Medical image diagnostic device, method of controlling medical image diagnostic device, and program

Abstract

To provide a medical image diagnostic device facilitating generation of a reconstructed image with a subject facing a desired direction without deteriorating image quality.SOLUTION: A medical image diagnostic device includes an imaging unit, a control unit, and a reconstruction unit. The imaging unit rotatingly moves around a subject, captures images of the subject from a plurality of different positions including a prescribed reference position, and generates a plurality of original image data including information representing the prescribed reference position. The control unit corrects the reference position according to deviations between a direction of the subject and a direction from the subject to the prescribed reference position, and causes the imaging unit to capture images of the subject with the corrected reference position used as the reference. The reconstruction unit generates a reconstructed image by reconstructing the plurality of original image data generated by the imaging unit on the basis of the corrected reference position.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The embodiments disclosed in this specification and the drawings relate to a medical image diagnostic apparatus, a control method for a medical image diagnostic apparatus, and a program. [Background technology]

[0002] X-ray CT (Computed Tomography) devices capture images of a subject while rotating a pair of an X-ray tube and an X-ray detector at high speed around the subject, and then reconstruct the resulting multiple projection data to generate a tomographic image of the subject. Conventional X-ray CT devices reconstruct images using multiple projection data collected at a specific position inside the gantry (e.g., the reference position of the X-ray tube). Hereinafter, the image obtained by reconstruction is referred to as a "reconstructed image." Figure 9 is a schematic diagram showing the direction of the reference position of a conventional X-ray CT device and the orientation of a reconstructed image. As shown in Figure 9, conventional X-ray CT devices generally capture images of subjects in a supine position on the top of a bed device. Therefore, conventional X-ray CT devices reconstruct images so that the top of the gantry (i.e., the 0-degree direction of the rotating part inside the gantry) is basically the top of the reconstructed image.

[0003] Among the recent X-ray CT systems, there are universal X-ray CT systems whose gantry can be moved up and down, left and right, and diagonally. Figure 10 is a schematic diagram showing an example of the direction of the reference position of a universal X-ray CT system and the orientation of the reconstructed image. As shown in Figure 10, the universal X-ray CT system can also capture images of subjects in a standing or sitting position. Compared to imaging in a supine position, when imaging in a standing or sitting position, the subject can easily change their body orientation, which makes it more likely that a discrepancy will occur between the orientation of the subject's body in the reconstructed image and the direction of the reference position.

[0004] FIG. 11 shows an example of a reconstructed image obtained when the subject is photographed in a supine position and an example of a reconstructed image obtained when the subject is photographed in a standing position. For example, when the subject is photographed in a standing position as shown in FIG. 11, if the orientation of the subject's body in the reconstructed image is misaligned with the direction of the reference position, it may be difficult to perform a diagnosis, such as interpretation of the image. Therefore, it is desirable to correct such misalignment by performing image processing to rotate the orientation of the reconstructed image. FIG. 12 shows an example of the rotation processing of the reconstructed image.

[0005] However, when an image is rotated, image noise that blurs the edges may occur depending on the rotation angle. Furthermore, the need for such image processing increases the time required to reconstruct the image. Furthermore, when noise reduction processing is performed using artificial intelligence (AI), for example, the noise reduction effect may be reduced if a reconstructed image in which the subject's body is facing in a different direction from the specified direction is input. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2022-65380 Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved by the embodiments disclosed in this specification and the drawings is to easily generate a reconstructed image in which the subject faces a desired direction without degrading image quality. However, the problem to be solved by the embodiments disclosed in this specification and the drawings is not limited to the above problem. Problems corresponding to the effects of each configuration shown in the embodiments described below can also be positioned as other problems. [Means for solving the problem]

[0008] A medical image diagnostic apparatus according to an embodiment includes an imaging unit, a control unit, and a reconstruction unit. The imaging unit rotates around the subject to image the subject from multiple different positions including a predetermined reference position, and generates multiple original image data including information indicating the predetermined reference position. The control unit corrects the reference position according to a deviation between the orientation of the subject and a direction from the subject toward the predetermined reference position, and causes the imaging unit to image the subject based on the corrected reference position. The reconstruction unit generates a reconstructed image by reconstructing the multiple original image data generated by the imaging unit based on the corrected reference position. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a configuration diagram of an X-ray CT apparatus 1 according to an embodiment. [Figure 2] 1 is a diagram showing the appearance of an X-ray CT device 1. FIG. [Figure 3] 1 is a perspective view of an X-ray CT apparatus 1 for examining a subject P in a supine position. [Figure 4] 1 is a perspective view of an X-ray CT apparatus 1 for examining a subject P in a standing position. [Figure 5] 4 is a flowchart showing the operation of the X-ray CT apparatus 1 in the first embodiment. [Figure 6] 10 is a flowchart showing the operation of the X-ray CT apparatus 1 in the second embodiment. [Figure 7] 10 is a flowchart showing the operation of the X-ray CT apparatus 1 in the third embodiment. [Figure 8] 10 is a flowchart showing the operation of the X-ray CT apparatus 1 in the fourth embodiment. [Figure 9] 1 is a schematic diagram showing the direction of the reference position and the orientation of the reconstructed image in a conventional X-ray CT apparatus. [Figure 10] 1 is a schematic diagram showing an example of the direction of the reference position of a universal X-ray CT scanner and the orientation of a reconstructed image. [Figure 11] 10A and 10B are diagrams showing examples of a reconstructed image when imaging in a supine position and a reconstructed image when imaging in an upright position. [Figure 12] FIG. 10 is a diagram showing an example of a rotation process of a reconstructed image. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, a medical imaging diagnostic apparatus, a control method for a medical imaging diagnostic apparatus, and a program according to embodiments will be described with reference to the drawings. The X-ray CT apparatus described below is an example of the medical imaging diagnostic apparatus of the present invention. However, the medical imaging diagnostic apparatus of the present invention is not limited to an X-ray CT apparatus, and may be any other apparatus that captures images while rotating an imaging unit around a subject.

[0011] An X-ray CT scanner is a medical device that includes a gantry with an opening through which a subject can be inserted, a gantry drive device that moves the gantry relative to the subject, and a support on which the subject is placed. The gantry drive device can move the gantry up, down, left, right, and diagonally, allowing the subject to be scanned whether in a supine, standing, or sitting position. The X-ray CT scanner is, for example, a universal X-ray CT scanner.

[0012] FIG. 1 is a configuration diagram of an X-ray CT apparatus 1 according to an embodiment. FIG. 2 is a diagram showing the appearance of the X-ray CT apparatus 1. The X-ray CT apparatus 1 includes, for example, a gantry 10, a bed apparatus 30, and a console apparatus 40. For convenience of explanation, FIG. 1 shows both a view of the gantry 10 from the Z-axis direction and a view from the X-axis direction, but in reality, there is only one gantry 10. In this embodiment, the rotation axis of the rotating frame 17 in a non-tilted state, which is aligned horizontally, or the longitudinal direction of the tabletop 33 of the bed apparatus 30 is defined as the Z-axis direction (front-back direction), an axis perpendicular to the Z-axis direction and horizontal to the floor surface is defined as the X-axis direction, and a direction perpendicular to the Z-axis direction and vertical to the floor surface is defined as the Y-axis direction (up-down direction).

[0013] The gantry device 10 in the X-ray CT apparatus 1 includes, for example, a gantry 20, a gantry drive device 22, and a control device 24. The gantry 20 is supported by the gantry drive device 22. The gantry drive device 22 can move the gantry 20 in the up, down, left, and right directions, and can tilt the gantry 20 to change the orientation of the gantry 20. The control device 24 controls the operation of the gantry drive device 22.

[0014] The gantry 20 includes an X-ray tube 11, a wedge 12, a collimator 13, an X-ray high voltage device 14, an X-ray detector 15, a data acquisition system (DAS) 16, a rotating frame 17, and a cover 18. The X-ray tube 11, the wedge 12, the collimator 13, the X-ray high voltage device 14, the X-ray detector 15, the DAS 16, and the rotating frame 17 are housed in the cover 18.

[0015] The X-ray tube 11 generates X-rays by irradiating thermoelectrons from a cathode (filament) to an anode (target) when a high voltage is applied from the X-ray high voltage device 14. The X-ray tube 11 irradiates the X-rays onto the subject P. The X-ray tube 11 includes a vacuum tube. For example, the X-ray tube 11 is a rotating anode type X-ray tube that generates X-rays by irradiating a rotating anode with thermoelectrons.

[0016] The wedge 12 is a filter for adjusting the amount of X-rays (radiation dose) irradiated from the X-ray tube 11 to the subject (image object) P. The wedge 12 attenuates the X-rays that pass through it so that the distribution of the X-ray dose irradiated from the X-ray tube 11 to the subject P becomes a predetermined distribution. The wedge 12 is also called a wedge filter or a bow-tie filter. The wedge 12 is made by processing aluminum to have a predetermined target angle and a predetermined thickness, for example.

[0017] The collimator 13 is a mechanism for narrowing the irradiation range of the X-rays that have passed through the wedge 12. The collimator 13 narrows the irradiation range of the X-rays, for example, by forming a slit using a combination of multiple lead plates. The collimator 13 is sometimes called an X-ray aperture. The collimator 13 may be an active collimator whose narrowing range can be mechanically driven.

[0018] The X-ray high voltage device 14 includes, for example, a high voltage generator and an X-ray control device. The high voltage generator has an electric circuit including a transformer and a rectifier, and generates a high voltage to be applied to the X-ray tube 11. The X-ray control device controls the output voltage of the high voltage generator according to the X-ray dose to be generated by the X-ray tube 11. The high voltage generator may be one that boosts voltage using the above-mentioned transformer, or one that boosts voltage using an inverter. The X-ray high voltage device 14 may be provided on the rotating frame 17, or may be provided on the side of the fixed frame (not shown) of the gantry device 10.

[0019] The X-ray detector 15 detects the intensity of X-rays generated by the X-ray tube 11 and incident upon the subject P. The X-ray detector 15 outputs an electrical signal (which may be an optical signal, etc.) corresponding to the intensity of the detected X-rays to the DAS 16. The X-ray detector 15 has, for example, multiple X-ray detection element rows. Each of the multiple X-ray detection element rows has multiple X-ray detection elements arranged in the channel direction along an arc centered on the focal point of the X-ray tube 11. The multiple X-ray detection element rows are arranged in the slice direction (column direction, row direction).

[0020] The X-ray detector 15 is, for example, an indirect detector having a grid, a scintillator array, and a photosensor array. The scintillator array has multiple scintillators. Each scintillator has scintillator crystals. The scintillator crystals emit light with an amount of light corresponding to the intensity of incident X-rays. The grid is arranged on the surface of the scintillator array on which X-rays are incident and has an X-ray shielding plate that has the function of absorbing scattered X-rays. The grid is sometimes called a collimator (one-dimensional collimator or two-dimensional collimator). The photosensor array has, for example, a photosensor such as a photomultiplier tube (PMT). The photosensor array outputs an electrical signal corresponding to the amount of light emitted by the scintillator. The X-ray detector 15 may also be a direct conversion detector having a semiconductor element that converts incident X-rays into an electrical signal.

[0021] The DAS 16 includes, for example, an amplifier, an integrator, and an A / D (Analog to Digital) converter. The amplifier amplifies the electrical signal output by each X-ray detection element of the X-ray detector 15. The integrator integrates the amplified electrical signal over a view period (described below). The A / D converter converts the electrical signal indicating the integration result into a digital signal. The DAS 16 outputs detection data based on the digital signal to the console device 40. The detection data is a digital value of X-ray intensity identified by the channel number and column number of the X-ray detection element that generated the data, and a view number indicating the acquired view. The view number is a number that changes according to the rotation of the rotating frame 17, and is, for example, a number that is incremented according to the rotation of the rotating frame 17. Therefore, the view number is information that indicates the rotation angle of the X-ray tube 11. The view period is the period from the rotation angle corresponding to a certain view number to the rotation angle corresponding to the next view number.

[0022] The DAS 16 may detect the view switching by a timing signal input from the control device 24, by an internal timer, or by a signal acquired from a sensor (not shown). When a full scan is performed and X-rays are continuously emitted by the X-ray tube 11, the DAS 16 collects a group of detection data for the entire circumference (360 degrees). When a half scan is performed and X-rays are continuously emitted by the X-ray tube 11, the DAS 16 collects detection data for half the circumference (180 degrees).

[0023] The rotating frame 17 is an annular member that supports the X-ray tube 11, wedge 12, collimator 13, and X-ray detector 15 in opposing positions. The rotating frame 17 is supported by a fixed frame so as to be rotatable around the subject P introduced inside. The rotating frame 17 also supports the DAS 16. Detection data output by the DAS 16 is transmitted by optical communication from a transmitter having a light-emitting diode (LED) provided on the rotating frame 17 to a receiver having a photodiode provided on a non-rotating portion of the gantry device 10 (e.g., the fixed frame), and then transferred to the console device 40 by the receiver. Note that the method of transmitting the detection data from the rotating frame 17 to the non-rotating portion is not limited to the above-mentioned method using optical communication, and any non-contact transmission method may be adopted. The rotating frame 17 is not limited to an annular member, and may be an arm-like member as long as it can support and rotate the X-ray tube 11 and the like.

[0024] A central opening 19 is provided in the cover 18. The central opening 19 is an opening through which the subject P is inserted. A rotating frame 17 is provided inside the cover 18 and is disposed inside the cover 18, surrounding the central opening 19. The rotating frame 17 rotates around the central opening 19.

[0025] The X-ray CT device 1 is, for example, a Rotate / Rotate-Type X-ray CT device (third generation CT) in which both the X-ray tube 11 and the X-ray detector 15 are supported by a rotating frame 17 and rotate around the subject P, but is not limited to this and may also be a Stationary / Rotate-Type X-ray CT device (fourth generation CT) in which multiple X-ray detection elements arranged in a circular ring are fixed to a fixed frame and the X-ray tube 11 rotates around the subject P.

[0026] The gantry drive device 22 includes, for example, a base 101, a horizontal movement device 102, a support column 103, a rail 104, a slider 105, and a tilt mechanism 106. The base 101 includes, for example, a linear support structure extending horizontally. For example, the base 101 is fixed to the floor of a consultation room with bolts or the like.

[0027] The horizontal movement device 102 is provided on the base 101, and a support column 103 is mounted on the horizontal movement device 102 in an upright state. The support column 103 is, for example, a member extending in the vertical direction. The horizontal movement device 102 moves the support column 103, which is an object mounted thereon, in the horizontal direction based on the control of the control device 24.

[0028] A rail 104 is attached to the support column 103. The rail 104 is arranged along the extension direction (vertical direction) of the support column 103. A slider 105 is attached to the rail 104. The slider 105 is movable along the rail 104 under the control of the control device 24.

[0029] A tilt mechanism 106 is attached to the slider 105, and a gantry 20 is attached to the tilt mechanism 106. The tilt mechanism 106 is capable of tilting the gantry 20 around a rotation axis based on the control of the control device 24. The tilt mechanism 106 switches the orientation of the gantry 20 by tilting the gantry 20. The gantry drive device 22 moves the support column 103 using the horizontal movement device 102, thereby moving the gantry 20 in the horizontal direction.

[0030] The gantry driving device 22 moves the gantry 20 in the vertical direction by moving the slider 105 along the rails 104. The gantry driving device 22 tilts the gantry 20 around a rotation axis using the tilt mechanism 106. The gantry driving device 22 moves the gantry 20, thereby moving the gantry 20 and the subject P relative to each other.

[0031] The control device 24 has, for example, a processing circuit having a processor such as a central processing unit (CPU), and a drive mechanism including a motor, an actuator, etc. The processing circuit realizes these functions by, for example, a hardware processor executing a program stored in a storage device (storage circuit).

[0032] A hardware processor refers to a circuit such as a CPU, a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), a programmable logic device (e.g., a simple programmable logic device (SPLD) or a complex programmable logic device (CPLD)), or a field programmable gate array (FPGA). Instead of storing a program in a memory device, a hardware processor may be configured so that the program is directly embedded in the circuit. In this case, the hardware processor performs its functions by reading and executing the program embedded in the circuit. A hardware processor is not limited to a single circuit, but may be configured as a single hardware processor by combining multiple independent circuits to perform each function. A memory device may be a non-transitory (hardware) storage medium. Furthermore, multiple components may be integrated into a single hardware processor to perform each function.

[0033] The control device 24, for example, rotates the rotating frame 17, moves the gantry 20 using the gantry drive device 22, and moves the top board 33 of the bed device 30. The top board 33 serves as a bed on which the subject P is placed in a supine position. For example, when tilting the gantry 20, the control device 24 controls the tilt mechanism 106 of the gantry drive device 22 to rotate the rotating frame 17 about an axis parallel to the Z-axis direction based on the inclination angle (tilt angle) input to the input interface 43.

[0034] The control device 24 grasps the rotation angle of the rotating frame 17 by the output of a sensor (not shown), etc. The control device 24 also provides the rotation angle of the rotating frame 17 to the processing circuit 50 as needed. The control device 24 may be provided in the gantry device 10 or in the console device 40. The control device 24 moves the gantry 20 along the rails 104 to perform a main scan, or to perform scanogram imaging, which is a positioning image performed before the main scan. The scanogram is, for example, an image captured from the side of the subject P. The control device 24 outputs the scanogram to a trajectory setting function 55 of the console device 40.

[0035] The control device 24 controls the gantry drive device 22 to move the gantry 20 along a predetermined trajectory, and also causes the X-ray detector 15 to detect the X-rays irradiated by the X-ray tube 11, thereby scanning the subject P. The predetermined trajectory is, for example, a trajectory set by a trajectory setting function 55, which will be described later.

[0036] The bed device 30 is a device on which the subject P to be scanned is placed and moved, and introduced into the rotating frame 17 of the gantry device 10. The bed device 30 includes, for example, a base 31, a bed driving device 32, a top plate 33, and a support frame 34.

[0037] The base 31 includes a housing that supports the support frame 34 so that it can move in the vertical direction (Y-axis direction). The bed driving device 32 includes a motor and an actuator. The bed driving device 32 moves the top plate 33, on which the subject P is placed, along the support frame 34 in the longitudinal direction of the top plate 33 (Z-axis direction). The top plate 33 is a plate-shaped member on which the subject P is placed. The bed driving device 32 moves the top plate 33 backward to insert it into the opening of the gantry 20. The bed driving device 32 moves the top plate 33 forward to withdraw it from the gantry 20.

[0038] The bed driving device 32 may move not only the tabletop 33 but also the support frame 34 in the longitudinal direction of the tabletop 33. Conversely to the above, the gantry 10 may be movable in the Z-axis direction, and the rotation frame 17 may be controlled to come around the subject P by the movement of the gantry 10. Alternatively, both the gantry 10 and the tabletop 33 may be configured to be movable.

[0039] FIG. 3 is a perspective view of the X-ray CT apparatus 1 for examining a subject P in a supine position. FIG. 4 is a perspective view of the X-ray CT apparatus 1 for examining a subject P in an upright position. The subject P placed on the bed apparatus 30 is examined in a supine position as shown in FIG. 3. The X-ray CT apparatus 1 can also examine a subject P in a standing position as shown in FIG. 4. When examining a subject P in a standing position, for example, a support apparatus for supporting the subject P in a standing position is used. The bed apparatus 30 may be provided with, for example, a displacement structure for displacing the subject P between a supine position and an upright position.

[0040] The gantry device 10 and the bed device 30 switch the relative movement direction of the X-ray detector 15 provided on the gantry 20 and the subject P supported on the tabletop 33, for example, by using a horizontal movement device 102, a slider 105, and a bed drive device 32. For example, when scanning the entire body of the subject P arranged parallel to the Z direction, the horizontal movement device 102 moves the gantry 20 together with the support column 103 in the Z direction. When scanning the subject P along an OM line tilted from the Z direction around the X axis, the horizontal movement device 102 and the slider 105 move the gantry 20 in the Z direction and the Y direction.

[0041] The console device 40 includes, for example, a memory 41, a display 42, an input interface 43, and a processing circuit 50. In the embodiment, the console device 40 is described as being separate from the gantry device 10, but the gantry device 10 may include some or all of the components of the console device 40.

[0042] The memory 41 is realized by, for example, a semiconductor memory element such as a RAM (Random Access Memory), a flash memory, a hard disk, an optical disk, etc. The memory 41 stores, for example, detection data, projection data, reconstructed image data, CT image data, etc. These data may be stored in an external memory (not shown) with which the X-ray CT apparatus 1 can communicate, instead of (or in addition to) the memory 41. The external memory is controlled by, for example, a cloud server that manages the external memory, by the cloud server accepting a read / write request.

[0043] The display 42 displays various types of information. For example, the display 42 is an output interface that displays medical images (CT images) generated by a processing circuit, GUI (Graphical User Interface) images that accept various operations by operators such as doctors and engineers, and the like. The display 42 is, for example, a liquid crystal display (LCD), a CRT (Cathode Ray Tube), an organic EL (Electroluminescence) display, or the like. The display 42 may be provided on the gantry device 10. The display 42 may be a desktop type, or may be a display device (for example, a tablet terminal) that can wirelessly communicate with the main body of the console device 40.

[0044] The input interface 43 accepts various input operations by the operator and outputs electrical signals indicating the contents of the accepted input operations to the processing circuitry 50. For example, the input interface 43 accepts input operations such as acquisition conditions for acquiring detection data or projection data, reconstruction conditions for reconstructing CT images, and image processing conditions for generating post-processed images from CT images. The input interface 43 is realized by, for example, a mouse, a keyboard, a touch panel, a drag ball, a switch, a button, a joystick, a camera, an infrared sensor, a microphone, etc. The input interface 43 may also be realized by a display device (e.g., a tablet terminal) capable of wireless communication with the main body of the console device 40. The input interface 43 outputs electrical signals for setting a scan trajectory to the processing circuitry 50 based on the operator's operation.

[0045] In this specification, the input interface is not limited to an interface having physical operation parts such as a mouse, keyboard, etc. For example, an example of an input interface also includes an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the device and outputs this electrical signal to a control circuit.

[0046] The processing circuitry 50 controls the overall operation of the X-ray CT apparatus 1. The processing circuitry 50 includes, for example, a control function 51, a pre-processing function 52, a reconstruction processing function 53, an image processing function 54, and a trajectory setting function 55. The processing circuitry 50 realizes these functions by, for example, a hardware processor executing a program stored in a storage device (storage circuit).

[0047] A hardware processor refers to a circuit such as a CPU, GPU, application-specific integrated circuit, programmable logic device or composite programmable logic device, or field programmable gate array. Instead of storing a program in a storage device, the program may be directly embedded in the circuit of the hardware processor. A hardware processor is not limited to a single circuit, but may be configured as a single hardware processor by combining multiple independent circuits to realize each function. The storage device may be a non-transitory (hardware) storage medium. Furthermore, multiple components may be integrated into a single hardware processor to realize each function.

[0048] Each component of the console device 40 or the processing circuitry 50 may be distributed and realized by multiple pieces of hardware. The processing circuitry 50 may not be a component of the console device 40, but may be realized by a processing device capable of communicating with the console device 40. The processing device is, for example, a workstation connected to one X-ray CT device, or a device (for example, a cloud server) connected to multiple X-ray CT devices and collectively executing processing equivalent to that of the processing circuitry 50 described below.

[0049] The control function 51 controls various functions of the processing circuit 50 based on input operations received by the input interface 43. For example, the control function 51 controls the X-ray high voltage device 14, the DAS 16, the control device 24, and the bed driving device 32 of the bed device 30 to perform processing such as collection of detection data in the gantry device 10.

[0050] The pre-processing function 52 performs pre-processing such as logarithmic conversion processing, offset correction processing, inter-channel sensitivity correction processing, and beam hardening correction on the detection data output by the DAS 16, generates projection data, and stores the generated projection data in the memory 41.

[0051] The reconstruction processing function 53 performs reconstruction processing using a filtered back projection method, an iterative reconstruction method, or the like on the projection data set by the preprocessing function 52 to generate CT image data, and stores the generated CT image data in the memory 41.

[0052] The image processing function 54 converts the CT image data into three-dimensional image data or cross-sectional image data of an arbitrary cross section by a known method based on the input operation received by the input interface 43. The conversion into three-dimensional image data may be performed by the pre-processing function 52.

[0053] Setting information for setting a trajectory is input to the trajectory setting function 55 based on an input operation of the operator received by the input interface 43. The trajectory setting function 55 sets a scan trajectory for scanning the subject P based on the input setting information.

[0054] When setting a scan trajectory, the trajectory setting function 55 displays a trajectory setting image including an image showing the outline of the subject P on the display 42. The trajectory setting function 55 acquires a scanogram output by the control device 24. The trajectory setting function 55 displays the scanogram on the display 42 and sets a scan trajectory. Note that the X-ray CT device 1 does not necessarily have to be equipped with the trajectory setting function 55.

[0055] A method for generating a reconstructed image corrected to an arbitrary direction using the X-ray CT apparatus 1 of the embodiment will be described below.

[0056] As described above, the X-ray CT system 1 of the embodiment is a universal X-ray CT system capable of capturing images of subjects in various positions, such as standing and sitting. Because subjects can easily change their body orientation when capturing images in standing or sitting positions, misalignment can easily occur between the subject's body orientation in the reconstructed image and the direction of the reference position. Such misalignment can make diagnostics, such as image interpretation, difficult. Furthermore, when correcting such misalignment by performing image processing to rotate the orientation of the reconstructed image, image noise, such as blurred edges, can occur depending on the rotation angle. Furthermore, such image processing can increase the time required for image reconstruction. Furthermore, when performing noise reduction processing using AI, the noise reduction effect can be reduced if a reconstructed image is input in which the subject's body orientation is different from the specified direction.

[0057] To address these issues, the X-ray CT apparatus 1 of the embodiment corrects the reference position of the X-ray tube before reconstructing an image, thereby enabling the generation of a reconstructed image corrected in any orientation without degrading the image quality of the reconstructed image. Furthermore, the X-ray CT apparatus 1 of the embodiment does not require image processing such as image rotation, thereby preventing an increase in the time required for image reconstruction. Furthermore, because the X-ray CT apparatus 1 of the embodiment can generate a reconstructed image corrected in any orientation, it is possible to prevent a degradation in the noise reduction effect when performing noise reduction processing using AI.

[0058] The specific configuration is as follows: In the case of a conventional X-ray CT device, an image is generally reconstructed so that the upward direction of the gantry (i.e., the 0-degree direction of the rotating part inside the gantry) is the upward direction of the reconstructed image. In contrast, the X-ray CT device 1 of the embodiment performs correction before reconstructing an image so that a desired direction in the gantry 20 becomes the reference position of the X-ray tube 11. Then, the X-ray CT device 1 reconstructs an image so that the direction of the corrected reference position becomes the upward direction of the reconstructed image.

[0059] Four embodiments of the correction process for correcting the reference position of the X-ray tube 11 in a desired direction will be described below. In the first embodiment described below, a correction process for physically correcting the reference position of the X-ray tube 11 by starting collection of detection data when the rotation angle of the rotating frame 17 reaches a desired angle will be described. In addition, in the second to fourth embodiments described below, a correction process for correcting the reference position of the X-ray tube 11 on the detection data by correcting the detection data used to generate a reconstructed image will be described. In the second embodiment, the detection data is corrected on the gantry device 10 side when the detection data is collected. In the third embodiment, the detection data is corrected on the console device 40 side when the detection data is saved. In the fourth embodiment, the detection data is corrected on the console device 40 side during pre-processing for image reconstruction.

[0060] The method for correcting the reference position of the X-ray tube 11 is not limited to the correction processing methods of these four embodiments, and other methods may also be used.

[0061] The correction process of the first embodiment will be described below.

[0062] The X-ray CT apparatus 1 in the first embodiment has a configuration that starts collecting detection data at the timing when the rotation angle of the rotating frame 17 reaches a desired angle. Fig. 5 is a flowchart showing the operation of the X-ray CT apparatus 1 in the first embodiment.

[0063] The control function 51 of the console device 40 acquires information indicating the amount of offset (step S101). The amount of offset here is information indicating the magnitude of deviation between the orientation of the initial reference position of the X-ray tube 11 and the orientation of the subject. The orientation of the initial reference position of the X-ray tube 11 is, for example, the upward direction of the gantry 20 (the 0-degree direction of the rotating frame 17 inside the gantry), which is the reference position in a conventional X-ray CT device. However, the orientation of the initial reference position of the X-ray tube 11 may be any predetermined direction.

[0064] The control function 51 acquires information indicating the offset amount, for example, from the input interface 43. In this case, information indicating the offset amount generated based on an input operation by the operator received by the input interface 43 is input to the control function 51. For example, a subject in a standing or sitting position under the gantry 20 is displayed on the display 42. The operator specifies the required offset amount by visually checking the orientation of the subject's body displayed on the display 42. The operator operates the input interface 43 to input the specified offset amount.

[0065] Alternatively, the operator may manually rotate the image so that the orientation of the initial reference position of the X-ray tube 11 matches the orientation of the subject's body displayed on the display 42, and determine the offset amount from the amount of rotation.

[0066] Alternatively, the X-ray CT device 1 or a sensor (not shown) installed near the X-ray CT device 1 may be configured to automatically detect the orientation of the subject's body and output information indicating the offset amount to the control function 51. In this case, for example, the orientation of the subject's body may be detected based on the longitudinal direction and the lateral direction of the cross-sectional image of the subject's body. In this way, any method can be used to specify the required offset amount.

[0067] The control function 51 determines the detection data collection start position based on the information indicating the acquired offset amount (step S102). Here, as an example, it is assumed that a reconstructed image is generated using the detection data collection start position as a reference position. For example, inside the gantry 20, multiple sensors (not shown) are installed at predetermined intervals along the trajectory of the X-ray tube 11, which moves as the rotating frame 17 rotates. The closer the intervals between these multiple sensors (i.e., the more sensors installed), the more accurately the deviation can be corrected. These sensors detect the X-ray tube 11 passing in front of the device itself. The control function 51 starts collection of detection data by the X-ray tube 11, the X-ray detector 15, and the DAS 16 when a sensor installed near the determined detection data collection start position detects the passage of the X-ray tube 11 (step S103). This allows the actual collection of detection data to be started from the determined detection data collection start position.

[0068] The DAS 16 collects detection data for the entire circumference (360 degrees) and outputs the collected detection data group to the console device 40 (step S104). The console device 40 stores the detection data output from the DAS 16 in the memory 41 (step S105). Thereafter, the console device 40 waits until it is time to generate a reconstructed image, for example.

[0069] The pre-processing function 52 reads out the detection data stored in the memory 41 (step S106). The pre-processing function 52 performs pre-processing such as logarithmic conversion, offset correction, inter-channel sensitivity correction, and beam hardening correction on the read out detection data to generate projection data. The reconstruction processing function 53 performs reconstruction processing such as filtered back projection or iterative reconstruction on the multiple projection data generated by the pre-processing function 52 to generate reconstructed image data (CT image data) (step S107).

[0070] The image processing function 54 converts the CT image data into cross-sectional image data of an arbitrary cross section by a known method based on the input operation received by the input interface 43 (step S108). Note that the image processing function 54 may also convert the CT image data into three-dimensional image data by a known method. This completes the operation of the X-ray CT apparatus 1 of the first embodiment shown in the flowchart of FIG. 5.

[0071] As described above, the X-ray CT apparatus 1 in the first embodiment determines the collection start position of the detection data in accordance with the deviation between the orientation of the subject and the reference position. Then, the X-ray CT apparatus 1 in the first embodiment generates projection data from the collected detection data using the determined position as the reference position, and generates a reconstructed image. In this way, the X-ray CT apparatus 1 in the first embodiment has a configuration in which the reference position is corrected in advance before generating a reconstructed image, so that a reconstructed image in a desired orientation can be easily generated without requiring subsequent image processing such as image rotation.

[0072] The correction process of the second embodiment will be described below.

[0073] The X-ray CT apparatus 1 in the second embodiment has a configuration for correcting the reference position of the X-ray tube 11 on the detection data by correcting the detection data used to generate a reconstructed image. In the second embodiment, the correction of the detection data is performed on the gantry device 10 side when the detection data is collected. Fig. 6 is a flowchart showing the operation of the X-ray CT apparatus 1 in the second embodiment.

[0074] The DAS 16 of the gantry device 10 acquires information indicating the offset amount (step S201). As described above, the offset amount is angle information indicating the deviation between the orientation of the initial reference position of the X-ray tube 11 and the orientation of the subject. The orientation of the initial reference position of the X-ray tube 11 is, for example, the upward direction of the gantry 20 (the 0-degree direction of the rotating frame 17 inside the gantry), which is the reference position in a conventional X-ray CT device. However, the orientation of the initial reference position of the X-ray tube 11 may be any predetermined direction.

[0075] The DAS 16 acquires information indicating the offset amount from, for example, the input interface 43. In this case, information indicating the offset amount generated based on an input operation by an operator received by the input interface 43 is input to the DAS 16. Note that a configuration may also be adopted in which the X-ray CT device 1 or a sensor (not shown) installed near the X-ray CT device 1 detects the orientation of the subject's body and outputs information indicating the offset amount to the DAS 16.

[0076] The control function 51 causes the X-ray tube 11, the X-ray detector 15, and the DAS 16 to start collecting detection data (step S202). The DAS 16 collects detection data for the entire circumference (360 degrees). The DAS 16 corrects the collected detection data group to correct the reference position of the X-ray tube 11 (step S203).

[0077] Specifically, the DAS 16 corrects, for example, the view number included in the detection data. As described above, the view number is a number that changes according to the rotation of the rotating frame 17, for example, a number that is incremented according to the rotation of the rotating frame 17. Therefore, the view number is information that indicates the rotation angle of the X-ray tube 11. The DAS 16 corrects the view number based on information that indicates the acquired offset amount. For example, if the value of the view number is the value of the rotation angle itself from the initial reference position of the X-ray tube 11, the DAS 16 corrects the value of the view number by incrementing it by the value of the offset amount.

[0078] The DAS 16 outputs the corrected detection data group to the console device 40 (step S204). The console device 40 stores the detection data output from the DAS 16 in the memory 41 (step S205). Thereafter, the console device 40 waits until it is time to generate a reconstructed image, for example.

[0079] The pre-processing function 52 reads out the detection data stored in the memory 41 (step S206). The pre-processing function 52 performs pre-processing such as logarithmic conversion, offset correction, inter-channel sensitivity correction, and beam hardening correction on the read out detection data to generate projection data. The reconstruction processing function 53 performs reconstruction processing such as filtered back projection or iterative reconstruction on the multiple projection data generated by the pre-processing function 52 to generate reconstructed image data (CT image data) (step S207).

[0080] The image processing function 54 converts the CT image data into cross-sectional image data of an arbitrary cross section by a known method based on the input operation received by the input interface 43 (step S208). Note that the image processing function 54 may also convert the CT image data into three-dimensional image data by a known method. This completes the operation of the X-ray CT apparatus 1 of the second embodiment shown in the flowchart of FIG. 6.

[0081] As described above, the X-ray CT apparatus 1 in the second embodiment corrects the view number included in the detection data in accordance with the deviation between the orientation of the subject and the reference position. Then, the X-ray CT apparatus 1 in the second embodiment generates projection data from the collected detection data based on the corrected view number, and generates a reconstructed image. As described above, the X-ray CT apparatus 1 in the second embodiment has a configuration in which the reference position is corrected by changing the view number included in the detection data in advance before generating a reconstructed image. Therefore, it is possible to easily generate a reconstructed image in a desired orientation without requiring subsequent image processing such as image rotation.

[0082] The correction process of the third embodiment will be described below.

[0083] The X-ray CT apparatus 1 in the third embodiment has a configuration for correcting the reference position of the X-ray tube 11 on the detection data by correcting the detection data used to generate a reconstructed image. In the third embodiment, the correction of the detection data is performed on the console device 40 side when the detection data is saved. Fig. 7 is a flowchart showing the operation of the X-ray CT apparatus 1 in the third embodiment.

[0084] The control function 51 of the console device 40 acquires information indicating the offset amount (step S301). As described above, the offset amount is angle information indicating the deviation between the orientation of the initial reference position of the X-ray tube 11 and the orientation of the subject. The orientation of the initial reference position of the X-ray tube 11 is, for example, the upward direction of the gantry 20 (the 0-degree direction of the rotating frame 17 inside the gantry), which is the reference position in a conventional X-ray CT device. However, the orientation of the initial reference position of the X-ray tube 11 may be any predetermined direction.

[0085] The control function 51 acquires information indicating the offset amount, for example, from the input interface 43. In this case, information indicating the offset amount generated based on an input operation by an operator received by the input interface 43 is input to the control function 51. Note that a configuration may also be adopted in which the X-ray CT device 1 or a sensor (not shown) installed near the X-ray CT device 1 detects the orientation of the subject's body and outputs information indicating the offset amount to the DAS 16.

[0086] The control function 51 causes the X-ray tube 11, the X-ray detector 15, and the DAS 16 to start collecting detection data (step S302). The DAS 16 of the gantry device 10 collects detection data for the entire circumference (360 degrees) and outputs the collected detection data group to the console device 40 (step S303). The control function 51 corrects the detection data group output from the DAS 16 to correct the reference position of the X-ray tube 11 (step S304).

[0087] The control function 51 corrects the view number included in the detection data, for example, as described above. As described above, the view number is a number that changes according to the rotation of the rotating frame 17, for example, a number that is incremented according to the rotation of the rotating frame 17. The control function 51 corrects the view number based on information indicating the acquired offset amount. The control function 51 stores the corrected detection data group in the memory 41 (step S305). Thereafter, the console device 40 waits, for example, until it is time to generate a reconstructed image.

[0088] The pre-processing function 52 reads out the detection data stored in the memory 41 (step S306). The pre-processing function 52 performs pre-processing such as logarithmic conversion, offset correction, inter-channel sensitivity correction, and beam hardening correction on the read out detection data to generate projection data. The reconstruction processing function 53 performs reconstruction processing such as filtered back projection or iterative reconstruction on the multiple projection data generated by the pre-processing function 52 to generate reconstructed image data (CT image data) (step S307).

[0089] The image processing function 54 converts the CT image data into cross-sectional image data of an arbitrary cross section by a known method based on the input operation received by the input interface 43 (step S308). Note that the image processing function 54 may also convert the CT image data into three-dimensional image data by a known method. This completes the operation of the X-ray CT apparatus 1 of the third embodiment shown in the flowchart of FIG. 7.

[0090] As described above, the X-ray CT apparatus 1 in the third embodiment corrects the view number included in the detection data in accordance with the deviation between the orientation of the subject and the reference position. Then, the X-ray CT apparatus 1 in the third embodiment generates projection data from the collected detection data based on the corrected view number, and generates a reconstructed image. As described above, the X-ray CT apparatus 1 in the second embodiment has a configuration in which the reference position is corrected by changing the view number included in the detection data in advance before generating a reconstructed image. Therefore, it is possible to easily generate a reconstructed image in a desired orientation without requiring subsequent image processing such as image rotation.

[0091] The correction process of the fourth embodiment will be described below.

[0092] The X-ray CT apparatus 1 in the fourth embodiment has a configuration for correcting the reference position of the X-ray tube 11 on the detection data by correcting the detection data used to generate a reconstructed image. In the fourth embodiment, the correction of the detection data is performed on the console device 40 side during preprocessing for image reconstruction. Fig. 8 is a flowchart showing the operation of the X-ray CT apparatus 1 in the fourth embodiment.

[0093] The control function 51 of the console device 40 acquires information indicating the offset amount (step S401). As described above, the offset amount is angle information indicating the deviation between the orientation of the initial reference position of the X-ray tube 11 and the orientation of the subject. The orientation of the initial reference position of the X-ray tube 11 is, for example, the upward direction of the gantry 20 (the 0-degree direction of the rotating frame 17 inside the gantry), which is the reference position in a conventional X-ray CT device. However, the orientation of the initial reference position of the X-ray tube 11 may be any predetermined direction.

[0094] The control function 51 acquires information indicating the offset amount, for example, from the input interface 43. In this case, information indicating the offset amount generated based on an input operation by an operator received by the input interface 43 is input to the control function 51. Note that a configuration may also be adopted in which the X-ray CT device 1 or a sensor (not shown) installed near the X-ray CT device 1 detects the orientation of the subject's body and outputs information indicating the offset amount to the DAS 16.

[0095] The control function 51 causes the X-ray tube 11, the X-ray detector 15, and the DAS 16 to start collecting detection data (step S402). The DAS 16 of the gantry device 10 collects detection data for the entire circumference (360 degrees) and outputs the collected detection data group to the console device 40 (step S403). The console device 40 stores the detection data output from the DAS 16 in the memory 41 (step S404). Thereafter, the console device 40 waits until it is time to generate a reconstructed image, for example.

[0096] The pre-processing function 52 reads out the detection data stored in the memory 41 (step S405). The pre-processing function 52 corrects the read out detection data group to correct the reference position of the X-ray tube 11 (step S406).

[0097] The pre-processing function 52 corrects the view number included in the detection data, for example, as described above. As described above, the view number is a number that changes according to the rotation of the rotating frame 17, for example, a number that is incremented according to the rotation of the rotating frame 17. The pre-processing function 52 corrects the view number based on information indicating the acquired offset amount.

[0098] The pre-processing function 52 performs pre-processing such as logarithmic conversion, offset correction, inter-channel sensitivity correction, and beam hardening correction on the corrected detection data to generate projection data. The reconstruction processing function 53 performs reconstruction processing such as filtered back projection or iterative reconstruction on the multiple projection data generated by the pre-processing function 52 to generate reconstructed image data (CT image data) (step S407).

[0099] The image processing function 54 converts the CT image data into cross-sectional image data of an arbitrary cross section by a known method based on the input operation received by the input interface 43 (step S408). Note that the image processing function 54 may also convert the CT image data into three-dimensional image data by a known method. This completes the operation of the X-ray CT apparatus 1 of the fourth embodiment shown in the flowchart of FIG. 8.

[0100] As described above, the X-ray CT apparatus 1 in the fourth embodiment corrects the view number included in the detection data in accordance with the deviation between the orientation of the subject and the reference position. Then, the X-ray CT apparatus 1 in the fourth embodiment generates projection data from the collected detection data based on the corrected view number, and generates a reconstructed image. As described above, the X-ray CT apparatus 1 in the fourth embodiment has a configuration in which the reference position is corrected by changing the view number included in the detection data in advance before generating a reconstructed image. Therefore, a reconstructed image in a desired orientation can be easily generated without requiring subsequent image processing such as image rotation.

[0101] In the X-ray CT apparatus 1 of the above embodiment, the gantry 20 is moved to move the gantry 20 relative to the subject P. However, instead of moving the gantry 20, for example, the top board 33 of the bed apparatus 30 may be moved. Alternatively, both the gantry 20 and the top board 33 may be moved.

[0102] In the X-ray CT apparatus 1 of the embodiment, no adjustment is made using the wedge 12 or the collimator 13. However, for example, an active collimator may be used as the wedge 12 or the collimator 13, and unnecessary portions of the projection data may be cut when performing either a helical scan or a volume scan as the scan state. By cutting unnecessary portions of the projection data using the collimator 13, it is possible to reduce the amount of X-ray exposure to the subject P during imaging using the X-ray CT apparatus. Furthermore, the amount of exposure may be reduced by setting at least one of the helical pitch in each section and the tube current of the X-ray tube 11 to be suitable (optimal) for the subject.

[0103] According to at least one of the embodiments described above, the medical image diagnostic apparatus includes an imaging unit that rotates around the subject, images the subject from a plurality of different positions including a predetermined reference position, and generates a plurality of original image data including information indicating the predetermined reference position; a control unit that corrects the reference position in accordance with a deviation between the orientation of the subject and the direction from the subject to the predetermined reference position, and causes the imaging unit to image the subject based on the corrected reference position; and a reconstruction unit that generates a reconstructed image by reconstructing the plurality of original image data generated by the imaging unit based on the corrected reference position, thereby making it possible to easily generate a reconstructed image in which the subject is facing in a desired direction without degrading image quality.

[0104] Furthermore, according to at least one of the embodiments described above, by setting the reference position as the start position of imaging by the imaging unit, it is possible to specify both the reference position and the start position of imaging, thereby simplifying the operations and arithmetic processing for generating a reconstructed image.

[0105] Furthermore, according to at least one of the embodiments described above, the medical image diagnostic apparatus has an imaging unit that rotates around the subject, images the subject from a plurality of different positions including a predetermined reference position, and generates a plurality of original image data including information indicating a relative position with respect to the predetermined reference position; a correction unit that corrects the information indicating the relative position included in the original image data according to a deviation between the orientation of the subject and the direction from the subject to the predetermined reference position; and a reconstruction unit that generates a reconstructed image by reconstructing the plurality of original image data generated by the imaging unit based on the relative positions corrected by the correction unit, thereby making it possible to easily generate a reconstructed image in which the subject is facing in a desired direction without degrading image quality.

[0106] Furthermore, according to at least one of the embodiments described above, by using a view number that increases according to the rotation angle of the imaging unit as the information indicating the relative position, it is possible to easily generate a reconstructed image in which the subject faces a desired direction simply by correcting the view number of a conventional CT apparatus. This also eliminates the need to change the data structure of the detection data, making it possible to easily generate a reconstructed image using a conventional calculation method as is.

[0107] Furthermore, according to at least one of the embodiments described above, by using detection data including the view number and the X-ray intensity value as the original image data, it is possible to correct the reference position before the image is generated, and therefore it is possible to easily generate a reconstructed image without the need for image processing such as image rotation.

[0108] Furthermore, according to at least one of the above-described embodiments, the imaging unit can be configured to include an X-ray tube, an X-ray detector that detects X-rays irradiated by the X-ray tube and passed through the subject, and a gantry on which the X-ray tube and the X-ray detector are installed opposite each other and which has a rotation mechanism that rotates around the subject. That is, the present invention is applicable to general X-ray CT devices and universal X-ray CT devices. Note that the present invention is also applicable to other devices that capture images while rotating the imaging unit around the subject.

[0109] Furthermore, according to at least one of the embodiments described above, even in an apparatus that can be used by switching between imaging in a supine position, an upright position, and a sitting position, such as a universal X-ray CT apparatus, an image in a desired orientation (for example, an image in which the abdomen of the subject faces upward) can be easily generated without requiring additional post-processing. As a result, the X-ray CT apparatus 1 of the embodiment can be used in the same workflow as when using a conventional general X-ray CT apparatus.

[0110] Although several embodiments have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0111] 1...X-ray CT device, 10...mounting device, 11...X-ray tube, 12...wedge, 13...collimator, 14...X-ray high voltage device, 15...X-ray detector, 16...DAS (data acquisition system), 17...rotating frame, 18...cover, 19...central opening, 20...mounting device, 22...mounting device drive unit, 24...control device, 30...bed device, 31...base, 32...bed drive unit, 33...top plate, 34...support frame, 40...console device, 41...memory, 42...display, 43...input interface, 50...processing circuit, 51...control function, 52...preprocessing function, 53...reconstruction processing function, 54...image processing function, 55...trajectory setting function, 101...base, 102...horizontal movement device, 103...support column, 104...rail, 105...slider, 106...tilt mechanism

Claims

1. an imaging unit that rotates around the subject, images the subject from a plurality of different positions including a predetermined reference position, and generates a plurality of raw image data including information indicating the predetermined reference position; a control unit that corrects the reference position according to a deviation between an orientation of the subject and a direction from the subject to the predetermined reference position, and causes the imaging unit to capture an image of the subject based on the corrected reference position; a reconstruction unit that generates a reconstructed image by reconstructing the plurality of pieces of original image data generated by the imaging unit based on the corrected reference position; A medical imaging diagnostic device comprising:

2. The reference position is a start position of the image capturing unit. The medical imaging diagnostic device according to claim 1 .

3. an imaging unit that rotates around the subject to image the subject from a plurality of different positions including a predetermined reference position, and generates a plurality of raw image data including information indicating relative positions with respect to the predetermined reference position; a correction unit that corrects information indicating the relative position included in the original image data according to a deviation between an orientation of the subject and a direction from the subject to the predetermined reference position; a reconstruction unit that generates a reconstructed image by reconstructing the plurality of pieces of original image data generated by the imaging unit based on the relative positions corrected by the correction unit; and A medical imaging diagnostic device comprising:

4. The information indicating the relative position is a view number that increases according to the rotation angle of the imaging unit. The medical image diagnostic apparatus according to claim 3 .

5. The original image data includes the view number and the value of the X-ray intensity. The medical image diagnostic apparatus according to claim 4.

6. The imaging unit An X-ray tube; an X-ray detector that detects X-rays irradiated by the X-ray tube and passed through a subject; a gantry on which the X-ray tube and the X-ray detector are respectively installed at positions facing each other and which has a rotation mechanism that rotates around the subject; 3. The medical image diagnostic apparatus according to claim 1, comprising:

7. a computer of a medical image diagnostic apparatus including an imaging unit that rotates around a subject, images the subject from a plurality of different positions including a predetermined reference position, and generates a plurality of raw image data including information indicating the predetermined reference position; The reference position is corrected in accordance with a deviation between the orientation of the subject and a direction from the subject to the predetermined reference position, the imaging unit is caused to image the subject using the corrected reference position as a reference, and a reconstructed image is generated by reconstructing the plurality of original image data generated by the imaging unit based on the corrected reference position. A method for controlling a medical imaging diagnostic device.

8. a computer of a medical image diagnostic apparatus including an imaging unit that rotates around a subject, images the subject from a plurality of different positions including a predetermined reference position, and generates a plurality of raw image data including information indicating relative positions with respect to the predetermined reference position; Correcting information indicating the relative position included in the original image data according to a deviation between the orientation of the subject and a direction from the subject to the predetermined reference position, and generating a reconstructed image by reconstructing the plurality of original image data generated by the imaging unit based on the corrected relative positions corrected by the correction unit. A method for controlling a medical imaging diagnostic device.

9. a computer of a medical image diagnostic apparatus including an imaging unit that rotates around a subject to image the subject from a plurality of different positions including a predetermined reference position, and generates a plurality of raw image data including information indicating the predetermined reference position; Correcting the reference position in accordance with a deviation between the orientation of the subject and a direction from the subject to the predetermined reference position, causing the imaging unit to image the subject using the corrected reference position as a reference, and generating a reconstructed image by reconstructing the plurality of original image data generated by the imaging unit based on the corrected reference position. program.

10. a computer of a medical image diagnostic apparatus including an imaging unit that rotates around a subject to image the subject from a plurality of different positions including a predetermined reference position, and generates a plurality of raw image data including information indicating relative positions with respect to the predetermined reference position; Correcting information indicating the relative position included in the original image data according to a deviation between the orientation of the subject and a direction from the subject to the predetermined reference position, and generating a reconstructed image by reconstructing the plurality of original image data generated by the imaging unit based on the corrected relative positions corrected by the correction unit. program.

Images