-between and at the ends of the two longitudinal members 2. The longitudinal members 2 and lateral members 3 may typically be constructed from wood, perspex (RTM), acrylic or other suitably non-magnetic material or combination of materials, with each of the lateral members 3 comprising at least one drilled locating hole 4, being shown in the present example, and each of the longitudinal members 2 comprising a plurality of locating holes 5 spaced at regular intervals along its internal face, and by way of example only, the locating holes 5 are spaced at 40 millimetre intervals, along the internal face, with each locating hole 4 typically 5 millimetres in diameter and extending through the longitudinal member 2 with allowance for the spacing of these holes and their diameter(s) may be modified according to the overall dimensions of the universal imaging phantom, and with the dimensions of the two longitudinal members 2 typically 450 millimetres length by 20 millimetres by 20 millimetres square and uniform along their lengths, the said sections forming by way of example only, an oblong base frame of 450 millimetres by 240 millimetres, but it should be appreciated that the base frame 1 can be of any shape and its dimensions can be selected as required, and additionally and typically held in position with fixing devices such as brass screws or suitable screw equivalents composed of other non-magnetic materials or alloys that may be used to connect the said components of the base frame 1 together, and where in the case of wooded base frame constructions, where the universal imaging phantom is required to be imaged whilst immersed in a water filled container, as in the case of measurements using magnetic resonance imaging machines, where the frame is intended to be totally enveloped in water of another fluid, the fixings may comprise nylon, aluminium alloy or other suitable non-magnetiseable material equivalents for the fixing of the perspex (RTM), acrylic, or other equivalent non-magnetic material base frame that may be likely to be used, not withstanding other variants or combinations of materials that may be used and for practicality reasons or advances in materials technology where new materials may provide enhanced performance, increased durability or greater mechanical stability. The universal imaging phantom consists of a base frame 1 and phantom support column(s) 6 for the mounting of a wide range of modality specific accessory phantom(s) which may be releasably or fixedly to the phantom support column 6, which may be mounted perpendicularly to the said base frame 1, and across the width of the base frame, the vertical column 6 being a section of typical dimensions of 240 millimetres width, 150 millimetres height and 20 millimetres thickness, and with two extensions 7 attached and continuous with its lowermost and lateral aspects of the section, serving to interface with the innermost and longest facet of the longitudinal meiriber(s) 2 of the base frame 1, having typical dimensions of each of the said extensions of 15 millimetres length, by 10 millimetres width, and 20 millimetres height, and on the innermost or medial faces of these sections, and in the geometrical centre, is a 5 millimetre drilled hole that may be lined up with a preferred hole 4 on the innermost aspect of the longitudinal member(s) 2 of the said base frame 1 where an unthreaded nylon or other suitable non-magnetic material headed locking pin may then be placed into each of the two holes to allow the sections to be fixedly or releasably and / or variably secured together into the base frame 1, and where the diameter of the pin(s) would typically be fractionally below 5 millimetres, its length 30 millimetres, whilst its head diameter 15 millimetres and shoulder thickness of 5 millimetres, and where for illustration purposes only, a typical setup of said base frame 1 and said phantom support column 6 is shown (Figure 1). The said phantom support column 6 is held in position by a square or oblong or other suitably shaped locking extension 7 of the lowermost and lateral aspect of the phantom support section 6 which has a drilled hole in its structure so that it may be lined up with a corresponding hole(s) of the longitudinal members 2 of the base frame 1, and is held in place by engagement of both lateral faces of the locking extensions 7 of the phantom support column 6 with the medial or innermost faces of the longitudinal members 2 and the insertion of a locking pin or other suitable fastener into the lined-up holes of both said components. The said base frame 1 may be configured to hold more than one phantom support column 6 (Figure 2) and may be modified to include other modality specific accessory phantoms by insertion of an accessory phantom base plate 47 (Figure 3) to further include by way of example only, a modality specific accessory phantom for computed tomography (CT) that is slotted into the locator groove 49 of the accessory phantom base plate 47 (Figure 4), or an accessory phantom supporting block 51 (Figure 5), or modality specific accessory phantom for nuclear (isotope) imaging 60 with a 2 lined array, or with a single attached modality specific side mounted accessory phantom for nuclear (isotope) imaging 69 (Figure 6) with a 3 lined array, or with a further additional specific modality side mounted accessory phantom for nuclear (isotope) imaging 69 (Figure 7) with a 4 lined array.

The said phantom support column 6 comprises at least one octagonal or otherwise shaped socket 8, (Figure 8) with the / or each socket typically comprising an octagonal hole which extends substantially horizontally through the phantom support column 6, and having a flat-face to opposite flat-face distance typically of 10.5 millimetres and where the phantom support column 6 comprises a plurality of octagonal or otherwise shaped sockets 8, the sockets being arranged in vertical and horizontal rows (Figure 8), with each alternate row typically off-set from the one above and below typically by a factor of 50% of the distance between the centre of one socket to that of another either horizontally or vertically, and where the choice of staggered rows is designed to increase the peripheral or outer measurement capabilities of the tool, while a more in-line configuration may be used to facilitate more centralised and central axis / iso-centric based testing methods.

The phantom support columns 6 have attached to each square or oblong face and at mid-point at each of the points corresponding to 0 degrees, 90 degrees, 180 degrees and 270 degrees, a singularity or plurality of clip extensions) 9 or interfacing sockets for receiving a specified diameter tubular measurement reference tool(s) 10, 11 integrally incorporated into each phantom support column(s) 6. The clip extensions) 9 is / are incorporated at the middle point and at the extremes of the geometrical x and y axes of each face of each phantom support column(s) (Figure 8), and where at all four edges of the said support column 6 there will be scalar markings, by way of example only, of metric graduations 13 along all of the edges (Figures 9, 10) allowing the tester to view the metric graduations 13 from both sided of the phantom support column(s) by using a colour of permanent and water resistant paint or polymer chosen for the phantom support column 6 that will contrast with the graduations on the scales 13 so as to maximise reading accuracy.

A linear measurement tool may be incorporated into clip extensions 9 of the phantom support column(s) 6 in the form of an x-axis 10 or y-axis 11 linear reference measurement tube(s) which is receivable into the / each corresponding axis clip extensions) 9, or / in combination with a singularity or plurality of non-linear z-axis tube(s) 12 in the / or each octagonal socket 8, typically with the / or each measuring tube(s) comprised of formed thermoplastic, polymeric compound, silicon rubber derivative or other suitable transparent, non-magnetic, radiolucent and durable material, each said measuring tube(s) designed and constructed to provide a range of z- axis tubes having a range of variable length, cross-sectional diameter and single or repeated sections of variable curvature or tortuosity, and where the x-axis 10 and y-axis 11 linear measurement tubes typically having an external diameter of 10 millimetres, an internal diameter of 8 millimetres and which are straight or rectilinear throughout their complete length, and whose is to serve as subsidiary tools for linear reference diameter(s), and length. Each linear and non-linear measurement tube 10, 11, 12 has its walls divided into sections 15 to create hollow quadrants 15, each having its cross-section divided into four, by way of example only, and where each said quadrant(s) 15 extends along the length of the measurement tube, and having typically a wall thickness of 0.5 to 3.0 millimetres thick, and typically extending from the point where it meets the circumference of the internal diameter of the measuring tube, to a point typically 1.0 to 2.0 millimetres short of the centre point of the tube called the central axis (Figures 12-13) where and each measurement tube 10,11,12 will at its centre contain a copper wire 16 of typically 1.0 to 3.5 millimetres diameter, which will serve as a central axis marker and the length of this wire will determine the length of the tube that is actually used in the measurement process where the said copper wire 16 will extend symmetrically from the central point of the base of the said measuring tube and towards its other corresponding end, always with the copper wire lying at the central point of the tube, as a consequence of its quadrant 15 construction, and where the said copper wire will have accurately notched metric indicated 1 centimetre major graduations and 1 millimetre minor graduations, or other variations in units of scalar measurement using Imperial or other recognised unitary scale of linear measurement, that may be visualised during X- radiation or magnetic resonance imaging, as larger and smaller regularly spaced marks or notches, that serve to function as indicated measurable references for length, that in itself will be a known and stated parametric feature of the measurement tube(s), in addition to other values such as its internal / external tube diameter(s), cross-sectional diameter, encapsulated imaging volume, circumference, area, shape and angular configuration, and by way of example only where the interior fluid filled cavities 17 of the said measurement tube(s) 10,11,12 may contain an oil or other specified hydrogen containing medium that may be used to generate the magnetic resonance signal during Tl, T2*, T2, TI (Inversion) relaxation times used in magnetic resonance imaging or other preferred radio / frequency induced excitation / relaxation process(es) in the medium by the applied MRI pulse sequence(s), or with the use of a weak solution of a positive (iodinated) radiological contrast medium, a weak solution of a Gadolinium salt based magnetic resonance contrast medium, or a combination or substitution of the two former substances, that will function as both X-ray attenuator and magnetic resonance imaging relaxation agent for the solutions used, and which may be used concurrently with magnetic resonance and x-radiation imaging tests, and where in the design of the measurement tube, the chambers) of the tube(s) are filled with the solutions) and are sealed by an end plug(s) of a material that will seal and combine permanently with the materials) of the tube wall, to provide a seal that will be impervious to diffusion of gases from within, or air / other gas entry from the environment or chemical decompositions, and the said x and y axis linear measurement tube(s) 10,11 will be a straight tube(s), with other z axis linear test tools that will be mounted from the octagonal sockets 8 of the phantom support column(s) 6 will take the form of a short and long linear measurement tool 18,19, while the x, y and z axis non-linear measurement tube will have a singularity or plurality of lesser or greater curvatures or ranges of tortuosity, where the simplest curvature of a measurement tube(s) will include a single curve of shallow curvature 20, whilst others may increase in complexity by the inclusion of multiple curves with higher and lower levels of curvature 21-28, and where the essential design feature that triggers the mis-registration of image related positional co-ordinates and associated data within the image registration and correlation systems of the cross-sectional imaging modality or other imaging apparatus, is that the test tool reference tool must vary either intermittently or continuously in all three of the component x, y and z axes and that it is this feature that must be included in the said measurement tube design, for it to function as a primary parametric measurement verification tool, and as a secondary linear measurement verification tool, where specifically what is measured as a primary function of the test phantom is the course of the measurement tube(s) from one end of the measurement tube to the other, and where importantly the tools incorporated in the phantom sub-units must be such that they describe shallow or marked deviation(s) in at least two out of the three orthogonal planes, or intermediate oblique plane(s) in a continuous and / or variable fashion so as to produce image(s) that appear to be correct, but which in fact contains hidden positional and spatial errors and where corresponding value(s) of the reference markings indicated internally and externally on the universal imaging phantom may be compared against the value(s) derived by measurement using 3 -Dimensional and 2-Dimensional diagnostic image displays that calculate the values of length, cross-sectional diameters), area, volume or other measureable feature(s) of the measurement tube(s) as represented by the position variant individual image(s), series of images or screen capture(s) of the radiological phantom, such that the appearance of such discrepancies are indicative of instances where the modality specific accessory phantoms of the universal imaging phantom has required the scanner or modality software to perform at or beyond the resolving power of the manufacturer installed measurement software programs, and where the length(s) of these tubes may be variable in cross-sectional diameter(s) and the radii of curvature(s), but where in general more deviations in measurements from the scanner measurement software tools may be obtained by using smaller diameter(s), longer length(s) and higher curved variance (increased tortuosity) in the shaping of measurement tubes with multiple "antagonistic curves" that extend typically in one plane and then rapidly deviates by less than or greater than 90 degrees into another plane or direction of extension simultaneously across the x-axis, y-axis and z-axis, the latter of which defines the distance component of the measurements), and where maximal deviation is demonstrated by using a plurality of these described antagonistic curves on measurement tube(s), and where the tools themselves are designed with a range of variations of tool shapes by way of example only and for illustrative purposes as depicted in figures 18-28, and which are placed within in the phantom support column(s) 6 previously described, and where the shape of such curved measurement tube(s) are not restricted to the shapes herein defined or as a limitation in the combinations) of the said tool shape(s) placed in singularity or plurality of octagonal shaped or otherwise shaped vertical or horizontally arranged octagonal recesses 8 on either face of said phantom support column(s) 6, and where the said measurement tube(s) require to be accurately moulded, extruded or engineered into the range of prescribed bends of variable tortuosity, to enable the phantom to perform its primary function as a three axis variant measurement reference phantom enabling indicating the effectiveness and accuracy of 2-Dimensional and 3-Dimensional measurement software platforms to reproduce the parametric reference values of the phantom tools using nonlinear, curved and three axis variant line measurements).

A typically constructed measurement tube may be secured to the phantom support column(s) 6 attached to the base frame 1 by engaging with the mounting section 29 for location and fixing of the measurement tube(s) into the said octagonal recess 8 of the phantom support column 6 previously described (Figure 25), and where said mounting section 29 consists of a durable and strong thermoplastic or polymer that is moulded into a section with a head, body and base, with the head generally consisting of a larger diameter circular plate typically 3 millimetres greater than the diameter of the said attached measurement tube, the attachment of the said tube requiring to be both strong and durable in its nature, and where on the underside of the said head section and continuous with, is the body which consists of an octagonal block of greatest face-to- opposite face distance typically of 10 millimetres, and the length of the block typically 15 millimetres by way of example only and where said mounting section 29 would be located into the octagonal recess(es) of the socket(s) 8 of the phantom support column 6 and pushed in until contact with the underside of the head section would prevent further movement or further insertion, and the choice of an octagonal block 8 by way of example only, would provide a large range of positional variations (up to eight rotational positions) available to the tester at the time of setting-up of the tool, although it is appreciated that the shape of the locating holes may be preferred on the basis of another geometrical or otherwise preferred non-geometrical shape, and further where the said tube length multiplied by its actual cross-sectional area will derive what will be known as the "imaging volume", where the phantom support column(s) 6 is designed to hold a singularity or plurality of measurement tubes in the octagonal sockets 8 on each of its face(s) according to the preferences of the user, in any configurations) afforded by the positioning of the measurement tube(s) on the sectional face(s), the diameter(s) and length(s) of the chosen measurement tube(s), and where the number of vertical columns used, which may be increased during the testing procedure to accommodate a greater number of measurement tubes such that the consequences of doing this may result in difficulties in tracking the individual tubes on the generated test images, and where this introduces limitations in the measuring process and the interpretation of the generated images while using the manufacturer installed software to visualise singular rather than multiple or superimposed images of the measurement tube(s) 10,11,12 on the viewing platform of the imaging modality or scanner, thus in these cases increasing the margin of error to something most likely more significant, and offering no appreciable advantage(s) to the outcomes of the measurement process(es), image displaying an measurement accuracy.

The secondary role of the phantom may be facilitated by the use of additional iso-centric (central axis) and more peripherally orientated reference measurement tubes that may be applied, one on each face of said phantom support column(s) 10, 11 to assess for accuracy in the x and y axes across the iso-centre, centrally or more peripherally across the imaging field, allowing for linear length measurements across the field of view to be evaluated in conventional 2- Dimensional "point-to-point" imaging, which is generally current testing practice, and in this case, the middle of the reference measurement tube would be placed with the centre notch of the central wire at the centre of the measuring field (iso-centre), and in line with the intersections) of the axis lines on the faces of the said phantom support column(s) 6, and where the measurement tube(s) would be mounted in the clip extensions 9 along the x-axis on one face, and along the y-axis on the other face, so as to be in line and in turn with the x-axis and y-axis positioning laser beams of the scanner being tested.

The universal imaging phantom may be used to assess measurement accuracy of magnetic resonance imaging apparatus in a similar fashion to computed tomography (CT), with the exception that the modality specific accessory phantom may be preferred to be imaged in a water bath or tank to improve the quality of the image(s) obtained. Configuration of the universal imaging phantom would comprise a base frame 1 and phantom support column(s) 6 as previously described, onto which a singularity or plurality of said measuring tubes 10,11,12 used for reference and measurement, are receivable in a purpose built tank enclosure 30 prior to testing, and where said tank enclosure consists of perspex (RTM), acrylic or other transparent, strong, durable and non-magnetic material(s) that functions both as an enclosure for the said modality specific accessory phantom and also as a holding tank for the fluid medium contained therein, in such a manner that facilitates the mounting of the test phantom consisting of the said base frame 1 and measurement tube(s) 10-12, 18-28, within the said fluid or water environment that serves to enhance and amplify the image contrast levels between the image(s) of the interfaces of the internal and external components of the measurement tube(s) and the surrounding fluid medium. This allows for the measurements) of cross-sectional diameter(s), area(s), volume(s) and non-linear length(s) in any direction, and whereby using the described tank enclosure results in enhancement of the imaging process(es) when using magnetic resonance imaging techniques and where the fluid content of the tank overcomes the problems associated with Specific Absorption Rate (SAR) limitations, or in circumstances where it has become evident that the imaging of measurement tube(s) on their own and without the water enclosure results in a marked reduction in the received signal intensity of radio-frequency echoes generated by the measurement tubes solely and by, the magnetic resonance relaxation process(es), that results in inadequate signal strength that inhibits or prevents the initiation of the selected MRI pulse sequence(s) resulting in an unacceptably low signal-to-noise ratio, but where correction of the operating parameters of the scanner result in compensating for these limitations, thus allowing the scanner to perform the required magnetic resonance scan, measurement and generation of acceptably detailed image(s) which may further be enhanced by preference by immersion of the radiological phantom into the said water bath or tank enclosure thus markedly increasing the signal-to-noise ratio as a direct consequence of the high numbers of hydrogen nuclei in the water tank, and where as a result of imaging with a background of water enables greater detailed and contrasted images to be generated for easier visualisation of the walls of the measurement tube(s), as they appear as low signal (dark) areas or rings surrounded by brighter (higher signal fluid) on the outside and with brighter fluid against the walls of the measurement tube(s), and where the fluid tank enclosure 30 typically consists by way of example only, of formed perspex or acrylic polymer shaped into a flattened oval of typical wall thickness 10 millimetres thickness 34, and where the flattened part of the said tank enclosure extends typically for 252 millimetres at its resting base from end to end before it describes a curve at each respective end that continues to reach its apex laterally to a further 50 millimetres beyond the limits of the planar sections, or at the limits of the desired design parameters, to continue its curved or curvi-linear extension in an opposite and complementary fashion to the aforementioned course, where it becomes continuous with the raised or higher planar section of the tank enclosure, and further forming a thick perspex (RTM) rim 33 for locating with the cover plate 36 of the tank enclosure, where on the upper surface and at positions at 90 degrees to one another are positioned two non-metallic bubble or spirit levels 31 which function as longitudinal and transverse horizontal alignment indicators, and which are attached in order to provide a visual means of levelling status (Figure 26), while on its lowest surface and at each edge of the holder are screwed adjuster feet 32 made of perspex, acrylic or other suitable non-magnetic material, to enable the unit to be levelled during use, and such that said holder may by way of example only, have a width of 362 millimetres, height of 172 millimetres and a length of 475 millimetres, where at the edge of the said planar sections of the holder are arranged two 5 millimetres wide by 3 millimetres high locator ridges 35 that serves to guide the universal imaging phantom into the centre and along the length of the tank enclosure, and which runs the length of the planar section to the farthest face of the enclosure to a transparent perspex or acrylic planar end section of the one part of the tank enclosure. This is continuous with the farthest margins of the said holder, the said section forming an end to the said holder that is in itself sealed and continuous with the peripheral margins of the farthest end of the holder. The other end of the tank enclosure is open with a thick perspex rim 33 which is expanded and circumferential and forms a flange which is designed to extend to a point circumferentially 25 millimetres beyond the internal margins of the tank enclosure 30 at open end of the enclosure (Figure 27), and is machined to offer as perfectly a flattened surface for application as a seal 43 at a point 10 millimetres beyond the inner rim of the holder, and which at a line distance of 15 millimetres beyond the rim, and applied along the length of the flange, a series of holes 37 are drilled into the flange with a separation of typically 60 millimetres and with the diameter of the said holes being typically 7 millimetres, with the underside surface having embedded in it a threaded insert, the screw fastener recess 38 that will accept a 5 millimetre screw shank. The composition of the said embedded insert provides a protection for the fastening screws and being composed of ideally a non-magnetic and water corrosion resistant alloy that is easily machined and has a high tensile strength, thus forming the completed structure when engaged with the longitudinal members 2 of the base frame 1 of the said universal imaging phantom which may be progressively loaded between the locator ridges 35 and pushed to its farthest locatable position, then requiring at the open end of the tank enclosure 30 the placement of the cover plate 36 which consists of a transparent perspex, acrylic or other suitable material planar section, to engage with high conformity into the recessed edge of the tank enclosure 30 with its structured flange, allowing the structure to hold water or other higher signal generating fluid medium to the capacity of the tank enclosure 30, where it is required to be sealed by the said cover plate 36 prior to filling and which has by way of example only a 40 millimetre filling and drainage plug 39 that in itself consists of a threaded hole with an accompanying 50 millimetre diameter screw threaded plug of typically 20 millimetres thickness, and where the plug is machined to 40 millimetres halfway through the thickness, so as to be flush with the interior level of the cover plate 36, and by way of design offers a 5 millimetre wide ledge that is formed with the plug and which is fitted with a fibre washer or equivalent material 40, of by way of example only, an internal diameter 46 millimetres and external diameter 50 millimetres, and included to enable a good water-tight seal, and incorporates on the upper side of the plug and at its centre, also by way of example only, a 15 millimetre shaped recess for a 6 millimetre end of a hexagon key or Allen key (RTM) or equivalent, that may be used for tightening of the said plug into the body of the said cover plate 36, to be inserted and screwed in until the inner aspect of the plug lies flush with the inner layer of the cover plate 41 or extending into the tank cavity, and the outer aspect of the plug lying flush with the outer layer of the cover plate 42, and the said cover plate to positioned and located to engage into the recess of the body of the tank enclosure, in preparation of the insertion of the locking screws into the holes in the rim for the screw fasteners, and where the cover plate 36 has been designed to have slightly larger dimensions than the said section at its opposite end, and the underside of the section has a raised inner layer 41 that conforms closely to the contour of the interior rim of the tank enclosure 30, while the outer layer is wider than the corresponding rim of the body of the water enclosure, ensuring that a good water seal can be achieved, and further as a consequence of its design where around the rim of the said cover plate 36, there are 6 millimetre holes, by way of example only, drilled into the material and spaced every 60 millimetres apart, and positioned so as to be accurately in line with the hole(s) of the flange of the tank enclosure 30 below, and where inserted into these holes 37, by way of further only, are winged non-magnetic alloy 5 millimetre diameter screws of 25 millimetres length, having a raised collar above the end of the screw thread that acts as a washer against the perspex surface of the said cover plate 36 (Figures 28-29). Attached and continuous with the two inner edges of cover plate 41 is a soft, deformable and water resistant seal 43, that ensures that when the two sections are brought together, a watertight union is readily formed, such that when the screw fasteners are tightened down evenly and firmly a good water-tight seal is achieved, and when the whole assembly is stood up on its end and water or other suitable high signal generating fluid is poured into the assembly until it is full and purged of air, the said screw plug 39 can be inserted and tightened with the hexagon key until it is firmly within the body of the cover plate 36, and the tank enclosure is considered to be water tight. The completed assembly may then be accurately levelled prior to testing by adjustment of the adjuster feet levelling mechanism 32, of which there are typically four in number and which comprised of perspex (RTM) / acrylic or other suitable material section(s) attached to each corner on the underside of the tank enclosure, such that the assembly is by way of example only, a 30 millimetres long by 30 millimetres width by 5 millimetres thick interface plate which is permanently fixed to the perspex underside at each of the corners of the tank enclosure 44 and where attached to this, and perpendicular at the edges or periphery of the square is a 5 millimetre thick and 20 millimetre high square section that forms an enclosure around the square interface plate, where on the surface of this is placed and permanently fixed, another 5 millimetre thick square plate of 30 millimetres by 30 millimetres dimensions and where accurately at the geometrical centre of this plate typically is a 10 millimetre diameter hole, into which is inserted a 12 millimetre diameter by 25 millimetre length perspex (RTM) / acrylic or other suitable material support sleeve that has been tapped with a coarse screw thread to receive a corresponding 8 millimetre screw shank, which is further inserted / screwed a coarse threaded perspex (RTM) / acrylic or other suitable material threaded 8 millimetre diameter flat headed pin 45 of typical length 40 millimetres, where and at its lowest end, and at 5 millimetres from this end is an expanded 5 millimetre thick and 25 millimetre diameter finger adjustor, which has knurling on its outer edge to aid precision accuracy finger adjustments 46, and which may be levelled by individually screwing in / out of the adjustor feet 32 until the bubbles in the spirit levels 31 are at their respective centres, and indicating that the universal imaging phantom is levelled and ready to be used (Figure 30).

Other modality specific accessory phantoms of the universal imaging phantom may be mounted on the base frame 1 structure by means of an accessory phantom base plate 47 which enables releasable or fixed attachment of other modality specific accessory phantoms such as those used in computed tomography (CT) and nuclear (isotope) imaging (NI). The said base plate (Figure 31) is designed to provide extendable and multiple phantom configurations for increased functionality and testing across a wider range of imaging modalities. The modality specific accessory phantom is mounted by engaging the slotted section on the base of the accessory phantom into the correspondingly shaped locator groove 49 of the accessory phantom base plate 47. The said base plate comprises a base plate which may be constructed from perspex (RTM), acrylic or other suitably non-magnetic, radiolucent, durable, and transparent polymeric material consisting of an oblong plate typically 360 millimetres long by 198 millimetres width and 15 millimetres thickness with a partially triangulated groove (base towards the material of the plate) cut into the central longitudinal line of the said base plate from one end to the other and at its deepest point extending typically 7 millimetres into the material and with a base width of 20 millimetres 49 called the locator groove 49, thus forming a channel by which the complementary shaped interface(s) of an accessory phantom supporting block 51 may be located and releasably / fixedly secured, and by which means a range of modality specific accessory phantoms may be added in order to test other imaging modalities or machines. On each outer and uppermost edge of the base plate is a 4 millimetre thick lateral extension of 10 millimetres width that extends 360 millimetres from one end of the longitudinal line to the other, called base plate edge supports 48, of which correspondingly on the opposite lateral edge is another similar lateral and longitudinally extending extension, and where together they function to hold the base plate firmly in place once fitted into the base frame 1 thereby preventing the said base plate 47 from dropping through the frame or adopting an uneven rest position within the base frame 1, and where at various positions on the lateral surface of the longitudinal edges of the base plate, and spaced 40 millimetres apart, are 30 millimetre deep holes 50 perpendicularly into the material of the base plate 47, which correspond to the spacing of holes on the lateral aspects of the longitudinal members 2 of the base frame 1, and by which an unthreaded nylon or other suitable non-magnetic material headed locking pin may then be placed into each of the two holes 50 to allow the base plate accessory module to be fixedly or releasably and / or variably secured together with the base frame 1, and where the diameter of the pin(s) would typically be fractionally below 5 millimetres and of length 30 millimetres and with a typical head diameter of 15 millimetres and shoulder thickness of 5 millimetres.

A similarly designed module that is designed to slot into the said accessory module base plate 47 is called the accessory phantom supporting block 51 which comprises a block which may be constructed from perspex (RTM), acrylic or other suitably non-magnetic, radiolucent, durable, and transparent polymeric material which is typically 360 millimetres length, 20 millimetres width and 164 millimetres height, the base of the block 52 being expanded in a triangular shape so as to closely interface with that of the longitudinal groove of the accessory phantom base plate 47 where at its most expanded part, the footprint is typically only 19 millimetres width and 360 millimetres length, and where at the middle point of the support blocks' height is a similar type of inverted triangular groove on each face of the supporting block which are typically 20 millimetres width by 360 millimetres length and 5 millimetres deep at their greatest depth 53 and where at a point 157 millimetres to the apex of the support section, the width of the block reduces by few millimetres on either edge and then expands to a 19 millimetre base of an inverted triangle that continues along the 360 millimetre edge of the block, and forms an identical triangular based locater groove 53 of the accessory phantom base plate below 47 (Figure 32).

The range of measurement accuracy testing may be expanded by use of a modality specific accessory phantom for z-axis testing of computed tomography (CT) 54 which comprises an accessory phantom whose method of securing to the accessory phantom base plate 47 follows a similar footprint to that of the accessory phantom supporting block 51 with the exception that there is only one triangular expanded foot section 52 on the said accessory phantom. The base of the said accessory phantom (Figure 33) is expanded in a complementary triangular fashion so as to closely interface with that of the longitudinal locator groove of the accessory phantom base plate 49, where at its most expanded part, the footprint is typically only 19 millimetres width and 360 millimetres length, and where the opposite and uppermost end is a normal square edged face, and the tool module has four horizontal limbs which extend from a point originating from the central line of the vertical section of the tool holder that interfaces longitudinally with the locator groove of the accessory base plate 49, and where each tool limb is oppositely mounted and separated by specific height intervals and each limb on one particular side is twice the width of its neighbouring limb 55, the first limb originating from a point 20 millimetres vertical from the floor of the accessory module base plate 47, and is by way of example only, 70 millimetres long and positioned at 90 degrees clockwise to the central vertical line, with the second limb originating from a point 40 millimetres vertically from the base along the central line and at 270 degrees clockwise for typically 120 millimetres, the third limb originating from a point 60 millimetres from the base along the central line and at 90 degrees clockwise for typically 120 millimetres and the fourth limb originating from a point 80 millimetres vertically from the base along the central line and at 270 degrees clockwise for 70 millimetres, with each of the limbs having a sectional thickness of 20 millimetres and at each lateral end, and being symmetrically placed and 20 millimetres from the lateral edge with a 5 millimetre drilled hole that extends longitudinally for the 360 millimetres of the length of the limb, and where into each of these holes is accurately placed a 4.5 millimetre diameter rod of length 360 millimetres length with radio-opaque markers spaced at 5 or 10 millimetres or other preferred sub-division of length interval(s) for the whole length of the rod 56, and in which the rod is placed firmly into the full length of each of the limbs until the ends are flush with the edges of the drilled hole(s), and where this same condition holds for the other four drilled holes incorporated into the said accessory phantom body and other limbs, and whereby the result of this arrangement is that each shorter opposing limb will be 50 millimetres laterally from the central reference plane of the test and the iso-centre of the field of view (FOV) of the CT scanner and 30 millimetres vertically from the reference measuring rod 56 at the centre of the tool, such that the reference point(s) of the tool may be placed in the iso-centre of the scanner for maximum measurement accuracy or in any of the quadrants of the scanner field of view, and where the longer limbs will be 100 millimetres laterally and 30 millimetres vertically from the reference point, and the cylindrical rods will be used to generate reference image(s) in each of the orthogonal planes when imaged on the computed tomography (CT) apparatus, and where the images produced in the axial 57 (Figure 34), sagittal 58 (Figure 35) and coronal 59 (Figure 36) planes respectively, have definite spatial relationships for that plane, and measurement verification in all three planes can be evaluated accurately.

The combination of the base frame 1, accessory phantom base plate 47, base plate edge supports 48, and modality specific accessory phantom for z-axis testing of computed tomography 54, when imaged by the preferred Computed tomography (CT) imaging machine generates image(s) or a volumetric image data set which when displayed is viewed as five lines of linearly orientated and regularly spaced radio-opaque markers in the directions) of the chosen x, y, z orthogonal or oblique axes, and the derived volume data block or generated plurality of sectional image(s) serve as linear distance reference markings on the said image(s) and function to evaluate the ability of computed tomography (CT) apparatus to accurately register and spatially represent image(s) of the said modality specific accessory phantom in all orthogonal planes of imaging and to generate accessory phantom test pattern image(s), such that the specifically positioned and distanced linear dotted image(s) obtained can be used primarily to evaluate the scanner software / hardware to accurately image and display a single and linear reference line composed of radio-opaque dot image(s) in any preferred orientation(s) and being independent from the requirement of being imaged along an x, y or z axis relative to the scanner vertical, horizontal and longitudinal axes, such that the radiological image of the universal imaging phantom creates a pattern of linear and parallel dotted images that may be viewed progressively using the 3-Dimensional software by increasing the sectional thickness of the viewed image until the next line of linear dots are viewed, until all of the reference lines contained in the said accessory phantom are displayed singularly or in multiples, and where evaluation of said reference lines evaluate the ability of the scanner to accurately display parallel reference lines at the known distance(s) or slab thickness(es) of the visualised said accessory phantom (parallelism) in any given direction and in a linear fashion (translational linearity), and where the said accessory phantom as a consequence of its design incorporates regularly spaced dot references of a singularity or plurality of diameter(s) that perform the secondary function of the tool by the provision of a means of verifying linear distance, where the spacing of the dot(s) may be measured in metric, Imperial or any other recognised or calibrated unit(s) of length, and where the evaluation of single or multiple reference line(s) contained within a the generated scan image / data volume, can be used to evaluate and quantify as a primary function of the accessory phantom to test the capacity of the CT apparatus and operating software to accurately display and measure block or slab thickness and the capability to display a uniform sectional rectangle of target image that is contained within the entirety of the said scan / image data volume, and which may be compared, calibrated or measured with particular regard to distance(s) along the complete length of the reference line(s), distance(s) between single or multiple dot(s), perpendicular distance(s) between single or multiple dots, or between two or more of the imaged reference lines throughout the whole of the imaged said accessory phantom contained within the said scan / image data volume, with derived measurements) or distance(s) being compared against the known reference value(s) of the particular phantom sub-unit(s), thus allowing the scientific test person to create a fast and accurate assessment of the scanner software performance with regard to 2-Dimensional "point-to-point" or line measurements) in any orientation, regularity of the CT scanner data matrix and parallelism of the reference image contained in the volume of CT scan and image data.

The image(s) of said accessory phantom may also be used secondarily as a means of confirming and validating linear measurement of length along horizontal, vertical, oblique and curved imaging planes, such that the said accessory phantom image(s) and their respective known reference measurements) may be compared against the measurements generated by 3- Dimensional and 2-Dimensional image manipulation and measurement software package(s) that are ready installed on all commercially available computed tomography (CT) apparatus, such that the said accessory phantom(s) when configured and imaged enables the specific testing of an imaging modality and its image viewing software to generate reference image(s) in any plane(s) of interest, and where the assessment of the accuracy of computerised tomographic imaging apparatus requires the use of the CT reference accessory phantom, in a required position in the imaging apparatus and imaged with a suitable computerised tomographic imaging technique(s); forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool enables the at least one measurement to be used for comparison of the measurement accuracy of the manufacturer installed measurement tool software, and which may be compared against the known value(s) of the image(s) generated, with particular reference to the length(s), diameter(s) and volume reference^) contained in and on the said accessory phantom(s), and indications of the efficiency of the scanner to do this, by way of example only, may be seen from the geometrical layout of the phantom sub-unit images in the axial, sagittal and coronal illustrations (Figures 34-36), where in the axial projection (Figure 34) which shows said cylindrical measurement rods 56 in relationship proximity of all other peripheral measurement rods in the opposing and staggered limb arrangement to the central reference rod within the body of the said accessory phantom, along which when imaged using computerised tomographic apparatus will produce image(s) of the rods with radio-opaque scalar markings of regularly spacing and sizing as five sets of parallel lines which when viewed in any plane will give a constant measurement relationship for images generated on the scanner and viewed as 2-Dimensional and 3-Dimensional image(s) for orthogonal projections and volume image blocks, and thus testing the integrity of the scanner to image the radiological phantom and to generate images that are both accurate in terms of spatial relationship^) and position, and further allowing assessment of the capability of 2-Dimensional and 3-Dimensional display platforms and their software measurement tools to produce measurement value(s) that match the reference value(s) of diameter and length contained within the design of the said accessory phantom, and also the capability of the imaging and display system to display the parallel and regularly spaced markers of the phantom in a manner that is exactly or closely matched to the construction of the phantom.

Another use of the universal imaging phantom is for the validation of measurement accuracy for imaging apparatus used in digital subtraction angiography (DSA) and radio-fluoroscopic (RF) imaging and which a typical phantom configuration would comprise a base frame 1 onto which a number of shaped linear and non-linear measurement tube(s) 10-12 may be fixedly or releasably connected and imaged by the imaging modalities specified, and where the image(s) generated will contain the relative parametric values indicated by radio-opaque image markers contained on the internal and external aspects of the said measurement tube(s) and which function to indicate on the said image(s) the apparent values of diameter(s) and length(s) of the said accessory phantom and the value(s) of which may be compared to the actual or reference value(s) contained on and in the said accessory phantom, thus allowing an estimation of accuracy of measurement method in different imaging planes, magnification at a given distance of object to intensifier head, and effects of distortion when measuring linear and non-linear structures with a planar imaging method, and where a range of linear and non-linear measurement tube(s) may be used to evaluate the capabilities of the imaging system to produce image(s) that are both minimally distorted and accurate with regard to definition of internal and external boundaries and profiles of the radiological phantom.

Another modality specific accessory phantom of the universal imaging phantom is one used for nuclear (isotope) imaging (NI) and which typically comprises a base frame 1, an accessory module base plate 47, and the modality specific accessory phantom for measurement of nuclear (isotope) imaging 60 which may be engaged into the accessory phantom base plate 47 in the manner previously described, and where the accessory phantom has typical physical dimensions of 360 millimetres length, 20 millimetres thickness, and 157 millimetres height, with the phantom sub-unit having positioned horizontally at its midpoint two locator grooves similar to those for engaging modules on the accessory phantom base plate 47, and similarly where the locator grooves serve to hold and position more than one modality specific side mounted accessory phantom for nuclear (isotope) imaging 69 for more elaborate testing with Single Photon Emission Computerised Tomography (SPECT) and Positron Emission Tomography (PET) scanner units, and also where at two points 20 millimetres from the apex of the vertical section, and 20 millimetres from the base of the accessory phantom supporting block, and in line with the central bisector, are round cavities extending from one surface and into the material of the module, and parallel distally to a point of emergence at the other end of the module and parallel to the longitudinal line of the module, where into this cavity is accurately placed and fed a 14 millimetre square insert 61, by way of example only, or other preferred shape, that is made of a high attenuation material such as lead or steel, or other suitable material, until it emerges at the remote end of the channelled out square cavity of the tool block for the full 360 millimetre length of the tool, with the insert itself having a round channel of typically 10 millimetres diameter at its geometric centre, and extending throughout the length of the insert where along the three points of the circular aperture and spaced regularly at typically 40 millimetre intervals, or other preferred length, are pin-hole apertures 63 of typically 0.5 millimetres diameter, or other preferred diameter(s), along the length of the measurement tool, and placed securely into this lead insert 61 is a cylinder 62 made from steel and of typically 9 millimetres outside diameter and 7 millimetres inside diameter and 350 millimetres in length, with larger typically 1 millimetre holes drilled, such that along the length of the insert and corresponding to the pin-hole apertures 63 of the lead insert 61 at 0 degrees, 90 degrees, and 270 degrees are small diameter apertures to allow the radiation to exit, and due to the design is made to carry and seal a plastic isotope tube 67 containing the radioactive substance, typically a metastable salt of Technetium (Tc99m), but other isotopes may be used according to preference, (Figures 37-39), and ensuring that the diameter of the pinpoint apertures is small enough to allow a certain dose rate of gamma radiation photons to pass through so that a suitable pinpointed area may be produced on the scintillation crystal of the gamma camera, and where the markers on the external faces of the measurement scales 64 typically run from negative multiples of 40 millimetres at one end, for example -160 millimetre, -120 millimetres, -80 millimetres, -40 millimetres to zero at the centre of the tool, then to a positive multiple of 40 millimetres at the other end, for example 40 millimetres, 80 millimetres, 120 millimetres and 160 millimetres, and where at each of the 40 millimetre points is an aperture for the gamma radiation to be emitted simultaneously from the same locus, but from three different directions, and such that the one end has a lead block locator pin 65 that fits into the lead section of the imaging tool to allow the steel cylindrical tube insert 62 carrying the plastic isotope tube 67 to be located accurately into position(s) to ensure that the pinpoint radiation emitted is of limited and reduced intensity so as to be registered on the scintillation crystal as a small "hot spot" of recorded high radiation activity (Figure 43), and where also at each end of the cylindrical insert is a screw thread to allow the fitment of two 6.5 millimetre diameter headed steel screw plugs 66 to cap off each end of the cylinder once the loaded insert is placed within it (Figure 39), and where a further disposable 5.0 millimetre transparent plastic insert of 340 millimetres length is used to hold the isotope during testing, using a plastic tube of typically 3 millimetres internal diameter 67, and where the administration of the isotope is carried out behind lead bricks in a dispensing area dispensing a prescribed activity, for example 10 MBq (MegaBecquerels) drawn up into a lead shielded syringe, and using this level of activity as a balance to provide enough radioactive disintegrations to register a "hot spot" of radiation activity on the scintillation crystal so that the acquisition time to register typically 200 Kilocounts is in the time frame of five minutes, rather than in contrast as having a higher level radioactive source (150 MBQ) in the tool that is emanating much higher doses of gamma radiation that may be advantageous for shorter acquisition times, but of limited use because the intensity of the radiation beams from the apertures produce hot spots of larger and indistinct diameter(s) such that they overlap with the hot spots of the neighbouring aperture(s), at a 40 millimetre distance separation, or where they create difficulties in defining the centre(s) of the hotspot on the acquired image(s), thus likely causing invalidation of the accuracy of any measurements derived from use of the said accessory phantom, or at least limiting any inferences or validations of measurements) based on the images produced, and by which the use of a hypodermic needle delivers the isotope solution into the bottom of the plastic isotope tube 67 which is in a lead shielded cover and the fluid level is increased with coloured saline to a marked level on the outside of the tube, the coloured saline serving to identify any leaks from the tube assembly and allowing identification of the fluid level as the plastic tube is filled to level, and where the coloured fluid level can be easily seen to rise along the inspection window of the lead syringe shield so that once the correct level has been achieved the end can be sealed off with a plastic cap and rubber seal 68, which is engaged with the top screw threaded end of the plastic isotope tube and then it is withdrawn from the lead syringe shielding thus allowing the plastic isotope tube 67 to be placed into the steel cylindrical tube 62, and the screw caps 66 screwed to the closed position and then fed into the lead housing of the accessory phantom 60 until it engages into position with the lead block locating pin 65 such that the said accessory phantom is ready to be located into the accessory phantom base plate 47 and main frame 1, and secured by suitable locking pins and the completed construction is ready for measurement, except in cases where multiple sources are required to be used for evaluation of more complex scanning procedures that may involve 360 degree tomographic plane measurement assessments.

The functionality of the modality specific accessory phantom for nuclear (isotope) imaging may be further progressively increased to include 1 or 2 modality specific side mounted accessory phantoms for nuclear (isotope) imaging 69 which may be used to support a greater ) number of steel cylindrical tubes 62 carrying a plastic isotope tube 67, which is typically 97 millimetres width, including the 7 millimetre depth of the locating groove, by 360 millimetres length, by 20 millimetres thickness (Figure 40), and where the said accessory phantom may be engaged into the modality specific accessory phantom for z-axis measurement of nuclear (isotope) imaging 60 in the manner previously described, and whereby the base of the said accessory phantom is shaped and expanded into a triangular wedge 52 so as to closely interface with that of the locator groove 53 of the said accessory phantom, such that its most expanded part, the footprint is typically only 19 millimetres width and 360 millimetres length, and at its extreme lateral aspect, the lead insert 61, steel cylindrical tube 62, pin-hole apertures 63 and plastic isotope tube 67 are identically positioned within the cavity of the accessory module in order to give an identically arranged and positioned configuration as with the other isotope carrying components within the body of the said accessory phantom for z-axis measurement of nuclear (isotope) imaging 60 and other side accessory phantom(s) for nuclear (isotope) imaging 69 so that the pin-point apertures 63 may be used in a singularity or in a plurality to provide a range of combination(s) with another three possible additional modality specific accessory phantom(s). In these types of configuration, more detailed examinations may be performed on tomographic (the imaging technique of producing sectional images by the rotation of diametrically opposed or relatively offset scintillation detectors) about a fixed axis that indicates during imaging the highest to the lowest levels of radioactivity in the imaged volume of interest, or Single Photon Emission Computerised Tomography (SPECT) or Positron Emission Tomography (PET) type examinations, and where the completed universal imaging phantom configured for z-axis measurement of nuclear (isotope) imaging 60 and the engaged side mounted accessory tool 69 is illustrated (Figures 41), and where up to three loaded plastic isotope tubes 67 may be placed in any desired configuration, to the most complete variation using four loaded tubes by the addition of another side mounted accessory tool 69 section is illustrated (Figure 42) which will enable more complex evaluations to be made, for example, tomographic function and distance measurements in the z-axis, in addition to 2-Dimensional measurements, which shows the spatial relationships between the image(s) of each of the pinhole apertures as "hot spots" of signal intensity of the smallest diameter required across the imaging area of the scintillation crystal to give a small dot of typically 2 millimetres diameter and each centre of the hot spot to the centre of the next typically be close to 40 millimetres, with a separation of 100 millimetres between each row of imaged hot spots (Figure 43).

Another modality specific accessory phantom for use with computed radiography (CR) may be used to produce test image(s) whose structural design produces a range of parametric reference value(s) as part of the image. This may be used to evaluate computed radiography (CR)imaging apparatus, picture archive and communications systems (PACS) and networked image transfer systems and teleradiology systems using digital imaging and communications in medicine (DICOM) or other accepted image transfer standards. The universal imaging phantom for computerised radiography (CR) typically comprises an modality specific accessory module for measurement of computed radiography (CR) 71 (Figure 44) which may be fitted into the base frame 1, by a number of locating holes drilled perpendicularly into the sides of the tool and separated by 40 millimetres for releasable or fixed securing with retaining pins inserted into the recesses 80, such that once the accessory module is secured into the base frame 1, short and long linear measurement tubes 18, 19 may be added for linear measurement testing of images produced by the CR image production process and forming the basis for assessment of measurement accuracy of image(s) transferred by networking and teleradiographic image transfer processes. The module consists of an imaging section constructed from perspex (RTM), acrylic or other suitably non-magnetic, radiolucent, durable and transparent material and arranged by example only, as an oblong block of typical dimensions 360 millimetres length by 198 millimetres width and 20 millimetres thickness, where on the underside of the block is an arrangement of radio-opaque markings 73 that when viewed from above describe a number of functional markings, lines and edge indicators, the lines forming a square on the bottom aspect of the base of typically 350 millimetres length by 190 millimetres width, where a diagonal line 74 is drawn from each corner to form four triangular sections, another two lines are drawn from the midpoint of each edge to the centre of the base dividing each of the triangular sections into two, this in itself forms smaller triangular areas 72 across the base area , where along each of these bisecting lines and extending to the edges of the plate are linear scales measured in metric or Imperial sub-divisions of a metre or a foot respectively, so that typically in the case of a metric scaled base, these subdivisions would be in millimetres and centimetres and extending from the centre point at zero radially to their respective maximum values, and in the case of an Imperial scaled base, these sub-divisions would be in inches or less, and where at each of the four corners of base and at a point typically 90 millimetres above and below the longitudinal (or horizontal) centre line, and 175 millimetres to the left and right of the transverse (or vertical ) centre line are four corner identifiers 73, each set comprising right angled lines of typically 30 millimetres length serving to delineate the corners of the base for an X-ray field collimation area test (or area of defined X-radiation exposure), and where on the base there is defined a circle 75 at the geometrical centre of the accessory module for the vertical central ray of the X-ray tube to be centred prior to radiographic exposure, and which serves as a point of centring for the applied X- radiation beam to the said accessory phantom for measurement of computed radiography (CR) images 71. This ensures minimal distortion and parallax in the image(s) generated, and where in every other triangular section of the module 72, and inlaid into the polymer substance are functional test units for assessment of image distortion.76 in the form of a geometrical shape module to evaluate distortion in an image, measurement of resolution and Modulation Transfer Function (MTF) 77 in the form of a line pairs per centimetre module, sensitometric type testing of the image plate recording system 78 by use of an incorporated wedge filter, and symmetrical square references for further image distortion evaluation 79, and image contrast references, where each of the densities of the squares from number 1 to 8 has a respective thickness and calibrated effect of reducing radiographic densities across the area of the imaging plate, such that if the contrast level(s) were measured from 1 to 8, the measurements when obtained and plotted on a graph would give a linear relationship of contrast index against the square reference number, and where such testing may be carried out using an added filter equivalent to 1 millimetre of copper to harden the X-radiation beam and absorb lower energy wavelength radiation that may reduce the image contrast levels in the image(s) generated, using prescribed or standardised test exposure(s) at a specified (focus to image plate distance) to reduce the effects of variations) in image quality as a result of differences in X-radiation beam characteristics, and further where the imaging plate(s) used for recording the latent or stored image(s) are solely used for quality assurance (QA) testing and read or interrogated using a specified computed radiography imaging plate reader of known performance.

Another modality specific accessory phantom for computed radiography is the tubular version 81 and which comprises an oblong frame used for the supporting of measurement tube(s) used in the accessory phantom 82 that may be inserted into the base frame 1, and whose dimensions are typically 408 millimetres long by 198 millimetres width, and 20 millimetres thickness, and where the frame is typically divided unequally into three sections, the first section having its point of origin 123 millimetres from the vertical edge of the left sided column and bounded by a vertical column extending from one longitudinal edge to another, forming a section on the left side of the construction called the main vertical window of the accessory module 83, where situated at the midpoint of the vertical column is a horizontal column typically 20 millimetres square, which extends to join with the transverse column of the right side of the frame construction, the horizontal column dividing the remaining space into two equal portions, a lower section called the lower horizontal window of the accessory module 84, and an upper section called the upper horizontal window of the accessory module 85, and where by way of example only, the horizontal column would originate from a point 79 millimetres from the base of the section, the main vertical window would be 160 millimetres transversely and 113 millimetres longitudinally, and the two divided smaller sections would be 69 millimetres transversely by 235 millimetres longitudinally (Figure 45), and where at various positions on the lateral surface of the longitudinal edges of the frame, and spaced 40 millimetres apart, are 30 millimetre deep holes 50 perpendicularly into the material of the base plate which correspond to the spacing of holes on the lateral aspects of the longitudinal members 2 of the base frame 1, where an unthreaded nylon or other suitable non-magnetic material headed locking pin may then be placed into each of the two holes to allow the base plate accessory module to be fixedly or releasably and / or variably secured together with the base frame 1, and where said frame has a number of retaining clips 86 (Figures 46-47) for holding specified diameter linear measuring tube(s) in longitudinal, transverse or oblique planes (Figure 48), and where by way of example only, the typical diameter(s) for the transverse measurement tube(s) 87 would be 20 millimetres and the tube length 140 millimetres for the left hand vertical tubes, and where this section would typically incorporate three of the oblique measurement tubes 89 of differing cross-sectional diameter(s) and length(s) of imaging column, and in the upper right hand section of the frame that carries the longitudinal measuring tubes 88, the tube diameters) would typically be 25, 20, - 15 and 10 millimetres cross-section and of tube length 215 millimetres, and would incorporate four measurement tubes of differing cross-sectional diameter(s) and length(s) of imaging column, the lower right hand section carrying the obliquely mounted measuring tubes 89, would typically require similar diameter measurement tubes of 20, 10 and 5 millimetres cross-sectional diameter(s) and of typical length variations between 235 -160 millimetres length, but with different lengths of imaging column, and by which the mounting or securing of these said measurement tube(s) in their defined and relative positions, is by the provision of wedges shaped into the construction at certain positions in the construction that hold the supporting clips, and whereby the final construction once assembled can be mounted into the base frame and secured into position with the retaining pins located into the recesses 80 on the said accessory phantom 81, where each of the measuring tubes will have an imaging volume of fluid contained in the body, and the column length of each tube can be varied according to the preferred choices, such that typically, in the left hand section a 140, 100 and 60 millimetres length selection are used, and in the top right hand section, typically 215, 175, 135 and 100 millimetres length selection is used, and in the lower right hand section, typically 235, 175, and 100 millimetres length selection is used and illustrated in plan and side elevational views respectively (Figures 48-49).

Another more specialised use of the universal imaging phantom is in the testing of combination scanners for computerised tomography (CT) and nuclear (isotope) imaging (NI). The universal imaging phantom is configured to include modality specific accessory phantom as previously described for both types of imaging modalities 90 and typically comprises a twin modality configuration involving the typical setup for measurement of computed tomography (CT) 54 using reference measurement tube(s) 10, 11, 12 mounted on the phantom support column(s) 6, which in turn are mounted on the tool base frame 1, and also using simultaneously the accessory phantom base plate 47, isotope loaded modality specific accessory phantom for z-axis measurement in nuclear (isotope) imaging 60, and isotope loaded modality specific side mounted accessory phantoms for nuclear (isotope) imaging 69, and where the said base frame 1 is loaded with the accessory phantom base plate 47 and modality specific accessory phantom for z-axis measurement in nuclear (isotope) imaging 60 and the preferred number of modality specific side mounted accessory phantoms for nuclear (isotope) imaging 69 such that the configuration will provide single, multiple plane and tomographic plane linear transverse and longitudinal measurements, and with the further addition of a phantom support column at one end (towards the CT scanner or otherwise) will allow the attachment of a singularity or plurality of preferred non-linear and linear measurement tube(s) 10, 11, 12 for the evaluation of CT measurement performance, and where the base frame 1 can accommodate easily for the addition of two such phantom support columns 6 in addition to the said accessory module base plate 47, said accessory phantom for z-axis measurement in nuclear (isotope) imaging 60 and said side mounted nuclear (isotope) imaging accessory tool module(s) 69, given by way of example only in this type of configuration, and where typically, a single phantom support column 6 and z-axis measuring tube(s) 12 is matched with a fully loaded tool modality specific accessory phantom for the z-axis measurement of combined nuclear imaging and CT imaging apparatus (Figure 50- 51), and such that the universal imaging phantom with its configure modality specific accessory phantoms in its most basic embodiment is designed to compare and validate known value(s) of length measurements) in image(s) generated by the two specific imaging modalities, and defined by the internal and external markers contained within the construction of said measurement tube(s), to compare with measurements) derived from the display and image measurement tools, thus evaluating the capabilities of the said imaging modality to measure and generate measurement value(s) that either match or are deemed acceptable levels of accuracy. Such parameters of measurement include reference to the known value(s) of cross-sectional diameter(s), area(s), volume(s) and length reference(s) that are contained internally and externally in the design and configurations) of the universal imaging phantom.

Another accessory phantom of the universal imaging phantom is a measurement accuracy correction phantom for computed tomography (CT) which may be used to provide a 1 centimetre reference matrix that may be recorded below the phantom being imaged such that the image of the said matrix is integrated with image of the preferred modality specific accessory phantom but able to be accessed if required by dropping the viewing plane to a point below that of the said accessory phantom. The modality specific measurement accuracy correction phantom for computed tomography (CT) 91 is designed to work in conjunction with the base frame 1 and measurement tube(s) assemblies 10, 11, 12, or in isolation underneath the object or region(s) of interest, and by way of example only, where the measurement accuracy correction phantom may be integrated unobtrusively into the body of the imaging table of the computed tomography (CT) apparatus, and where the construction of the said measurement accuracy correction phantom is made from perspex (RTM), acrylic or other radiolucent and non-magnetic material frame which may be shaped into any desired shape but by way of example only an oblong shape as it is more suited to the design of current CT scanner tables, and where the said measurement accuracy correction phantom comprises a number of not less than two, and typically not more than five planar single sections, in order that the added inertia to the table is minimised, and that table indexing and movement characteristics are not altered, and where each complete sectional layer 92 is typically of such a thickness that a 2 millimetre, 5 millimetre, 10 millimetre or otherwise diameter hyper- dense sphere of low to moderate x-ray attenuation can be embedded into the middle of the section at a plurality of appropriately positioned and linearly related loci across the surface of the material to form lines of reference on the said section(s) (Figures 54-56), and where the separation of these hyper dense spheres is typically 10 millimetres longitudinally and transversely from each of their respective centres so as to form a 10 millimetre square matrix covering the larger aspect of the upper surface of the section (Figures 54, 58), and where by way of example only, the spheres are arranged such that the first and last sphere is 2 millimetres diameter along the longitudinal length and the transverse width of the whole of the said measurement accuracy correction phantom in that specified layer 93 and all other layers except the middle layer 94 which is different in that it is composed of two separate longitudinal lines at the most lateral or outer points of the construction and the reference matrix, with each said line having embedded in them 10 millimetre diameter hyperdense spheres 95 of low to moderate x-ray attenuation which are offset by 10 millimetres distance and generally separated by 20 millimetres distance. The rest of the longitudinal lines at all other levels are composed of 2 millimetre diameter spheres and with 10 millimetres separation to give general continuity throughout the correction matrix. The function of the 10 millimetre hyperdense spheres are for reference purposes and are present only to delineate the most lateral or outer edge of the correction matrix. The use of an additional numbers) of similarly sized and shaped sections placed squarely, closely and fixedly to the said section(s) will provide an overall thicker sectional construction and correction matrix 96. On the one or both ends of the sectional construction is a section containing a range of diameter spheres including higher diameter spheres to function to give reference to the electronic cursor measurements of known diameter planar disks of 25 millimetre diameter 102, 20 millimetres diameter 103, 15 millimetres diameter 104, 10 millimetres diameter 105, and 2 millimetres diameter. Measurements of disk diameter and thickness of the disk may be performed using the imaging modality measurement tools and these should be accurate or within acceptable levels of performance.

The image of the correction matrix is based on a 1 centimetre cube and at its most basic the distance relationship between the centres of a single sphere to the centre of the next should be 1 centimetre in longitudinal, transverse and vertical directions. If the point of reference was to be taken from the centre of one sphere to the centre of another obliquely, then the distance would be the square root of 2 which is 1.414 centimetres. There are no direct references to actual triangles within the structure since the correction metric can only function from 1 centimetre cubes or from multiples thereof in any direction. Any reference made to geometrical relationships are purely in the interests of quick calculation of length, and by way of example only, a 3 centimetre line of reference drawn across four spheres and a 4 centimetre line drawn across five spheres will have a line that joins them that passes through six of the spheres obliquely and will have a length of five centimetres. The coronal image illustrates how lines of reference length can be drawn for measurement comparison purposes (Figure 54, 58). The measurements are achieved using a point to point line between the centres of the spheres and extending to the desired centre of the sphere as a point of reference. Longitudinal, transverse and vertical distances may extend to any whole number value accommodated by the physical dimensions of the correction matrix, while measurements performed obliquely across spheres always have odd numbers and are depicted as 3 centimetre longitudinal axis line 97, a 5 centimetre longitudinal axis line 98, a 7 centimetre transverse axis line 99, and a 5 centimetre oblique axis line 100 (Figure 54). On the first or uppermost of these sections is provided at the one end of the construction, a reference disk and line section 103 that is built into the construction and provides ready access to references, typically a 25 millimetre reference diameter disk 104, a 20 millimetre reference diameter disk 105, a 15 millimetre reference diameter disk 106, a 10 millimetre reference diameter disk 107, and a 2 millimetre reference diameter disk. The reference section also provides lines of reference length, typically a 3 centimetre transverse axis reference line 109, a 5 centimetre transverse axis reference line 110, and a 7 centimetre transverse reference line 111.

In order for the relationship between image construction and measurement to be free from spurious or incidental errors, it is important that any measurement accuracy device or measurement software program is able to operate either within the premise of being acquired at the same time as that of the region of the imaged anatomy, or that any measurement accuracy calculations are derived from preferably first order calculations from the raw data or the first generated series image data. This will ensure that other external sources of error are kept at a minimum. The images generated will include the anatomical region of interest that will be seen to be lying on the imaging table. The reporter will orientate the anatomical structure or region of interest into the preferred plane of interest and then select a viewing platform and image measuring tools to assess the cross-sectional diameter and length of the area of interest. The manufacturer software image measurement and manipulation programs available on the cross- sectional imaging apparatus generally fall into direct measurement of axial, oblique or lateral images, viewing and image manipulation of axial, sagittal, coronal or derived oblique plane of said imaging projections). These may be further imaged and manipulated by curved reconstruction, multi-planar reconstruction (MPR) and maximum intensity projection (MIP) imaging platforms. The values of cross-sectional diameter and length that may reported from these platforms may in themselves be deviant due to a range of underlying reasons, but all may be verified by the inclusion of the measurement accuracy correction tool. This is because the construction of the tool has incorporated into its design an imaging matrix of 10 millimetres square in all directions and for a depth of typically sixty millimetres thickness.

The imaging matrix is placed on the table as part of the imaging table components and other supporting support sections are added above and below the level of the measurement correction accessory tool, so that the patient is made to be comfortable during the CT acquisition process. Ideally, the measurement correction matrix should be mounted within the imaging table 112 so as to be part of the table configuration (Figure 52, 53). The patient is placed on the scanner 113 in a position on the imaging table to include the region of anatomy under investigation within the available area of the measurement correction matrix. The patient is then translated through the scanner until all areas of the anatomy have been scanned and imaged.

When the reporter has viewed and targeted the area of interest on the display screens of the modality workstation, the measurements) may be made using the electronic callipers of the reporter measurement tools, and a value for cross-sectional diameter and length may be generated as a linear value. This may in itself may be accurate, but measurement inaccuracy has been shown to occur where a subject has been imaged in oblique plane(s) rather than true orthogonal planes. The higher the level of positional deviation, the higher the level of measurement variance, such that the measurement of a structure that appears to be head on in one plane may appear infinitely long and cannot be measured accurately. Subsequently loading the axial series of images into one or more of the volumetric or 3-Dimensional imaging packages such as multi-planar reconstructions (MPR's), maximum intensity projections (MIP's) or curved reconstruction will allow another two planes of evaluation whereby a preferred orthogonal plane may be used to present one end of a structure and throughout the length of the structure. This may enable accurate measurements) to be made in an image plane that captures the positional deviation of a structure more reliably.

The function of the measurement correction accessory module is to provide a reference matrix based on typically 10 millimetre cubes that can be used on all imaging platforms, and that will facilitate comparison measurement evaluations) by direct, comparative and interpolated measurements), as a comparison to the measurements) derived only by modality installed reporting and measurement platforms. The modality specific measurement correction phantom for computed tomography (CT) 91 achieves this in a number of ways that are not incorporated into these cross-sectional imaging modalities at present. Firstly, the 10 millimetre squares of the matrix give direct comparison to cross-sectional measurements (2-Dimensional) derived from x-axis to y-axis linear and planar readings, and also for length measurement (2-Dimensional) derived from z-axis linear and planar readings. Measurement values can easily be matched in any direction and at different magnifications against the reference values of the module placed in the table. The reporter may access the said measurement correction phantom matrix by moving the image level reference line into the region of the table in any or the three orthogonal planes. The presence of the higher attenuation spheres of 2 millimetres gives a small centre of reference that will not hinder the placement of electronic callipers and the distance interval to the next centre of the sphere, and the reference distance between both points is 10 millimetres. In the case of measurement differences between both platforms, a third method of verification may be required as an independent source of reference, although it may be said that the reference tool is composed of a 10 millimetre cube matrix that can be multiplied to larger base multiples. It would not be unreasonable to assume that images produced by the scanner in all three planes should be resolvable by the measurement correction accessory tool.

Secondly, where images have been viewed and measured in oblique planes by the reporter, there have been demonstrated measurement inconsistencies that have been of significantly high levels as to be a cause for concern. Without knowing for certain as to whether the anatomy of a structure has altered significantly as in the case of an aneurysmal aorta in a patient, the only way of verifying the correctness of measurement is by examination using multiple imaging methods. In this case, it is more likely that any high ended measurement variance will be picked up at this stage. In the case of the measurement accuracy correction tool, the strength of its design is that the reference matrix can be applied across all three orthogonal imaging planes, as well as a wide range of oblique plane reconstructions. Figure 52 illustrates a computerised tomography (CT) 111 scanner and imaging table 112 with a patient lying 113 on it. A structure is chosen to be measured which in this case is an aorta. Typically a line is drawn with the electronic callipers 114 and this is measured and a value(s) of diameter is obtained using the imaging modality measurement tools (Figure 53). A more precise measurement of the image may be obtained if a line was drawn parallel to the image of the aorta 115 since this would capture with the least distortion both walls of the structure. This would have to be the case at all positions of the aorta throughout the length of travel in the z-axis and maintaining a parallel position despite tortuous twisting of the aortic structure in three planes. Measurements taken in the three other planes as illustrated will result in a range of different valued due to elongation and distortion effects 116, 117, 118. Where measurements are taken with the electronic callipers across an aneurysm 116, the distance is noted and a second duplicate line is drawn manually or by copy and paste software function. The duplicate line may be dropped to the level of the measurement accuracy correction 91 and appropriately windowed in terms of image brightness and contrast, so that the image(s) of the matrix points can be visualised. The duplicated image line is now seen in the proximity of the reference matrix for comparison. The linear measuring tool can then be again used to measure a line from a selected matrix point to another matrix point until a length or length close'to is obtained. Where neighbouring matrix points are not easily visualised due to the image thickness set, this should be increased until other useful images of the sphere(s) are seen. Where the line is achieved as a result of mapping successive linear points in the reference matrix at oblique angles, it will be noticed that lines corresponding to whole numbers of length are achieved from joining odd numbers of 3 points of the imaged spheres and above. The design of the reference matrix has been based on a square cubic concept, but also with geometrical relationships inbuilt such as the 3 centimetre height by 4 centimetre length by 5 centimetres hypotenuse concept that allows an imaginary triangulation to be drawn in the imaging matrix at the oblique angle at where the original measurement tool value was taken. The imaginary triangle will enable readings to be taken in three directions relative to the original reading(s). The lengths of each component of the triangle will give a reference length of 3, 4 and 5 centimetres length that may be applied as comparison to the measurements taken in the respective plane of the aorta and any differences in measurement may be seen as degree(s) of measurement inaccuracy prevalent in that plane of viewing.

Other combinations using the concepts of using equal length between two 1 centimetre intervals of the matrix may produce triangles with similar vertical, longitudinal and transverse length of 2 centimetres by 2 centimetres with a hypotenuse length of the square root of 8 which is equivalent to 2.828 centimetres (to three decimal places), and on a smaller scale 1 centimetre section by 1 centimetre similar length side triangle with a hypotenuse length of 1.414 centimetres. The combinations of said method of applying Pythagorean concepts to the triangles in order to calculate or infer length measurement calculations within or relative to the matrix is by way of example only, and is only an imaginary geometrical concept applied to a situation, and may be extended to other combinations of longitudinal, transverse and oblique plane measurements.

Correspondingly, the length of the duplicated original measurement may be compared with that of the component line of the triangle that best approaches that of the oblique plane of the original reading. These types of comparison readings can be taken in any orthogonal or oblique plane and across the width of the imaging table and provides a reasonably fast and accurate method of verifying linear diameter and length of manufacturer software generated value against the reference matrix. In figure 53, a line drawn parallel to the reading line and passing through the area of interest may be of correct length 115, but may show inaccuracy by magnification due to the distance traversed to the detector 116,117,118 and the fan beam characteristics of the X-ray source. Also, a degree of geometrical distortion may occur due to the increased distance traversed by the X-ray beam in reaching more laterally situated detectors in the detector array of the scanner. Consequently, the registration of the image and measurement of it may give an inaccurate result. Other lines drawn from the anatomical structure vertically down to the reference matrix will likely be inaccurate since they do not truly represent the structure being imaged and represent a variable and detrimental degree of geometrical distortion.

The integral internal and external reference(s) of the modality specific measurement correction phantom 91 may be used as a universal reference for images generated in all planes. Failure of measurement accuracy may be attributed to the inability of the processing algorithm of the software measurement protocol to resolve length or diameter changes that are either close to or at 0 degrees or 180 degrees to its plane of viewing. The consequence of this is that the algorithm does not register changes that are at or close to zero in the viewing plane, but viewed at 90 degrees relative to the original viewing plane, these smaller registered changes may be representative of larger changes as viewed from a perpendicular point or different orthogonal plane, but which would never have been reflected in the final generated image or associated measurement value(s) taken in the original viewing plane.

Another modality specific measurement correction phantom 119 of the universal imaging phantom is for evaluation of the measurement accuracy of magnetic resonance imaging (MRI) and is designed to work in conjunction with the base frame 1 and measurement tube(s) assemblies 10, 11, 12, or in isolation underneath the object or region(s) of interest, as in the case by way of example only, where the measurement accuracy correction phantom may be integrated unobtrusively into the body of the imaging table of the magnetic resonance imaging (MRI) apparatus, and where the construction of the said measurement accuracy correction phantom is made from perspex (RTM), acrylic or other transparent and non-magnetic material frame which may be shaped into any desired shape but by way of example only, an oblong shape as it is more suited to the design of current MRI scanner tables, and where the said measurement accuracy correction phantom comprises a number of not less than two, and typically not more than five planar single sections, in order that the added inertia to the table is minimised, and that table indexing and movement characteristics are not altered, and where each complete sectional layer is typically of such a thickness that a 5 millimetre or otherwise diameter sphere of oil or other magnetic resonance signal generating fluid is embedded into the middle of the two sections and in an indentation on each upper and lower surface at a plurality of appropriately positioned and linearly related loci across the surface of the material to form lines of reference on the said section(s), and where the separation of these oil spheres is typically 15 millimetres longitudinally and transversely from each of their respective centres so as to form a 15 millimetre cubical matrix covering the larger aspect of the upper surface of the section, and where by way of example only, the oil spheres are arranged such that the first and last sphere is 5 millimetres diameter with a spatial separation of 15 millimetres longitudinally and a transverse width separation of 15 millimetres across the whole of the said measurement accuracy correction phantom in that specified layer and all other layers forming the construction. The construction is illustrated in figure 61 where layer 1 is the upper layer of the said measurement accuracy correction phantom 120, layer 2 the next layer beneath 121, layer 3 the next layer beneath 122, layer 4 the next layer beneath 123 and layer 5 the lowermost layer of the construction 124. Figure 61 illustrates a magnified X2 axial or transverse view of the measurement accuracy correction phantom 125, and shows the positioning of the 5 millimetre oil capsules 126 required to form the correction matrix. The 5 millimetre oil capsule is encased between the lower surface of the upper layer and the upper surface of the lower layer and lies inside a hemispherical indentation of each surface such that when the two layers are put together, it is encapsulated inside of a spherical hollow and sealed from environmental degradation. Access to image(s) of the measurement correction phantom is similar to that for the CT measurement accuracy correction phantom and the 15 millimetre matrix may be accessed by dropping the plane of viewing below the subject being measured. It is important however that in order to incorporate the reference matrix of the correction tool into the image, the field of view has to be set to a large enough value at the localisation part of scanning, and it is advisable to use three orthogonal planes in order to indicate the degree of reference matrix inclusion. The process of measurement accuracy correction parallels that as for the CT correction matrix except that the correction matrix is based on 15 millimetre cubes instead of 10. Lines drawn between the centre points of each oil capsule longitudinally, transversely and vertically will give measurement accuracy reference comparison against value(s) derived from imaging modality measurement tools in orthogonal planes, whilst oblique measurements may be calculated by the application of geometrical relationships as applied to the CT measurement accuracy correction phantom. Figure 59 illustrate a sagittal view of an imaginary triangle reference applied to the correction matrix image to calculate length in oblique planes, and figure 60 illustrates a coronal view of the application of lines from one point of reference to another and the measurement of linear distance in longitudinal and transverse planes. Figure 61 illustrates a 60 millimetre line reference

127, a non-inverted 45 millimetre by 60 millimetre by 75 millimetre imaginary triangle reference

128, and a base inverted 45 millimetre by 60 millimetre by 75 millimetre imaginary triangle reference 129.

Claims

CLAIMS Claim 1

A universal imaging phantom for use in quality assurance testing of a broad range of radiological imaging apparatus to perform measurement accuracy verification and correction by use of its modality specific accessory phantom(s) and modality specific measurement corrections phantom(s) to providing image(s) of the selected radiological phantom(s) and by the respective imaging method, and using the internal and external reference markers of diameter(s), area(s), volume(s) and length(s) contained in the design of the phantom to evaluate the capacity of a given imaging machine to reproduce measurement value(s) identical or of the closest match to the reference value(s) of the phantom and where the use of these phantoms when imaged will generate both 3-dimensional image data sets (volume acquisitions), 2-Dimensional radiological planar images, screen capture images, images of other pictorial or graphical format(s), or combinations of said image(s) types of the said phantom in a required position in / on the selected or preferred imaging apparatus, and where the volume image data set, image(s), series of images or screen captures of the radiological phantom functions as an omni-directional. nonlinear, and linear distance, cross-sectional area and volume reference tool, and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, enables the phantom tool(s) to function primarily to evaluate the response of the scanner 3-Dimensional image registration software (volumetric), or other image display and measurement evaluation system, to process / generate from the raw data produced during the image acquisition stage of scanning, image(s) or series of images of the radiological phantom(s), which ideally should be accurately represented in terms of both its 3-Dimensional spatial co-ordinates and planar variation(s) during the incremental or translational (dynamic) imaging processes of computed radiography (CT), or the static imaging processes as in magnetic resonance imaging (MRI), digital subtraction angiography (DSA), radio-fluoroscopy (RF), nuclear (isotope) imaging (NI), computed radiography (CR), or in combinations of said imaging modalities and other specialised imaging modalities, to further validate their recognised capabilities of accurately measuring parametric value(s) of cross-sectional diameter(s), area(s), non-linear and linear length(s), and volume, as compared against the known and stated reference value(s) for the particular phantom configuration, specialised sub-unit(s) or combination of the radiological phantom, and to selectively apply this phantom in measurement situations where the subjects) being imaged or the area(s) of interest are predominantly of a non-linear shape or configuration and where the imaged structure(s) or subject(s) describe or exhibit a continuous, intermittent or combined nonlinear 3-Dimensional variations) in its spatial and vector co-ordinates (along x, y, z and oblique axes) along all or any part of its structure(s), and where the established methods of linear measurement(s) when applied to 2-Dimensional planar measurements), or 3-Dimensional measurements) only involve any combinations) of only two out of the three axis (x, y and z) components) of the imaged and measured structure(s), is seen to produce both erroneous and unpredictable measurement value(s), and also found in circumstances where measurements) of ₍ existing designs of 3-Dimensional linear reading phantom(s) with integrated measurement reference(s) are shown to be limited predominantly to linear or oblique measurements in a range of orientations, but where it is entirely unsuited to measuring objects which are non-linear, convoluted, curvate, concentric, eccentric, curvilinear, circular, spherical, truncated or spiral in its shape, and to which the aforementioned radiological phantom is used to evaluate the capability of the imaging machine to accurately measure non-linear structures may be regarded as a primary tool function, and by way of its design provides an array of other integral linear modality specific accessory phantom(s) and modality specific measurement accuracy correction phantoms, along with each respective phantom principle(s) of operation, method(s) of use and tool function(s), that may be employed in linear measurement accuracy verifications) for each of the imaging modalities and machine apparatus that is to be tested, and which may regarded as a secondary tool function, the components of the universal imaging phantom comprising: a base frame(s) composed of two longitudinal and two transverse sections that are fixed at their end(s) to provide a square, oblong or otherwise shaped construction, and having hole(s) in the longitudinal members for insertion of non-magnetic locking pin(s) for the fixed or releasable securing of a singularity or plurality of phantom support column(s) which support modality specific accessory phantoms for computed tomography (CT), magnetic resonance imaging (MRI), digital subtraction angiography (DSA) and radio-fluoroscopy (RF), and incorporates in the body of the said phantom support column a plurality of octagonal shaped or otherwise shaped sockets for the releasable or fixed attachment of a singularity or plurality of modality specific accessory phantom(s) for computed tomography (CT) called z-axis measurement tube(s), and where clip extensions on the face(s) of said phantom support column(s) releasably attach smaller linear versions of the said z-axis measurement tube called x and y-axis linear measurement tube(s), and where the thinner edge(s) of the said phantom support has rulers marked around its periphery and being marked with metric, Imperial or other preferred unitary scale(s) of measurement; and a modality specific accessory phantom for measurement accuracy verification of diameter, area, volume and distance measurements) of image(s) generated by computerised tomography (CT), magnetic resonance imaging (MRI), digital subtraction imaging (DSA) and radio- fluoroscopy (RF) imaging apparatus by imaging the said modality specific phantom in any one of the indicated imaging modalities or imaging apparatus and using the generated image(s) of the said phantom as a source of reference for diameter(s), area(s), volume(s) and length(s), and consisting of a base frame with a singularity or plurality of phantom support column(s) attached to the longitudinal member(s) of the base frame by the alignment of the holes of the locking extensions) of the phantom support column(s) and the hole(s) in the longitudinal member(s) and the insertion of a retaining pin, such that the phantom support column(s) are able to releasably support on each of its faces and by means of a plurality of clip extensions for attaching x-axis and y-axis linear measurement tube(s) along the horizontal and vertical central lines of the said phantom support column, and where a singularity or plurality of z-axis measurement tube(s) may be orientated and releasably or fixedly attached within the octagonal or otherwise shaped sockets of the said phantom support column, such that on consequent imaging and viewing, the x and y-axis measurement tube(s) create a planar image of the linear scale reference(s) in the axial and sagittal orthogonal planes at a point corresponding to the central area or iso-centre of the imaging matrix, although further imaging may be performed with the universal imaging phantom in each of the peripheral areas of each of the four imaging quadrants of the imaging matrix, and where the image(s) of the x-axis and y-axis linear reference tubes are recorded in a limited number of axial, sagittal and coronal images, and the z-axis measurement tube is recorded in an extensive number of axial, sagittal and coronal images such that the length measurement tools of the scanner can be applied to the images of the x-axis and y-axis linear measurement tools and a planar length measurement may be performed along the length of the wire or the length of the radio-opaque fluid column within the measuring tube, and comparison of the value(s) of diameter of the central wire of the measurement tube, the width of the measurement tube, the length of the central wire or the fluid column may be compared against the reference value(s) contained internally and externally in the design of the said linear measurement tube(s), and where the user is able to further calculate area of the said measurement tube(s) by halving the measured diameter to get the radius of the measurement tube and the cross-sectional area will be the product of πr² where π is a constant and r² is the square of the radius, and volume may be further calculated by multiplication of the length of the measurement tube, such that measurement value(s) derived may give an indication of measurement accuracy, presence of image distortion in the imaging field, and the locality and extent of any measurement inaccuracies, while the z-axis measurement tube(s) will typically not be suited to measurement in a planar section since curvatures will generally traverse in and out of a given orthogonal plane such that ordinary 2-Dimensional or planar measurement tools would not be able to provide an accurate measurement of length for a non-linear structure; and a modality specific accessory phantom for measurement accuracy verification of diameter, area, volume and distance measurements) of image(s) generated by computerised tomography (CT) and consisting of a base frame with phantom support column(s) securing by engagement of the said phantom support column locking extensions) with the hole(s) of the longitudinal members of the base frame and releasably or fixedly held by a locking pin, and where additionally an accessory phantom base plate is locked into the said base frame and secured with said locking pins, so that a modality specific accessory phantom for computed tomography (CT) may be slotted into the locator groove of the accessory phantom base plate, such that the x-axis and y-axis linear measurement tube(s) may be attached to the clip extensions of the phantom support column, and additional z-axis measurement tube(s) may be mounted and secured into the octagonal sockets of the phantom support column(s), such that on generation of image(s) of said configuration of universal imaging phantom, the x-axis and y-axis linear measurement tube(s) create a linear scale(s) measurement reference at the iso- centre of the field of view or at the periphery if preferred, along with image(s) of the z-axis measurement tube(s) which will enable the image measurement tools of the scanner to be used to measure the diameter(s) of the central wire of the x-axis or y-axis linear measurement tubes in two orthogonal imaging planes or the diameter of the measuring tube, and be able to further calculate area of the said measurement by halving the measured diameter to get the radius of the measurement tube and where the cross-sectional area will be the product of πr² where π is a constant and r² is the square of the radius, and volume may be further calculated by multiplication of the length of the measurement tube, and where the value(s) derived by calculation are compared to the reference value(s) of the measurement tube(s) thus giving an indication of accuracy of linear measurement across the imaging field in two orthogonal imaging planes, but where limitation(s) of z-axis measurement tube(s) evaluation may occur due to the in and out of viewing plane characteristic of the said measuring tube(s) which may comprise a measuring tube of assymetrical shape which cannot be represented by any one particular orthogonal or planar viewing plane as the image is a non-planar structure having variable spatial and positional image co-ordinates in all three orthogonal x, y and z-axis, such that these non-linear structures are best viewed on a 3-Dimensional or volumetric viewing display, as compared to structures whose spatial and linear co-ordinates only vary in two out of the three orthogonal planes, such that these linear structures are adequately viewed on 2-Dimensional viewing displays, and where correspondingly, measurements) of diameter, area, volume and length are likely to become erroneous as a result, and additionally where the image(s) of the second modality specific accessory phantom for computed tomography (CT) may be used to evaluate longitudinal distance(s), transverse distance(s), and the capability of the computed tomography imaging apparatus to provide spatially accurate reconstructed images in all three orthogonal planes (translational linearity) and to produce image(s) during other image reconstruction methods found in 3-Dimensional image block viewing platforms which include multi-planar reconstructions (MPR' s), maximum intensity projections (MIP's) and curved reconstructions, that maintain the parallel lines of reference that were present in the original image dataset (parallelism), and where the modality specific accessory phantom itself has the distinguishing features in its design of oppositely mounted sections in which one limb is twice the width of the other and where the configuration of said limbs on one side is opposite in position on the other side, and where each limb has a cylindrical radio-lucent measurement rod with radio-opaque scalar markings indicating typically 5 millimetres and 10 millimetres along its length that produce the reference value(s) of diameter and length in the image(s) or volumetric image dataset, and where the spatial relationship^) of said accessory phantom produces typical reference(s) of length and separation of the lines in a given orthogonal viewing plane which may be used to evaluate longitudinal, transverse and depth length measurements), and assess transcriptional linearity and parallelism in an image(s); and a modality specific accessory phantom for measurement accuracy verification of diameter(s), area(s), volume(s) and distance(s) measurements of image(s) generated by computerised tomography (CT) and consisting of base frame, accessory phantom base plate, and modality specific accessory phantom for computerised tomography (CT) and where the accessory phantom base plate may be mounted into the said base frame and releasably or fixedly secured by locking pins, such that the modality specific accessory phantom for computed tomography (CT) may be releasably or fixedly secured to the base plate using the locator groove and the complementary engagement mechanism of the said accessory phantom, such that the images of the said accessory phantom may be used to evaluate longitudinal distance, transverse distance, the capability of the imaging apparatus to provide spatially accurate reconstructed images in all three orthogonal planes (translational linearity) and to produce images during other image reconstruction methods that maintain the parallel lines of reference generated by the said accessory phantom (parallelism), and where the modality specific phantom itself has distinguishing features of oppositely mounted sections in which one limb is twice the width of the other and where the configuration of said limbs on one side is opposite in position on the other side, and where each limb has a cylindrical radio-lucent measurement rod with radio- opaque scalar markings indicating typically 5 millimetres and 10 millimetres along its length and these produce the reference value(s) of diameter and length in the image(s) or volumetric image dataset where the spatial relationship^) of the said accessory phantom produces typical reference(s) of length and separation of the lines in a given orthogonal viewing plane which may be used to evaluate longitudinal, transverse and depth length measurement(s), and assess transcriptional linearity and parallelism in an image(s); and a modality specific accessory phantom for comparing measurement accuracy verification of diameter(s), area(s), volume(s) and distance(s) measurements of image(s) generated by magnetic resonance imaging (MRI) imaging apparatus and consisting of base frame, phantom support column(s), locking extensions and pins of the phantom support column(s), clip extensions, x and y-axis linear measurement tube(s) and z-axis measurement tube(s), the use of the x and y-axis linear measurement tube(s) to create a linear scale reference at the iso- centre or the periphery of the field of view of the image acquisition to indicate error(s) in planar linear measurement or measurement of images in a planar orientation and having variable spatial co-ordinates in only two out of the three orthogonal axes, use of z-axis measurement tube(s) in a variety of shapes to create an image of the said z-axis measurement phantom which is non-planar and having variable spatial co-ordinates in all three orthogonal axes x, y and z, and where the measurement tubes may be used in a singularity or plurality and mounted into the octagonal recesses of the phantom support column(s), such that on subsequent imaging and viewing, the x and y-axis measurement tube(s) create a planar image of the linear scale reference(s) in the axial and sagittal orthogonal planes at a point corresponding to the central area or iso-centre of the imaging matrix, although further imaging may be performed with the universal imaging phantom in each of the peripheral areas of each of the four imaging quadrants of the imaging matrix, and where the image(s) of the x-axis and y-axis linear reference tubes are recorded in a limited number of axial, sagittal and coronal images, and the z-axis measurement tube is recorded in an extensive number of axial, sagittal and coronal images such that the length measurement tools of the scanner can be applied to the images of the x-axis and y-axis linear measurement tools and a planar length measurement may be performed along the length of the wire or the length of the radio-opaque fluid column within the measuring tube, and comparison of the value(s) of diameter of the central wire of the measurement tube, the width of the measurement tube, the length of the central wire or the fluid column may be compared against the reference value(s) contained internally and externally in the design of the said linear measurement tube(s), and where the user is able to further calculate area of the said measurement tube(s) by halving the measured diameter to get the radius of the measurement tube and the cross-sectional area will be the product of πr² where π is a constant and r² is the square of the radius, and volume may be further calculated by multiplication of the length of the measurement tube, such that measurement value(s) derived may give an indication of measurement accuracy, presence of image distortion in the imaging field, and the locality and extent of any measurement inaccuracies, while the z-axis measurement tube(s) will typically not be suited to measurement in a planar section since curvatures will generally traverse in and out of a given orthogonal plane such that ordinary 2-Dimensional or planar measurement tools would not be able to provide an accurate measurement of length for a non-linear structure; and a modality specific accessory phantom for comparing measurement accuracy verification of diameter(s), area(s), volume(s) and distance(s) measurements of image(s) generated by magnetic resonance imaging (MRI) imaging apparatus and consisting of base frame, phantom support column(s), locking extensions and pins of the phantom support column(s), clip extensions, x and y-axis linear measurement tube(s) and z-axis measurement tube(s), magnetic resonance tank enclosure, longitudinal and transverse water bubble level indicators, adjuster feet mechanism of the said tank enclosure, and where the generated image(s) or volume of image dataset has increased resolution, clarity and interface definition as a consequence of being immersed in water or other preferred fluid, and where said tank enclosure has features of a plastic or other suitable transparent and non-magnetic material tank body with a closed end and shaped to accommodate various configurations of the said base frame, phantom support column(s), locking pins, and x and y-axis linear measurement tube(s), and z-axis measurement tube(s), located and centred within the body of the tank enclosure by locator ridges, and where said accessory phantom is encased into the tank enclosure by a cover plate and screwed into place firmly using fasteners, such that the tank may be filled with water or other preferred fluid through a screw cap in the cover plate, and once filled may be placed within the imaging field of the scanner and levelled using a combination of the adjustment of the adjuster feet and the integral water bubble level indicators of the tank enclosure, and where image(s) or volume image dataset produced may be used to evaluate measurement accuracy relative to the reference value(s) contained within the design of said measurement tube(s) and . where the x and y-axis linear measurement tube(s) create a linear scale reference at the iso- centre or the periphery of the field of view of the image acquisition to indicate error(s) in planar linear measurement or measurement of images in a planar orientation and having variable spatial co-ordinates in only two out of the three orthogonal axes, use of z-axis measurement tube(s) in a variety of shapes to create an image of the said z-axis measurement phantom which is non-planar and having variable spatial co-ordinates in all three orthogonal axes x, y and z, and where the measurement tubes may be used in a singularity or plurality and mounted into the octagonal recesses of the phantom support column(s) and where on subsequent imaging and viewing, the x and y-axis measurement tube(s) create a planar image of the linear scale reference(s) in the axial and sagittal orthogonal planes at a point corresponding to the central area or iso-centre of the imaging matrix, although further imaging may be performed with the universal imaging phantom in each of the peripheral areas of each of the four imaging quadrants of the imaging matrix, and where the image(s) of the x-axis and y-axis linear reference tubes are recorded in a limited number of axial, sagittal and coronal images, and the z-axis measurement tube is recorded in an extensive number of axial, sagittal and coronal images such that the length measurement tools of the scanner can be applied to the images of the x-axis and y-axis linear measurement tools and a planar length measurement may be performed along the length of the wire or the length of the radio-opaque fluid column within the measuring tube, and comparison of the value(s) of diameter of the central wire of the measurement tube, the width of the measurement tube, the length of the central wire or the fluid column may be compared against the reference value(s) contained internally and externally in the design of the said linear measurement tube(s), and where the user is able to further calculate area of the said measurement tube(s) by halving the measured diameter to get the radius of the measurement tube and the cross-sectional area will be the product of πr² where π is a constant and r² is the square of the radius, and volume may be further calculated by multiplication of the length of the measurement tube, such that measurement value(s) derived may give an indication of measurement accuracy, presence of image distortion in the imaging field, and the locality and extent of any measurement inaccuracies, while the z-axis measurement tube(s) will typically not be suited to measurement in a planar section since curvatures will generally traverse in and out of a given orthogonal plane such that ordinary 2-Dimensional or planar measurement tools would not be able to provide an accurate measurement of length for a non-linear structure; and a modality specific accessory phantom for measurement accuracy verification of diameter(s), area(s), volume(s) and distance(s) measurements of image(s) generated by digital subtraction angiography (DSA) and radio-fluoroscopy (RF) imaging apparatus and consisting of a base frame with a singularity or plurality of phantom support column(s) attached to the longitudinal member(s) of the base frame by the alignment of the holes of the locking extension(s) of the phantom support column(s) and the hole(s) in the longitudinal member(s) and the insertion of a retaining pin, such that the phantom support column(s) are able to releasably support on each of its faces and by means of a plurality of clip extensions for attaching x-axis and y-axis linear measurement tube(s) along the horizontal and vertical central lines of the said phantom support column, and where a singularity or plurality of z-axis measurement tube(s) may be orientated and releasably or fixedly attached within the octagonal or otherwise shaped sockets of the said phantom support column, such that on consequent imaging and viewing, the x and y-axis measurement tube(s) create a planar image of the linear scale reference(s) in the axial and sagittal orthogonal planes at a point corresponding to the central area or iso-centre of the imaging matrix, although further imaging may be performed with the universal imaging phantom in each of the peripheral areas of the input plate of the image intensifier and in a number of preferred imaging planes so that the image(s) of the x-axis and y-axis linear reference tubes are recorded in various loci across the 2-Dimensional or planar image display of the imaging machine, and the z-axis measurement tube(s) is / are observed in the image(s) in a varying range of orientations and degrees of elongation, foreshortening or distortion, such that the length measurement tools of the imaging machine can be applied to the images of the x-axis and y-axis linear measurement tools and a planar length measurement may be performed along the length of the wire or the length of the radio-opaque fluid column within the preferred measuring tube and comparisons may be made between the measured value(s) of diameter of the central wire of the measurement tube, the width of the measurement tube, the length of the central wire or the fluid column may be compared against the reference value(s) contained internally and externally in the design of the said linear measurement tube(s), and further requiring the user to apply a magnification factor to all measurement(s) performed on all image(s) in that plane, such that calculation of the area of the said measurement tube(s) may be made by halving the measured diameter to get the radius of the measurement tube and the cross-sectional area will be the product of πr² where π is a constant and r² is the square of the radius, and volume may be further calculated by multiplication of the length of the measurement tube, such that measurement value(s) derived may give an indication of measurement accuracy, presence of image distortion in the imaging field, and the locality and extent of any measurement inaccuracies, while the z-axis measurement tube(s) will typically not be suited to this type of measurement in a planar image since its curvatures will generally traverse in and out of a given orthogonal plane such that planar measurement tools found on 2-Dimensional image displays would not be able to provide an accurate measurement of length for a non-linear structure and where compromise would be best achieved by using multiple image(s) and by averaging out the value(s) of the measured section of the said accessory phantom to obtain a best value that may be realistically compared against the reference value(s) contained internally and externally in the design of the universal imaging phantom; and a modality specific accessory phantom for measurement accuracy verification of diameter(s), " area(s), volume(s) and distance(s) measurements of image(s) generated by nuclear (isotope) imaging (NI) and consisting of a base frame with an accessory phantom base plate inserted into it so that the engagement of the said accessory phantom base plate with the hole(s) of the longitudinal members of the base frame enable it to be releasably or fixedly held by a locking pin, so that a modality specific accessory phantom for nuclear (isotope) imaging (NI) may be slotted into the locator groove of the accessory phantom base plate along with other modality specific side mounted accessory phantom(s) which engage to the locater groves(s) of the body of the said modality specific accessory phantom for nuclear (isotope) imaging to form a 2, 3 or 4 lined array of radiation sources which may be used for imaging purposes, and where the modality specific accessory phantom for nuclear (isotope) imaging has typical physical dimensions of 360 millimetres length, 20 millimetres thickness, and 157 millimetres height, with the said accessory phantom having positioned horizontally and at its midpoint two locator grooves similar to those for engaging modules on the accessory phantom base plate and similarly where the locator grooves serve to hold and position more than one side mounted nuclear (isotope) imaging accessory tool module for more elaborate testing with Single Photon Emission Computerised Tomography (SPECT) and Positron Emission Tomography (PET) scanner units, and also where at two points 20 millimetres from the apex of the vertical section, and 20 millimetres from the base of the supporting plate, and in line with the central bisector of the said modality specific accessory phantom, are round cavities extending from one surface and into the material of the said phantom, and positioned parallel and distally to a point of emergence at the other end of the phantom where into this cavity is accurately placed and fed a 14 millimetre square insert, by way of example only, or other preferred shape, that is made of a high attenuation material such as lead or steel, or other suitable material, until it emerges at the remote end of the channelled out square cavity of the tool block for the full 360 millimetre length of the tool, and with the insert itself having a round channel of typically 10 millimetres diameter at its geometric centre, and extending throughout the length of the insert where along the three points of the circular aperture and spaced regularly at typically 40 millimetre intervals, or other preferred length, are pin-hole apertures of typically 0.5 millimetres diameter or other preferred diameter(s), along the length of the measurement tool, and placed securely into this lead insert is a cylinder made from steel and of typically 9 millimetres outside diameter and 7 millimetres inside diameter and 350 millimetres in length, with larger 1 millimetre holes drilled, such that along the length of the insert and corresponding to the pin-hole apertures of the lead insert at 0 degrees, 90 degrees, and 270 degrees are small diameter apertures to allow the radiation to exit, and due to the design is made to carry and seal a plastic isotope tube containing the radioactive substance, typically a metastable salt of Technetium (Tc99m), but other isotopes may be used according to preference, and ensuring that the diameter of the pinpoint apertures is small enough to allow a certain dose rate of gamma radiation photons to pass through so that a suitable pinpointed area may be produced on the scintillation crystal of the gamma camera, and where the markers on the external faces of the measurement scales typically run from negative multiples of 40 millimetres at one end, for example -160 millimetres, -120 millimetres, -80 millimetres, -40 millimetres to zero at the centre of the tool, then to a positive multiple of 40 millimetres at the other end, for example 40 millimetres, 80 millimetres, 120 millimetres and 160 millimetres, and at each of the 40 millimetre points is an aperture for the gamma radiation to be emitted simultaneously from the same locus, but from three different directions, and such that the one end has a lead block locator pin that fits into the lead section of the imaging tool to allow the inserts to be located accurately into position(s) to ensure that the pinpoint radiation emitted is of limited and reduced intensity so as to be registered on the scintillation crystal as a small "hot spot" of recorded high radiation activity, and where also at each end of the cylindrical insert is a screw thread to allow the fitment of two 6.5 millimetre diameter headed steel screw plugs to cap off each end of the cylinder once the loaded insert is placed within it, and where a further disposable 5.0 millimetres transparent plastic insert of 340 millimetres length is used to hold the isotope during testing, using a plastic tube of typically 3 millimetres internal diameter carrying by way of example only, an activity of 30 MBq (MegaBecquerels) and where using this level of activity as a balance provides enough radioactivity to register a "hot spot" of radiation activity on the scintillation crystal so that the acquisition time to register typically 200 Kilocounts is in the time frame of five minutes, rather than having a higher activity of radioactive source (150 MBQ) in the tool that emanates much higher doses of gamma radiation that may be advantageous for shorter acquisition times, but of limited use because the intensity of the radiation beams from the apertures produce hot spots of large diameter such that they overlap with the hot spot of the neighbouring apertures, and at a 40 millimetre distance of separation is likely to create difficulties in defining the centre of the hotspot on the acquired image(s), thus likely causing invalidation of the accuracy of any measurements derived from use of the accessory module, or at least limiting any inferences or validations of measurement(s) based on the image(s) produced, and such that the sealed radiation sources allow measurement accuracy verification to be performed in orthogonal and oblique imaging planes with the configured universal imaging phantom as close to the scintillation crystal as possible or at a measured distance so the magnification effects may be accounted for, such that the generated image(s) allow evaluation of the ability of the scintillation and imaging apparatus to collect gamma radiation, register as a correctly positioned and spatially accurate ("hot-spot) of small diameter and to present a plurality of these radio-active sources as equidistant and clearly defined centre to centre spatial separation from its neighbouring hot- spot in all of the orthogonal imaging planes; and a combination of modality specific accessory phantoms for measurement accuracy verification of area(s), volume(s) and distance(s) measurements of image(s) generated by combination scanners which by way of example only, may utilise both computed tomography (CT) and nuclear (isotope) imaging (NI) machines and where configured universal imaging phantom comprises a base frame, a singularity or plurality of phantom support column(s), an accessory phantom base plate, locking pins of the base plate and phantom support columns, a modality specific accessory phantom for nuclear (isotope) imaging (NI) and a singularity or plurality of modality specific side mounted accessory phantom(s) for nuclear (isotope) imaging (NI) and where the phantom support column(s) are secured to the longitudinal members of the base frame and the locking extensions of the phantom support column by insertion of locking pins, and also where the modality specific accessory phantom for nuclear (isotope) imaging is inserted into the locator groove of the accessory phantom base plate, and other preferred modality specific side mounted accessory phantom(s) for nuclear (isotope) imaging are , similarly located into the locator grooves of the modality specific accessory phantom for nuclear (isotope) imaging and then inserted into the base frame and releasably or fixedly 620

42 image information, compressing the data, transmitting the data, and reconstructing the data and presentⁱng it on an image display, and where the modality specific accessory unit for computed radiography (CR) consists of an imaging section constructed from perspex (RTM) acrylⁱc or other suitably non-magnetic, radiolucent, durable and transparent material and arranged by example only, as an oblong block of typical dimensions 360 millimetres length by 198 mⁱllⁱmetres width and 20 millimetres thickness, where on the underside of the block is an arrangement of radio-opaque markings that when viewed from above describe a number of functⁱonal markings, lines and edge indicators, the lines forming a square on the bottom aspect of the base of typⁱcally 350 mUhmetresJsngthJQL 190 millimetres widtlvwher_€^4iagenal4_tn^ is drawn from each corner to form four triangular sections, another two lines are drawn from the mⁱdpoⁱnt of each edge to the centre of the base dividing each of the triangular sections into two, this ⁱn ⁱtself forms smaller triangular areas across the base area , where along each of these bisecting lines and extending to the edges of the plate are linear scales measured in metrⁱc or Imperial sub-divisions of a metre or a foot respectively, so that typically in the case of a metric scaled base, these subdivisions would be in millimetres and centimetres and extending from the centre point at zero radially to their respective maximum values, and in the case of an Imperial scaled base, these sub-divisions would be in inches or less, and where at each of the four corners of base and at a point typically 90 millimetres above and below the longitudinal (or horizontal) centre line, and 175 millimetres to the left and right of the transverse (or vertical ) centre line are four corner identifiers, each set comprising right angled lⁱnes of typically 30 millimetres length serving to delineate the corners of the base for an X-ray field collimation area test (or area of defined X-radiation exposure), and where on the base there is defined a circle 75 at the geometrical centre of the accessory module for the vertⁱcal central ray of the X-ray tube to be centred prior to radiographic exposure, and which serves as a poⁱnt of centring for the applied X-radiation beam to the said accessory phantom for measurement of computed radiography (CR) images thus ensuring minimal distortion and parallax ⁱn the ιmage(s) generated, and where in every other triangular section of the module, and ⁱnlaid into the polymer substance are functional test units for assessment of image distortion in the form of a geometrical shape module containing circular, square and triangular reference shaped components to evaluate distortion in an image, measurement of resolution and Modulatⁱon Transfer Function (MTF) in the form of a line pairs per centimetre module, sensⁱtometric type testing of the image plate recording system by use of an incorporated wedge filter, and symmetrical square references for further image distortion evaluation and image contrast references, where each of the densities of the squares from number 1 to 8 has a respectⁱve thⁱckness and calibrated effect of reducing radiographic densities across the area of the imaging plate, such that if the contrast level(s) were measured from 1 to 8, the measurements when obtained and plotted on a graph would give a linear relationship of contrast index against the square reference number, and where such testing may be carried out usⁱng an added filter equivalent to 1 millimetre of copper to harden the X-radiation beam and absorb lower energy wavelength radiation that may reduce the image contrast levels in the ιmage(s) generated, using a prescribed or standardised test exposure at a specified (focus to ⁱmage plate distance) to reduce the effects of variations) in image quality as a result of differences in X-radiation beam characteristics, and further where the imaging plate(s) used for recordⁱng the latent or stored image(s) are solely used for quality assurance (QA) testing and read or ⁱnterrogated using a specified computed radiography imaging plate reader of known performance, and where the measured value(s) derived from the image(s) may be compared against the reference value(s) for the particular said accessory phantom thus ⁱndⁱcatⁱng the level(s) of variance or compliance of a range of factors that might reduce the resolutⁱon, content and geometry of an image, and indicative of errors in the imaging chain or as a consequence of image transmission across networks; and secured into position using locking pins, and correspondingly where x-axis and y-axis measurement tubes are attached to the face(s) of the phantom support column(s) and a singularity or plurality of z-axis measurement tubes engaged and fastened into the octagonal socket(s) of the said support column, such that when placed into each imaging machine in turn and imaged, generates image(s) and a volumetric image dataset of the said universal imaging phantom incorporating modality specific accessory phantoms for computerised tomography (CT) and nuclear (isotope) imaging, such that on imaging the x-axis and y-axis linear measurement tube(s) create a linear scale(s) measurement reference at the iso-centre of the field of view or at the periphery if preferred, along with image(s) of the z-axis measurement tube(s) which will enable the image measurement tools of the scanner to be used to measure the diameter(s) of the central wire of the x-axis or y-axis linear measurement tubes in two orthogonal imaging planes or the diameter of the measuring tube, and to be further able to calculate area of the said measurement by halving the measured diameter to get the radius of the measurement tube and where the cross-sectional area will be the product of πr² where π is a constant and r² is the square of the radius, and volume may be further calculated by multiplication of the length of the measurement tube, and where the value(s) derived by calculation are compared to the reference value(s) of the measurement tube(s) thus giving an indication of accuracy of linear measurement across the imaging field in two orthogonal imaging planes, but where limitations) of z-axis measurement tube(s) evaluation may occur due to the in and out of viewing plane characteristic of the said measuring tube(s) which may comprise a measuring tube of assymetrical shape which cannot be represented by any one particular orthogonal or planar viewing plane as the image is a non-planar structure having variable spatial and positional image co-ordinates in all three orthogonal x, y and z-axis, such that these non-linear structures are best viewed on a 3-Dimensional or volumetric viewing display, as compared to structures whose spatial and linear co-ordinates only vary in two out of the three orthogonal planes, such that these linear structures are adequately viewed on 2-Dimensional viewing displays, and where correspondingly, measurement(s) of diameter, area, volume and length are likely to become erroneous as a result, and where further evaluation of the image(s) generated by the nuclear (isotope) imaging machine evaluates the ability of the scintillation and imaging apparatus to collect gamma radiation, register as a correctly positioned and spatially accurate "hot-spot" or small diameter dot of typically 2 millimetres diameter and to present a plurality of these hot-spots as accurately positioned and equidistant with clearly defined centre to centre spatial separation of typically 40 millimetres from its neighbouring hot-spot in the same line and with all lines of hot-spots being separated by 100 millimetres in all of the orthogonal imaging planes; and a modality specific accessory phantom for measurement accuracy verification of diameters), area(s), volume(s) and distance(s) measurements of image(s) generated by computed and digital radiography apparatus (CR), and transferred by network technologies to picture archive and communications systems (PACS) and teleradiology systems using digital imaging and communications in medicine (DICOM) or other accepted image transfer standard which comprises a modality specific accessory phantom for computed radiography (CR) which may be fitted into the base frame to engage with the locating holes of the longitudinal members of the base frame and releasably or fixedly secured with retaining pins and where additional phantom support column(s) may be attached and secured by engaging their locking extensions with a hole in the said longitudinal member of the base frame and securing with said locking pin(s), such that by way of example only, short and long linear measurement tubes may be included for linear measurement testing of image(s) produced by the CR image production process and forming the basis for a standard or reference image, setup of imaging apparatus, method of imaging and evaluation and measurement of generated image(s), and the evaluation of any alterations in the image(s) that may be incurred as a consequence of digitising the a modality specific phantom for measurement accuracy verification of diameters), area(s), volume(s) and distance(s) measurements of image(s) generated by computed and digital radiography apparatus (CR), and transferred by network technologies to picture archive and communications systems (PACS) and teleradiology systems using digital imaging and communications in medicine (DICOM) or other accepted image transfer standard, and which comprises of a modality specific accessory phantom (tubular) for computed radiography (CR) consisting of an oblong frame used for the supporting of measurement tube(s) used in the accessory phantom that may be inserted into the base frame and secured with locking pins, and whose dimensions are typically 408 millimetres long by 198 millimetres width, and 20 millimetres thickness, and where the frame is typically divided unequally into three sections, the first section having by way of example only, its point of origin 123 millimetres from the vertical edge of the left sided column and bounded by a vertical column extending from one longitudinal edge to another, forming a section on the left side of the construction called the main vertical window of the accessory module where situated at the midpoint of the vertical column is a horizontal column typically 20 millimetres square, which extends to join with the transverse column of the right side of the frame construction, the horizontal column dividing the remaining space into two equal portions, a lower section called the lower horizontal window of the accessory module, and an upper section called the upper horizontal window of the accessory module, and where the horizontal column would originate from a point 79 millimetres from the base of the section, the main vertical window would be 160 millimetres transversely and 113 millimetres longitudinally, and the two divided smaller sections would be 69 millimetres transversely by 235 millimetres longitudinally, and where at various positions on the lateral surface of the longitudinal edges of the frame, and spaced 40 millimetres apart, are 30 millimetre deep holes perpendicularly into the material of the base plate which corresponds to the spacing of holes on the lateral aspects of the longitudinal members of the base frame, where a locking pin may secured into each of the two holes to allow the base plate accessory module to be fixedly or releasably and / or variably secured together with the base frame, and where said frame has a number of retaining clips for holding specified diameter linear measuring tube(s) in longitudinal, transverse or oblique planes, and by way of example only, the typical diameter(s) for the transverse measurement tube(s) would be 20 millimetres and the tube length 140 millimetres for the left hand vertical tubes, and where this section would typically incorporate three of the oblique measurement tubes of differing cross- sectional diameter(s) and length(s) of imaging column, and in the upper right hand section of the frame that carries the longitudinal measuring tubes, the tube diameter(s) would typically be 25, 20, 15 and 10 millimetres cross-section and of tube length 215 millimetres, and would incorporate four measurement tubes of differing cross-sectional diameter(s) and length(s) of imaging column, the lower right hand section carrying the obliquely mounted measuring tubes, and would typically require similar diameter measurement tubes of 20, 10 and 5 millimetres cross-sectional diameter(s) and of typical length variations between 235 -160 millimetres length, but with different lengths of imaging column, and by which the mounting or securing of these said measurement tube(s) in their defined and relative positions, is by the provision of wedges shaped into the construction at certain positions in the construction that hold the supporting clips, and whereby the final construction once assembled can be mounted into the base frame and secured into position with the retaining pins located into the recesses on the said accessory phantom, where each of the measuring tubes will have an imaging volume of fluid contained in the body, and the column length of each tube can be varied according to the preferred choices, such that typically, in the left hand section a 140, 100 and 60 millimetres length selections are used, and in the top right hand section, typically 215, 175, 135 and 100 millimetres length selection is used, and in the lower right hand section, typically 235, 175, and 100 millimetres length selection is used; and a modality specific measurement accuracy correction phantom for computed tomography (CT) is used to generate a 1 centimetre cubical reference matrix as a component in an image and below the subject or phantom being imaged such, that the image of the said matrix is integrated with image(s) of the universal imaging phantom configured for computed tomography (CT) and containing the preferred modality specific accessory phantom(s) that may be accessed if required by dropping the viewing plane to a point below that of the said modality specific accessory phantom for computed tomography (CT), such that the said measurement accuracy correction phantom is designed to work in conjunction with the base frame and secured phantom support column(s), x-axis and y-axis linear measurement tube(s) attached to the faces of the said phantom support column(s) by clip extensions and z-axis measurement tube(s) mounted and secured into the octagonal or otherwise shaped sockets of the phantom support column, and where by way of example only, the measurement accuracy correction phantom is integrated into the imaging table of the computed tomography (CT) apparatus, and the construction of the said measurement accuracy correction phantom is made from perspex (RTM), acrylic or other radiolucent and non-magnetic material frame and shaped by way of example only into an oblong shape, and where the said measurement accuracy correction phantom comprises a number of not less than two, and typically not more than five planar single sections, in order that the added inertia to the table is minimised, and that table indexing and movement characteristics are not altered, and where each complete sectional layer is typically of such a thickness that a 2 millimetre, 5 millimetre, 10 millimetre or otherwise diameter hyper- dense sphere of low to moderate x-ray attenuation can be embedded into the middle of the section at a plurality of appropriately positioned and linearly related loci across the surface of the material to form lines of reference on the said section(s), and where the separation of these hyper dense spheres is typically 10 millimetres transversely and longitudinally from each of their respective centres so forming a 10 millimetre square matrix covering the larger aspect of the upper surface of the section, and where by way of example only, the spheres are arranged such that the first and last sphere is 2 millimetres diameter along the longitudinal length and the transverse width of the whole of the said measurement accuracy correction phantom in that specified layer and all other layers except the middle layer which is different in that it is composed of two separate longitudinal lines at the most lateral or outer points of the construction and the reference matrix, with each said line having embedded in them 10 millimetre diameter hyperdense spheres of low to moderate x-ray attenuation which are offset by 10 millimetres distance and generally separated by 20 millimetres distance, with the rest of the longitudinal lines at all other levels being composed of 2 millimetre diameter spheres and with 10 millimetres separation to give general continuity throughout the correction matrix, and where the function of the 10 millimetre hyperdense spheres are for reference purposes and are present only to delineate the most lateral or outer edge of the correction matrix, and the use of an additional number(s) of similarly sized and shaped sections placed squarely, closely and fixedly to the said section(s) will provide an overall thicker sectional construction and correction matrix, and where on one or both ends of the sectional construction is a section containing a range of disks of increasing diameter and depth whose function is to give length reference to the electronic cursor measurements of known diameter planar disks of 25, 20, 15, 10, 2 millimetres diameter, and functions to provide a selection of reference diameters) to test the image measurement tools for their abilities to measure diameter(s) and depths in different orthogonal planes, and such that the image of the correction matrix is based on a 1 centimetre cube and at its most basic the distance relationship between the centres of a single sphere to the centre of the next should be 1 centimetre in longitudinal, transverse and vertical directions, and if the point of reference was to be taken from the centre of one sphere to the centre of another obliquely, then the distance would be the square root of 2 which is 1.414 centimetres, noting strictly that there are no direct references to actual triangles within the structure since the correction metric can only function from 1 centimetre cubes or from multiples thereof in any direction and any reference made to geometrical relationships are purely in the interests of quick calculation of length, and by way of example only, a 3 centimetre line of reference drawn across four spheres and a 4 centimetre line drawn across five spheres will have a line that joins them that passes through six of the spheres obliquely and will have a length of five centimetres; and a modality specific measurement accuracy correction phantom for magnetic resonance imaging (MRI) is used to generate a 15 millimetre cubical reference matrix as a component in an image and below the subject or phantom being imaged, such that the image of the said matrix is integrated with image(s) of the universal imaging phantom configured for magnetic resonance imaging (MRI) and containing the preferred modality specific accessory phantom(s) that may be accessed if required by dropping the viewing plane to a point below that of the said modality specific accessory phantom for magnetic resonance imaging (MRI), such that the said measurement accuracy correction phantom is designed to work in conjunction with the base frame and secured phantom support column(s), x-axis and y-axis linear measurement tube(s) attached to the faces of the said phantom support column(s) by clip extensions and z- axis measurement tube(s) mounted and secured into the octagonal or otherwise shaped sockets of the phantom support column, and water or other fluid tank enclosure if preferred, and by way of example only, the measurement accuracy correction phantom is integrated into the imaging table of the magnetic resonance imaging (MRI) apparatus, and where the construction of the said measurement accuracy correction phantom is made from perspex (RTM), acrylic or other radiolucent and non-magnetic material frame and shaped by way of example only into an oblong shape, and where the said measurement accuracy correction phantom comprises a number of not less than two, and typically not more than five planar single sections, in order that the added inertia to the table is minimised, and that table indexing and movement are not altered, and each complete sectional layer is typically of a thickness that a 5 millimetre or otherwise diameter sphere of oil or other magnetic resonance signal generating fluid is embedded into the middle of the two sections and in an indentation on each upper and lower surface at a plurality of appropriately positioned and linearly related loci across the surface of the material to form lines of reference on the said section(s), and where the separation of these oil spheres is typically 15 millimetres longitudinally and transversely from each of their respective centres so as to form a 15 millimetre cubical matrix covering the larger aspect of the upper surface of the section, and where by way of example only, the oil spheres are arranged such that the first and last sphere is 5 millimetres diameter with a spatial separation of 15 millimetres longitudinally and a transverse width separation of 15 millimetres across the whole of the said measurement accuracy correction phantom in that specified layer and all other layers forming the construction forming the correction matrix, and such that following imaging, access to image(s) of the measurement correction phantom is similar to that for the CT measurement accuracy correction phantom and the 15 millimetre matrix may be accessed by dropping the plane of viewing below the subject being measured, where lines drawn between the centre points of each oil capsule longitudinally, transversely and vertically will give measurement accuracy reference comparison against value(s) derived from imaging modality measurement tools in orthogonal planes, whilst oblique measurements may be calculated by the application of geometrical relationships as applied to the CT measurement accuracy correction phantom, although it has to be appreciated that there are no lines or triangles used in the construction of the correction matrix and reference to them is purely by way of illustration only. Claim 2

Apparatus as claimed in Claim 1, wherein the universal imaging phantom in a non-configured form consists of a base frame for receiving phantom support column(s) which may be engaged and locked into place by locking pins in a singularity or a plurality, or an accessory phantom base plate may be engaged into the base frame and secured in by the said locking pins, or a combination of a singularity or a plurality of phantom support column(s) and an accessory phantom base plate may be selected for the attachment of and securing by means of locking pins, a range of attachments called modality specific accessory phantoms which are test phantoms designed to be imaged by a specific type of imaging process or imaging modality, and the image(s) generated will be dependent on the type of imaging technology used and the physical principle used to create the image(s), the optimised and time based method(s) of recording changes or collecting data within the dynamic processes of the image formation such that the image(s) generated will contain detailed information relating to the internal and external features of design and construction of the selected phantom, and the universal imaging phantom being the first functional component of all of the configurations of the universal imaging phantom, regardless of the numbers) andtype(s) of modality specific accessory phantom(s) comprising it.

Claim 3

Apparatus as claimed in Claim 1, wherein the universal imaging phantom is configured for measurement accuracy verification of computed tomography (CT) and its configuration comprises base frame, a singularity of phantom support column(s), x-axis and y-axis linear measurement tube(s) and a singularity or plurality of z-axis measurement tubes engaged and fastened into the octagonal socket(s) of the said support column(s), and locking pins for securing the phantom support column(s) to the base frame, such that when the universal imaging phantom for computed tomography (CT) is imaged it generates 2-Dimensional images (or planar or linear image(s) in discrete sectional thicknesses that may only be viewed on a display that only represents two dimensions of information at a time, namely x-axis and y-axis image data with little discernable appreciation of z-axis data or depth of image), or volumetric or 3-Dimensional images (planar and linear images recorded as a block of image data which may be dynamically viewed as a scrolling image that freely passes through the image block allowing viewing of the subject in any orientation, and may be viewed on a display where the image data can be freely re-orientated and at variable thickness of image), and where the computed tomography configuration of the said universal imaging phantom generates images of the modality specific accessory phantom in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, and such that the said accessory phantom for computed tomography may be used to provide an image(s) or series of images that may be viewed using the volumetric imaging display platforms of multi-planar reconstructions (MPR' s), maximum intensity projections (MIP's) and curved reconstructions, which are developed to enable non-linear structures to be viewed in totality and to be re-orientated in space to enable the image measurement tools to be able to effectively trace the outline of the structure and to record accurate measurements of diameter, area, volume and length, such that the value(s) of said parametric measurements may be compared against the measurement reference value(s) of the said accessory phantom thus evaluating the measurement accuracy of image measuring tools of the computed tomography scanner.

Claim 4

Apparatus as claimed in Claim 1, wherein the universal imaging phantom is configured for measurement accuracy verification of computed tomography (CT) and its configuration comprises a base frame with accessory phantom base plate secured by locking pins, and a modality specific accessory phantom for computed tomography (CT) slotted into the accessory phantom base plate such that when the universal imaging phantom for computed tomography (CT) is imaged it generates 2-Dimensional images (or planar or linear image(s) in discrete sectional thicknesses that may only be viewed on a display that only represents two dimensions of information at a time, namely x-axis and y-axis image data with little discernable appreciation of z-axis data or depth of image), or volumetric or 3 -Dimensional images (planar and linear images recorded as a block of image data which may be dynamically viewed as a scrolling image that freely passes through the image block allowing viewing of the subject in any orientation, and may be viewed on a display where the image data can be freely re-orientated and at variable thickness of image), and where the computed tomography configuration of the said universal imaging phantom generates images of the modality specific accessory phantom in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, and such that the said accessory phantom for computed tomography may be used to provide an image(s) or series of images that may be viewed using the volumetric imaging display platforms of multi-planar reconstructions (MPR's), maximum intensity projections (MIP's) and curved reconstructions, which are developed to enable non-linear structures to be viewed in totality and to be reorientated in space to enable the image measurement tools to be able to effectively trace the outline of the structure and to record accurate measurements of diameter, area, volume and length, such that the value(s) of said parametric measurements may be compared against the measurement reference value(s) of the said accessory phantom thus evaluating the measurement accuracy of image measuring tools of the computed tomography scanner, and additionally where the attenuation pattern of the dotted lines that compose the image(s) have specific appearances < and distance relationships in all of the three orthogonal (at 90 degrees to each other) imaging planes so that the capability of the scanner to generate the dotted straight lines of the said accessory phantom as it moves through the imaging field may be described as translational linearity, and also the capability of the scanner to construct image(s) that have spatial and positional accuracy such that the image(s) of the measuring rods are of the correct diameter and regular spacing and the parallel lines have a particular and constant value of distance separation, such the said accessory phantom evaluates the capability of the scanner to construct and present the five lines of dots parallel to each other throughout the length of the imaged object and this may be referred to as "parallelism" of an image(s), series of images or volumetric image dataset.

Claim 5

Apparatus as claimed in Claim 1, wherein the universal imaging phantom is configured for measurement accuracy verification of computed tomography (CT) and its configuration comprises base frame, an accessory phantom base plate, a singularity or plurality of phantom support column(s), x-axis and y-axis linear measurement tube(s) and a singularity or plurality of z-axis measurement tubes engaged and fastened into the octagonal socket(s) of the said support column(s), and locking pins for securing the phantom support column(s) and accessory phantom base plate to the base frame and the modality specific accessory phantom for computed tomography (CT), such that when the universal imaging phantom for computed tomography (CT) is imaged it generates 2-Dimensional images (or planar or linear image(s) in discrete sectional thicknesses that may only be viewed on a display that only represents two dimensions of information at a time, namely x-axis and y-axis image data with little discernable appreciation of z-axis data or depth of image), or volumetric or 3-Dimensional images (planar and linear images recorded as a block of image data which may be dynamically viewed as a scrolling image that freely passes through the image block allowing viewing of the subject in any orientation, and may be viewed on a display where the image data can be freely re-orientated and at variable thickness of image), and where the computed tomography configuration of the said universal imaging phantom generates images of the modality specific accessory phantom in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, and such that the said accessory phantom for computed tomography may be used to provide an image(s) or series of images that may be viewed using the volumetric imaging display platforms of multi-planar reconstructions (MPR's)," maximum intensity projections (MIP's) and curved reconstructions, which are developed to enable non-linear structures to be viewed in totality and to be reorientated in space to enable the image measurement tools to be able to effectively trace the outline of the measuring tube(s) and the modality specific accessory phantom for computed tomography (CT) and to record accurate measurements of diameter, area, volume and length, such that the value(s) of said parametric measurements may be compared against the measurement reference value(s) of the said accessory phantom(s) and to further assess the capability of the scanner to generate the dotted straight lines of the said accessory phantom as it moves through the imaging field that may be described as translational linearity, and also the capability of the scanner to construct image(s) that have spatial and positional accuracy such that the image(s) of the measuring rods are of the correct diameter and regular spacing and the parallel lines have a particular and constant value of distance separation, such the said accessory phantom evaluates the capability of the scanner to construct and present the five lines of dots parallel to each other throughout the length of the imaged object and this may be referred to as "parallelism" of an image(s), series of images or volumetric image dataset, thus evaluating the measurement accuracy of image measuring tools of the computed tomography scanner.

Claim 6

Apparatus as claimed in Claim 1, wherein the universal imaging phantom is configured for measurement accuracy verification of magnetic resonance imaging (MRI) and its configuration comprises base frame, phantom support column(s), x-axis and y-axis linear measurement tube(s), z-axis measurement tube(s) and locking pins for securing the phantom support column(s) to the base frame, such that when the universal imaging phantom for magnetic resonance imaging (MRI) is imaged it generates 2-Dimensional images (or planar or linear image(s) in discrete sectional thicknesses that may only be viewed on a display that only represents two dimensions of information at a time, namely x-axis and y-axis image data with little discernable appreciation of z-axis data or depth of image), or volumetric or 3-Dimensional images (planar and linear images recorded as a block of image data which may be dynamically viewed as a scrolling image that freely passes through the image block allowing viewing of the subject in any orientation, and may be viewed on a display where the image data can be freely re-orientated and at variable thickness of image), and where the computed tomography configuration of the said universal imaging phantom generates images of the modality specific accessory phantom in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, and such that the resolution and image quality may be increased by encasement of the said accessory phantom in the magnetic resonance tank enclosure and immersed in water, thus improved image quality so that the said accessory phantom for magnetic resonance imaging may be used to provide an image(s), series of images or volume of image data that may be viewed using the volumetric imaging display platforms of multi-planar reconstructions (MPR's), maximum intensity projections (MIP's) and curved reconstructions, which are developed to enable non-linear structures to be viewed in totality and to be re-orientated in space to enable the image measurement tools to be able to effectively trace the outline of the structure and to record accurate measurements of diameter, area, volume and length, such that the value(s) of said parametric measurements may be compared against the measurement reference value(s) of the said accessory phantom thus evaluating the measurement accuracy of image measuring tools of the magnetic resonance imaging scanner.

Claim 7

Apparatus as claimed in Claim 1, wherein the universal imaging phantom is configured for measurement accuracy verification of digital subtraction angiography (DSA) and radio- fluoroscopy (RF) and its configuration comprises base frame, phantom support column(s), x-axis and y-axis linear measurement tube(s) and a singularity or plurality of z-axis measurement tubes engaged and fastened into the octagonal socket(s) of the said support column(s), and locking pins for securing the phantom support column(s) to the base frame, such that when the universal imaging phantom for digital subtraction angiography (DSA) and radio-fluoroscopy (RF) is imaged it generates 2-Dimensional images (or planar or linear image(s) in discrete sectional thicknesses that may only be viewed on a display that only represents two dimensions of information at a time, namely x-axis and y-axis image data with little discernable appreciation of z-axis data or depth of image), and where the digital subtraction angiography (DSA) or radio- fluoroscopy (RF) configuration of the said universal imaging phantom generates images of the modality specific accessory phantom in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, and such that the said accessory phantom for digital subtraction angiography or radio-fluoroscopy may be used to provide an image(s) or series of images that may be viewed using the 2-Dimensional or planar image displays that only allows x- axis and y-axis image date to be displayed regardless of the orientation or plane of view of the subject, and where the image measurement tools may be used to measure values of diameter, area, volume and length of the said accessory phantom, and such that for any planar view of the said universal imaging phantom, an adjustment for magnification is required to be made using the central wire of the x, y and z measurement tubes for a calibrated millimetre and centimetre scale available for reference purposes and contained within the image(s), an where ultimately the value(s) of the said parametric measurements may be compared against the measurement reference value(s) of the said accessory phantom thus evaluating the measurement accuracy image measuring tools of the digital subtraction angiography (DSA) and radio-fluoroscopy (RF) imaging apparatus.

Claim 8

Apparatus as claimed in Claim 1, wherein the universal imaging phantom is configured for measurement accuracy verification of computed tomography (CT) and nuclear (isotope) imaging (NI) and its configuration comprises base frame, an accessory phantom base plate, a singularity or plurality of phantom support column(s), x-axis and y-axis linear measurement tube(s) and a singularity or plurality of z-axis measurement tubes engaged and fastened into the octagonal socket(s) of the said support column(s), and locking pins for securing the phantom support column(s) and accessory phantom base plate to the base frame and the modality specific accessory phantom for nuclear (isotope) imaging (NI), such that when the universal imaging phantom for computerised tomography (CT) and nuclear (isotope) imaging (NI) is imaged it generates both 2-Dimensional images (or planar or linear image(s) in discrete sectional thicknesses that may only be viewed on a display that only represents two dimensions of information at a time, namely x-axis and y-axis image data with little discernable appreciation of z-axis data or depth of image), and volumetric or 3-Dimensional images (planar and linear images recorded as a block of image data which may be dynamically viewed as a scrolling image that freely passes through the image block allowing viewing of the subject in any orientation, and may be viewed on a display where the image data can be freely re-orientated and at variable thickness of image), and where the computerised tomography (CT) and nuclear (isotope) imaging (NI) configurations of the said universal imaging phantom generates image(s) of the modality specific accessory phantoms for both in turn in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, and where that the said accessory phantom for computed tomography (CT) may be used to provide an image(s) or series of images that may be viewed using the volumetric imaging display platforms of multi-planar reconstructions (MPR' s), maximum intensity projections (MIP's) and curved reconstructions, which are developed to enable non-linear structures to be viewed in totality and to be re-orientated in space to enable the image measurement tools to be able to effectively trace the outline of the measuring tube(s) and to record accurate measurement(s) of diameter, area, volume and length, so that the value(s) of the said parametric measurements may be compared against the measurement reference value(s) of the said accessory phantom(s) thus evaluating the measurement accuracy of image measuring tools of the computed tomography scanner, and where evaluation of the image(s) generated by the nuclear (isotope) imaging machine evaluates the ability of the scintillation and imaging apparatus to collect gamma radiation, register as a correctly positioned and spatially accurate "hot-spot" or small diameter dot of typically 2 millimetres diameter and to present a plurality of these hot-spots as accurately positioned and equidistant with clearly defined centre to centre spatial separation of typically 40 millimetres from its neighbouring hot-spot in the same line and with all lines of hot-spots being separated by 100 millimetres in all of the orthogonal imaging planes, giving an assessment of the capabilities of the nuclear (isotope) imaging (NI) apparatus to provide images that have good accuracy of positioning and spatial separation in all three orthogonal imaging planes.

Claim 9

Apparatus as claimed in Claim 1, wherein the universal imaging phantom is configured for measurement accuracy verification of nuclear (isotope) imaging (NI) and its configuration comprises base frame, an accessory phantom base plate, and locking pins for securing the accessory phantom base plate to the said base frame, and the modality specific accessory phantom for nuclear (isotope) imaging (NI) engaged into the locator groove of the said accessory phantom base plate, and if preferred the further engagement of one or two modality specific side mounted accessory phantom (s) with the locator groove(s) of the said modality specific accessory phantom for nuclear (isotope) imaging facilitating a single, two, three of four lined array to be constructed, so that when the universal imaging phantom configured for nuclear (isotope) imaging (NI) is imaged, it generates 2-Dimensional images (or planar, linear image(s) that may only be viewed on a display that only represents two dimensions of information at a time, namely x-axis and y-axis image data with little discernable appreciation of z-axis data or depth of image), and such that the nuclear (isotope) imaging (NI) configuration of the said universal imaging phantom generates image(s) of the said modality specific accessory phantom(s) in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, and where that the evaluation of the image(s) generated by the nuclear (isotope) imaging machine evaluates the ability of the scintillation and imaging apparatus to collect gamma radiation, register as a correctly positioned and spatially accurate "hot-spot" or small diameter dot of typically 2 millimetres diameter, and to present a plurality of these hot-spots as accurately positioned and equidistant with clearly defined centre to centre spatial separation of typically 40 millimetres from its neighbouring hot-spot in the same line and with all lines of hot- spots being separated by 100 millimetres in all of the orthogonal imaging planes, giving an assessment of the capabilities of the nuclear (isotope) imaging (NI) apparatus to provide images that have good accuracy of positioning and spatial separation in all three orthogonal imaging planes.

Claim 10

Apparatus as claimed in Claim 1, wherein the universal imaging phantom is configured for measurement accuracy verification of computed radiography (CR) and its configuration comprises base frame, modality specific accessory phantom for computer radiography (CR) and locking pins for securing the said accessory phantom to the base frame, and where if preferred, a singularity or plurality of phantom support column(s), x-axis and y-axis linear measurement tube(s) and a singularity or plurality of z-axis measurement tubes engaged and fastened into the octagonal socket(s) of the said support column(s), and locking pins for securing the phantom support column(s) to the said base frame, such that when the universal imaging phantom configured for computed radiography (CR) is imaged, it creates an image of all of the internal components and measurement marker included in the said accessory phantom which includes a number of functional markings, lines and edge indicators, the lines forming a square on the bottom aspect of the base of typically 350 millimetres length by 190 millimetres width, where a diagonal line is drawn from each corner to form four triangular sections, another two lines are drawn from the midpoint of each edge to the centre of the base dividing each of the triangular sections into two, this in itself forms smaller triangular areas across the base area, where along each of these bisecting lines and extending to the edges of the plate are linear scales measured in metric or Imperial sub-divisions of a metre or a foot respectively, so that typically in the case of a metric scaled base, these subdivisions would be in millimetres and centimetres and extending from the centre point at zero radially to their respective maximum values, and in the case of an Imperial scaled base, these sub-divisions would be in inches or less, and where at each of the four corners of base and at a point typically 90 millimetres above and below the longitudinal (or horizontal) centre line, and 175 millimetres to the left and right of the transverse (or vertical) centre line are four corner identifiers, each set comprising right angled lines of typically 30 millimetres length serving to delineate the corners of the base for an X-ray field collimation area test (or area of defined X-radiation exposure), and where on the base there is defined a circle at the geometrical centre of the accessory module for the vertical central ray of the X-ray tube to be centred prior to radiographic exposure, and which serves as a point of centring for the applied X- radiation beam to the said accessory phantom for measurement of computed radiography (CR) images, and ensuring minimal distortion and parallax in the image(s) generated, and where in every other triangular section of the module, and inlaid into the polymer substance are functional test units for assessment of image distortion in the form of a geometrical shape module to evaluate distortion in an image, measurement of resolution and Modulation Transfer Function (MTF) in the form of a line pairs per centimetre module, sensitometric type testing of the image plate recording system by use of an incorporated wedge filter, and symmetrical square references for further image distortion evaluation, and image contrast references, where each of the densities of the squares from number 1 to 8 has a respective thickness and calibrated effect of reducing radiographic densities across the area of the imaging plate, such that if the contrast level(s) were measured from 1 to 8, the measurements when obtained and plotted on a graph would give a linear relationship of contrast index against the square reference number, and where such testing may be carried out using an added filter equivalent to 1 millimetre of copper to harden the X-radiation beam and absorb lower energy wavelength radiation that may reduce the image contrast levels in the image(s) generated, using a prescribed or standardised test exposure at a specified (focus to image plate distance) to reduce the effects of variation(s) in image quality as a result of differences in X-radiation beam characteristics, and further where the imaging plate(s) used for recording the latent or stored image(s) are solely used for quality assurance (QA) testing and read or interrogated using a specified computed radiography imaging plate reader of known performance, and additionally where image(s) of the said x-axis and y-axis linear measurement tube(s) indicate peripheral image distortion of the image(s) and the level of magnification at a given height above the imaging plate of the computed radiography (CR) imaging system, and the z-axis measurement tubes may give an assessment of distortion of shape of the particular shaped accessory phantom and deviation of distance between the radio-opaque markers and where the image(s) generated are 2-Dimensional images (or planar, linear image(s) that may only be viewed on a display that only represents two dimensions of information at a time, namely x-axis and y-axis image data with little discernable appreciation of z-axis data or depth of image), and such that the modality specific accessory phantom for computed radiography (CR) configuration of the said universal imaging phantom generates image(s) of the said modality specific accessory phantom(s) in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, thus evaluating the measurement accuracy of image measuring tools of the computed radiography (CR) imaging system,

Claim 11

Apparatus as claimed in Claims 1 and 10, wherein the universal imaging phantom is configured for measurement accuracy verification of computed radiography (CR) and its configuration comprises base frame, modality specific accessory phantom for computer radiography (CR) and locking pins for securing the said accessory phantom to the base frame, such mat when the universal imaging phantom configured for computed radiography (CR) is imaged, it creates an image of all of the internal components and measurement markers) included in the said accessory phantom which includes a number of functional markings, lines and edge indicators, the lines forming a square on the bottom aspect of the base of typically 350 millimetres length by 190 millimetres width, where a diagonal line is drawn from each corner to form four triangular sections, another two lines are drawn from the midpoint of each edge to the centre of the base dividing each of the triangular sections into two, this in itself forms smaller triangular areas across the base area, where along each of these bisecting lines and extending to the edges of the plate are linear scales measured in metric or Imperial sub-divisions of a metre or a foot respectively, so that typically in the case of a metric scaled base, these subdivisions would be in millimetres and centimetres and extending from the centre point at zero radially to their respective maximum values, and in the case of an Imperial scaled base, these sub-divisions would be in inches or less, and where at each of the four corners of base and at a point typically 90 millimetres above and below the longitudinal (or horizontal) centre line, and 175 millimetres to the left and right of the transverse (or vertical ) centre line are four corner identifiers, each set comprising right angled lines of typically 30 millimetres length serving to delineate the corners of the base for an X-ray field collimation area test (or area of defined X-radiation exposure), and where on the base there is defined a circle at the geometrical centre of the accessory module for the vertical central ray of the X-ray tube to be centred prior to radiographic exposure, and which serves as a point of centring for the applied X-radiation beam to the said accessory phantom for measurement of computed radiography (CR) images, and ensuring minimal distortion and parallax in the image(s) generated, and where in every other triangular section of the module, and inlaid into the polymer substance are functional test units for assessment of image distortion in the form of a geometrical shape module to evaluate distortion in an image, measurement of resolution and Modulation Transfer Function (MTF) in the form of a line pairs per centimetre module, sensitometric type testing of the image plate recording system by use of an incorporated wedge filter, and symmetrical square references for further image distortion evaluation, and image contrast references, where each of the densities of the squares from number 1 to 8 has a respective thickness and calibrated effect of reducing radiographic densities across the area of the imaging plate, such that if the contrast level(s) were measured from 1 to 8, the measurements when obtained and plotted on a graph would give a linear relationship of contrast index against the square reference number, and where such testing may be carried out using an added filter equivalent to 1 millimetre of copper to harden the X-radiation beam and absorb lower energy wavelength radiation that may reduce the image contrast levels in the image(s) generated, using a prescribed or standardised test exposure at a specified (focus to image plate distance) to reduce the effects of variations) in image quality as a result of differences in X-radiation beam characteristics, and further where the imaging plate(s) used for recording the latent or stored image(s) are solely used for quality assurance (QA) testing and read or interrogated using a specified computed radiography imaging plate reader of known performance, and such that the modality specific accessory phantom for computed radiography (CR) configuration of the said universal imaging phantom generates image(s) of the said modality specific accessory phantom(s) in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, thus evaluating the measurement accuracy of image measuring tools of the computed radiography (CR) imaging system, which may be further applied to image(s) transferred over networks and as such the said accessory phantom may be used to produce test image(s) whose structural design produces a range of parametric reference value(s) as part of the image, and may be used to evaluate image(s) retrieved from picture archive and communications systems (PACS), networked image transfer systems and teleradiology systems using digital imaging and communications in medicine (DICOM) or other accepted image transfer standards, and where images retrieved on remote viewing facilities may use their image measurement tools to measure the image of the said accessory phantom and comparing the obtained measurement values against the reference value(s) of the universal imaging phantom configured for computed radiography (CR).

Claim 12

Apparatus as claimed in Claim 1, wherein the universal imaging phantom is configured for measurement accuracy verification of computed radiography (CR) and its configuration comprises base frame, modality specific accessory phantom (tubular) for computed radiography (CR), and locking pins for securing the said accessory phantom to the base frame, and where the said modality specific accessory phantom (tubular) consists of an oblong frame used for the supporting of measurement tube(s) used in the accessory phantom that may be inserted into the base frame and whose dimensions are typically 408 millimetres long by 198 millimetres width, and 20 millimetres thickness, and where the frame is typically divided unequally into three sections, the first section having its point of origin 123 millimetres from the vertical edge of the left sided column and bounded by a vertical column extending from one longitudinal edge to another, forming a section on the left side of the construction called the main vertical window of the accessory module, where situated at the midpoint of the vertical column is a horizontal column typically 20 millimetres square, which extends to join with the transverse column of the right side of the frame construction, the horizontal column dividing the remaining space into two equal portions, a lower section called the lower horizontal window of the accessory module, and an upper section called the upper horizontal window of the accessory module, and where by way of example only, the horizontal column would originate from a point 79 millimetres from the base of the section, the main vertical window would be 160 millimetres transversely and 1 13 millimetres longitudinally, and the two divided smaller sections would be 69 millimetres transversely by 235 millimetres longitudinally, and where at various positions on the lateral surface of the longitudinal edges of the frame, and spaced 40 millimetres apart, are 30 millimetre deep holes perpendicularly into the material of the base plate which correspond to the spacing of holes on the lateral aspects of the longitudinal members of the base frame, where an unthreaded nylon or other suitable non-magnetic material headed locking pin may then be placed into each of the two holes to allow the base plate accessory module to be fixedly or releasably and / or variably secured together with the base frame, and where said frame has a number of retaining clips for holding specified diameter linear measuring tube(s) in longitudinal, transverse or oblique planes, and where by way of example only, the typical diameter(s) for the transverse measurement tube(s) would be 20 millimetres and the tube length 140 millimetres for the left hand vertical tubes, and where this section would typically incorporate three of the oblique measurement tubes of differing cross-sectional diameters) and length(s) of imaging column, and in the upper right hand section of the frame that carries the longitudinal measuring tubes, the tube diameters) would typically be 25, 20, 15 and 10 millimetres cross-section and of tube length 215 millimetres, and would incorporate four measurement tubes of differing cross- sectional diameter(s) and length(s) of imaging column, the lower right hand section carrying the obliquely mounted measuring tubes, would typically require similar diameter measurement tubes of 20, 10 and 5 millimetres cross-sectional diameters) and of typical length variations between 235 -160 millimetres length, but with different lengths of imaging column, and by which the mounting or securing of these said measurement tube(s) in their defined and relative positions, is by the provision of wedges shaped into the construction at certain positions in the construction that hold the supporting clips, and whereby the final construction once assembled can be mounted into the base frame and secured into position with the retaining pins located into the recesses on the said accessory phantom, where each of the measuring tubes will have an imaging volume of fluid contained in the body, and the column length of each tube can be varied according to the preferred choices, such that typically, in the left hand section a 140, 100 and 60 millimetres length selection are used, and in the top right hand section, typically 215, 175, 135 and 100 millimetres length selection is used, and in the lower right hand section, typically 235, 175, and 100 millimetres length selection is used, and such that when the universal imaging phantom (tubular) configured for computed radiography (CR) is imaged, it generates image(s) of the said modality specific accessory phantom(s) in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, thus evaluating the measurement accuracy of image measuring tools of the computed radiography (CR) imaging system.

Claim 13

Apparatus as claimed in Claim 1, wherein the universal imaging phantom is configured for measurement accuracy verification and correction of computerised tomography (CT) and its configuration comprises base frame, a singularity of phantom support column(s), x-axis and y- axis linear measurement tube(s) and a singularity or plurality of z-axis measurement tubes engaged and fastened into the octagonal socket(s) of the said support column(s), locking pins for securing the phantom support column(s) to the base frame, and the modality specific measurement accuracy correction phantom for computed tomography (CT), such that when the universal imaging phantom for computed tomography (CT) is imaged it generates 2-Dimensional images (or planar or linear image(s) in discrete sectional thicknesses that may only be viewed on a display that only represents two dimensions of information at a time, namely x-axis and y-axis image data with little discernable appreciation of z-axis data or depth of image), or volumetric or 3-Dimensional images (planar and linear images recorded as a block of image data which may be dynamically viewed as a scrolling image that freely passes through the image block allowing viewing of the subject in any orientation, and may be viewed on a display where the image data can be freely re-orientated and at variable thickness of image), and where the computed tomography configuration of the said universal imaging phantom generates images of the modality specific accessory phantom in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, and such that the said accessory phantom for computed tomography may be used to provide an image(s) or series of images that may be viewed using the volumetric imaging display platforms of multi-planar reconstructions (MPR' s), maximum intensity projections (MIP' s) and curved reconstructions, which are developed to enable nonlinear structures to be viewed in totality and to be re-orientated in space to enable the image measurement tools to be able to effectively trace the outline of the structure and to record accurate measurements of diameter, area, volume and length, such that the value(s) of said parametric measurements may be compared against the measurement reference value(s) of the said accessory phantom thus evaluating the measurement accuracy of image measuring tools of the computed tomography scanner, but equally where in the normal imaging and measuring of image(s) an additional set of reference value(s) may be accessed and which may be applied to all image measurement situations, and where the accessory measurement accuracy correction tool for computed tomography (CT) is designed to work in conjunction with the base frame and measurement tube(s) assemblies, or in isolation underneath the object or region(s) of interest, as in the case by way of example only, where the said measurement accuracy correction phantom may be integrated unobtrusively into the body of the imaging table of the computed tomography (CT) apparatus, and the said modality specific measurement accuracy correction phantom for computed tomography (CT) is used to generate a 1 centimetre cubical reference matrix as a component in an image and below the subject or phantom being imaged such, that the image of the said matrix is integrated with image(s) of the universal imaging phantom configured for computed tomography (CT) and containing the preferred modality specific accessory phantom(s) that may be accessed if required by dropping the viewing plane to a point below that of the said modality specific accessory phantom for computed tomography (CT), and where the construction of the said measurement accuracy correction phantom is made from perspex (RTM), acrylic or other radiolucent and non-magnetic material frame and shaped by way of example only into an oblong shape, and where the said measurement accuracy correction phantom comprises a number of not less than two, and typically not more than five planar single sections, in order that the added inertia to the table is minimised, and that table indexing and movement characteristics are not altered, and where each complete sectional layer is typically of such a thickness that a 2 millimetre, 5 millimetre, 10 millimetre or otherwise diameter hyper- dense sphere of low to moderate x-ray attenuation can be embedded into the middle of the section at a plurality of appropriately positioned and linearly related loci across the surface of the material to form lines of reference on the said section(s), and where the separation of these hyper dense spheres is typically 10 millimetres transversely and longitudinally from each of their respective centres so forming a 10 millimetre square matrix covering the larger aspect of the upper surface of the section, and where by way of example only, the spheres are arranged such that the first and last sphere is 2 millimetres diameter along the longitudinal length and the transverse width of the whole of the said measurement accuracy correction phantom in that specified layer and all other layers except the middle layer which is different in that it is composed of two separate longitudinal lines at the most lateral or outer points of the construction and the reference matrix, with each said line having embedded in them 10 millimetre diameter hyperdense spheres of low to moderate x-ray attenuation which are offset by 10 millimetres distance and generally separated by 20 millimetres distance, with the rest of the longitudinal lines at all other levels being composed of 2 millimetre diameter spheres and with 10 millimetres separation to give general continuity throughout the correction matrix, and where the function of the 10 millimetre hyperdense spheres are for reference purposes and are present only to delineate the most lateral or outer edge of the correction matrix, and the use of an additional number(s) of similarly sized and shaped sections placed squarely, closely and fixedly to the said section(s) will provide an overall thicker sectional construction and correction matrix, and where on one or both ends of the sectional construction is a section containing a range of disks of increasing diameter and depth whose function is to give length reference to the electronic cursor measurements of known diameter planar disks of 25, 20, 15, 10, 2 millimetres diameter, and functions to provide a selection of reference diameter(s) to test the image measurement tools for their abilities to measure diameter(s) and depths in different orthogonal planes, and such that the image(s) of the correction matrix is based on a 1 centimetre cube and at its most basic the distance relationship between the centres of a single sphere to the centre of the next should be 1 centimetre in longitudinal, transverse and vertical directions, and if the point of reference was to be taken from the centre of one sphere to the centre of another obliquely, then the distance would be the square root of 2 which is 1.414 centimetres, noting strictly that there are no direct references to actual triangles within the structure since the correction metric can only function from 1 centimetre cubes or from multiples thereof in any direction and any reference made to geometrical relationships are purely in the interests of quick calculation of length, and by way of example only, a 3 centimetre line of reference drawn across four spheres and a 4 centimetre line drawn across five spheres will have a line that joins them that passes through six of the spheres obliquely and will have a length of five centimetres, such imaging generates images of the modality specific measurement accuracy correction phantom in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, so that measurements) performed on the universal imaging phantom configured for computed tomography (CT) may be checked for plane related discrepancies thus evaluating the measurement accuracy of image measuring tools of the computerised tomography (CT) scanner.

Claim 14

Apparatus as claimed in Claim 1, wherein the universal imaging phantom is configured for measurement accuracy verification and correction of magnetic resonance imaging (MRI) and its configuration comprises base frame, a singularity of phantom support column(s), x-axis and y- axis linear measurement tube(s) and a singularity or plurality of z-axis measurement tubes engaged and fastened into the octagonal socket(s) of the said support column(s), locking pins for securing the phantom support column(s) to the base frame, and the modality specific measurement accuracy correction phantom for magnetic resonance imaging (MRI), and the magnetic resonance imaging tank enclosure for higher quality imaging if preferred, and such that when the universal imaging phantom for magnetic resonance imaging (MRI) is imaged it generates 2 -Dimensional images (or planar or linear image(s) in discrete sectional thicknesses that may only be viewed on a display that only represents two dimensions of information at a time, namely x-axis and y-axis image data with little discernable appreciation of z-axis data or depth of image), or volumetric or 3-Dimensional images (planar and linear images recorded as a block of image data which may be dynamically viewed as a scrolling image that freely passes through the image block allowing viewing of the subject in any orientation, and may be viewed on a display where the image data can be freely re-orientated and at variable thickness of image), and where the computed tomography configuration of the said universal imaging phantom generates images of the modality specific accessory phantom in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, and such that the said accessory phantom for computed tomography may be used to provide an image(s) or series of images that may be viewed using the volumetric imaging display platforms of multi-planar reconstructions (MPR's), maximum intensity projections (MIP's) and curved reconstructions, which are developed to enable non-linear structures to be viewed in totality and to be re-orientated in space to enable the image measurement tools to be able to effectively trace the outline of the structure and to record accurate measurements of diameter, area, volume and length, such that the value(s) of said parametric measurements may be compared against the measurement reference value(s) of the said accessory phantom thus evaluating the measurement accuracy of image measuring tools of the computed tomography scanner, but equally where in the normal imaging and measuring of image(s) an additional set of reference value(s) may be accessed and which may be applied to all image measurement situations, and where the accessory measurement accuracy correction tool for magnetic resonance imaging (MRI) is designed to work in conjunction with the base frame and measurement tube(s) assemblies, or in isolation underneath the object or region(s) of interest, as in the case by way of example only, where the said measurement accuracy correction phantom may be integrated unobtrusively into the body of the imaging table of the magnetic resonance imaging (MRI) apparatus, and the said modality specific measurement accuracy correction phantom for magnetic resonance imaging (MRI) is used to generate a 15 millimetre cubical reference matrix as a component in an image and below the subject or phantom being imaged, such that the image of the said matrix is integrated with image(s) of the universal imaging phantom configured for magnetic resonance imaging (MRI) and containing the preferred modality specific accessory phantom(s) that may be accessed if required by dropping the viewing plane to a point below that of the said modality specific accessory phantom for magnetic resonance imaging (MRI), and where the construction of the said measurement accuracy correction phantom is made from perspex (RTM), acrylic or other radiolucent and nonmagnetic material frame and shaped by way of example only into an oblong shape, and where the said measurement accuracy correction phantom comprises a number of not less than two, and typically not more than five planar single sections, in order that the added inertia to the table is minimised, and that table indexing and movement are not altered, and each complete sectional layer is typically of a thickness that a 5 millimetre or otherwise diameter sphere of oil or other magnetic resonance signal generating fluid is embedded into the middle of the two sections and in an indentation on each upper and lower surface at a plurality of appropriately positioned and linearly related loci across the surface of the material to form lines of reference on the said section(s), and where the separation of these oil spheres is typically 15 millimetres longitudinally and transversely from each of their respective centres so as to form a 15 millimetre cubical matrix covering the larger aspect of the upper surface of the section, and where by way of example only, the oil spheres are arranged such that the first and last sphere is 5 millimetres diameter with a spatial separation of 15 millimetres longitudinally and a transverse width separation of 15 millimetres across the whole of the said measurement accuracy correction phantom in that specified layer and all other layers forming the construction forming the correction matrix, and such that following imaging, access to image(s) of the measurement correction phantom is similar to that for the CT measurement accuracy correction phantom and the 15 millimetre matrix may be accessed by dropping the plane of viewing below the subject being measured, where lines drawn between the centre points of each oil capsule longitudinally, transversely and vertically will give measurement accuracy reference comparison against value(s) derived from imaging modality measurement tools in orthogonal planes, whilst oblique measurements may be calculated by the application of geometrical relationships as applied to the CT measurement accuracy correction phantom, although it has to be appreciated that there are no lines or triangles used in the construction of the correction matrix and reference to them is purely by way of illustration only, and where imaging of the said modality specific measuring accuracy correction phantom in a required position in the apparatus; forming an image(s), or series of images of die reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, and where that the evaluation of the image(s) generate value(s) that may be compared to the known references in the correction matrix thus evaluating the measurement accuracy of image measuring tools of the magnetic resonance (MRI) scanner. Claim 15

Apparatus as claimed in Claim 1, wherein the universal imaging phantom may be selectively configured for the modality specific testing of a wide range of radiological imaging machines and the image(s) generated of the said modality specific accessory phantom, or modality specific measuring accuracy correction phantom in a required position in the apparatus; forming an image(s), or series of images of the reference tool and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, may be applied to all situations involving the measurement accuracy of image measuring tools found on 2-Dimensional or planar image viewing displays which are only capable of presenting an image(s) that contain x-axis and y-axis image data and very little z-axis image data such that the image lacks any real depth of image and image(s) exist as discreet sections of defined length and width but with no real thickness, and where more particularly the image(s) produced by the universal imaging phantom is specifically designed to enable evaluation of measurement accuracy of image measuring tools found on image displays of computerised tomography (CT) and magnetic resonance imaging (MRI) scanners where the image(s) generated are 3-Dimensional or volumetric images which are designed to display image data in x-axis, y-axis and z-axis, such that the image may be viewed in any viewing plane or image orientation and the image may be readily scrolled through in discreet sections of a defined thickness, and which can be reconstructed in any orientation and in any preferred thickness, and such that imaging of the modality specific accessory phantom or modality specific measuring accuracy correction phantom in a required position in the apparatus; forming an image(s), or series of images of the reference tool(s) and obtaining at least one measurement thereof from the image; and comparing the at least one measurement thus obtained with at least one known measurement of the tool, and where that the evaluation of the image(s) generate value(s) that may be compared to the known references in the modality specific accessory phantom or the modality specific measurement accuracy correction phantom thus evaluating the measurement accuracy of image measuring tools of the respective radiological imaging machine and the respective configuration of the universal imaging phantom.