WO2009096290A1

WO2009096290A1 - Medical diagnostic imaging device and method

Info

Publication number: WO2009096290A1
Application number: PCT/JP2009/050868
Authority: WO
Inventors: Ting Wang
Original assignee: Hitachi Medical Corporation
Priority date: 2008-01-31
Filing date: 2009-01-21
Publication date: 2009-08-06
Also published as: JPWO2009096290A1; JP5468909B2

Abstract

A medical diagnostic imaging device comprising an imaging means for imaging plural three-dimensional volume data on a desired site of a subject with the movement of the desired site of the subject in a photographing space, a storage means for storing the plural three-dimensional volume data acquired by the imaging means, an input means for inputting the position of a desired cross section in the desired site of the subject, and an image generating means for generating the image of the desired cross section from the three-dimensional volume data stored in the storage means, comprises a detection means for detecting positional information on the desired site of the subject. The image generating means generates each image of the desired cross section from each of the plural three-dimensional volume data on the desired cross section by using the positional information detected by the detection means.

Description

Medical image diagnostic apparatus and method

The present invention relates to a medical image diagnostic apparatus and method capable of observing a change in a desired part of a subject that occurs with the movement of the subject.

In a medical image diagnostic apparatus such as a magnetic resonance imaging apparatus (hereinafter referred to as an MRI apparatus) or an X-ray CT apparatus, a tomographic image of a desired position of a subject is imaged, or a desired part of a subject is three-dimensionally imaged. Or taking pictures.

In recent years, research has been conducted on “dynamic imaging” in which X-ray fluoroscopy is used while moving joints when diagnosing damage to movable parts such as knees and elbow joints and spines. (For example, refer to Patent Document 1 regarding a dynamic imaging system and a dynamic imaging method.) Because, for diagnosis of movable parts such as knees and elbow joints and spines, the joints and spines are not stationary. This is because diagnosing how the joint, spine, and the like change with its movement is important in diagnosing defects (lesions) of the joint, spine, and the like.

On the other hand, Patent Document 2 discloses a technique for automatically detecting a tomographic plane at a desired position by detecting the movement of a subject using a magnetic resonance imaging apparatus.

JP 2006-149488 A JP 11-318849 A

However, Patent Document 1 discloses a technique for driving the joint, spine, and the like of the subject, but the desired cross-sectional position when performing dynamic imaging with an MRI apparatus or the like depends on the movement of the subject. No technology is disclosed for detecting how it is changing.

Patent Document 2 discloses a technique for displaying a desired cross section by quantitatively detecting the movement of the neck of the subject by rotating the head support. In this technology, the part to be imaged was a rigid body such as the head, so it was possible to detect the movement of the entire head only by turning the head support part. In such a case where the soft part is targeted, it is considered that the diagnostic part moves more complicatedly. In such a case, it is insufficient in accuracy to estimate the movement of the subject using only the fulcrum.

The present invention provides a medical image diagnostic apparatus capable of accurately detecting movement of a desired part of a subject, performing dynamic imaging, and displaying a desired cross section corresponding to the movement of the desired part. With the goal.

The invention for achieving the above-described object includes an imaging means for imaging a plurality of three-dimensional volume data for a desired part of the subject along with movement of the desired part of the subject in the imaging space, and the imaging Storage means for storing a plurality of three-dimensional volume data obtained by the means, input means for inputting a position of a desired cross section within a desired region of the subject, and an image of the desired cross section stored in the storage means In the medical image diagnostic apparatus provided with the image generation means for generating the generated three-dimensional volume data, the medical image diagnosis apparatus further comprises detection means for detecting position information of a desired part of the subject, and the image generation means is controlled by the detection means. Using the detected position information, an image of the desired cross section is generated from each of the plurality of three-dimensional volume data of the desired cross section.

Also,
(1) a step of imaging a plurality of three-dimensional volume data of the subject with movement of a desired part of the subject in the imaging space;
(2) generating a reference screen from the three-dimensional volume data imaged in the step (1);
(3) a step of inputting a desired cross-sectional position for image generation on the reference screen generated by the step (2);
(4) A medical image diagnostic method comprising a step of generating an image of a desired cross-sectional position input in the step (3),
(5) a step of selecting any one or more three-dimensional volume data from a plurality of three-dimensional volume data obtained in the step (1),
The step (2) generates a reference screen for the three-dimensional volume data selected in the step (5),
(6) detecting a change in position of a desired part of the subject for each of the plurality of three-dimensional volume data;
(7) Based on the position change of the desired part detected by the step (6), comprising the step of calculating the desired cross-sectional position in other three-dimensional volume data,
In the step (4), an image of a desired cross-sectional position which is input in the step (3) and whose position change is detected in the step (7) is generated.

According to the present invention, a medical image diagnostic apparatus and method capable of accurately detecting movement of a desired part of a subject to perform dynamic imaging and displaying a desired cross section corresponding to the movement of the desired part. Can provide.

1 is a block diagram showing the overall configuration of an MRI apparatus that is an example of a medical image diagnostic apparatus to which the present invention is applied. The figure which shows the three-dimensional gradient echo type | mold multi-shot echo planar method with which the MRI apparatus of this invention is provided. The figure explaining dynamic imaging | photography. (a) The figure which shows a mode that the desired several cross section which consists of multi slices was set on the 1st volume data. (b) The figure which shows the desired several cross section which should be set after the angle which bends a knee etc. changes. The figure which shows the internal structure for performing dynamic imaging of the MRI apparatus in a present Example. The figure which shows the flow of dynamic imaging | photography in a present Example. Screen displayed by the display process.

Explanation of symbols

V1 desired multiple sections, V2 desired multiple sections after the angle of bending the knee etc. is changed

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 is a block diagram showing an overall configuration of an MRI apparatus which is an example of a medical image diagnostic apparatus to which the present invention is applied. As shown in FIG. 1, this MRI apparatus mainly includes a static magnetic field generation system 1, a gradient magnetic field generation system 2, a transmission system 3, a reception system 4, a signal processing system 5, a control system (sequencer 6 and CPU7).

The static magnetic field generation system 1 generates a uniform static magnetic field in a space (imaging space) around the subject 8, and is composed of a magnet device of a permanent magnet system, a normal conduction system, or a superconductivity system.

Gradient magnetic field generation system 2 includes, for example, three gradient magnetic field coils 9 that generate gradient magnetic field pulses in these three axial directions when the direction of the static magnetic field is the Z direction and the two directions orthogonal thereto are X and Y, and Are each composed of a gradient magnetic field power source 10 for driving each of. By driving the gradient magnetic field power supply 10, gradient magnetic field pulses can be generated in the three axes of X, Y, and Z or in the direction in which these are combined. The gradient magnetic field pulse is applied to give position information to the NMR signal generated from the subject 8.

The transmission system 3 includes a high frequency oscillator 11, a modulator 12, a high frequency amplifier 13, and a high frequency irradiation coil 14 for transmission. The RF pulse generated by the high-frequency oscillator 11 is modulated into a signal having a predetermined envelope by the modulator 12, amplified by the high-frequency amplifier 13, and applied to the high-frequency irradiation coil 14, whereby the nucleus of the atom constituting the subject is An electromagnetic wave (high frequency signal, RF pulse) that causes magnetic resonance is irradiated to the subject. The high-frequency irradiation coil 14 is usually disposed in the vicinity of the subject.

The reception system 4 includes a high-frequency reception coil 15 for reception, an amplifier 16, a quadrature detector 17, and an A / D converter 18. The NMR signal generated by the subject as a response to the RF pulse irradiated from the high-frequency irradiation coil 14 for transmission is detected by the high-frequency reception coil 15 for reception and amplified by the amplifier 16, and then the quadrature detector 17 Then, it is converted into a digital quantity by the A / D converter 18 and sent to the signal processing system 5 as two series of collected data.

The signal processing system 5 includes a CPU 7, a storage device 19, and an operation unit 20. The CPU 7 performs various signal processing such as Fourier transform, correction coefficient calculation, and image reconstruction on the digital signal received by the reception system 4. . The storage device 19 includes a ROM 21, a RAM 22, a magneto-optical disk 23, a magnetic disk 24, and the like.For example, a program for performing image analysis processing and measurement over time and an invariant parameter used in the execution are stored in the ROM 21 for all measurements. The obtained measurement parameters and echo signals detected by the reception system are stored in the RAM 22 and the reconstructed image data is stored in the magneto-optical disk 23 and the magnetic disk 24, respectively. The operation unit 20 includes input means such as a trackball or a mouse 25 and a keyboard 26, and a display 27 for displaying a GUI necessary for input and displaying processing results in the signal processing system 5. Information necessary for various processes and control performed by the CPU 7 is input via the operation unit 20. An image obtained by photographing is displayed on the display 27.

The control system consists of a sequencer 6 and a CPU 7, and controls the operations of the gradient magnetic field generation system 2, the transmission system 3, the reception system 4 and the signal processing system 5 described above. In particular, the gradient magnetic field pulse and RF pulse application timing generated by the gradient magnetic field generation system 2 and the transmission system 3 and the echo signal acquisition timing by the reception system 4 are controlled by the sequencer 6 based on a predetermined pulse sequence determined by the imaging method. .

Next, a three-dimensional gradient echo type multi-shot echo planar method provided in the MRI apparatus of the present invention will be described with reference to FIG. In FIG. 2, Gs, Gp, and Gr represent slice selective gradient magnetic field, phase encode gradient magnetic field, and frequency encode gradient magnetic field axes, respectively, and RF, AD, and Echo represent RF pulse, sampling window, and echo signal, respectively. 201 is an RF pulse, 202 is a slice selective gradient magnetic field pulse, 203 is a slice encode gradient magnetic field pulse, 204 is a phase encode gradient magnetic field pulse, 205 is a phase blip gradient magnetic field pulse group, 206 is a frequency phase gradient magnetic field pulse, 207 Is a frequency encoding gradient magnetic field pulse group, 208 is a sampling window group, and 209 is an echo signal group.

In the echo planar method, the sequencer 4 measures the echo signal 209 for each readout gradient magnetic field pulse 207 while changing the polarity of the readout gradient magnetic field pulse 207 for each irradiation of the RF pulse 201. This is repeatedly executed at a time interval 210 (repetition time TR), and the number of echo signals necessary for image reconstruction is measured. The number of echo signals necessary for image reconstruction is generally about 64, 128, or 256 depending on the matrix of the image to be created. The number after-(underscore) represents a repetition number. FIG. 2 shows the first first sequence among a plurality of repetitions, and the second and subsequent repetition sequences are the same as the first one, and are omitted.

As described above, in the echo planar method, a plurality of echo signals are measured by one RF pulse, so that an image can be acquired at a higher speed than a sequence in which one echo signal is measured by one RF pulse. In the case of FIG. 2, since six echo signals 209 are measured by one RF pulse 201, it can be photographed six times faster.

Example 1
Next, Example 1 of the present invention will be described. In Embodiment 1 of the present invention, three-dimensional imaging is performed using the MRI apparatus configured as shown in FIG. 1 and using the imaging sequence shown in FIG.

In the three-dimensional imaging in the present embodiment, for example, three axes (X axis, Y axis, Z axis) in the orthogonal coordinate system are defined in the imaging space (FOV) of the MRI apparatus. Further, any one of the three axis directions is taken as one of the slice encoding direction, the phase encoding direction, and the frequency encoding direction in the sequence diagram of FIG. 2, and the volume data is continuously collected. The obtained three-dimensional volume data is sequentially stored in the storage device 19.

The dynamic imaging that is the subject of the present invention is, for example, within the imaging area (FOV) defined in the imaging space of the MRI apparatus, the subject moves his / her foot, knee, etc. as shown in FIG. The doctor (operator) etc. diagnoses how the joints such as these change. For example, while the subject changes the angle of the foot (or the angle at which the knee is bent) from a predetermined position (point A) to another position (point B), 100 pieces of 3D volume data are obtained in time series using the MRI device. Then, for each volume data, an image of the imaging section to be diagnosed is reconstructed and displayed, and the change is observed.

For example, if you want to diagnose the joints of the foot, change the angle at which the subject bends the knee in various ways, and use the volume data obtained at each angle to determine the cross section from the knee to the foot and the toes of the foot. A desired cross-sectional image, such as a cross section from the heel to the heel, is cut out and displayed in time series, and the doctor or the operator changes the desired cross section (cross section from the knee position to the foot direction or from the toe of the foot to the heel) over time. Observe.

However, in such dynamic imaging, the angle at which the knee is bent changes sequentially, so the position of the desired cross-section (cross-section from the knee position to the foot direction or from the foot toe to the heel) is within the 3D volume data. It changes sequentially. Conventionally, three screens of sagittal, coronal, and axial (XY plane, YZ plane, and ZX plane for the three axes) are displayed on the display 27 of the MRI apparatus based on the three-dimensional volume data. A line segment representing a cross-sectional position is sequentially input (for each volume data), and a cross-section to be sequentially observed needs to be displayed for each three-dimensional volume data.

The MRI apparatus according to the first embodiment of the present invention includes a detection unit that detects a movement of a portion to be diagnosed by a subject, and sets an observation target corresponding to the movement of the target portion detected by the detection unit. The cross section can be reconstructed and displayed. Details will be described below.

First, coordinate transformation that is the basis of image reconstruction in this embodiment will be described. More specifically, the coordinate conversion processing here is used by the MRI apparatus to calculate the position of the observation target cross section to be subjected to image reconstruction in correspondence with the movement of the target portion detected by the detection means. It is coordinate transformation.

FIG. 4 schematically shows coordinate transformation in the present invention. However, the coordinate transformation described in FIG. 4 is the first piece of volume data obtained in time series of 100, and after the doctor or the operator inputs which cross-sectional position is the object of diagnosis, MRI The apparatus is used to calculate how the position of the inputted diagnosis target section changes in time series according to the movement (rotation angle or the like) of the diagnosis target part detected by the detection means.

For example, FIG. 4 (a) shows a state in which a desired plurality of cross-sections composed of multi-slices are set on the first volume data. In FIG. 4A, for example, an operator or a doctor inputs and defines a plurality of slices V1 as a desired plurality of cross sections in the volume data.

V1 consists of a plurality of desired cross sections C1 ₁ to C1 _n . Next, in this embodiment, when the angle at which the knee or the like is bent changes with time, the position of the observation site of the subject changes in the volume data, so that a plurality of desired cross sections (V1: C1 ₁ to C1 _n ). The position of must also be changed.

FIG. 4 (b) illustrates a desired plurality of sections to be set after the angle at which the knee or the like is bent changes, and setting of the desired plurality of sections according to a change in the angle at which the knee or the like is bent. The position (V1: C1 ₁ to C1 _n ) has been changed to (V2: C2 ₁ to C2 _n ). Here, the change of a plurality of desired cross-sections (V1: C1 ₁ to C1 _n ) to (V2: C2 ₁ to C2 _n ) is, for example, the rotation matrix R12 when the change in the angle of bending the knee or the like is α. Use C2 = R12 ・ C1 Formula (1)
Can be expressed by a determinant. However, C1 and C2 in the equation (1) define the positions or directions of a plurality of desired cross sections, and are composed of position vectors, direction vectors, or the like. Hereinafter, a detailed example of Expression (1) will be described.

Example 1: Example of rotating coordinate conversion (when rotating around X axis)
When the rotation of the desired part of the subject is performed with the X axis as the rotation axis, the rotation matrix in Equation (1) is expressed as follows.

In Expression (2), α represents a rotation angle for bending the knee or the like. However, the angle α can be obtained, for example, based on how the position coordinates of the marker have changed compared to before rotation, as will be described later. For example, if the position coordinate of the marker A changes to (xa ', ya', za ') after rotation with (xa, ya, za) before rotation, the following equations (3) and (4) The angle α can be obtained by using the equation.

ya '= ya · cosα + za · sinα Equation (3)
za '= -ya ・ cosα + za ・ sinα Equation (4)
Example 2: Example of rotating coordinate transformation (when rotating around Y axis)
When the rotation of the desired part of the subject is performed with the X axis as the rotation axis, the rotation matrix in Equation (1) is expressed as follows.

However, the angle α can determine how the position coordinates of the marker change compared to before rotation as described later, for example. For example, if the position coordinate of the marker A changes to (xa ', ya', za ') after rotation with (xa, ya, za) before rotation, the following equations (6) and (7) The angle α can be obtained by using the equation.

xa '= xa ・ cosα-za ・ sinα Equation (6)
za '= xa ・ sinα ＋ za ・ sinα Equation (7)
Example 3: Example of rotating coordinate transformation (when rotating around Z axis)
When the rotation of the desired part of the subject uses the Z axis as the rotation axis, the rotation matrix in equation (1) is expressed as follows.

However, the angle α can determine how the position coordinates of the marker change compared to before rotation as described later, for example. For example, if the position coordinate of the marker A changes to (xa ', ya', za ') after rotation with (xa, ya, za) before rotation, the following equations (9) and (10) The angle α can be obtained by using the equation.
xa '= xa ・ cosα-ya ・ sinα Equation (9)
ya '= xa · sinα + ya · sinα Equation (10)

Example 4: Example of rotating coordinate conversion (when none of the X, Y, or Z axes is rotated)
As in Example 1 to Example 3 described above, when any of the X, Y, and Z axes is not a rotation axis and the λ and φ angles are moved from the angles of λ and φ to λ + Δλ, φ + Δφ in the polar coordinate system, The rotation matrix is expressed as follows.

Formula (11)
However, in this example, since there are a plurality of parameters related to the rotation angle, it is necessary to obtain each parameter based on the change in the position coordinates of the plurality of markers.

Next, the internal configuration for performing dynamic imaging of the MRI apparatus in this embodiment will be described with reference to FIG.

51 is a data storage unit that corresponds to the ROM 21, RAM 22, magneto-optical disk 23, magnetic disk 24, etc. in FIG. 1, and stores echo signals collected by the above-described three-dimensional imaging.

Next, 52 is an MPR processing unit that is connected to the data storage unit 51 and performs arbitrary multi-section reconstruction processing (MPR) that is image reconstruction according to the present embodiment. Arbitrary multi-section reconstruction processing refers to processing for creating a reconstruction image of a cross section at an arbitrary position from a plurality of two-dimensional images. For example, in the description of FIG. 4, a plurality of cross sections (C2 ₁ to C2 _N, etc.) at a desired position (for example, the position of the cross section from the toe of the foot to the heel) are reconstructed from volume data composed of a plurality of two-dimensional images. Process.

Next, a display processing unit 53 is connected to the MPR processing unit 52 and performs processing for displaying the MPR-processed image on an image display unit 54 described later.

Next, reference numeral 54 denotes an image display unit connected to the display processing unit 53 for displaying the MPR processed image. For example, the display 27 in FIG. 1 is connected to the display processing unit 53 and is used as the image display unit 54 to display an MPR-processed image.

Next, reference numeral 55 denotes an operation unit that is connected to the MPR processing unit 52, the display processing unit 53, and the image display unit 54, and operates the MPR processing unit 52, the display processing unit 53, and the image display unit 54. The trackball or mouse 25 and the keyboard 26 in FIG. 1 are used as an operation unit 55 for scanning the MPR processing unit, the signal processing unit, and the display processing unit.

Next, the flow of dynamic shooting in this embodiment will be described with reference to FIG. Hereinafter, each step of the flowchart of FIG. 6 will be described in order.

(Step 1) Implementation of dynamic imaging The doctor or operator places the subject in the MRI apparatus and performs dynamic imaging to acquire multiple 3D volume data in time series using the MRI apparatus. The three-dimensional volume data is input to the data storage unit 51. However, in dynamic imaging in this step, feet etc. in the imaging area (FOV) formed along the three axes (X axis, Y axis, Z axis) in the Cartesian coordinate system set in the imaging space of the MRI apparatus Move while moving.

(Step 2) Creation and display of MPR reference input screen One of a plurality of three-dimensional volume data obtained in time series by the MRI apparatus is taken out, and an MPR reference plane input screen is created and displayed. The MPR reference plane input screen is a screen for inputting a desired cross section in the MPR processing, for example, an image of a sagittal, coronal, or axial cross section.

(Step 3) Setting the desired section for MPR processing On the MPR reference plane input screen displayed in Step 2 (for example, one of sagittal, coronal, or axial section), the doctor or surgeon performs MPR processing. Parameters and the like are input in order to set a desired cross section (hereinafter referred to as cut plane). Details of the input screen will be described later. For example, a doctor or an operator inputs a plurality of parallel curves or straight lines, or sets a line segment in a radial shape around an axis perpendicular to one screen. For example, when the cut plane is designated by multi-slice, the thickness of the cut plane configuring each multi-slice, the region of interest on the cut plane, the interval between the cut planes, the number of cut planes, and the like are set. Specifically, for setting a plurality of parallel curves or straight lines, a single central line is set, an interval between cut planes and the number of cut planes are input, and a plurality of cut planes are set. Further, when setting a line segment in a radial shape, a desired cross section to be subjected to the MPR process may be set according to the center point position, the angle interval, or the number of lines.

(Step 4) Marker position designation In a step described later, a doctor or an operator designates a marker serving as a reference for detecting the rotation angle of the diagnosis target portion of the subject. The detection of the rotation angle of the diagnosis target part of the subject is performed automatically from the image by, for example, (a) known tissue tracking technology, (b) placing a jig that generates a large NMR signal at the diagnosis part of the subject. Alternatively, a method of manually detecting the jig, (c) a method of using an optical system as described in International Publication No. WO03 / 026505A1, and the like are conceivable. The marker position designation in this step is changed according to the detection method of the rotation angle of the diagnosis target region of the subject.

For example, when using a method that automatically or manually detects from the image by placing a jig that generates a large NMR signal at the diagnostic site of the subject, place a marker on the part of the foot and display the image The pixel intensity and size above are input and stored in the MRI apparatus, and can be recognized from the two-dimensional image data in each volume data by pattern matching from the image. In addition, when detecting the rotation angle of a subject using a known tissue tracking technique, an image of a predetermined organ pattern (for example, an image of a part of a foot (ROI)) is displayed on the screen displayed in step 2. Allow input. When using an optical system as described in International Publication No. WO03 / 026505A1, for example, a light emitter and a reflector are arranged in the gantry of the MRI apparatus or in a part of the subject.

Also, the number of markers set in this step varies depending on the degree of freedom of rotation of the diagnosis target part of the subject. For example, when rotating the foot, the knee or the like is fixed to some jig and the tip is rotated beyond the knee, the rotation axis is any of the above-mentioned X axis, Y axis, and Z axis, and the rotation center is the knee If it is fixed by a single, etc., the movement of the object to be diagnosed (beyond the knee) is uniquely determined by the position of one marker placed on the foot side from the knee, so the number of markers is only one Good. In addition, when the rotation axis is not one of the above-mentioned X axis, Y axis, and Z axis, the movement of the subject to be diagnosed (beyond the knee) is not uniquely determined, as in Example 4 above. Since it is possible to rotate, it is considered that two or more markers are required. In addition, if the foot not only rotates around the knee but also the ankle, the diagnostic site of the subject near the ankle is thought to move in a complex manner. In that case, the number of markers is three. This is considered necessary.

(Step 5) For each of the volume data, the position of the marker and the angle detection of the diagnosis target part For each of the volume data other than the volume data specified in Step 2, the position of the marker specified in (Step 4) is sequentially described above (a) The detection angle is detected according to each of the methods (c) to (c), and the rotation angle of the diagnosis target part of the subject is detected for each volume data by the method according to Examples 1 to 4.

(Step 6) Calculate the position of the desired cross-section for each volume data According to the rotation angle detected in Step 5, as shown in FIG. 4, the position of the desired cross-section set in Step 3 is set for each volume. Calculate for each piece of data. In calculating the change in the position of the desired cross section, the determinants as shown in Examples 1 to 4 above are used. However, if the movement of the subject to be diagnosed is not only rotational movement but also parallel movement, the amount of parallel movement is detected by detecting the position of the marker for each volume data in (Step 5). It is considered that a known translational transformation may be added to the rotational coordinate transformation by the determinant as shown in 1 to 4. For example, equation (1) may be transformed into equation (12) so that an offset term representing translation is added.

C2 ＝ R12 ・ C1 ＋ P12 (12)
P12 in the equation (12) is a vector for adding an offset term to each component of C1 made up of a position vector or a direction vector.

(Step 7) Generating a cross-sectional image by interpolation processing The MRI apparatus sets one of a plurality of three-dimensional volume data in Step 3, and in Step 6 for each position of the desired cross section obtained for each volume data. A cross-sectional image is obtained by interpolation processing. More specifically, the MRI apparatus has a data arrangement of three-dimensional volume data composed of a plurality of two-dimensional data when the desired cross-sectional arrangement direction is oblique to the X, Y, and Z3 axes. In some cases, the position and the position of each pixel of the desired cross-section to be reconstructed do not necessarily match. In such a case, the pixel value of the location where the position does not necessarily match is obtained by interpolation.

(Step 8) Display Processing The display processing unit 53 performs display processing for displaying the reconstructed image of each desired cross section obtained in Step 7 on the image display unit 54. The screen displayed by this step is as shown in FIG. Hereinafter, the display screen of FIG. 6 will be described. In FIG. 7, reference numeral 71 denotes four screens displayed on the image display unit. The upper right of the four screens is the sagittal direction screen, the upper left is the coronal direction screen, the lower left is the axial direction screen, and the lower right is by the MPR process. The obtained tomogram is shown.

Next, 72 is a scroll bar for switching the display of a plurality of three-dimensional volume images obtained in time series in step 1. For example, when the scroll bar is located at the left end, it shows the volume data obtained at the first timing in time series, and the display screen switches to a new one in time series as the scroll bar is moved to the right. It shows that. Reference numeral 73 denotes a volume data number. For example, when the volume data number is 1 to 100, the number 1 is the earliest number in time series, and the number 100 is the earliest time series number. 74 is for designating the rotation angle of a part to be diagnosed such as a foot in each volume data. By designating the rotation angle, the CPU 7 selects and displays volume data when the diagnosis target part is at the designated angle.

75 is a scroll bar for selecting which volume data to display by switching the display cross section to the lower right screen of 71 for each volume data. More specifically, in Step 3, it is possible to specify a case where there are a plurality of desired cross sections. In that case, a plurality of desired cross sections can be displayed by moving the scroll bar on the display cross section on the lower right screen. It can be switched sequentially. 76 is for a doctor or an operator to input information regarding a desired cross section to be subjected to MPR processing in Step 3. For example, parameters such as the thickness of the cut plane, the region of interest on the cut plane, the interval between the cut planes, and the number of cut planes as described in step 3 are input.

77 is for setting a cross-section sharing range, and the position of a desired cross-section is shared by the entire three-dimensional volume data range (for example, up to 1 to 100) or the first half (for example, 1 to 50). It is shown whether it is a part of it and is part of it, or it is shared and part of it in the latter half (for example 51 to 100).

78 indicates the relationship between the volume data number and the angle of the diagnosis target part of the subject for a plurality of three-dimensional volume data. For example, the table shows that the angle of the diagnosis target part of the subject increases as the volume data number increases and the time advances in time series.

As described above, according to this embodiment, only one MPR processing parameter setting (setting of a desired cross section) is performed for one piece of three-dimensional volume data, and the movement of a desired part of the subject can be handled. Thus, it is possible to display a desired cross-sectional image for other three-dimensional volume data. That is, an imaging unit that captures a plurality of three-dimensional volume data for a desired part of the subject together with a movement of the desired part of the subject in the imaging space, and a plurality of three-dimensional data obtained by the imaging unit Storage means for storing volume data, input means for inputting a position of a desired cross section within a desired region of the subject, and an image of the desired cross section are generated from three-dimensional volume data stored in the storage means In the medical image diagnostic apparatus provided with the image generation means, the image generation means includes detection means for detecting position information of a desired part of the subject, and the image generation means uses the position information detected by the detection means, An image of the desired section is generated from each of the plurality of three-dimensional volume data of the desired section.

Further, the detecting means detects position information of a specific position of the desired part, and when the desired part moves around a fixed fulcrum part, the specific position is provided in one place. The movement of the desired part of the subject rotates around the X axis, the Y axis, or the Z axis in the orthogonal coordinate system set in the imaging space of the medical image diagnostic apparatus. . Further, when the movement of the desired part of the subject includes a rotational motion around two rotational axes in the polar coordinate system, the number of the specific positions is set to two or more, and the detection means is the 2 The position of the desired part is detected by detecting more than one specific position.

And a selection unit that selects any one or more of the three-dimensional volume data obtained in time series, and the input unit outputs the two-dimensional data obtained from the three-dimensional volume data selected by the selection unit. A position of a predetermined cross-section is input on a three-dimensional image, and the other three-dimensional volume data not selected by the selection means is selected based on the position information of the desired part detected by the detection means. A calculation means for calculating the position is provided. There may be a case where there are a plurality of desired cross sections, and the case where the desired cross section is a plane or a curved surface is included.

Further, according to the present embodiment, the steps (1) and (2) the steps (1) for imaging a plurality of three-dimensional volume data of the subject with movement of a desired part of the subject in the imaging space ) From the three-dimensional volume data imaged in (2), generating a reference screen (2), and inputting a desired cross-sectional position for image generation on the reference screen generated in the step (2) ( 3) and a medical image diagnostic method comprising a step (4) of generating an image of a desired cross-sectional position input in the step (3), wherein a plurality of three-dimensional images obtained by the step (1) From the volume data, comprising the step (5) of selecting any one or more three-dimensional volume data, the step (2) generates a reference screen for the three-dimensional volume data selected in the step (5), Each of the plurality of three-dimensional volume data represents a change in position of a desired part of the subject. A step (6) for detecting the step, and a step (7) for calculating the desired cross-sectional position in the other three-dimensional volume data based on the position change of the desired part detected in the step (6). (4) provides a medical image diagnostic method characterized by generating an image of a desired cross-sectional position which is input in the step (3) and whose position change is detected in the step (7).

Also, a step (1) of imaging a plurality of three-dimensional volume data of the subject with movement of a desired part of the subject in the imaging space, and a plurality of three-dimensional volumes obtained by the step (1) A step (2) for selecting one or more arbitrary three-dimensional volume data from the data, a step (3) for generating a reference screen from the three-dimensional volume data selected in the step (2), and the step (4) inputting a desired cross-sectional position for image generation on the reference screen generated in (3), and detecting a change in position of a desired part of the subject for each of the plurality of three-dimensional volume data In the step (5), the step (6) for calculating the desired cross-sectional position in the other three-dimensional volume data based on the position change of the desired part detected in the step (5), and the step (4) Input or calculated by the above step (6) Medical image diagnosis method characterized by comprising a step (7) for generating an image of the cross-sectional position is provided.

As a result, it becomes easy to obtain the MPR image of the same cut surface from each of the plurality of three-dimensional volume data, and the setting operation of the cut plane parameter becomes easy and the burden on the operator can be reduced.
(Example 2)
Next, Example 2 of the present invention will be described. Example 2 of the present invention is almost the same as Example 1, except for the following points. That is, in the first embodiment, after the three-dimensional volume data is taken in time series in all time phases in step 1, the processing of step 2 and subsequent steps is performed, but in this embodiment, the three-dimensional volume data is collected. In the middle, the processing from step 2 onwards is performed. For example, if there is a total of 1 to 100 3D volume data, the MRI apparatus will start displaying MPR images from step 2 onwards after the dynamic imaging for the 1st to 50th is completed, and the 51st to 100th tertiary At the stage where the original volume data is collected, the MRI apparatus starts to display the MPR image of step 2 and below for the 51st to 100th.

At that time, the setting of the desired cross section to be subjected to the MPR process in step 3 performed for the first volume data and the setting of the desired cross section to be the target of the MPR process in step 3 performed for the 51st volume data are performed. It may be the same position or a different position in the subject of the specimen diagnosis. By doing so, it can be suitably applied when the rotation trajectory of the object to be diagnosed differs between the first half and the second half of a plurality of three-dimensional volume data, or when the rotation fulcrum differs between the first half and the second half. There is an advantage that it can be suitably handled.

In addition, the MPR image obtained by the MPR process is displayed on the display more quickly than in the first embodiment, and there is an advantage that the diagnosis can be performed immediately.
(Example 3)
Next, Example 3 of the present invention will be described. Example 3 of the present invention is substantially the same as Example 1, except for the following points. That is, in Example 1, after setting the three-dimensional volume data in all time phases in step 1, the desired cross-section to be subjected to the MPR process is set only for the first three-dimensional volume data. However, in this embodiment, all time-phase three-dimensional volume data is divided into two or more groups, and MPR processing is performed separately for each group.

For example, for the 1st to 50th groups of 3D volume data, MPR processing is performed by setting a desired cross section to the first 3D volume data, and for the 51st to 100th groups of 3D volume data, 51 MPR processing may be performed by setting a desired section in the three-dimensional volume data of the face. By doing so, it is possible to suitably cope with the case where the rotation trajectory of the object to be diagnosed differs between the first half and the second half of a plurality of three-dimensional volume data, or when the rotation fulcrum differs between the first half and the second half. There is an advantage that it can be suitably handled.

According to the embodiment of the present invention, the MPR processing parameter setting (setting of a desired section) is performed only for one or a plurality of three-dimensional volume data, and a desired section for other three-dimensional volume data is set. Can be displayed in response to the movement of a desired part of the subject. As a result, it becomes easy to acquire the MPR image of the same cut surface from each of the plurality of three-dimensional volume data, and the setting operation of the cut plane parameter becomes easy, and the burden on the operator can be reduced.

It should be noted that the present invention is not limited to the contents disclosed in each of the above embodiments, and can take various forms without departing from the spirit of the present invention. For example, although the MRI apparatus has been described in the above embodiment, a medical image diagnostic apparatus such as an X-ray CT apparatus may be used. In the above embodiment, arbitrary multi-section reconstruction is described in which a desired section in each phase is displayed after dynamic imaging with a medical image diagnostic apparatus. However, a result obtained by dynamic imaging is stored in a storage device in advance and stored. It goes without saying that a system that only reconstructs an arbitrary multi-section can be used. Even in such a system, it is considered that an arbitrary multi-section reconstruction may be performed as described above.

Claims

An imaging means for imaging a plurality of three-dimensional volume data for the desired part of the subject along with movement of the desired part of the subject in the imaging space, and a plurality of three-dimensional volume data obtained by the imaging means An image for generating the image of the desired cross section from the three-dimensional volume data stored in the storage means. In the medical image diagnostic apparatus provided with the generating means,
Detection means for detecting position information of a desired part of the subject is provided, and the image generation means uses each of the plurality of three-dimensional volume data of the desired section using the position information detected by the detection means. A medical image diagnostic apparatus characterized in that each image of the desired cross section is generated.
2. The medical image diagnostic apparatus according to claim 1, wherein the detection unit detects position information of a specific position of the desired part.
When the desired part moves around a fixed fulcrum part, the specific position is provided in one place, and the movement of the desired part of the subject is set in the imaging space of the medical image diagnostic apparatus 3. The medical image diagnostic apparatus according to claim 2, wherein the medical image diagnostic apparatus rotates with an X axis, a Y axis, or a Z axis as a rotation axis in the orthogonal coordinate system.
When the movement of the desired part of the subject includes a rotational movement about two rotational axes in the polar coordinate system, the number of the specific positions is set to two or more, and the detection means is the two or more 3. The medical image diagnostic apparatus according to claim 2, wherein the position of the desired part is detected by detecting a specific position of the medical image.
A selection means for selecting any one or more from the three-dimensional volume data obtained in time series,
The input means inputs a position of a predetermined cross section on a two-dimensional image obtained from the three-dimensional volume data selected by the selection means, and based on position information of the desired part detected by the detection means 2. The medical image diagnostic apparatus according to claim 1, further comprising a calculation unit that calculates the position of the predetermined cross section for other three-dimensional volume data not selected by the selection unit.
2. The medical image diagnostic apparatus according to claim 1, wherein there are a plurality of the desired cross sections.
2. The medical image diagnostic apparatus according to claim 1, wherein the desired cross section is a plane.
2. The medical image diagnostic apparatus according to claim 1, wherein the desired cross section is a curved surface.
2. The medical image diagnostic apparatus according to claim 1, wherein the medical image diagnostic apparatus is an X-ray CT apparatus or an MRI apparatus.
(1) a step of imaging a plurality of three-dimensional volume data of the subject with movement of a desired part of the subject in the imaging space;
(2) generating a reference screen from the three-dimensional volume data imaged in the step (1);
(3) a step of inputting a desired cross-sectional position for image generation on the reference screen generated by the step (2);
(4) A medical image diagnostic method comprising a step of generating an image of a desired cross-sectional position input in the step (3),
(5) a step of selecting any one or more three-dimensional volume data from a plurality of three-dimensional volume data obtained in the step (1),
The step (2) generates a reference screen for the three-dimensional volume data selected in the step (5),
(6) detecting a change in position of a desired part of the subject for each of the plurality of three-dimensional volume data;
(7) Based on the position change of the desired part detected by the step (6), comprising the step of calculating the desired cross-sectional position in other three-dimensional volume data,
The medical image diagnostic method characterized in that the step (4) generates an image of a desired cross-sectional position that is input in the step (3) and whose position change is detected in the step (7).
(1) a step of imaging a plurality of three-dimensional volume data of the subject with movement of a desired part of the subject in the imaging space;
(2) a step of selecting any one or more three-dimensional volume data from a plurality of three-dimensional volume data obtained in the step (1);
(3) a step of generating a reference screen from the three-dimensional volume data selected in the step (2);
(4) a step of inputting a desired cross-sectional position for image generation on the reference screen generated by the step (3);
(5) detecting a change in position of a desired part of the subject for each of the plurality of three-dimensional volume data;
(6) Based on the position change of the desired part detected in the step (5), calculating the desired cross-sectional position in other three-dimensional volume data;
(7) A medical image diagnostic method comprising a step of generating an image of a cross-sectional position input in the step (4) or calculated in the step (6).