X-ray CT device

Abstract

An X-ray CT device according to an embodiment includes an X-ray tube, an X-ray detector, a scanner, a stand, an acquisition unit, a generation unit, and a display control unit. The X-ray tube irradiates a subject with X-rays. The X-ray detector detects X-rays that pass through the subject. The scanner accommodates the X-ray tube and the X-ray detector, and has an opening into which the subject in a standing or sitting position is inserted. The acquisition unit acquires outer shape information representing the outer shape of the subject and first identification information for identifying an imaging site of the subject. The generation unit generates assistance information representing at least one among the type and arrangement of a support tool for the subject on the basis of the outer shape information, the first identification information, and a space that can be imaged by the scanner. The display control unit displays the assistance information.

Description

X-ray CT device

[0001] The embodiments disclosed in this specification and the drawings relate to an X-ray CT apparatus.

[0002] Some X-ray CT scanners are capable of performing imaging in either a standing or sitting position. In these types of imaging, the scanner is moved vertically to perform imaging, which limits the available imaging space compared to X-ray CT scanners that perform imaging in a supine position because the scanner interferes with the floor. If the subject's imaging area is not included in the available imaging space, a support is used to correct the subject's position. However, because it is difficult for users to intuitively recognize the available imaging space, it is difficult for users to determine which support to use to correct the subject's position.

[0003] JP 2020-192440 A

[0004] One of the problems to be solved by the embodiments disclosed in this specification and the drawings is to assist in the positioning of a support device for a subject during CT imaging in a standing and / or sitting position. However, the problems to be solved by the embodiments disclosed in this specification and the drawings are 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.

[0005] An X-ray CT apparatus according to an embodiment includes an X-ray tube, an X-ray detector, a scanner, a stand, an acquisition unit, a generation unit, and a display control unit. The X-ray tube irradiates a subject with X-rays. The X-ray detector detects X-rays that have passed through the subject. The scanner houses the X-ray tube and the X-ray detector and has an opening into which a subject in a standing or sitting position is inserted. The acquisition unit acquires external shape information that represents the external shape of the subject and first identification information that identifies the region of the subject to be imaged. The generation unit generates support information that represents at least one of the type and arrangement of a support tool for the subject based on the external shape information, the first identification information, and a space that can be imaged by the scanner. The display control unit displays the support information.

[0006] FIG. 1 is a diagram showing an example of the configuration of an X-ray CT system according to the first embodiment. FIG. 2 is a diagram showing a space where imaging can be performed by the X-ray CT system according to the first embodiment. FIG. 3 is a perspective view showing an example of installation of the X-ray CT system according to the first embodiment. FIG. 4 is a diagram schematically showing a flow of generating support information according to the first embodiment. FIG. 5 is a diagram showing an example of an optical image of a subject as external shape information according to the first embodiment. FIG. 6 is a diagram showing an example of a model for determining the type and arrangement of a support tool. FIG. 7 is a diagram showing a first display screen according to the first embodiment. FIG. 8 is a diagram showing a second display screen according to the first embodiment. FIG. 9 is a diagram showing a third display screen according to the first embodiment. FIG. 10 is another perspective view showing an example of installation of the X-ray CT system according to the first embodiment. FIG. 11 is a diagram showing a fourth display screen according to the first embodiment. FIG. 12 is a diagram showing an example of the configuration of an X-ray CT system according to the second embodiment. FIG. 13 is a diagram schematically showing a flow of generating support information according to the fourth embodiment. FIG. 14 is a diagram showing a first display screen according to the fourth embodiment. FIG. 15 is a diagram showing a second display screen according to the fourth embodiment. FIG. 16 is a diagram showing a third display screen according to the fourth embodiment.

[0007] First Embodiment Hereinafter, an embodiment of an X-ray CT apparatus will be described in detail with reference to the drawings.

[0008] 1 is a diagram showing the configuration of an X-ray CT apparatus 1 according to the first embodiment. The X-ray CT apparatus 1 irradiates a subject with X-rays from an X-ray tube 17 and detects the irradiated X-rays with an X-ray detector 19. The X-ray CT apparatus 1 generates a CT image of the subject based on the output from the X-ray detector 19.

[0009] As shown in FIG. 1 , the X-ray CT apparatus 1 includes a gantry 10 and a console 40. For example, the gantry 10 is installed in an examination room, and the console 40 is installed in an operation room adjacent to the examination room. The gantry 10 and the console 40 are connected to each other by wire or wirelessly so that they can communicate with each other. The gantry 10 is equipped with a mechanism for performing X-ray computed tomography (hereinafter referred to as CT) on a subject in a supine, standing, or sitting position. The console 40 is a computer that controls the gantry 10. Note that the X-ray CT apparatus 1 can also be used in a sitting position instead of a standing position.

[0010] As shown in Fig. 1, the gantry 10 has a scanner 11 and a stand (support) 13. The scanner 11 performs X-ray CT imaging. The scanner 11 is a substantially cylindrical structure having an opening (bore) 15. The scanner 11 houses an X-ray tube 17, an X-ray detector 19, a high-voltage generator 31, and a data acquisition system (DAS) 33, which are arranged to face each other across the bore 15.

[0011] More specifically, the scanner 11 further includes a main frame (not shown) made of a metal such as aluminum, and a rotating frame 21 rotatably supported by the main frame around a central axis A1 via bearings or the like. An annular electrode (not shown) is provided at the contact portion of the main frame with the rotating frame 21. A conductive slider (not shown) is attached to the contact portion of the main frame so as to make sliding contact with the annular electrode. The rotating frame 21 is a metal frame made of a metal such as aluminum and has an annular shape, and, for example, an X-ray tube 17 and an X-ray detector 19 are attached to the rotating frame 21.

[0012] The rotating frame 21 receives power from a rotation drive device (not shown) and rotates at a constant angular velocity around the central axis A1 of the bore 15. The rotation drive device generates power for rotating the rotating frame 21 under control of the gantry control device 23. The rotation drive device is realized by a motor such as a direct drive motor or a servo motor, for example.

[0013] The support 13 is a base that supports the scanner 11 at a distance from the floor surface. The support 13 has a columnar shape, such as a cylindrical or rectangular columnar shape. The support 13 is attached to, for example, the side of the scanner 11. To perform CT imaging of a subject in a standing or sitting position, the support 13 supports the scanner 11 so that the scanner 11 can slide vertically relative to the floor surface in a position where the central axis A1 of the bore 15 is maintained perpendicular to the floor surface. The floor surface is an example of a surface on which the support 13 is placed. The floor surface may also be a surface on which the soles of the feet of a subject in a standing or sitting position are placed, or a surface on which a support tool, described below, is placed.

[0014] Typically, the support pillars 13 are provided on both sides of the scanner 11. However, this embodiment is not limited to this. For example, one support pillar 13 may be connected to only one of the two sides of the scanner 11. Also, although the support pillars 13 have a columnar shape, this embodiment is not limited to this. For example, the support pillars 13 may have any shape, such as a U-shape, as long as they can support at least one side of the scanner 11.

[0015] Note that the support column 13 does not need to fix the scanner 11 so that the central axis A1 is perpendicular to the floor surface. That is, the support column 13 may be configured to support the scanner 11 rotatably about a horizontal axis (hereinafter referred to as the tilt axis) parallel to the floor surface. In this case, the support column 13 and the scanner 11 are preferably connected via a bearing or the like so that the scanner 11 can rotate about the tilt axis. This makes it possible to perform CT imaging of a subject in a standing position (standing position imaging), CT imaging of a subject in a sitting position (sitting position imaging), and CT imaging of a subject in a supine position (supine position imaging) using a single gantry 10.

[0016] As shown in FIG. 1 , the support column 13 houses a drive device (hereinafter referred to as the support column drive device) 25 for sliding the scanner 11 in the vertical direction. The support column drive device 25 generates power for sliding the scanner 11 in the vertical direction under control of the scanner control circuit 23. Specifically, the support column drive device 25 generates power by driving at a rotation speed corresponding to the duty ratio, etc., of a drive signal from the scanner control circuit 23. The support column 13 receives power from the support column drive device 25 and slides the scanner 11 in the vertical direction relative to the support column 13. The support column drive device 25 is realized by a motor such as a servo motor. The imaging space of the X-ray CT device 1 is determined by the range in which the scanner 11 can slide and the inner diameter of the bore 15.

[0017] FIG. 2 is a diagram showing a space 20 that can be photographed by the X-ray CT device 1. As shown in FIG. 2, the photographable space 20 is, for example, the range from the photographable cross section at the upper limit height of the scanner 11 to the photographable cross section at the lower limit height. The X-ray CT device 1 can perform CT imaging of a region of a subject included in the photographable space 20. For example, the vertical length of the photographable space 20 is determined by the slidable distance of the scanner 11. The horizontal length of the photographable space 20 is determined by the inner diameter of the bore 15. However, the photographable space 20 is not limited to the specifications imposed by the mechanical constraints of the scanner 11. The dimensions of the photographable space 20 shown in FIG. 2 are maximum values, and the vertical length may be set shorter than the slidable distance for safety reasons, and the horizontal length may be set shorter than the inner diameter of the bore due to influences such as image quality. The photographable range in CT imaging is a spatial range set to accommodate the region to be photographed in the CT imaging (photographic region), and is a part of the photographable space 20.

[0018] As shown in Fig. 1, the X-ray tube 17 generates X-rays when a high voltage is applied from a high-voltage generator 31. The high-voltage generator 31 is attached to, for example, the rotating frame 21. The high-voltage generator 31 generates a high voltage to be applied to the X-ray tube 17 from power supplied from a power supply unit (not shown) of the scanner 11 via an annular electrode, under the control of the gantry control unit 23. The high-voltage generator 31 and the X-ray tube 17 are connected via a high-voltage cable (not shown). The high voltage generated by the high-voltage generator 31 is applied to the X-ray tube 17 via the high-voltage cable.

[0019] The X-ray detector 19 detects X-rays generated by the X-ray tube 17 and transmitted through the subject. The X-ray detector 19 is equipped with multiple X-ray detection elements (not shown) arranged on a two-dimensional curved surface defined by a channel direction and a row direction. Here, the row direction is defined as a direction parallel to the Z axis, and the channel direction is defined as a direction along an arc perpendicular to the row direction. Each X-ray detection element detects X-rays from the X-ray tube 17 and converts them into an electrical signal having a peak value corresponding to the intensity of the detected X-rays. Each X-ray detection element includes, for example, a scintillator and a photoelectric conversion element. The scintillator generates fluorescence upon receiving X-rays. The photoelectric conversion element converts the generated fluorescence into a charge pulse. The charge pulse has a peak value corresponding to the intensity of the X-rays. Specifically, the photoelectric conversion element may be a circuit element, such as a photomultiplier tube or a photodiode, that converts fluorescence into an electrical signal. The X-ray detector 19 according to this embodiment is not limited to an indirect conversion type detector that converts X-rays into fluorescence and then converts them into an electrical signal, but may be a direct conversion type detector that directly converts X-rays into an electrical signal.

[0020] The DAS 33 collects digital data indicating the intensity of X-rays attenuated by the subject for each view. The DAS 33 is connected to the X-ray detector 19 in the scanner 11, for example. The integration circuit integrates electrical signals from the X-ray detection elements over a predetermined view period to generate an integrated signal. The A / D converter A / D converts the generated integrated signal to generate digital data having data values ​​corresponding to the peak values ​​of the integrated signal. The converted digital data is called projection data. The projection data is a set of digital values ​​of X-ray dose identified by the channel number and column number of the X-ray detection element that generated it, and a view number indicating the acquired view. The projection data is supplied to the console 40, for example, via a non-contact data transmission device (not shown) housed in the scanner 11.

[0021] The gantry control device 23 controls the column drive device 25, the high-voltage generator 31, the DAS 33, etc. in accordance with commands from the console 40. The gantry control device 23 has, as hardware resources, a processor such as a CPU (Central Processing Unit) and storage devices (memories) such as a ROM (Read Only Memory) and a RAM (Random Access Memory). The scanner drive system is a drive system related to the components of the scanner 11, such as the high-voltage generator 31, the column drive device 25, and the rotation drive device of the rotating frame 21.

[0022] The console 40 has a processing circuit 41, a memory 42, a display 43, an input interface 44, and a communication interface 45. Data communication between the processing circuit 41, the memory 42, the display 43, the input interface 44, and the communication interface 45 is performed via a bus. Note that although the console 40 will be described as being separate from the gantry 10, the gantry 10 may include the console 40 or some of the components of the console 40.

[0023] The memory 42 is a storage device such as a hard disk drive (HDD), a solid state drive (SSD), or an integrated circuit storage device that stores various information. The memory 42 stores, for example, projection data and reconstructed image data. In addition to an HDD or SSD, the memory 42 may be a portable storage medium such as a compact disc (CD), a digital versatile disc (DVD), or a flash memory. The memory 42 may be a drive device that reads and writes various information from and to semiconductor memory elements such as flash memory and RAM. The storage area of ​​the memory 42 may be located within the X-ray CT apparatus 1 or in an external storage device connected via a network. The memory 42 stores a database, which will be described later.

[0024] The display 43 displays various types of information. For example, the display 43 outputs medical images (CT images) generated by the processing circuitry 41, a GUI (Graphical User Interface) for receiving various operations from the user, and the like. Various types of displays can be used as the display 43, as appropriate. For example, a liquid crystal display (LCD), a cathode ray tube (CRT), an organic electroluminescence display (OELD), or a plasma display can be used as the display 43. The display 42 may also be provided on the pedestal 10. The display 43 may be a desktop type or may be configured as a tablet terminal or the like capable of wireless communication with the console 40 main body. The display 43 is an example of a display unit.

[0025] The input interface 44 accepts various input operations from the user, converts the accepted input operations into electrical signals, and outputs the electrical signals to the processing circuit 41. Examples of the input interface 44 that can be used include a mouse, keyboard, trackball, switch, button, joystick, touchpad, and touch panel display, as appropriate. Note that in this embodiment, the input interface 44 is not limited to a device equipped with physical operation components such as a mouse, keyboard, trackball, switch, button, joystick, touchpad, and touch panel display. For example, an electrical signal processing circuit that receives electrical signals corresponding to input operations from an external input device provided separately from the device and outputs the electrical signals to the processing circuit 41 is also included as an example of the input interface 44. The input interface 44 may also be provided on the pedestal 10. The input interface 44 may also be configured as a tablet terminal or the like that is capable of wireless communication with the console 40 main body.

[0026] The communication interface 45 is an interface for data communication between the X-ray CT apparatus 1 and other computers and / or sensors. For example, the communication interface 45 transmits and receives, via a network, external shape information representing the external shape of a subject, first identification information identifying an imaging region of the subject, second identification information identifying the posture of the subject at the time of imaging, and / or imaging protocols between the X-ray CT apparatus 1 and computers such as a PACS (Picture Archiving and Communication System), a HIS (Hospital Information System), a RIS (Radiology Information System), etc. and / or sensors such as optical cameras.

[0027] The speaker 46 is a device that converts an electrical signal (electrical vibration) into sound (physical vibration) and outputs the sound. For example, the speaker 46 outputs sound based on the electrical signal from the processing circuit 41.

[0028] The processing circuitry 41 controls the overall operation of the X-ray CT apparatus 1 in response to electrical signals of input operations output from the input interface 44. For example, the processing circuitry 41 has, as hardware resources, a processor such as a CPU and memories such as ROM and RAM. The processing circuitry 41 executes an imaging control function 411, an acquisition function 412, a generation function 413, an image reconstruction function 414, a display control function 415, and a sound generation function 416, etc., by a processor that executes a program expanded in the memory. Each of the functions 411-416 is not limited to being realized by a single processing circuit. A processing circuit may be configured by combining multiple independent processors, and each processor may execute a program to realize each of the functions 411-416.

[0029] In the imaging control function 411, the processing circuitry 41 issues a command to the gantry control device 23 so that the gantry 10 performs X-ray CT imaging in accordance with the scan conditions. The gantry control device 23 controls the column drive device 25, the high-voltage generator 31, the DAS 33, etc. in accordance with a command from the console 40 so that X-ray CT imaging is performed.

[0030] In the acquisition function 412, the processing circuitry 41 acquires external shape information representing the external shape of the subject and first identification information identifying the imaging region of the subject. As an example, the external shape information is acquired as an optical image capturing the external shape of the subject captured by a sensor such as an optical camera. The processing circuitry 41 acquires the first identification information from the PACS, HIS, and / or RIS via the communication interface 45 as part of an imaging protocol. The processing circuitry 41 may also acquire second identification information identifying the subject's posture during CT imaging via the acquisition function 412. The second identification information may be acquired from the PACS, HIS, and / or RIS via the communication interface 45 as part of an imaging protocol. The second identification information may be acquired by image analysis of an optical image captured during positioning for CT imaging. The optical image captured by the sensor such as an optical camera may be a still image or a video image.

[0031] In the generation function 413, the processing circuitry 41 generates support information indicating the type and / or arrangement of a subject support used to include the imaging region of a subject in a standing or sitting position in the imaging space 20, based on the external shape information, the first identification information, and the space 20 that can be imaged by the scanner. Specifically, the support includes a pole that can be set upright on the floor surface 50, a step that supports the subject's feet, a seat that is detachably attached to the pole and supports the subject's buttocks, and / or a handle that is detachably attached to the pole and supports the subject's hands. The arrangement of the support is a concept that includes, for example, the size, number, and / or position. Note that when the second identification information is acquired, in the generation function 413, the processing circuitry 41 may generate support information based on the external shape information, the first identification information, the space 20 that can be imaged by the scanner, and the second identification information.

[0032] In the image reconstruction function 414, the processing circuitry 41 reconstructs a CT image of the subject based on the projection data output from the DAS 33. The CT image represents the spatial distribution of CT values ​​that evaluate the attenuation coefficient of a material. The processing circuitry 41 converts the CT image into a cross-sectional image of an arbitrary cross section or a rendering image of an arbitrary viewpoint direction. The conversion is performed based on an input operation received from a user via the input interface 43. For example, the processing circuitry 41 performs three-dimensional image processing such as volume rendering, surface volume rendering, image value projection processing, MPR (Multi-Planar Reconstruction) processing, and CPR (Curved MPR) processing on the CT image to generate rendering image data of an arbitrary viewpoint direction. As the image reconstruction algorithm, an existing image reconstruction algorithm such as the FBP (filtered back projection) method or the iterative reconstruction method may be used.

[0033] In the display control function 415, the processing circuitry 41 displays various information related to CT imaging on the display 43.

[0034] In the sound generation function 416, the processing circuitry 41 generates various information related to CT imaging as sound via the speaker 46.

[0035] The X-ray CT apparatus and the support tool according to the first embodiment will be described in detail below.

[0036] FIG. 3 is a perspective view of the X-ray CT apparatus 1 installed in an examination room. As shown in FIG. 3, a pair of support columns 13 are erected on a floor surface 50. The pair of support columns 13 support a scanner 11 so that it can move vertically. Here, the direction perpendicular to the floor surface 50 is referred to as the Z-axis direction, the direction horizontally perpendicular to the Z-axis direction and aligned with the pair of support columns 13 is referred to as the X-axis direction, and the direction horizontally perpendicular to the Z-axis direction and the X-axis direction is referred to as the Y-axis direction. The −Z-axis direction is referred to as downward, the +Z-axis direction as upward, the −Y-axis direction as forward, and the +Y-axis direction as backward. The Z-axis is parallel to the central axis A1 of the scanner 11 during standing position imaging. For example, in the case of standing position imaging, the subject P enters below the scanner 11 from the front. The scanner 11 is supported by the slide mechanism of the support columns 13 so that it can move in the Z-axis direction.

[0037] As shown in Fig. 3, when imaging a subject P in a standing position, a pole 111 is provided to stabilize the posture of the subject P. The pole 111 is a columnar support that can be erected on the floor surface 50. The pole 111 is erected on the floor surface 50 so as to pass through the bore 15. The pole 111 shown in Fig. 3 has a first colored portion 111a representing the space 20 that can be imaged and a second colored portion 111b representing the space other than the space 20 that can be imaged. This can help identify the space 20 that can be imaged in the vertical direction. Note that multiple poles 111 may be provided.

[0038] As shown in FIG. 3 , an optical camera 61 that captures an optical image of the subject P is provided in the examination room. The optical image is used as external shape information of the subject P. The optical camera 61 is installed, for example, on the side, ceiling, and / or bore 15 of the examination room. As shown in FIG. 3 , the number of optical cameras 61 provided in the examination room may be two or more, or may be one. However, it is preferable that at least one optical camera 61 is installed so as to be able to capture an image of the subject P from a horizontal direction. The X-ray CT device 1 may include the optical camera 61 as the input interface 44, or may be connected via the communication interface 45. Note that the X-ray CT device 1 does not necessarily have to include the optical camera 61 if external shape information of the subject P can be acquired by other means.

[0039] 4 is a diagram showing a processing procedure for generating support information according to the first embodiment. As shown in FIG. 4, the processing circuitry 41 acquires, by implementing the acquisition function 412, external shape information, first identification information corresponding to the imaging region of the subject P, and second identification information corresponding to the imaging position of the subject P (step S1). The external shape information may be, for example, an optical image of the subject P captured by the optical camera 61, or a physical model of the subject P calculated based on the external shape of the subject P. The first identification information and the second identification information are acquired from an imaging protocol related to the subject P.

[0040] When step S1 is performed, the processing circuitry 41, by realizing the generation function 413, determines whether the imaging region is included in the imaging-enabled space 20 (step S2). More specifically, the processing circuitry 41 determines whether the imaging region is included in the imaging-enabled space 20 by identifying the imaging region in the contour information based on the contour information and the first identification information. As an example, if the first identification information is an organ such as the lungs or the heart, the chest included in the contour information is identified as the imaging region. As another example, if the first identification information is an organ such as the stomach or the liver, the abdomen included in the contour information is identified as the imaging region. Image analysis or the like is used to determine whether the imaging region in the optical image is included in the imaging-enabled space 20. However, the identification of the imaging-enabled space 20 is not limited to image analysis. The imaging-enabled space 20 may be identified using a predetermined imaging-enabled space 20 calculated based on information about the range of motion of the scanner 11.

[0041] FIG. 5 illustrates an optical image of the subject P and the pole 111 captured by the Y-axis optical camera 61 in FIG. 3 . As shown in FIG. 5 , the pole 111 may have a first colored portion 111a representing the imageable space 20 in the vertical direction and a second colored portion 111b representing the area other than the imageable space 20. As an example, the first colored portion 111a representing the imageable space 20 is colored black, and the second colored portion 111b representing the remaining area is colored gray. By using the different colors of the pole 111 as markers, the imageable space 20 in the vertical direction of the scanner 11 can be easily identified through image analysis. Note that the imaging direction of the optical image is not limited to a direction in which the side of the subject P and the pole 111 are captured. The imaging direction may be any direction in which the subject P and the first colored portion 111a of the pole 111 are captured in the optical image. As an example, the imaging direction may be one in which the pole 111 and the back of the subject P leaning against the pole 111 are captured in the optical image. The coloring of the first colored portion 111a and the second colored portion 111b of the pole 111 is not limited to black and gray. The coloring of the first colored portion 111a and the second colored portion 111b of the pole 111 may be any color as long as the imageable space 20 can be identified. In addition, if one of the first colored portion or the second colored portion is colored, the other does not have to be colored.

[0042] If the imaging region is included in the imaging-enabled space 20 (step S2: YES), there is no need to correct the position of the subject P using a support tool, and the support information generation process according to the first embodiment ends.

[0043] If the imaging region is not included in the imaging-enabled space 20 (step S2: NO), the processing circuitry 41 generates support information by implementing the generation function 413 (step S3). The support information includes information for supporting the determination of the type and arrangement of supports for correcting the position of the subject so that the imaging region of the subject is included in the imaging-enabled space 20. The arrangement of supports is a concept that includes the size, number, and / or position of the supports. The type and arrangement of supports may be determined using a model described below.

[0044] FIG. 6 is a diagram illustrating an example of the input and output of a model that defines the correspondence between an imaging region, posture, type of support, and support arrangement. As shown in FIG. 6 , first identification information identifying the imaging region of the subject P and second identification information identifying the posture of the subject P at the time of imaging are input to the model. The model outputs the type and / or arrangement of the support corresponding to the input first identification information and second identification information. For example, the type of support is a step, a seat, and / or a handle. The arrangement of the support is the number, size, and / or position. However, the model may output the type and arrangement of the support in response to input of the first identification information, or may output the type of support in response to input of the second identification information. The model may be a machine learning model or a correspondence table (Look Up Table: LUT). The model may be stored in the memory 42. The support information may be generated to correct the vertical position of the imaging region or the horizontal position. However, if multiple decisions are possible regarding the placement of the support tool, it is preferable to determine one appropriate placement. The appropriate placement may be, for example, the size of the platform with the lowest or highest height among the multiple decisions. As another example, the lowest height among the placements that satisfies the distance (margin) from the upper or lower limit of the imaging space 20, which is preset by the user, to the imaging region is determined.

[0045] In addition, if the imaging area is not included in the imaging-enabled space 20, the processing circuitry 41 may realize the sound generation function 416 to generate a notification sound via the speaker 46 to notify of an error in the imaging conditions.

[0046] When step S3 is performed, the processing circuitry 41 displays the support information by implementing the display control function 415 (step S4). As an example, the processing circuitry 41 displays a display screen representing the support information on the display 43. However, the processing circuitry 41 may also display a display screen representing the support information on an external display via the communication interface 45. The processing circuitry 41 may generate a display screen including a schematic diagram representing the support information by implementing the generation function 413. For example, the processing circuitry 41 generates a schematic diagram in which an image of a support tool and an optical image of the subject P captured by an optical camera are superimposed. Note that the generated display screen is not limited to a schematic diagram. The processing circuitry 41 may also generate a display screen including a character string representing the support information.

[0047] When step S4 is performed, the generation of support information according to the first embodiment is completed.

[0048] The support information generation process according to the first embodiment will be described in detail below using three specific examples. In the following three specific examples, an optical image is used as the external shape information of the subject P.

[0049] As a first specific example, a case will be described in which the first identification information, that is, the information identifying the imaging region, is the lower leg, and the second identification information, that is, the information identifying the subject's posture, is the standing position.

[0050] 5, in step S1, an optical image is acquired via an optical camera 61 installed in an examination room. The acquired optical image has as its subject a subject P leaning against a pole 111 in an upright position. The pole 111 may have a first colored portion 111a representing the imageable space 20 and a second colored portion 111b representing the space other than the imageable space 20. The first identification information and the second identification information are acquired as part of an imaging protocol.

[0051] In step S2, it is determined whether the imaging region is included in the imageable space 20. As a specific processing flow, the processing circuitry 41 extracts the first colored portion 111a of the pole 111 from the optical image and identifies the imageable space 20 from the first colored portion 111a of the pole 111. The processing circuitry 41 may extract the first colored portion 111a of the pole 111 using segmentation. The processing circuitry 41 may identify at least the imageable space 20 in the vertical direction from the first colored portion 111a of the pole 111. Furthermore, the processing circuitry 41 may identify the imaging region appearing in the optical image based on the subject P appearing in the optical image and the first identification information. The imaging region appearing in the optical image may be identified by using segmentation. Whether the imaging region is included in the imageable space 20 is determined based on the imaging region identified in the optical image and the imageable space 20. Hereinafter, it is assumed that the imaging region is determined not to be included in the imageable space 20.

[0052] In step S3, the height of the platform is determined as support information. More specifically, the processing circuitry 41 determines one platform from among multiple platforms having heights of approximately 100 mm to 300 mm. However, if multiple platforms are available, the platform used as support information may be determined to be the lowest platform or the highest platform. If the lowest platform is determined, it is possible to provide a sense of security to the subject. Furthermore, if the highest platform is determined, it is possible to reduce the possibility of the scanner 11 interfering with the floor surface 50. Furthermore, since the travel distance of the scanner 11 is reduced, it is possible to shorten the examination time. Hereinafter, it is assumed that the platform height is determined to be 200 mm.

[0053] In step S4, the support information is displayed. FIG. 7 is a diagram illustrating a display screen I1 displaying the support information. Based on the support information, the display screen I1 in FIG. 7 displays a schematic diagram showing a sample of the subject P and support arrangement. The schematic diagram displays the subject P and the support. The subject P and the support may be displayed as an illustration such as a schematic, an optical image captured by an optical camera, or a combination of an illustration and an optical image. As an example, the subject P in FIG. 7 is a schematic based on an optical image captured by an optical camera, and the support is displayed using an illustration. The schematic diagram displays a character string I11 indicating the arrangement of the support, a vertical range I12, and an imaging region I13. The character "D" in the character string I11 indicates that a step 112 has been selected as the type of support. The character string "20" in the character string I11 indicates that a height of 20 cm has been selected as the size of the support. The vertical range I12 indicates the space 20 that can be photographed in the vertical direction, which is identified based on the first colored portion 111a of the pole 111. The photographed portion I13 indicates the photographed portion that is identified based on the first identification information. By displaying the vertical range I12 and the photographed portion I13, the user can confirm that the photographed portion is included in the space 20 that can be photographed when the support tool is positioned according to the schematic diagram.

[0054] As a second specific example, a case where the first identification information, that is, the imaging region is the lumbar region and the second identification information, that is, the posture of the subject is in a sitting position, will be described.

[0055] In step S1, an optical image is acquired via an optical camera 61 installed in the examination room. The acquired optical image is of a subject P in a seated position leaning against a pole 111. For example, the subject P is seated on a seat supported by three poles 111. The seat is detachably provided at multiple heights on the pole 111 and has a mechanism for adjusting the height. Specifically, the pole 111 has multiple holes at predetermined intervals. The seat is fixed by pinning or screwing into the holes in the pole 111. The holes may be marked to distinguish them from holes at other heights.

[0056] In step S2, it is determined whether or not the imaging region is included in the imaging-enabled space by the same process as in the first specific example.

[0057] In step S3, the height of the seat is determined as support information. If the subject P's feet do not touch the floor 50 when sitting on the seat, the processing circuitry 41 may further determine a step for supporting the subject P's feet. This can reduce the subject P's anxiety. Hereinafter, it is assumed that the height of the seat is determined to be 750 mm and the height of the step is determined to be 300 mm.

[0058] In step S4, the support information is displayed. FIG. 8 is a diagram illustrating an example of a display screen I2 displaying the support information. Based on the support information, the display screen I2 in FIG. 8 displays a schematic diagram showing a sample of the subject P and the support device. The schematic diagram displays the subject P and the support device. As an example, the subject P in FIG. 8 is a schema based on an optical image captured by an optical camera, and the support device is displayed using a previously captured optical image. The schematic diagram displays character strings I21 and I22 indicating the support device arrangement, a vertical range I23, an imaging region I24, and information I25 about the subject. The "D" in the character string I21 indicates that the step 112 has been selected as the type of support device. The "30" in the character string I21 indicates that a height of 30 cm has been selected as the size of the support device. The "S" in the character string I22 indicates that the seat 113 has been selected as the type of support device. However, there may be multiple types of seats, each with a different shape. In this case, it is preferable to assign a character string I22 identifiable as "S," such as "s" or "Sa," to each of the multiple types. The "75" in the character string I22 indicates that a height of 75 cm has been selected as the height at which the seat 113 is to be installed. However, the character string I22 may also display a mark to guide the user to install the seat 113 at the selected height on the pole 111. Alternatively, the character string "S75" may be inscribed on the pole 111 as a mark. The character string I22 allows the user to easily determine the height at which the seat 113 should be installed on the pole 111. The vertical range I23 indicates the vertically imageable space 20 identified based on the first colored portion 111a of the pole 111. The imaging region I24 represents the imaging region identified based on the first identification information. The subject-related information I25 represents the subject's ID number, date of birth, and biometric information. In FIG. 8 , the biometric information displays the subject's current heart rate and electrocardiogram. The subject information I25 is not limited to an ID number, date of birth, and biological information. For example, information such as the subject's height and weight may be displayed as the subject information, or biological information such as body temperature and blood pressure may be displayed. Alternatively, the subject information may be at least one of the ID number, date of birth, biological information, height, and weight.By displaying the information I25 about the subject, the user can easily manage the subject.

[0059] As a third specific example, a case where the first identification information, that is, the imaging region is the lungs, and the second identification information, that is, the subject's posture is upright, will be described.

[0060] In step S1, an optical image is acquired via the optical camera 61 provided in the examination room. The acquired optical image has the subject P leaning against the pole 111 in an upright position as its subject.

[0061] In step S2, it is determined whether or not the imaging region is included in the imaging-enabled space by the same process as in the first specific example.

[0062] In step S3, the height of the handle is determined as support information. When the examination site is the lungs, noise may occur in the CT image when the subject's arm is positioned at the same height as the lungs. For this reason, a handle may be provided to keep the subject's arm elevated so that it is not positioned at the same height as the lungs. The handle may be detachably attached to the pole 111 using a mechanism similar to that of the seat in the second specific example. The height of the handle may be determined, for example, by identifying the subject's arm in the optical image by segmentation, so that the subject's elbow is not included in the imaging space 20. Hereinafter, it is assumed that the height of the handle is determined to be 180 cm. In addition to the use of the handle, the use of a step 112 may also be determined.

[0063] In step S4, the support information is displayed. FIG. 9 is a diagram illustrating a display screen I3 displaying the support information. Based on the support information, the display screen I3 in FIG. 9 displays a schematic diagram showing a sample of the subject P and the support device. The schematic diagram displays the subject P and the support device. As an example, the subject P in FIG. 9 is an optical image captured by an optical camera, and the support device is displayed using a previously captured optical image. The schematic diagram displays a character string I31 indicating the placement of the support device, a vertical range I32, and an imaging region I33. The "H" in the character string I31 indicates that the handle 114 has been selected as the type of support device. The "180" in the character string I31 indicates that a height of 180 cm has been selected as the position of the support device. However, the character string I31 may also display a mark for the user to place the pole 111 at the selected height. Alternatively, a character string such as "H180" may be written on the pole 111 as a mark. The character string I31 allows the user to easily understand the height at which the handle 114 should be installed on the pole 111. The vertical range I32 indicates the vertically photographable space 20 identified based on the first colored portion 111a of the pole 111. The photographed region I33 indicates the photographed region identified based on the first identification information.

[0064] By implementing the display control function 415, the processing circuitry 41 displays a display screen notifying an error if the imaging region is not included in the imaging-enabled space 20. Support information indicating the position of the seat 113 and / or the handle 114 may be displayed by illuminating the pole 111 with light from a projector used for positioning. In this case, it is preferable that the projector has a tilt function that allows the light to be projected onto the pole 111. Furthermore, support information may be generated to correct the horizontal position. This helps positioning of the support so that the subject P and the scanner 11 do not interfere with each other, thereby improving the safety of the X-ray CT device 1.

[0065] FIG. 10 is another perspective view of the X-ray CT device 1 installed in the examination room. A guide 115 indicating the horizontally imageable space 20 is installed on the floor 50. The guide 115 is preferably provided at the boundary between the horizontally imageable space 20 and the rest of the area. The guide 115 preferably has an opening in the Y-axis direction so that the first colored portion 111a and the second colored portion 111b of the pole 111 can be seen from a camera 61 installed on the side of the examination room. The guide 115 may also be made of a transparent or translucent material so that the first colored portion 111a and the second colored portion 111b of the pole 111 can be seen. This can assist in identifying the horizontally imageable space 20.

[0066] FIG. 11 is a diagram illustrating a display screen I4 displaying support information. The display screen I4 in FIG. 11 displays a schematic diagram showing a sample of the subject P and support arrangement based on the support information. The schematic diagram displays the subject P and the support. The schematic diagram also displays a character string I41 indicating the arrangement of the support and a horizontal range I42. The character string "R" in the character string I41 displayed in FIG. 11 indicates that the pole 111 has been selected as the type of support. The character string "30" in the character string I41 indicates that the pole 111 has been selected to be erected at a position 30 cm from the center of the horizontally photographable space 20. If the position at which the pole 111 is to be erected cannot be determined solely by the distance from the center of the horizontally photographable space 20, it is preferable to write a character string I41 corresponding to the erection position, such as "R1" or "Ra," at each erection position. The floor surface 50 may have a hole or a base for erecting the pole 111. The holes and bases may each have a different character string inscribed thereon, with one of the different character strings preferably being the same as character string I41. This allows the user to easily determine the position where pole 111 should be installed. Horizontal range I42 indicates the horizontally imageable space 20 identified based on the position of guide 115. Using guide 115 as a landmark, it is possible to easily identify the horizontally imageable space 20 of scanner 11 through image analysis.

[0067] (Summary) The first embodiment will be compared with a comparative example in which the user determines the type and placement of the support. In the comparative example, the user reads scales printed on the support columns and determines and places the support necessary to include the imaging region within the imaging space, thereby correcting the subject's position. However, in a system in which the scanner slides vertically for upright and / or sitting position imaging, the subject is blocked by the scanner from the user's perspective, such as a doctor or technician. Therefore, unless the user peers into the bore, it is difficult for the user to visually confirm the positional relationship between the imaging space and the imaging region of the subject. Furthermore, the procedure for the user to read the scales and determine the optimal type and placement of the support for the imaging region and posture of the subject is cumbersome. In contrast to the comparative example, the present embodiment makes it possible to automatically determine the optimal type and placement of the support so that the imaging region is included within the imaging space. Furthermore, the user can easily confirm the determined type and placement of the support on the display screen. Furthermore, the first colored portion of the pole allows the user to easily visually check the positional relationship between the space that can be photographed and the part of the subject P that is to be photographed, thereby improving the workflow of CT photography and reducing stress on the subject.

[0068] Second Embodiment In the X-ray CT device according to the first embodiment, the outer shape information is an optical image. However, in the X-ray CT device according to the second embodiment, the outer shape information is a physical model of the subject P calculated based on the outer shape of the subject. The X-ray CT device according to the second embodiment will be described below. However, components having the same functions as those in the first embodiment will be given the same reference numerals and will be described only when necessary.

[0069] FIG. 12 is a diagram showing the configuration of an X-ray CT apparatus 1 according to the second embodiment.

[0070] The processing circuitry 41 controls the overall operation of the X-ray CT apparatus 1 in response to electrical signals of input operations output from the input interface 44. For example, the processing circuitry 41 has, as hardware resources, a processor such as a CPU and memories such as ROM and RAM. The processing circuitry 41 executes an imaging control function 411, an acquisition function 412, a generation function 413, an image reconstruction function 414, a display control function 415, a calculation function 417, and the like, by a processor that executes a program expanded in the memory. Each of the functions 411-415 and 417 does not necessarily have to be realized by a single processing circuit. A processing circuit may be configured by combining multiple independent processors, and each processor may execute a program to realize each of the functions 411-415 and 417.

[0071] In the generation function 413, the processing circuitry 41 generates support information based on the first identification information and the positional deviation amount.

[0072] In the calculation function 417, the processing circuitry 41 calculates the amount of positional deviation of the subject P from the imageable space 20. Furthermore, the processing circuitry 41 may calculate a physical model of the subject P as external shape information based on the external shape of the subject P.

[0073] More specifically, the processing circuitry 41 calculates a physical model of the subject P that estimates the physique of the subject P based on the height, weight, body mass index (BMI), body fat percentage, and / or gender of the subject P. The height, weight, BMI, body fat percentage, and / or gender of the subject P may be acquired, for example, from an imaging protocol, or from an HIS or RIS. Using the calculated physical model of the subject P, the processing circuitry 41 performs a simulation in which the subject P, in a standing or sitting position, is placed in an imaging space, thereby generating support information that suggests the type and / or placement of a support tool for including the imaging region of the subject P in the imaging space.

[0074] Specifically, in a virtual image processing space, a physical model of the subject P, oriented based on the second identification information, is arranged within the passage area of ​​the bore of the scanner 11. For example, in the virtual image processing space, a physical model of the subject P, a physical model of the scanner 11, a physical model of a support, and a physical model of the floor are arranged to reproduce CT imaging. A simulation is performed to determine whether the imaging region of the physical model of the subject P based on the first identification information is included in the imaging space. This allows the determination of whether the imaging region is included in the imaging space in step S2 of FIG. 4. If it is determined that the imaging region is not included in the imaging space, the amount of positional deviation of the physical model of the subject P is calculated. For example, the amount of positional deviation is the distance from the sole of the foot or the waist required for the imaging region of the physical model of the subject P to be included in the imaging space. Based on the calculated amount of positional deviation, the processing circuitry 41 determines the type, size, number, and / or position of the support for correcting the position of the physical model of the subject P. The support information may be displayed as a three-dimensional diagram representing a physical model of the subject P, a physical model of the scanner 11, and a physical model of the support device, which are arranged in a virtual image processing space. By generating the support information using the physical model of the subject P as external shape information, it is possible to generate the support information without placing the subject P in the X-ray CT device 1 to capture an optical image.

[0075] When determining the position of the handle 115, it is preferable that the physical model of the subject P estimates the arm length, shoulder position, elbow position, and / or wrist position in addition to the physique of the subject P. This makes it possible to determine the position of the handle 115 so that the arm position is not at the same height as the imaging region without using optical images. Furthermore, the processing circuitry 41 may simulate the shape of the arm of the physical model of the subject P gripping the handle 115.

[0076] According to the second embodiment, it is possible to generate support information without using an optical image for the external shape information.

[0077] (Third Embodiment) The X-ray CT system 1 according to the first and second embodiments displays support information on the display 43. The X-ray CT system according to the third embodiment has a support column equipped with a display that displays support information. The X-ray CT system according to the third embodiment will be described below. However, components having the same functions as those in the first or second embodiment are designated by the same reference numerals, and will be described only when necessary.

[0078] The support column 13 is provided with a display that displays support information at a position facing outward from approximately the central axis of the bore. The display provided on the support column 13 is an example of a display unit. The processing circuitry 41 may also generate support information viewed from the display direction by implementing the generation function 413. This allows the actual arrangement of the subject and support tool to match the support information, allowing the user to easily check the arrangement of the support tool.

[0079] According to the third embodiment, a display is provided on the support column 13, so that a user who performs positioning of a subject in an examination room can check support information.

[0080] (Fourth Embodiment) The X-ray CT apparatus according to the first, second, and third embodiments generates supporting information and displays the generated supporting information. The X-ray CT apparatus according to the fourth embodiment changes the position of a physical model of an object included in the displayed supporting information in accordance with a user's instruction, and generates new supporting information based on the changed position of the physical model of the object. The X-ray CT apparatus according to the fourth embodiment will be described below. However, components having the same functions as those in the first, second, or third embodiment are denoted by the same reference numerals and will be described repeatedly only when necessary. Note that supporting information in which the position of the physical model of the object is changed is referred to as first supporting information. Furthermore, supporting information newly generated based on the changed position of the physical model of the object is referred to as second supporting information.

[0081] The calculation function 417 calculates the amount of positional deviation of the physical model of the subject from the position of the physical model of the subject in the support information including the generated three-dimensional virtual image processing space, in accordance with a user instruction.

[0082] 13 is a diagram showing the processing procedure for generating support information according to the fourth embodiment. Steps S1 to S4 shown in FIG. 13 are the same as the processing shown in the first embodiment, so the processing procedure from step S5 onwards will be described.

[0083] After step S4 is performed, the processing circuitry 41 determines whether or not to confirm the displayed support information (step S5) by implementing the display control function 415. The determination of whether or not to confirm the displayed support information may be made in accordance with a user instruction via the display screen.

[0084] 14 is a diagram illustrating a display screen I5 that displays support information. Display screen I5 in FIG. 14 displays a three-dimensional virtual image processing space showing a sample in which a physical model MP of the subject, a physical model M111 of the pole, and a physical model M112 of the step are arranged based on the support information. The three-dimensional virtual image processing space displays the physical model MP of the subject, the physical model M111 of the pole, the physical model M112 of the step, the physical model M11 of the scanner, and a physical model M50 of the floor. The physical model MP of the subject is, for example, a physical model calculated by the calculation function 417.

[0085] The three-dimensional virtual image processing space displays a character string I51 indicating the placement of the support, a vertical range I52, an imaging region I53, a button I54 for adjusting the position of the subject's physical model MP, and a button I55 for confirming the placement of the support. The letter "D" in the character string I51 indicates that a step has been selected as the type of support. The letter "20" in the character string I51 indicates that a height of 20 cm has been selected as the size of the support. The vertical range I52 indicates the vertically imageable space 20 identified based on the first colored portion 111a of the pole physical model M111. The imaging region I53 represents the imaging region identified based on the first identification information. The button I54 for adjusting the position of the subject's physical model MP is a button that can be selected using the input interface 44, such as a mouse and / or a touch panel. As shown in FIG. 14 , the button I54 for adjusting the position of the subject's physical model MP may display a character string indicating the adjustment of the position of the subject's physical model MP, such as "Adjust placement." The button I55 for confirming the placement of the support tool is a button that can be selected using the input interface 44, such as a mouse and / or a touch panel. As shown in FIG. 14 , the button I55 for confirming the placement of the support tool may display a character string indicating that the placement of the support tool has been confirmed, such as "Placement Confirmed." Using the button I54 for adjusting the position of the physical model MP of the subject and the button I55 for confirming the placement of the support tool, it is possible to determine whether or not to confirm the placement of the support tool in accordance with a user's instructions. When the button I55 for confirming the placement of the support tool is selected, the displayed support information is confirmed. If the placement has been confirmed (step S5: YES), the support information generation process according to the fourth embodiment ends.

[0086] When the button I54 for adjusting the position of the physical model MP of the subject is selected, the display screen I5 enters a mode in which it can accept instructions from the user to adjust the position of the physical model MP of the subject.

[0087] If the placement is not confirmed (step S5: NO), the processing circuitry 41 moves the physical model of the subject included in the first support information in accordance with a user instruction (step S6). The processing circuitry 41 also calculates the amount of positional deviation of the moved physical model of the subject. The amount of positional deviation is, for example, the displacement between the position of the physical model of the subject in the first support information including the generated three-dimensional virtual image processing space and the position of the physical model of the subject after being moved. The processing circuitry 41 calculates the amount of positional deviation based on the amount of movement of the physical model of the subject within the three-dimensional virtual image processing space. The value of the amount of positional deviation may be directly input via a keyboard or the like in accordance with a user instruction.

[0088] FIG. 15 illustrates a display screen I5 that can accept a user's instruction to adjust the position of the physical model MP of the subject. The display screen I5 of FIG. 15 includes a physical model MP of the subject whose position can be adjusted in the three-dimensional virtual image processing space. The physical model MP of the subject whose position can be adjusted is a physical model that can be selected using an input interface 44, such as a mouse and / or a touch panel. As an example, the selected physical model MP of the subject is placed at a position desired by the user by an operation such as drag and drop. As shown in FIG. 15 , the physical model MP of the subject is placed at a position moved vertically upward from the first support information. At this time, the physical model MP of the subject should be placed within a range that does not interfere with the scanner physical model M11 and / or the physical model M50 of the floor. A button I56 for completing the adjustment of the position of the physical model of the subject is newly displayed in the three-dimensional virtual image processing space. The button I56 for completing the adjustment of the position of the physical model of the subject is a button that can be selected using an input interface 44, such as a mouse and / or a touch panel. As shown in FIG. 15 , a button I56 for completing the adjustment of the position of the physical model of the subject may display a text string indicating that the adjustment of the position of the physical model of the subject is complete, such as "Adjustment Complete." When the button I56 for completing the adjustment of the position of the physical model of the subject is selected, the amount of positional deviation is calculated. In FIG. 15 , it is assumed that the processing circuitry 41 calculates the amount of positional deviation to be +15 cm in the vertical direction. By adjusting the position of the physical model of the subject on the display screen in accordance with the user's instructions, the user can intuitively adjust the assistance information. Note that the movement direction of the physical model MP of the subject is not limited to the vertical direction. The physical model MP of the subject can be moved in the vertical and / or horizontal directions.

[0089] When step S6 is performed, the processing circuitry 41, by implementing the generation function 413, newly generates second support information based on the amount of positional deviation calculated in step S6 and the first support information. The processing circuitry 41 generates second support information in which the size and / or position of the support tool is changed according to the arrangement of the support tool in the first support information and the amount of positional deviation calculated in step S6. As an example, if the amount of positional deviation in the first support information presenting a 20 cm step stool is 15 cm, the processing circuitry 41 generates second support information in which a 35 cm step stool is presented. Note that the arrangement of the support tool in the second support information may be selected so as to minimize the error with respect to the amount of positional deviation.

[0090] When step S3 is performed, the processing circuitry 41 displays the second support information generated in step S3 by implementing the display control function 415 (step S4).

[0091] FIG. 16 is a diagram showing a display screen I6 displaying the second support information. The display screen I6 in FIG. 16 displays a three-dimensional virtual image processing space showing a sample in which a physical model MP of the subject and a physical model of the support are arranged based on the second support information. The three-dimensional virtual image processing space displays the physical model MP of the subject and the physical model of the support. The physical model MP of the subject and the physical model of the support are, for example, physical models calculated by the calculation function 417. The three-dimensional virtual image processing space displays a character string I61 indicating the arrangement of the support, a vertical range I62, an imaging region I63, a button I64 for adjusting the position of the physical model MP of the subject, and a button I65 for confirming the arrangement of the support. The character string "D" in the character string I61 indicates that a step stool has been selected as the type of support. The character string "35" in the character string I61 indicates that a height of 35 cm has been selected as the size of the support. The vertical range I62 is the same range as I52 shown in FIGS. 14 and 15. The imaging region I63 is the same as I53 shown in Figures 14 and 15. The button I64 for adjusting the position of the physical model MP of the subject is the same as I54 shown in Figures 14 and 15. The button I65 for confirming the placement of the support tool is the same as I55 shown in Figures 14 and 15.

[0092] According to the fourth embodiment, it is possible to automatically select the placement of the support tool suitable for the position after adjustment in conjunction with the position of the physical model of the subject, which has been adjusted in accordance with instructions from the user.

[0093] According to at least one of the embodiments described above, it is possible to assist in the placement of a support device for a subject in CT imaging in a standing position and / or a sitting position.

[0094] The term "processor" used in the above description refers to circuits such as a CPU, a GPU, an application specific integrated circuit (ASIC), a programmable logic device (e.g., a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), and a field programmable gate array (FPGA)). A processor realizes its functions by reading and executing a program stored in a memory circuit. Note that instead of storing a program in a memory circuit, the processor may be configured so that the program is directly embedded in the circuitry of the processor. In this case, the processor realizes its function by reading and executing a program embedded in the circuit. On the other hand, if the processor is, for example, an ASIC, the program is not stored in a memory circuit, but the function is directly embedded in the processor circuit as a logic circuit. Note that each processor in this embodiment is not limited to being configured as a single circuit, but may be configured as a single processor by combining multiple independent circuits to realize its function. Furthermore, multiple components in FIGS. 1 and 12 may be integrated into a single processor to realize its function.

[0095] Although several embodiments have been described, 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, modifications, and combinations of embodiments 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.

[0096] REFERENCE SIGNS LIST 1 X-ray CT device 10 Platform 11 Scanner 13 Stand (pillar) 15 Opening (bore) 17 X-ray tube 19 X-ray detector 21 Rotating frame 23 Platform control device 25 Pillar drive device 31 High voltage generator 33 Data acquisition circuit (DAS) 40 Console 41 Processing circuit 42 Memory 43 Display 44 Input interface 45 Communication interface 411 Imaging control function 412 Acquisition function 413 Generation function 414 Image reconstruction function 415 Display control function

Claims

1. An X-ray CT device comprising: an X-ray tube that irradiates a subject with X-rays; an X-ray detector that detects the X-rays that have passed through the subject; a scanner that houses the X-ray tube and the X-ray detector and has an opening into which the subject, who is in a standing or sitting position, is inserted; a stand that supports the scanner so that it can move vertically; an acquisition unit that acquires external shape information that represents the external shape of the subject and first identification information that identifies the part of the subject to be imaged; a generation unit that generates support information that represents at least one of the type and arrangement of a support device for the subject, based on the external shape information, the first identification information, and a space that can be imaged by the scanner; and a display control unit that displays the support information.

2. The X-ray CT device of claim 1, wherein the generation unit identifies the imaging area in the external shape information based on the external shape information and the first identification information, determines whether the imaging area is included in the imaging-capable space, and generates the support information if it determines that the imaging area is not included in the imaging-capable space.

3. An X-ray CT device as described in claim 2, further comprising a calculation unit that calculates the amount of positional deviation of the subject from the space that can be photographed, and the generation unit generates the support information based on the first identification information and the amount of positional deviation.

4. An X-ray CT apparatus according to claim 3, wherein the calculation unit calculates a physical model based on the external shape of the subject, and calculates the amount of positional deviation based on a simulation using the physical model.

5. The X-ray CT apparatus according to claim 1, wherein the support information includes the type of the support, and the size, number, and / or position of the support.

6. An X-ray CT apparatus as described in claim 1, wherein the acquisition unit further acquires second identification information that identifies the posture of the subject at the time of imaging, and the generation unit further generates the support information based on the second identification information.

7. An X-ray CT device as described in claim 6, further comprising a storage unit that stores a model that defines the correspondence between the imaging region, the posture, the type of support, and the arrangement of the support, and when the generation unit determines that the imaging region is not included in the imaging-capable space, it inputs the first identification information and the second identification information into the model and determines the type and / or arrangement of the support that corresponds to the first identification information and the second identification information.

8. An X-ray CT apparatus according to claim 1, wherein the external shape information is an optical image of the subject taken by an optical camera.

9. An X-ray CT apparatus according to claim 1, wherein the external shape information is a physical model calculated based on the external shape of the subject.

10. An X-ray CT apparatus as described in claim 1, wherein the support includes a pole that can be set upright on the floor, a step that supports the feet of the subject, a seat that is detachably attached to the pole and supports the buttocks of the subject, and / or a handle that is detachably attached to the pole and supports the hands of the subject.

11. An X-ray CT device as described in claim 8, wherein the optical image is an image of the subject leaning against a pole in an upright position, the pole having a colored portion representing the space that can be photographed, and the generation unit extracts the colored portion from the optical image, identifies the space that can be photographed from the colored portion, identifies the space that can be photographed that appears in the optical image based on the subject that appears in the optical image and the first identification information, and determines the height of a step as the support information.

12. An X-ray CT device as described in claim 8, wherein the optical image is an image of the subject sitting on a seat in a seated position, the seat is detachably attached to a pole, the pole has a colored portion representing the space that can be photographed, and the generation unit extracts the colored portion from the optical image, identifies the space that can be photographed from the colored portion, identifies the space that can be photographed that appears in the optical image based on the subject that appears in the optical image and the first identification information, and determines the height of the seat as the support information.

13. An X-ray CT device as described in claim 8, wherein the optical image is an image of the subject leaning against a pole in an upright position, the pole has a colored portion representing the space that can be photographed, and the generation unit extracts the colored portion from the optical image, identifies the space that can be photographed from the colored portion, identifies the space that can be photographed that appears in the optical image based on the subject that appears in the optical image and the first identification information, and determines the height of a handle that supports the subject's hand as the support information.

14. An X-ray CT device as described in claim 2, further comprising a sound generating unit that generates a notification sound via a speaker to notify of an error in the imaging conditions when the imaging region is not included in the imaging-capable space, and the display control unit displays a display screen to notify of an error when the imaging region is not included in the imaging-capable space.

15. The X-ray CT apparatus according to claim 1, further comprising an optical camera for photographing the subject.

16. An X-ray CT device as described in claim 15, wherein the generation unit generates support information including a schematic diagram showing the type and / or arrangement of the subject and the support tool relative to the imageable space, in which an image of the support tool and an optical image of the subject captured by the optical camera are superimposed.

17. The X-ray CT apparatus according to claim 1, wherein the generating unit generates the support information for correcting the vertical position of the imaging region.

18. An X-ray CT apparatus according to claim 1, wherein said generating unit generates said support information for correcting the horizontal position of said imaging region.

19. The X-ray CT apparatus according to claim 1, wherein the stand further comprises a display for displaying the support information.

20. An X-ray CT device as described in claim 1, wherein the generation unit generates support information representing the type and / or arrangement of a support device for the subject used to include the imaging area of ​​the subject in a standing or sitting position in the imaging space based on the external shape information, the first identification information, and the imaging space available for imaging by the scanner.

Images