X-ray CT scanner and control method

Abstract

To raise awareness of the risk of interference between the camera bed and the mount when changing shooting modes. [Solution] The X-ray CT apparatus according to the embodiment comprises a stand, a patient table, a moving mechanism, and a control unit. The stand has a scanner and a stand. The moving mechanism moves at least one of the stand and the patient table along the direction of movement. The control unit performs one of the following: a first control that tilts the scanner and controls the moving mechanism so that the stand and the patient table move apart, based on a first signal that transitions from a first positional relationship of the stand and the patient table when performing a first imaging using the patient table to a second positional relationship of the stand and the patient table when performing a second imaging without the patient table; and a second control that tilts the scanner and controls the moving mechanism so that the stand and the patient table move closer together, based on receiving a second signal that transitions from the second positional relationship to the first positional relationship.

Description

Technical Field

[0005] ,

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

Background Art

[0002] An X-ray CT (Computed Tomography) apparatus that can be used in both standing and lying positions can be switched between a standing imaging mode in which a subject in a standing position can be imaged by tilting the scanner by 90 degrees (tilting), a sitting imaging mode in which a subject in a sitting position can be imaged, and a lying imaging mode in which a subject in a lying position on a bed can be imaged.

[0003] In such a CT apparatus, when switching from the lying imaging mode to the standing imaging mode or the sitting imaging mode, there is a risk that the bed and the scanner will interfere with each other. For this reason, it is necessary to install the bed away from the scanner so that the bed and the scanner do not interfere with each other. On the other hand, as the distance between the bed and the scanner increases, it becomes necessary to increase the movable range (stroke) of the top plate, and there is a risk that the imaging position accuracy will deteriorate due to the influence of the deflection of the top plate caused by the load of the subject.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] One of the problems to be solved by the embodiments disclosed in this specification and the drawings is to reduce the risk that the bed and the gantry interfere with each other when changing the imaging mode. However, the problems to be solved by the embodiments disclosed in this specification and the drawings are not limited to the above problems. The problems corresponding to the respective effects of the respective configurations shown in the embodiments described later can also be regarded as other problems. [Means for solving the problem]

[0006] The X-ray CT apparatus according to the embodiment comprises a stand, a patient table, a moving mechanism, and a control unit. The stand has a scanner having an imaging system and a stand that tiltably supports the scanner. The patient table has a tabletop on which a subject is placed. The moving mechanism moves at least one of the stand and the patient table along the direction of movement. The control unit performs one of the following: a first control that tilts the scanner and controls the moving mechanism so that the stand and the patient table move apart, based on a first signal that transitions from a first positional relationship of the stand and the patient table when performing a first imaging using the patient table to a second positional relationship of the stand and the patient table when performing a second imaging without the patient table; and a second control that tilts the scanner and controls the moving mechanism so that the stand and the patient table move closer together, based on receiving a second signal that transitions from the second positional relationship to the first positional relationship. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 shows an example of the configuration of an X-ray CT apparatus according to an embodiment. [Figure 2] Figure 2 is a perspective view showing the state of the X-ray CT scanner in supine position mode. [Figure 3] Figure 3 shows an X-ray CT scanner viewed from above in supine position mode. [Figure 4] Figure 4 is a perspective view showing the state of the X-ray CT scanner in standing position mode. [Figure 5] Figure 5 is a perspective view showing the state of the X-ray CT scanner in seated imaging mode. [Figure 6] Figure 6 shows an X-ray CT scanner viewed from above in standing and sitting modes. [Figure 7] Figure 7 is a flowchart illustrating the procedure for the first mode switching process by the X-ray CT apparatus according to the embodiment. [Figure 8]Figure 8 shows the X-ray CT scanner viewed from above when the first mode switching process is initiated. [Figure 9] Figure 9 shows the process of moving the bed from the state shown in Figure 8. [Figure 10] Figure 10 shows the scanner being tilted from the state shown in Figure 9. [Figure 11] Figure 11 is a flowchart illustrating the procedure for the second mode switching process by the X-ray CT apparatus according to the embodiment. [Figure 12] Figure 12 shows the X-ray CT scanner viewed from above when the second mode switching process is initiated. [Figure 13] Figure 13 shows the scanner being tilted from the state shown in Figure 11. [Figure 14] Figure 14 shows the process of moving the bed from the state shown in Figure 12. [Figure 15] Figure 15 is a view from above of an X-ray CT scanner in supine position according to the first modified example. [Figure 16] Figure 16 is a view from above of the X-ray CT scanner in the standing and sitting modes according to the first modified example. [Figure 17] Figure 17 is a view from above of an X-ray CT scanner in supine position according to the third modified example. [Figure 18] Figure 18 is a view from above of the X-ray CT scanner in standing and sitting modes according to the third modified example. [Figure 19] Figure 19 is a perspective view showing the state of the X-ray CT scanner in supine position according to the fourth modified example. [Figure 20] Figure 20 is a perspective view showing the state of the X-ray CT scanner in standing and sitting modes according to the fourth modified example. [Figure 21] Figure 21 is a view from above of an X-ray CT scanner in supine position according to the fifth modified example. [Figure 22]FIG. 22 is a view of the X-ray CT apparatus in the standing imaging mode and the sitting imaging mode according to the fifth modification example, as viewed from above. [Figure 23] FIG. 23 is a view of the X-ray CT apparatus in the lying imaging mode according to the sixth modification example, as viewed from above. [Figure 24] FIG. 24 is a view of the X-ray CT apparatus in the standing imaging mode and the sitting imaging mode according to the sixth modification example, as viewed from above.

Embodiments for Carrying Out the Invention

[0008] Hereinafter, embodiments of the X-ray CT apparatus and the control method will be described in detail with reference to the drawings. In the following embodiments, parts denoted by the same reference numerals perform the same operations, and redundant descriptions will be omitted as appropriate. Hereinafter, one embodiment will be described with reference to the drawings.

[0009] FIG. 1 is a diagram showing a configuration example of an X-ray CT apparatus 1 according to the present embodiment. As shown in FIG. 1, the X-ray CT apparatus 1 includes a gantry 10, a couch 30, and a console 40. In FIG. 1, for convenience of explanation, a plurality of gantries 10 are drawn, but actually, there may be one or a plurality of gantries. The gantry 10 is a scanning device having a configuration for performing X-ray CT imaging on a subject P such as a patient. The couch 3 is a transport device for placing the subject P to be subjected to X-ray CT imaging and positioning the subject P. The console 40 is a computer that controls the gantry 10. For example, the gantry 10 and the couch 30 are installed in a CT examination room, and the console 40 is installed in a control room adjacent to the CT examination room. The gantry 10, the couch 30, and the console 40 are connected to each other by wire or wirelessly so as to be able to communicate with each other. Note that the console 40 does not necessarily have to be installed in the control room. For example, the console 40 may be installed in the same room as the gantry 10 and the couch 30. Also, the console 40 may be incorporated into the gantry 10.

[0010] As shown in Figure 1, the stand 10 includes a scanner 11, an X-ray tube 12, an X-ray detector 13, a rotating frame 14, an X-ray high-voltage device 15, a wedge 16, a collimator 17, a data acquisition system (DAS) 18, an aperture 19, a support column 20, and a control device 21. The scanner 11 is a substantially cylindrical structure with an aperture 19 formed therein. The scanner 11 houses the X-ray tube 12 and the X-ray detector 13, which are arranged to face each other across the aperture 19.

[0011] The scanner 11 and the support column 20 are connected via a tilt mechanism and a lifting mechanism. The support column 20 is an example of a stand that supports the scanner 11 in a tiltable manner via the tilt mechanism. The tilt mechanism is a mechanism that rotates the scanner 11. For the tilt mechanism, a general rotation mechanism such as gears or a conveyor can be used. The lifting mechanism is a mechanism that moves the scanner 11 up and down along the vertical direction. For the lifting mechanism, a general linear motion mechanism such as a rack and pinion mechanism can be used. Here, an example with one support column 20 is shown, but two support columns 20 may be provided. In this case, one support column 20 is placed on each side of the scanner 11, and the scanner 11 is supported in a tiltable manner by the two support columns 20.

[0012] Here, the direction from the central axis of the aperture 19 of the scanner 11 toward the support column 20 is defined as the X-axis direction, and the directions perpendicular to the X-axis direction are defined as the Y-axis direction and the Z-axis direction. The X-axis direction is approximately parallel to the rotation axis of the scanner 11 due to the tilt mechanism (hereinafter referred to as the tilt axis). The Y-axis direction is approximately parallel to the vertical direction and is also called the up and down direction. The Z-axis direction is perpendicular to the X-axis direction and the Y-axis direction. In this embodiment, the Z-axis direction is an example of a direction of movement.

[0013] The X-ray tube 12 irradiates the subject P with X-rays. Specifically, the X-ray tube 12 includes a cathode that generates thermionic electrons, an anode that receives thermionic electrons flying from the cathode and generates X-rays, and a vacuum tube that holds the cathode and anode. The X-ray tube 12 is connected to the X-ray high-voltage device 15 via a high-voltage cable. A tube voltage is applied between the cathode and anode by the X-ray high-voltage device 15. The application of the tube voltage causes thermionic electrons to fly from the cathode to the anode. A tube current flows as thermionic electrons fly from the cathode to the anode. X-rays are generated when thermionic electrons collide with the anode.

[0014] The X-ray detector 13 detects X-rays irradiated from the X-ray tube 12 and passed through the subject P, and outputs an electrical signal corresponding to the detected X-ray dose to the DAS 18. The X-ray detector 13 has a structure in which multiple rows of X-ray detection elements, each row of X-ray detection elements arranged in the channel direction, are arranged in the slice direction (column direction). The X-ray detector 13 is an indirect conversion type detector having, for example, a grid, a scintillator array, and a photosensor array. The scintillator array has multiple scintillators. The scintillators output light with an amount of light corresponding to the incident X-ray dose. The grid is positioned on the X-ray incident surface side of the scintillator array and has an X-ray shielding plate that absorbs scattered X-rays. The grid is sometimes called a collimator (one-dimensional collimator or two-dimensional collimator). The photosensor array converts the amount of light from the scintillators into an electrical signal. For example, a photodiode is used as the photosensor.

[0015] The X-ray detector 13 may also be a photon counting type detector.

[0016] In a photon-counting type detector, the scintillator converts incident X-rays into a number of photons corresponding to the intensity of the incident X-rays. The photosensor array has the function of amplifying the light received from the scintillator and converting it into an electrical signal, generating an output signal (energy signal) with a pulse height corresponding to the energy of the incident X-rays.

[0017] Furthermore, the X-ray detector 13 may be a direct conversion type detector having a semiconductor element that converts incident X-rays into an electrical signal.

[0018] The rotating frame 14 is an annular frame that supports the X-ray tube 12 and the X-ray detector 13 so that they can rotate around the central axis of the aperture 19. Specifically, the rotating frame 14 supports the X-ray tube 12 and the X-ray detector 13 in opposition to each other. In addition to the X-ray tube 12 and the X-ray detector 13, the rotating frame 14 also supports the X-ray high-voltage device 15 and the DAS 18. The rotating frame 14 is supported by a fixed frame (not shown) so that it can rotate around the central axis of the aperture 19. The rotation mechanism includes, for example, a motor that generates rotational driving force and a bearing that transmits this rotational driving force to the rotating frame 14 and causes it to rotate. The motor is provided on the fixed frame, and the bearing is physically connected to the rotating frame 14 and the motor, so that the rotating frame 14 rotates in accordance with the rotational force of the motor. As the rotating frame 14 rotates, the X-ray tube 12 and the X-ray detector 13 rotate around the central axis of the aperture 19. The rotating frame 14 is an example of a rotating part.

[0019] The X-ray high-voltage device 15 includes a high-voltage generator and an X-ray control device. The high-voltage generator has an electrical circuit including a transformer and a rectifier, and generates the high voltage applied to the X-ray tube 12 and the filament current supplied to the X-ray tube 12. The X-ray control device controls the output voltage according to the X-rays irradiated by the X-ray tube 12. The high-voltage generator may be of the transformer type or the inverter type. The X-ray high-voltage device 15 may be installed on the rotating frame 14 or on a fixed frame (not shown) inside the scanner 11.

[0020] The wedge 16 adjusts the dose of X-rays irradiated onto the subject P. Specifically, the wedge 16 attenuates the X-rays so that the dose of X-rays irradiated from the X-ray tube 12 to the subject P has a predetermined distribution. For example, the wedge 16 can be a metal plate such as aluminum, such as a wedge filter or a bow-tie filter.

[0021] The collimator 17 limits the irradiation range of X-rays that have passed through the wedge 16. The collimator 17 slidably supports multiple lead plates that shield the X-rays and adjusts the shape of the slit formed by the multiple lead plates. The collimator 17 is sometimes called an X-ray diaphragm.

[0022] The DAS18 reads an electrical signal from the X-ray detector 13 corresponding to the X-ray dose detected by the X-ray detector 13. The DAS18 amplifies the read electrical signal and integrates it over the viewing period to collect detection data having a digital value corresponding to the X-ray dose over the viewing period. The detection data is also called projection data. The DAS18 is implemented, for example, by an application-specific integrated circuit (ASIC) equipped with circuit elements capable of generating projection data. The projection data is transmitted to the console 40 via a non-contact data transmission device or the like.

[0023] The rotating frame 14 and the fixed frame are each provided with either a non-contact or contact-type communication circuit, and these communication circuits enable communication between the unit supported by the rotating frame 14 and the fixed frame or external devices of the scanner 11. For example, if optical communication is used as the non-contact communication method, the detection data generated by the DAS 18 is transmitted via optical communication from a transmitter with a light-emitting diode (LED) provided on the rotating frame 14 to a receiver with a photodiode provided on the fixed frame of the scanner 11, and then transferred from the fixed frame to the console 40 by the transmitter. In addition to the above, other non-contact data transmission methods such as capacitive coupling and radio wave methods may also be used as communication methods, as well as contact-type data transmission methods using slip rings and electrode brushes.

[0024] The control device 21 controls the X-ray high-voltage device 15 and DAS 18 to perform X-ray CT imaging according to the imaging control function 442 of the processing circuit 44 of the console 40. The control device 21 has a processing circuit having a Central Processing Unit (CPU) or Micro Processing Unit (MPU), etc., and a drive mechanism such as a motor and actuator. The processing circuit has a processor such as a CPU and memory such as Read Only Memory (ROM) or Random Access Memory (RAM) as hardware resources. The control device 21 performs various functions using the processor that executes the program loaded into memory. Note that the various functions are not limited to being realized by a single processing circuit. Multiple independent processors may be combined to form a processing circuit, and each processor may execute a program to realize each function. Furthermore, the control device 21 may be realized by an ASIC or a Field Programmable Gate Array (FPGA). Furthermore, the control device 21 may be implemented using other complex programmable logic devices (CPLDs) or simple programmable logic devices (SPLDs).

[0025] Furthermore, the control device 21 has the function of controlling the operation of the scanner 11 and the bed 30 by receiving input signals from the input interface 43 (described later) and control signals from the processing circuit 44. The input interface 43 is attached to the console 40 or the scanner 11, for example. For example, the control device 21 controls the rotation of the rotating frame 14, the tilt of the scanner 11, and the operation of the bed 30 and the top plate 33. The control device 21 may be provided on the scanner 11 or on the console 40.

[0026] The bed 30 comprises a base 31, a support frame 32, a top plate 33, and a bed drive device 34. The base 31 is installed on the floor. The base 31 is a housing that supports the support frame 32 so that it can move perpendicular to the floor. The support frame 32 is a frame provided on the upper part of the base 31. The support frame 32 supports the top plate 33 so that it can slide along the direction of imaging in supine position. A subject P in a supine position is placed on the top plate 33.

[0027] The bed drive unit 34 is housed within the casing of the bed 30. The bed drive unit 34 is a motor or actuator that generates power to move the top plate 33 on which the subject P is placed and the support frame 32. The bed drive unit 34 operates according to control by the processing circuit 44 and the console 40, etc.

[0028] Here, we will describe each imaging mode performed by the X-ray CT apparatus 1 of this embodiment. The X-ray CT scanner 1 has a supine imaging mode for imaging a subject P in a supine position, an upright imaging mode for imaging a subject P in an upright position, and a seated imaging mode for imaging a subject P in a seated position. Supine imaging is an example of a first imaging using the bed 30, and the positional relationship between the stand 10 and the bed 30 in supine imaging mode is an example of a first positional relationship for performing the first imaging. Upright imaging and seated imaging are examples of second imaging without using the bed 30, and the positional relationship between the stand 10 and the bed 30 in upright imaging mode and seated imaging mode is an example of a second positional relationship for performing the second imaging.

[0029] Here, we will explain the state of the scanner 11 and bed 30 in each shooting mode. Figure 2 is a perspective view showing the positional relationship between the scanner 11 and bed 30 in supine shooting mode. This positional relationship is an example of the first positional relationship. Figure 3 is a view of the scanner 11 and bed 30 from above in supine shooting mode. Figure 4 is a perspective view showing the positional relationship with the scanner 11 in standing shooting mode. Figure 5 is a perspective view showing the positional relationship with the scanner 11 in seated shooting mode. The positional relationships in Figures 4 and 5 are an example of the second positional relationship. Figure 6 is a view of the scanner 11 and bed 30 from above in standing shooting mode and seated shooting mode. Note that the bed 30 is not shown in Figures 4 and 5.

[0030] As shown in Figures 2 and 5, in supine imaging mode, the scanner 11 is fixed with the central axis of the opening 19 approximately parallel to the Z-axis direction. At this time, the bed 30 is moved to imaging position B. The subject P is in a supine position on the tabletop 33. In this state, imaging is performed by inserting the tabletop 33 into the opening 19 along the Z-axis direction. Imaging position B is set in the vicinity of the scanner 11, at a position away from the scanner 11 in the Z-direction. Imaging position B is also set to a position in which the tabletop 33 can be inserted into the opening 19 and which includes the movable range A of the scanner 11. The movable range A of the scanner 11 is the range that the scanner 11 passes through in the horizontal direction (X-axis direction and Z-axis direction) when the scanner 11 is tilted.

[0031] As shown in Figures 3 and 6, in standing imaging mode, the scanner 11 is fixed with the central axis of the aperture 19 approximately parallel to the Y-axis direction (vertical direction). At this time, the bed 30 is moved to the retracted position C. The retracted position C is set to a position away from the movable range A of the scanner 11, and also to a position moved away from the scanner 11 in the Z-axis direction relative to the imaging position B. With the standing subject P positioned inside the aperture 19, imaging is performed by moving the scanner 11 up and down by the lifting mechanism.

[0032] As shown in Figures 4 and 6, in seated imaging mode, imaging is performed on a subject P seated in a chair or wheelchair. In seated imaging mode, similar to standing imaging mode, the scanner 11 is fixed with the central axis of the opening 19 approximately parallel to the Y-axis direction (vertical direction). At this time, the bed 30 is moved to the retracted position C. With the subject P seated in the wheelchair or chair positioned within the opening 19, imaging is performed by moving the scanner 11 up and down by the lifting mechanism.

[0033] As described above, in standing and sitting imaging modes, the subject's body axis is approximately perpendicular to that of the supine imaging mode. The Z-axis direction may also be called the imaging direction in supine imaging or the long axis direction of the bed, and the X-axis direction may be called the width direction of the bed. The Y-axis direction may also be called the imaging direction in standing and sitting imaging.

[0034] Returning to Figure 1, the X-ray CT apparatus 1 further includes a moving mechanism 50. The moving mechanism 50 is connected to the patient bed 30 and moves the patient bed 30 along a predetermined direction of movement. In this embodiment, the moving mechanism 50 moves the patient bed 30 along its long axis (Z axis direction, the imaging direction for supine imaging). The moving mechanism 50 is, for example, a linear motion mechanism such as a motor or actuator that generates power to move the patient bed 30. Alternatively, the moving mechanism 50 may consist of a trolley that can travel on rails provided on the floor of the examination room along the Z axis direction, and a linear motion mechanism that drives the trolley. The moving mechanism 50 is connected to the console 40 via a control device 21. The control device 21 has the function of controlling the operation of the moving mechanism 50 according to the control of the console 40, and moves the patient bed 30 along a predetermined direction of movement according to the control of the console 40. By controlling the drive of the moving mechanism 50, the control device 21 controls the patient bed 30 and the stand 10 to be in an appropriate state according to the imaging mode.

[0035] The console 40 includes a memory 41, a display 42, an input interface 43, and a processing circuit 44. Data communication between the memory 41, the display 42, the input interface 43, and the processing circuit 44 is performed via a bus (BUS). Although the console 40 is described separately from the mounting base 10, the mounting base 10 may include the console 40 or some of its components.

[0036] Memory 41 is a storage device such as a Hard Disk Drive (HDD), Solid State Drive (SSD), or integrated circuit memory device that stores various types of information. Memory 41 may also be a portable storage medium other than an HDD or SSD, such as a Compact Disc (CD), Digital Versatile Disc (DVD), Blu-ray® Disc (BD), or flash memory. Memory 41 may also be a drive device that reads and writes various types of information to and from semiconductor memory elements such as flash memory or RAM. Furthermore, the storage area of ​​Memory 41 may be located within the X-ray CT apparatus 1 or in an external storage device connected via a network.

[0037] The display 42 displays various types of information. Various types of displays can be used as the display 42 as appropriate. For example, the display 42 can be a liquid crystal display (LCD), a cathode ray tube (CRT) display, an organic electroluminescent display (OLED), or a plasma display. The display 42 may be installed anywhere in the control room. The display 42 may also be installed on the stand 10. The display 42 may be a desktop type, or it may consist of a tablet terminal or the like that can communicate wirelessly with the console 40. One or more projectors may be used as the display 42.

[0038] The input interface 43 receives various input operations from the user, converts the received input operations into electrical signals, and outputs them to the processing circuit 44. The user may be, for example, a doctor or technician, and may be called an operator. As appropriate, the input interface 43 can be a mouse, keyboard, trackball, switch, button, joystick, touchpad, and touch panel display. In this embodiment, the input interface 43 is not limited to having physical operating 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 these electrical signals to the processing circuit 44 is also included as an example of the input interface 43. Furthermore, the input interface 43 may be provided on the stand 10. In addition, the input interface 43 may consist of the console 40 main unit and a tablet terminal or the like that can communicate wirelessly.

[0039] The processing circuit 44 controls the operation of the entire X-ray CT apparatus 1 in accordance with the electrical signals of input operations output from the input interface 43. The processing circuit 44 generates image data based on the electrical signals output from the X-ray detector 13. For example, the processing circuit 44 has a processor such as a CPU, MPU, or GPU and memory such as ROM or RAM as hardware resources. The processing circuit 44 executes system control functions 441, imaging control functions 442, mode switching functions 443, image generation functions 444, and display control functions 445 using a processor that executes programs loaded into memory.

[0040] Furthermore, each function is not limited to being implemented by a single processing circuit. It is also acceptable to combine multiple independent processors to form a processing circuit, with each processor executing a program to realize each function.

[0041] In the system control function 441, the processing circuit 44 controls each part of the X-ray CT apparatus 1 according to the deployed control program. In addition, in the system control function 441, the processing circuit 44 controls the drive of the patient table 30 via the control device 21.

[0042] In the imaging control function 442, the processing circuit 44 controls the X-ray high-voltage device 15, the control device 21, and the DAS 18 according to the imaging conditions to perform X-ray CT imaging.

[0043] In the mode switching function 443, the processing circuit 44 controls the lifting mechanism and the tilt mechanism to adjust the state of the scanner 11 to a position and orientation corresponding to the shooting mode. In addition, in the mode switching function 443, the processing circuit 44 controls the moving mechanism 50 to move the bed 30 to an appropriate position according to the shooting mode. At this time, when switching to a shooting mode in which the bed 30 is used, the processing circuit 44 moves the bed 30 to a position that overlaps with the range of motion of the scanner 11, and when switching to a shooting mode in which the bed 30 is not used, it moves the bed 30 so that it does not overlap with the range of motion of the scanner 11.

[0044] For example, based on receiving a signal to transition from supine imaging mode to standing or seated imaging mode, the processing circuit 44 tilts the scanner 11 and controls the movement mechanism 50 so that the scanner 11 and the bed 30 move away from each other. At this time, the processing circuit 44 controls the movement mechanism 50 via the control device 21 to move the bed 30 from imaging position B to retracted position C along the Z-axis.

[0045] A signal that transitions from supine imaging mode to standing imaging mode or seated imaging mode is an example of a first signal that transitions from a first positional relationship to a second positional relationship. Also, the control that moves the bed 30 away from the scanner 11 along the Z-axis is an example of a first control. That is, in the mode switching function 443, the processing circuit 44 performs a first control that controls the movement mechanism 50 so that the stand 10 and the bed 30 move away from each other, based on a first signal that transitions from a first positional relationship when performing a first imaging using the bed 30 to a second positional relationship when performing a second imaging without using the bed 30. The processing circuit 44 that performs the mode switching function 443 is an example of a control unit.

[0046] Furthermore, based on receiving a signal to transition from standing or sitting imaging mode to supine imaging mode, the processing circuit 44 tilts the scanner 11 and controls the movement mechanism 50 so that the scanner 11 and the bed 30 move closer together. At this time, the processing circuit 44 controls the movement mechanism 50 via the control device 21 to move the bed 30 from the retracted position C to the imaging position B along the Z-axis.

[0047] The signal for transitioning from standing or sitting imaging mode to supine imaging mode is an example of a second signal for transitioning from a second positional relationship to a first positional relationship. Also, the control to move the bed 30 in the direction closer to the scanner 11 along the Z-axis is an example of a second control. That is, in the mode switching function 443, the processing circuit 44 executes a second control to control the movement mechanism 50 so that the stand 10 and the bed 30 move closer together, based on the second signal for transitioning from the second positional relationship when performing a second imaging without using the bed 30 to the first positional relationship when performing a first imaging using the bed 30. The processing circuit 44 that executes the mode switching function 443 is an example of a control unit.

[0048] Furthermore, in the mode switching function 443, the processing circuit 44 can also acquire both the first signal and the second signal, or at least one of them, by receiving an inspection order from an external device. For example, in the mode switching function 443, the processing circuit 44 can acquire at least one of the first signal and the second signal by receiving an inspection order from a Radiology Information System (RIS) server or the like that includes a first signal or a second signal indicating a transition in imaging mode.

[0049] Furthermore, in the mode switching function 443, the processing circuit 44 receives an examination order including the posture information of the subject P from, for example, the RIS server, and determines whether a transition in the imaging mode is necessary. In addition, if the processing circuit 44 determines that a transition in the imaging mode is necessary in the mode switching function 443, it can further generate a first signal or a second signal.

[0050] In the image generation function 444, the processing circuit 44 generates a CT image by performing a reconstruction process on projection data relating to the subject P. Reconstruction methods include filtered back projection and iterative reconstruction. Alternatively, a reconstruction process incorporating machine learning-based denoising may be used. The processing circuit 44 converts the CT image into a cross-sectional image of an arbitrary cross-section or a rendered image of an arbitrary viewpoint direction. This conversion is performed based on input operations received from the user via the input interface 43. For example, the processing circuit 44 generates a rendered image of an arbitrary viewpoint direction by applying 3D image processing such as volume rendering, surface volume rendering, pixel value projection, MPR (Multi-Planer Reconstruction) processing, or CPR (Curved MPR) processing to the reconstructed image data.

[0051] In the display control function 445, the processing circuit 44 displays the generated CT image and rendered image on, for example, the display 42.

[0052] Although console 40 has been described as a single console that performs multiple functions, it is also acceptable for multiple functions to be performed by separate consoles. The processing circuit 44 is not limited to being included in console 40; it may also be included in an integrated server that performs processing on projection data acquired by multiple medical imaging devices in a unified manner. Post-processing may be performed on either console 40 or an external workstation. Furthermore, processing may be performed simultaneously on both console 40 and the workstation.

[0053] The X-ray CT scanner 1 can be of various types, including third-generation CT and fourth-generation CT, and any type can be applied to this embodiment. Here, the third-generation CT is a Rotate / Rotate-Type in which the X-ray tube and detector rotate together around the subject. The fourth-generation CT is a Stationary / Rotate-Type in which a large number of X-ray detection elements are fixed in a ring-shaped array, and only the X-ray tube rotates around the subject.

[0054] Although not shown in the diagram, the X-ray CT scanner 1 may also be equipped with a communication interface. The communication interface is an interface that connects the X-ray CT scanner 1 to a workstation, PACS (Picture Archiving and Communication System), HIS (Hospital Information System), RIS (Radiology Information System), etc., via a LAN (Local Area Network) or the like. The communication interface sends and receives various types of information between the connected workstation, PACS, HIS, and RIS.

[0055] Next, the operation of the X-ray CT apparatus 1 according to this embodiment will be described. Figure 7 is a flowchart showing an example of the procedure for the first mode switching process performed by the mode switching function 443 of the processing circuit 44. The first mode switching process is performed when switching the X-ray CT apparatus 1 from supine imaging mode to standing imaging mode or seated imaging mode. Here, as an example, the case of switching from supine imaging mode to standing imaging mode will be described, but standing imaging may be replaced with seated imaging. Note that the processing procedure described below is merely an example, and each process may be modified as much as possible. In addition, steps in the processing procedure described below can be omitted, replaced, and added as appropriate depending on the embodiment.

[0056] The first mode switching process begins in supine imaging mode. Figure 8 shows the positional relationship between the scanner 11 and the bed 30 in supine imaging mode. In supine imaging mode, the central axis of the aperture 19 of the scanner 11 is fixed in the horizontal direction (Z-axis direction), and the bed 30 is installed at imaging position B. This positional relationship is an example of the first positional relationship.

[0057] When an instruction to switch to standing imaging mode is received (step S101-Yes), the processing circuit 44 moves the bed 30 from imaging position B to retracted position C along the Z-axis (step S102). Figure 9 shows the state after the bed 30 has moved to retracted position C from the state shown in Figure 8. When the bed 30 moves to retracted position C, the processing circuit 44 tilts the scanner 11 by 90 degrees and fixes it so that the central axis of the aperture 19 faces vertically (Y-axis direction) (step S103). Figure 10 shows the positional relationship between the scanner 11 and the bed 30 when the scanner 11 has been tilted from the state shown in Figure 9. This positional relationship is an example of a second positional relationship.

[0058] Once the tilt of the scanner 11 is complete, the subject moves inside the opening 19, and standing imaging is performed by the vertical movement of the scanner 11. At this time, the bed 30 has moved to a retracted position C, away from the movable range A of the scanner 11, so imaging can be performed without interference between the scanner 11 and the bed 30.

[0059] Figure 11 is a flowchart showing an example of the procedure for the second mode switching process performed by the mode switching function 443 of the processing circuit 44. The second mode switching process is performed when switching the X-ray CT apparatus 1 from standing or sitting mode to supine mode. Here, as an example, the case of switching from standing mode to supine mode will be described, but standing mode may be replaced with sitting mode. Note that the processing procedure described below is merely an example, and each process may be modified as much as possible. Furthermore, steps in the processing procedure described below can be omitted, replaced, and added as appropriate, depending on the embodiment.

[0060] The second mode switching process begins in the standing imaging mode. Figure 12 shows the positional relationship between the scanner 11 and the bed 30 in the standing imaging mode. In the standing imaging mode, the central axis of the aperture 19 of the scanner 11 is fixed in the vertical direction (Y-axis direction), and the bed 30 is set in the retracted position C. This positional relationship is an example of the second positional relationship.

[0061] When an instruction to switch to supine imaging mode is received (step S201-Yes), the processing circuit 44 tilts the scanner 11 90 degrees from the state in which the central axis of the aperture 19 is facing horizontally (Z-axis direction) and fixes it in the state in which the central axis of the aperture 19 is facing vertically (Y-axis direction) (step S202). Figure 13 shows the state in which the scanner 11 has been tilted from the state shown in Figure 12. When the tilt of the scanner 11 is completed, the processing circuit 44 moves the bed 30 from the retracted position C to the imaging position B along the Z-axis direction (step S203). Figure 14 shows the positional relationship between the scanner 11 and the bed 30 when the bed 30 has moved to the imaging position B from the state shown in Figure 13. This positional relationship is an example of the first positional relationship.

[0062] Once the movement of the bed 30 is complete, the top plate 33 on which the subject is placed is transported into the opening 19 of the scanner 11, and supine imaging is performed. At this time, since the bed 30 has moved to imaging position B adjacent to the movable range A of the scanner 11, imaging can be performed while suppressing the sagging of the top plate 33.

[0063] The X-ray CT apparatus 1 of this embodiment comprises a stand 10 equipped with a scanner 11 and a support column 20, a patient bed 30 having a top plate 33, a moving mechanism 50, and a console 40. The moving mechanism 50 moves the patient bed 30 in the Z-axis direction. The console 40 controls the moving mechanism 50 so that the stand 10 and the patient bed 30 move apart based on a signal to tilt the scanner 11 from supine imaging mode to standing imaging mode or seated imaging mode. At this time, the console 40 moves the patient bed 30 away from the stand 10 and then tilts the scanner 11.

[0064] With the above configuration, according to the X-ray CT apparatus 1 of this embodiment, when switching from a supine imaging mode using the bed 30 to standing or sitting imaging without using the bed 30, the bed 30 can be automatically moved to a retracted position C away from the scanner 11. This prevents interference between the scanner 11 and the bed 30 during standing or sitting imaging without requiring a user such as a doctor or technician to manually move the bed 30.

[0065] Furthermore, the console 40 of this embodiment controls the movement mechanism 50 so that the stand 10 and the bed 30 move closer together based on a signal to tilt the scanner 11 from standing or sitting imaging mode to supine imaging mode. At this time, after tilting the scanner 11, the console 40 moves the bed 30 in a direction that moves it closer to the stand 10.

[0066] With the above configuration, the X-ray CT scanner 1 of this embodiment can automatically move the bed 30 to the imaging position B near the scanner 11 when performing supine imaging using the bed 30, from a standing or sitting imaging mode without using the bed 30. This prevents deterioration of positional accuracy due to sagging of the tabletop 33 during supine imaging, without requiring users such as doctors or technicians to manually move the bed 30.

[0067] (First variation) In the above embodiment, an example was described in which the bed 30 is moved along the long axis direction (Z axis direction) when switching shooting modes. In this modified example, the bed 30 is moved along the width direction (X axis direction) of the bed 30 according to the shooting mode. The moving mechanism 50 in this modified example moves the bed 30 along the width direction (X axis direction) of the bed 30.

[0068] Figure 15 is a top view of the positional relationship between the scanner 11 and the bed 30 in supine imaging mode. Figure 16 is a top view of the positional relationship between the scanner 11 and the bed 30 in standing imaging mode and sitting imaging mode. In standing imaging mode and sitting imaging mode, the bed 30 is moved to the retracted position C. Retracted position C is set to a position away from the movable range A of the scanner 11, and moved away from the scanner 11 in the X-axis direction relative to imaging position B. This positional relationship is an example of the second positional relationship.

[0069] In this modified version, when a command is received to switch from supine imaging mode to standing or seated imaging mode, the bed 30 is moved from imaging position B to retracted position C along the X-axis, and then the scanner 11 is tilted. Also, when a command is received to switch from standing or seated imaging mode to supine imaging mode, the scanner 11 is tilted, and then the bed 30 is moved from retracted position C to imaging position B along the X-axis.

[0070] (Second variation) Furthermore, depending on the shooting mode, the bed 30 may be moved along the vertical direction (Y-axis direction). In this modified example, the vertical direction (Y-axis direction) is the direction of movement. The movement mechanism 50 moves the bed 30 along the vertical direction (Y-axis direction). The retracted position is set to a position away from the movable range A of the scanner 11, and moved away from the scanner 11 in the Y-axis direction relative to the shooting position. The retracted position may be set above the shooting position or below the shooting position. The retracted position may be set inside the ceiling or floor. The movement mechanism 50 may be a mechanism fixed to the ceiling to suspend the bed 30, or a loading mechanism that loads the bed 30 into a space pre-provided below the floor.

[0071] In this modified version, when an instruction to switch from supine imaging mode to standing or seated imaging mode is received, the bed 30 is moved from the imaging position to the retracted position along the Y-axis, and then the scanner 11 is tilted. Also, when an instruction to switch from standing or seated imaging mode to supine imaging mode is received, the scanner 11 is tilted, and then the bed 30 is moved from the retracted position to the imaging position along the Y-axis.

[0072] (Third variation) Furthermore, depending on the shooting mode, the bed 30 may be rotated around an axis of rotation that aligns with the vertical direction (Y-axis direction). In this modified example, the direction of rotation around the axis of rotation becomes the direction of movement.

[0073] Figure 17 is a view from above of the positional relationship between the scanner 11 and the bed 30 in supine imaging mode. Figure 18 is a view from above of the positional relationship between the scanner 11 and the bed 30 in standing imaging mode and sitting imaging mode. In standing imaging mode and sitting imaging mode, the bed 30 is moved to the retracted position C. Retracted position C is set to a position away from the movable range A of the scanner 11, and to a position where the bed 30 is rotated 90 degrees around the axis of rotation axis R1 which is approximately parallel to the vertical direction with respect to imaging position B. This positional relationship is an example of the second positional relationship. The moving mechanism 50 is attached to the bed 30 and rotates the bed 30 around the axis of rotation axis R1.

[0074] In this modified version, when a command is received to switch from supine imaging mode to standing imaging mode or sitting imaging mode, the bed 30 is rotated around the axis of rotation axis R1 to move the bed 30 from imaging position B to retracted position C, and then the scanner 11 is tilted. Also, when a command is received to switch from standing imaging mode or sitting imaging mode to supine imaging mode, the scanner 11 is tilted, and then the bed 30 is rotated around the axis of rotation axis R1 to move the bed 30 from retracted position C to imaging position B.

[0075] (Fourth variation) Furthermore, depending on the shooting mode, the bed 30 may be rotated around an axis of rotation that is inclined with respect to the long axis (Z axis) and the vertical direction (Y axis) of the bed 30. In this modified example, the direction of rotation around this axis of rotation becomes the direction of movement.

[0076] Figure 19 is a perspective view showing the positional relationship between the scanner 11 and the bed 30 in supine imaging mode. Figure 20 is a perspective view showing the positional relationship between the scanner 11 and the bed 30 in standing imaging mode and sitting imaging mode. In standing imaging mode and sitting imaging mode, the bed 30 is moved to the retracted position C. The retracted position is set to a position away from the movable range A of the scanner 11, and to a position where the bed 30 is rotated 180 degrees around the axis of the rotation axis R2 relative to the imaging position B. This positional relationship is an example of the second positional relationship. The moving mechanism 50 is attached to the bed 30 and rotates the bed 30 around the axis of the rotation axis R2.

[0077] In this modified version, when an instruction to switch from supine imaging mode to standing or seated imaging mode is received, the bed 30 is rotated around the axis of rotation axis R2 to move the bed 30 from imaging position B to retracted position C, and then the scanner 11 is tilted. Also, when an instruction to switch from standing or seated imaging mode to supine imaging mode is received, the scanner 11 is tilted, and then the bed 30 is rotated around the axis of rotation axis R2 to move the bed 30 from retracted position C to imaging position B.

[0078] (Fifth variation) Alternatively, instead of moving the bed 30, the stand 10 may be moved depending on the shooting mode. In this case, the moving mechanism 50 is attached to the stand 10 and moves the stand 10 along the direction of movement. In this modified example, the moving mechanism 50 moves the stand 10 along the long axis of the bed 30 (Z axis, the shooting direction for supine position imaging). In this modified example, the long axis of the bed 30 (Z axis, the shooting direction for supine position imaging) is the direction of movement.

[0079] Figure 21 shows the positional relationship between the scanner 11 and the bed 30 in supine imaging mode, viewed from above. Figure 22 shows the positional relationship between the scanner 11 and the bed 30 in standing imaging mode and sitting imaging mode, viewed from above.

[0080] As shown in Figure 21, in supine imaging mode, the scanner 11 is fixed with the central axis of the opening 19 approximately parallel to the Z-axis direction. At this time, the stand 10 is moved to imaging position D. Imaging position D is set in the vicinity of the bed 30, at a position away from the bed 30 in the Z-direction. Imaging position D is also set at a position where the top plate 33 can be inserted into the opening 19, and where the movable range of the scanner 11 overlaps with imaging position B of the bed 30. This positional relationship is an example of a first positional relationship.

[0081] As shown in Figure 22, in standing or sitting imaging mode, the scanner 11 is fixed with the central axis of the aperture 19 approximately parallel to the Y-axis direction (vertical direction). At this time, the stand 10 is moved to the retracted position E. The retracted position E is set to a position where the movable range A of the scanner 11 does not overlap with the imaging position B of the bed 30, and is moved away from the bed 30 in the Z-axis direction relative to the imaging position D. This positional relationship is an example of the second positional relationship.

[0082] In this modified version, when a command is received to switch from supine imaging mode to standing or seated imaging mode, the mount 10 is moved along the Z-axis from imaging position D to retracted position E, and then the scanner 11 is tilted. Also, when a command is received to switch from standing or seated imaging mode to supine imaging mode, the scanner 11 is tilted, and then the mount 10 is moved along the Z-axis from retracted position E to imaging position D.

[0083] Alternatively, instead of moving the frame 10 in the Z-axis direction, the frame 10 may be moved in the vertical direction (Y-axis direction) or in the width direction (X-axis direction) of the bed 30. In other words, the direction of movement of the frame 10 by the movement mechanism 50 may be in the vertical direction (Y-axis direction) or in the width direction (X-axis direction) of the bed 30.

[0084] (Sixth variation) Furthermore, depending on the shooting mode, the mount 10 may be rotated around an axis of rotation that is approximately parallel to the vertical direction. In this modified example, the direction of rotation centered on the vertical direction becomes the direction of movement.

[0085] Figure 23 is a view from above of the positional relationship between the scanner 11 and the bed 30 in supine imaging mode. Figure 24 is a view from above of the positional relationship between the scanner 11 and the bed 30 in standing imaging mode and sitting imaging mode. In standing imaging mode and sitting imaging mode, the stand 10 is moved to the retracted position E. The retracted position E is set to a position where the movable range A of the scanner 11 does not overlap with the imaging position B of the bed 30, and where the stand 10 is rotated 90 degrees around the central axis of the support column 20 relative to the imaging position D. This positional relationship is an example of the second positional relationship. The moving mechanism 50 is attached to the support column 20 and rotates the stand 10 around the axis of rotation R3 which is substantially parallel to the vertical direction.

[0086] In this modified version, when a command to switch from supine imaging mode to standing or seated imaging mode is received, the stand 10 is rotated around the axis of rotation axis R3 to move the stand 10 from imaging position D to retracted position E, and then the scanner 11 is tilted. Also, when a command to switch from standing or seated imaging mode to supine imaging mode is received, the scanner 11 is tilted, and then the stand 10 is rotated around the axis of rotation axis R3 to move the stand 10 from retracted position E to imaging position D.

[0087] (Other variations) Furthermore, both the mount 10 and the bed 30 may be provided with a moving mechanism, and both the mount 10 and the bed 30 may be moved according to the shooting mode. The direction of movement of the mount 10 and the direction of movement of the bed 30 may be the same or different.

[0088] For example, in addition to the moving mechanism 50 for moving the frame 10, a second moving mechanism for moving the bed 30 is provided. The second moving mechanism may move the frame 10 along the same direction as the moving mechanism 50, or it may move the frame 10 along a different direction (second moving direction) from the moving mechanism 50.

[0089] When both the stand 10 and the bed 30 are provided with a moving mechanism, the processing circuit 44 uses a mode switching function 443 to move the stand 10 and bed 30 closer together when switching to a supine imaging mode that uses the bed 30, and moves the stand 10 and bed 30 so that the range of motion of the scanner 11 does not overlap with the position of the bed 30 when switching to an upright imaging mode or a seated imaging mode that does not use the bed 30. This provides the same effects as in the above embodiments.

[0090] (Common configuration of the above embodiment and modified example) An X-ray CT apparatus 1 of any of the embodiments and modifications described above includes a moving mechanism 50 and a control unit (for example, a processing circuit 44 of the console 40). The moving mechanism 50 moves at least one of the pedestal 10 and the patient bed 30 along the direction of movement. Based on a first signal indicating a transition from a first positional relationship between the pedestal 10 and the patient bed 30 when performing a first imaging (for example, supine imaging) using the patient bed 30 to a second positional relationship between the pedestal 10 and the patient bed 30 when performing a second imaging (for example, standing or sitting imaging) without using the patient bed 30, the control unit (for example, a processing circuit 44 of the console 40) tilts the scanner 11 and controls the moving mechanism 50 so that the pedestal 10 and the patient bed 30 move away from each other. Alternatively, based on receiving a second signal indicating a transition from the second positional relationship to the first positional relationship, the control unit (for example, a processing circuit 44 of the console 40) tilts the scanner 11 and controls the moving mechanism 50 so that the pedestal 10 and the patient bed 30 move closer together.

[0091] According to at least one embodiment described above, the risk of interference between the bed and the mount when changing the shooting mode can be reduced.

[0092] In the above description, the term "processor" refers to circuits such as CPUs, GPUs, or Application Specific Integrated Circuits (ASICs), programmable logic devices (e.g., Simple Programmable Logic Devices (SPLDs), Complex Programmable Logic Devices (CPLDs), and Field Programmable Gate Arrays (FPGAs)). The processor implements its functions by reading and executing programs stored in memory circuits. Alternatively, instead of storing programs in memory circuits, the processor may be configured to directly incorporate programs into its circuits. In this case, the processor implements its functions by reading and executing programs incorporated into the circuits. Furthermore, instead of executing a program, the processor may implement functions corresponding to the program through a combination of logic circuits. In this embodiment, each processor is not limited to being configured as a single circuit; multiple independent circuits may be combined to form a single processor and implement its functions. Moreover, multiple components may be integrated into a single processor to implement its functions.

[0093] While several embodiments have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These embodiments can be implemented in a variety of other forms, and various omissions, substitutions, modifications, and combinations of embodiments are possible without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of Symbols]

[0094] 1...X-ray CT device 10… Stand 11… Scanner 12...X-ray tube 13…X-ray detector 14…Rotating frame 15…X-ray high-voltage device 16...Wedge 17...Collimator 18…DAS) 19...Aperture 20…post 21...Control device 30...Bed 31…Base 32…Support frame 33... Tabletop 34... Bed drive mechanism 40… Console 41…Memory 42…Display 43…Input Interface 44… Processing circuit 441... System control function 442...Shooting control function 443...Mode switching function 444...Image generation function 445…Display control function 50...Movement mechanism A... Range of motion B, D... Shooting positions C, E...Evacuation position R1, R2, R3... Rotation axes

Claims

1. A stand having a scanner with an imaging system and a stand that supports the scanner so that it can be tilted, A bed having a top plate on which the subject is placed, A moving mechanism for moving at least one of the frame and the bed along the direction of movement, A control unit that performs one of the following: a first control that tilts the scanner and controls the movement mechanism so that the mount and the bed move apart, based on a first signal that transitions from a first positional relationship of the mount and the bed when performing a first imaging using the bed to a second positional relationship of the mount and the bed when performing a second imaging without the bed; and a second control that tilts the scanner and controls the movement mechanism so that the mount and the bed move closer together, based on a second signal that transitions from the second positional relationship to the first positional relationship. An X-ray CT scanner equipped with [a specific feature].

2. The aforementioned direction of movement is along the longitudinal axis of the bed. The X-ray CT apparatus according to claim 1.

3. The aforementioned direction of movement is along the width direction of the bed. The X-ray CT apparatus according to claim 1.

4. The aforementioned direction of movement is along the vertical direction. The X-ray CT apparatus according to claim 1.

5. The aforementioned direction of movement is the direction of rotation around the axis of rotation along the vertical direction. The X-ray CT apparatus according to claim 1.

6. The aforementioned direction of movement is the direction of rotation around a rotation axis that is inclined with respect to the vertical direction and the longitudinal axis direction of the bed. The X-ray CT apparatus according to claim 1.

7. The moving mechanism moves the frame along the direction of movement. The X-ray CT apparatus further comprises a second movement mechanism for moving the patient table along the direction of movement. The X-ray CT apparatus according to claim 1.

8. The bed is further provided with a second movement mechanism that moves the bed along a second movement direction different from the aforementioned movement direction, The moving mechanism moves the frame along the direction of movement. The X-ray CT apparatus according to claim 1.

9. In the first control, the control unit tilts the scanner after separating the frame and the bed. The X-ray CT apparatus according to claim 1.

10. In the second control, the control unit tilts the scanner and then brings the frame and the bed closer together. The X-ray CT apparatus according to claim 1.

11. The first imaging is performed with the central axis of the scanner aligned horizontally. The second imaging is performed with the central axis of the scanner aligned vertically. The X-ray CT apparatus according to claim 1.

12. The first image taken was a supine position image. The second type of imaging described above is either standing or sitting. The X-ray CT apparatus according to claim 1.

13. The control unit controls the movement mechanism so that the bed is positioned in a location that overlaps with the movable range of the scanner in the first positional relationship, and controls the movement mechanism so that the bed is positioned in a location that does not overlap with the movable range of the scanner in the second positional relationship. The X-ray CT apparatus according to claim 1.

14. A control method for an X-ray CT apparatus comprising a stand having a scanner with an imaging system and a stand that supports the scanner so as to be tiltable, a bed having a top plate on which a subject is placed, and a movement mechanism that moves at least one of the stand and the bed along the direction of movement, Based on a first signal indicating a transition from a first positional relationship between the stand and the bed when performing a first imaging using the bed to a second positional relationship between the stand and the bed when performing a second imaging without the bed, the scanner is tilted and the movement mechanism is controlled so that the stand and the bed move apart. Alternatively, based on a second signal indicating a transition from the second positional relationship to the first positional relationship, the scanner is tilted and the movement mechanism is controlled so that the stand and the bed move closer together. Control method.

Images