GB2075810A

GB2075810A - Radiological examination apparatus

Info

Publication number: GB2075810A
Application number: GB8039109A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-05-09
Filing date: 1980-12-05
Publication date: 1981-11-18
Also published as: DE3102625C2; FR2481919B1; DE3102625A1; CA1158784A; FR2481919A1; GB2075810B

Abstract

Radiological examination apparatus has a base 20 carrying U-shaped supports 12, 14 with arms 22, 24, (34, Figure 3), 36 for mounting a plurality of radiation sources 30, such as X-ray tubes, and radiation receptors 32, such as X-ray film plate holders. The U- shaped supports 12, 14 are rotatable about a common axis "A" with respect to each other. The axis "A" aligns with a subject on a rotatable table "T" and the sources 30 and receptors 32 have a common isocenter ("C") on the axis "A". Each radiation source 30 and its associated radiation receptor 32 is adjustable with a system (40, Figure 4) of cables, pulleys and counterweights to move radially inwardly and outwardly with respect to the common axis of rotation "A" to vary the radiation imagery. Simultaneous or sequential radiological examination can be performed from all angles inwardly of an imaginary sphere with its center at the isocenter ("C"). <IMAGE>

Description

SPECIFICATION Radiological examination apparatus 'The present invention relates to radiological exami nation apparatus, and more particularly to apparatus for supporting and maneuvering a plurality of radia stion, e.g. X-ray, sources and receptors to permit simultaneous or sequential exposure for the exami nation of different planes of a subject such as an organ of a patient.

Arteriography is a technique in which blood vessels and organs are injected with an opaque contrast medium to be used for diagnosis. Radio grams are made of the injected area to detect the flow of the contrast medium through and around the suspected entity. Various types of tumors and other disorders are thereby differentiated. Radiotopogra phy is a technique wherein a radioisotope is injected into the area under study and a scintillation camera measures the distribution of the isotope in and around the suspected lesion. Minimizing the quanti ty of contrast mediums or radioisotopes injected into the subject is naturally the most desired course of examination, while maximizing the quantity of film exposure of the subject over a wide range of angles with minimum discomfort to the patient.

A number of devices have been deviced over the years to facilitate radiological examination. An early attempt is shown in U.S. Patent Specification 1,599,696 (Wantz) wherein an X-ray apparatus com prises a single X-ray tube in movable cooperation with a fluorescent screen, on a circular frame arranged around a patient to be studied. The early Wantz apparatus did not provide for variation in distances between cooperating elements in the system and/or the patient being examined and in combination with the examining table shown, was somewhat cumbersome without facilitating the wide range of radiography desired. Another apparatus is described in U.S. Patent Specification 2,167,116 (Kieffer) wherein a single X-ray source is provided with a spherical surface of movement concommitant with the film, avoiding arcuate movement in a single plane.A further apparatus described in U.S Patent Specification 2,818,510 (Verse) wherein a wheeled carriage supports annular rings which guide an X-ray tube and luminoscope to concentrically encircle an object to be studied. The rings are however driven by large gear mechanisms which move the X-ray generator and receiver through their path. U.S Patent Specification 3,281,598 (Hollstein) describes apparatus with a C-shaped arm holding a single X-ray generator and receiving unit thereon, which arm is movable in conjunction with an overhead support system through a cumbersome vertical arm member, A more recent apparatus for radiological examination is described in U.S.Patent Specification 3,892,967 (Grady et al), wherein a movable U-shaped arm has its intermediate portion in linkage arrange ment comprising a parallelogram to provide a spherical locus of points for an X-ray generator and the radiation receptor. None of the prior art permits taking exposures in two planes simultaneously or sequentially so that a single injection of contrast medium can be utilized in the examination nor does the prior art disclose the interlocking of two X-ray tubes or similar radioactive elements in predetermined radial positions while allowing joint motion of two radiation means about an axis of rotation.

Interlocking allows rotating the two means simultaneously around an isocenter to sequentially take biplanar exposures of an organ and enables the examiner to view the functioning of that organ.

It is therefore an object of the present invention to provide improved apparatus which will permit simultaneous or sequential radiological examination of a subject on two planes by a plurality of radiological examination devices and minimize the exposure level of radioisotopes and contrast mediums within the subject.

In its broadest aspect radiological examination apparatus constructed in accordance with the invention comprises supports which each carry radiation means including a radiation source and a radiation receptor; each of said supports being independently rotatable about a common axis of rotation which can be aligned with the subject during examination.

In another aspect of the invention radiological examination apparatus comprises a base, first and second supports mounted on the base to rotate independently about a common axis, each support having two arms extending parallel to said common axis, a radiation source and a radiation receptor mounted at the respective ends of the arms of each support, the radiation sources and receptors having a radiation axis which intersect at a common isocenter on the common axis of rotation.

The invention also provides apparatus comprising an arrangement of support arms which each carry radiation means including a radiation source and a radiation receptor; a common axis of rotation for each of said support arms, said axis of rotation in alignment with said subject being examined; said support arms being rotatable with respect to each other, about said axis of rotation.

In a preferred embodiment of the invention radiological examination apparatus comprises a plurality of U-shaped supports which each carry a radiation means on their distal ends; a common axis of rotation for each of said U-shaped supports, said common axis of rotation being alignable with said subject during examination; said U-shaped supports being arcuately rotatable with respect to each other about said common axis of rotation; said radiation means being movable radially with respect to said common axis of rotation; and adjustment means to facilitate radial motion of said radiation means with respect to one another.

Apparatus constructed in accordance with the invention may have a plurality of radiological generators and radiological receptors which are circumferentially and radially movable with respect to a subject being examined to provide simultaneous or sequential examination of the subject at two planes from a plurality of angles to minimize the dangers to the subject by minimizing the quantity of contrast mediums or radioisotopes necessary in the subject.

The apparatus preferably has two generally Ushaped supports, each pivotable about a common axis at a radiological isocenter. The distal ends of the arms of the supports have a radiological source or generator and receptor thereon, respectively. A table for supporting a patient or some other subject is positioned to permit the subject to be aligned with the isocenter. The table is itself conveniently rotatable about an axis normal to the common axis of rotation of the supports and this permits the subject to be examined from all angles inwardly of a sphere centred on the isocenter. Each radiological generator and receptor, while being movable circumferentially about the subject, is movable radially towards or away from the subject to provide different intensity of examination as well as simultaneous multiangular examination of the subject.Adjustment means using cables, counterweights and pulleys within the support can permit the radially directed movement of the respective units, while each U-shaped support can be pivotally mounted on a journal which is supported on a heavy base. The support arms move circumferentially with respectto one another and to the subject being examined, the subject being in alignment with the axis of rotation of those arms.

Moreover, the arms are lockable relative to each other but movable circumferentially about the axis of rotation so that a series of biplanar views can be provided around an isocenter.

The invention may be understood more readily, and various other aspects and features of the invention may become apparent, from consideration of the following description.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, wherein: Figure 1 is a side elevational view of a radiological examination apparatus constructed in accordance with the present invention, portions being deleted for clarity; Figure2 is a view taken along the lines Il-Il of Figure 1; Figure 3 is a plan view of the radiological apparatus, with portions of the apparatus again deleted for clarity; and Figure 4 is a side elevational view of the support member.

Referring now to the drawings in detail, and particularly to Figure 1,there is shown a radiological examination apparatus 10 comprising a first Ushaped support 12 and a second U-shaped support 14, pivotally mounted with respect to one another on a common shaft 16, which itself may be rotationally movable in a collar 18 which is fixedly supported on a heavy base 20. The first and second supports 12 and 14 pivot about a common axis "A" which is the axis of the common shaft 16. The axis "A" is in alignment with that portion of a patient "P" or subject being examined, shown in Figure 1 on a radiation transparent table "T".The common axis "A" may be generally horizontally disposed or it may be vertically arranged about the table "T" and the subject being examined; The first support 12 comprises a pair of hollow generally parallel extended arms or members 22 and 24 connected by a hollow transverse member 26.

Each extended arm or member 22 and 24 has a frame 28 at its distal end thereof. On one extended arm 24 the frame 28 thereon movable secures a radiation means, such as a radiation image receptor 30, and the frame 28 on the other extended arm 22 secures a radiation means such as a radiation source 32. The radiation image receptor 30 and the radiation source 32 may move radially with respect to the common axis "A", in conjunction with one another to vary the imagery of the radiological examination.

The second support 14 is arranged in a manner similar to the first support 12, except that it has a pair of generally parallel extending arms or members 34 and 36, which may not be as long as the extended arms or members 22 and 24 of the first support 12 because of their overlapping relationship. The extended arms 34 and 36 (only one being shown in Figure 1 for clarity) are interconnected by a hollow transverse member 38. Each extended arm 34 and 36 of the second support 14 has a frame 28 at the distal end thereof. On one of the extending arms 34, the frame 28 movably secures a radiation means, such as a radiation image receptor 30 and the frame 28 on the other extended member 36 movably secures a radiation means, such as a radiation source 32 shown more clearly in Figures 2 and 3.

Each set of radiation sources and receptors 30, 32 has a radiation axis intersecting the rotational axis "A" at a common isocenter "C" (Figure 3) inside the patient or subject for examination "P". Furthermore, the table "T" is rotatable about the isocenter "C".

The rotation of the table "T" and of the two U-shaped supports 12,14 allows radiological examination from all angles inwardly of an imaginary sphere with its center at the isocenter "C".

Each extended arm 22, 24, 34 and 36 is hollow, as is each transverse member 26 and 38, in which hollow space is disposed adjustment means in the form of a system 40 of cables, pulley and counterweights to facilitate the radially directed movement of the radiation sources 32 and the radiation image receptors 30. A portion of the system 40, is shown in Figure 4, in one of the extended arms 22, wherein a double pulley 42 having two sheaves is disposed in the distal end thereof, near the radiation source 32.

Another arrangement of pulleys 44 and 46 is disposed at the elbow or juncture of the interconnecting member 26 and the extended arm 22, and a further double pulley 48 having double sheaves is disposed at an intermediate location in the interconnecting member 26. A flexible cable 50 is attached at one end to an arm 52 which slides on a rod 56 provided on the radially outwardly directed side of the frame 28 on the extended arm 22. Limit stops 57 are disposed at the outer ends of the rod 56. The cable 50 wraps partially around the radially-inward portion on one of the sheaves on the double pulley 42 and is carried through the hollow portion of the extended arm 22 to wrap around the radially outer side of one of the pulleys 46 at the elbow of the support 12, and continues radially inwardly in the transverse member 26 to wrap around a sheave of the further double pulley 48 therein, thence radially outwardly to a weight "W" of proper balancing characteristics, and continues from the radially outer end thereof around another pulley 44 at the elbow of the support 12, out through the extended arm 22 and around the other sheave of the double pulley 42 and thence radially inwardly to be secured on an arm 54 on the radially inwardly directed side of the frame 28 on the extended arm 22.The frames 28 which support the source 32 and the receptor 30 are slidable on the rods 56 on each extended arm 22, 24. An endless cable 58 is disposed in a figure eight configuration between the second sheave on the double pulley 48 at the intermediate position in the connecting member 20, and a sheave on another double pulley 48' spaced towards the other extended arm 24 and which comprises the remaining portion of the functional system 40 in the first support 12. The double pulleys 48 and 48' have their respective sheaves fixedly attached to one another to facilitate selective effectuation of simultaneous radially inwardly and radially outwardly directed movement of the support arms ' respective radiation image receptor 30 and the radiation source 32.If desired a single loop can be substituted for the "8" configuration to allow simultaneous movement of the receptor 30 and source 32 in the same direction.

The pulley system in the second support 14 is similar to that described in the first support 12 and the image intensity may be varied according to the particular radial separation of the radiation means.

The radiation emitting means on each support 12 and 14 are preferably actuated seriatim to eliminate chance interference between intersecting radiation which might otherwise obfuscate the images of the subject on the film plate. A lock 49 is provided on the bearing member 53 which engages bearing member 16 so as to interlock the supports 12 and 14 in fixed angular relationship with each other so as to allow the two supports 12 and 14 to maintain the fixed angular overlapping examination around the common axis "A".

A radiological examination of a patient "P" is facilitated further by his disposition on a table "T", the table itself being movable in any of three directions, two of which are shown by the arrows "M" in Figure 3. Of these two directions, one is rotational about the isocenter "C" and the other allows movement parallel to common axis "A". In Figure 1, the support'S" for the table "T" includes an arcuate leg releasably and lockably supported in a base "B" which is rotatably disposed on a floor stand "F". The radiological apparatus comprises radiation sources and radiation receptors which may be moved inwardly and/or outwardly with respect to the common axis "A", by manual stipulation or by motorization of the counterweight system, while the supports 12 and 14 swing around the common axis "A", as shown by the arrows "R" in Figure 2.

Claims

1. Radiological apparatusforthe examination of a subject; said apparatus comprising supports which each carry radiation means including a radiation source and a radiation receptor; each of said supports being independently rotatable about a common axis of rotation which can be aligned with the subject during examination.

2. Radiological apparatus according to claim 1, wherein each support has support arms and said radiation means are disposed on the distal ends of said support arms, each of said radiation means being movable radially with respect to said common axis of rotation.

3. Radiological apparatus according to claim 2, wherein each of said radiation means is associated with adjustment means to permit selective radial movement with respect to said common axis.

4. Radiological apparatus according to claim 3, wherein said adjustment means comprises cable means fixed at each end to said radiation means, said cable means cooperating with a plurality of spaced pulleys and at least one counterweight to permit simple regulation of the radial distance between said radiation source and radiation receptor.

5. Radiological apparatus according to claim 4, wherein said adjustment means further includes an interconnection arranged between respective radiation source and radiation receptor within the distal ends of each support arm, said interconnection effectuating simultaneous radially directed movement of said radiation source and radiation receptor.

6. Radiological apparatus according to claim 5, wherein said adjustment means are arranged within said support arms.

7. Radiological apparatus according to any one of claims 1 to 6 wherein said supports are journalled about a single shaft, said shaft being supported in a heavy base mounting.

8. Radiological apparatus according to any one of claims 1 to 7 and further including locking means arranged to lock said supports in a fixed angular relationship with each other while allowing joint motion around said common axis of rotation.

9. Radiological apparatus for the examination of a subject or patient; said apparatus comprising an arrangement of support arms which each carry radiation means including a radiation source and a radiation receptor; a common axis of rotation for each of said support arms, said axis of rotation in alignment with said subject being examined; said support arms being rotatable with respect to each other, about said axis of rotation.

10. Radiological apparatus for the examination of a subject; said apparatus comprising: a plurality of U-shaped supports which carry a radiation means on their distal ends; a common axis of rotation for each of said U- shaped supports, said common axis of rotation being alignable with said subject during examination; said U-shaped supports being arcuately rotatable with respect to each other about said common axis of rotation; said radiation means being movable radially with respect to said common axis of rotation; and adjustment means to facilitate radial motion of said radiation means with respect to one another.

11. Radiological apparatus according to claim 10, wherein said adjustment means comprises a plurality of pulleys and a weighted cable means.

12. Radiological apparatus according to claim 10 or 11 and further including locking means arranged to lock said U-shaped supports together in a fixed angular relationship with each other while allowing joint motion around said common axis of rotation.

13. Radiological apparatus according to any one of the preceding claims and further comprising an examining table disposed on a plane parallel to said common axis of rotation, said examining table being rotatable on an axis normal to said axis of rotation whereby biplanar radiological views can be made on planes about said axis normal to said common axis.

14. Radiological apparatus according to claim 13, wherein said examining table is also movable along said common axis.

15. Radiological apparatus according to claim 9, wherein two support arms are movable about the axis of rotation.

16. Radiological apparatus according to claim 15, wherein said two support arms arejournalled about a single shaft, said shaft being supported in a heavy base mounting.

17. Radiological apparatus according to claim 9, 15 or 16 further including locking means arranged to lock said arrangement of support arms in a fixed angular relationship with each other while allowing joint motion around said common axis of rotation.

18. Radiological examination apparatus comprising a base, first and second supports mounted on the base to rotate independently about a common axis, each support having two arms extending parallel to said common axis, a radiation source and a radiation receptor mounted at the respective ends of the arms of each support, the radiation sources and receptors having a radiation axis which intersect at a common isocenter on the common axis of rotation.

19. Radiological apparatus according to claim 18, and further comprising a table for supporting a subject under examination, the table being rotatable about an axis normal to the rotational axis of the supports passing through the isocenter, whereby the subject can be examined from all angles inwardly of a sphere centered on the isocenter.

20. Apparatus according to claim 9, wherein the radiation sources and receptors have radiation axes which intersect the common rotational axis at a common isocenter and there is further provided an examining table mounted relative to the support arms to rotate on an axis normal to the common rotational axis and passing through the isocenter so that a subject or patient on the table can be examined from all angles inwardly of a sphere centered on the isocenter.

21. Radiological examination apparatus substantially as described with reference to, and as illustrated in, the accompanying drawings.