Medical image diagnosis apparatus, bed apparatus, and bed control method

Abstract

To reduce the time necessary for generating an image.SOLUTION: A medical image diagnosis apparatus according to one embodiment includes an imaging device, multiple sensors, a top plate, a support frame, a computation unit, a control unit, and an exclusion unit. The imaging device captures an image of a subject. The multiple sensors detect the body pressure of the subject. The top plate is provided with the sensors and allows the subject to be placed thereon. The support frame supports the top plate movably. The computation unit computes, based on variations in the body pressure of the subject during execution of imaging of the subject by the imaging device, an amount of movement of the top plate to a predetermined imaging position. The control unit controls the movement of the support frame in accordance with the computed movement amount. The exclusion unit excludes, from display targets, an image concerning the variation of the body pressure of the subject on the basis of the variation in the body pressure of the subject.SELECTED DRAWING: Figure 6

Description

[Technical Field]

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

[0002] Medical imaging diagnostic devices, such as X-ray computed tomography devices and magnetic resonance imaging devices, sometimes scan a subject while moving a tabletop on which the subject is placed. In this case, the medical imaging diagnostic device has a helical mechanism that scans the subject while moving the tabletop. Medical imaging diagnostic devices are capable of high-speed imaging and three-dimensional image construction. Medical imaging diagnostic devices can acquire desired image data by continuously moving the tabletop and reconstructing images in accordance with the subject's body movements.

[0003] As the imaging range expands, motion artifacts may occur due to the subject's own movement due to the length of the imaging time. It is believed that shortening the scan time is an effective way to prevent degradation of imaging quality due to motion artifacts. However, motion artifacts may occur when a specific scan time is recommended and the imaging slice range (slice thickness) is shortened (thinned) to obtain high-contrast images. This creates the problem of time-consuming correction processing to reduce motion artifacts, which increases the processing time required to generate the captured image. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2020-130237 Summary of the Invention [Problem 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 time required for image generation. 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. [Means for solving the problem]

[0006] A medical image diagnostic apparatus according to an embodiment includes an imaging device, multiple sensors, a tabletop, a support frame, a calculation unit, a control unit, and an exclusion unit. The imaging device images a subject. The multiple sensors detect the body pressure of the subject. The tabletop has the multiple sensors and is capable of supporting the subject. The support frame movably supports the tabletop. The calculation unit calculates the amount of movement of the tabletop to a predetermined imaging position based on changes in the subject's body pressure while the imaging device is imaging the subject. The control unit controls movement of the support frame in accordance with the amount of movement. The exclusion unit excludes images related to changes in the subject's body pressure from the display targets based on the changes in the subject's body pressure. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing an example of the arrangement of an X-ray PCCT apparatus according to the first embodiment. [Figure 2] FIG. 2 is a diagram showing an example of a plurality of sensors provided on a top plate according to the first embodiment. [Figure 3] FIG. 3 is a perspective view showing an example of the appearance of the bed apparatus according to the first embodiment. [Figure 4] FIG. 4 is a diagram showing the positional relationship between the gantry device and the top plate together with four link mechanisms according to the first embodiment. [Figure 5] 5 is a diagram showing an example of an X-link when rotating the tabletop along a rotation direction with the Y-axis direction shown in FIG. 3 as the rotation axis according to the first embodiment; [Figure 6] FIG. 6 is a flowchart showing an example of a procedure of a bed control process according to the first embodiment. [Figure 7] FIG. 7 is a diagram showing an example of the configuration of a bed apparatus according to the second embodiment. [Figure 8] FIG. 8 is a flowchart showing an example of a procedure of a bed control process according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, a medical image diagnostic apparatus, a bed apparatus, and a control method will be described with reference to the drawings. In the embodiments, parts with the same reference numerals perform similar operations, and redundant description will be omitted as appropriate. For the sake of concreteness, the medical image diagnostic apparatus will be described below using an X-ray computed tomography apparatus (hereinafter referred to as an X-ray CT (Computed Tomography) apparatus) as an example.

[0009] It should be noted that the device that realizes the technical features of this embodiment is not limited to an X-ray CT device, and can be applied to, for example, a magnetic resonance imaging device (hereinafter referred to as an MRI (Magnetic Resonance Imaging) device), a hybrid device of a nuclear medicine diagnostic device such as a PET (Positron Emission Tomography) device or a SPECT (Single Photon Emission Computed Tomography) device and an X-ray CT device, a hybrid device of a nuclear medicine diagnostic device and an MRI device, an X-ray angiography device, etc.

[0010] (First embodiment) FIG. 1 is a diagram illustrating an example of the configuration of an X-ray CT apparatus 1 according to an embodiment. As shown in FIG. 1, the X-ray CT apparatus 1 includes a gantry 10, also referred to as a gantry, capable of scanning a subject P, a bed 30, and a console 40. In this embodiment, the longitudinal direction of the rotation axis of the rotating frame 13 in a non-tilted state is defined as the Z-axis direction, the direction perpendicular to the Z-axis direction and extending from the center of rotation toward the support column supporting the rotating frame 13 is defined as the X-axis direction, and the direction perpendicular to the Z-axis direction and the X-axis direction is defined as the Y-axis. For convenience of explanation, multiple gantry devices 10 are depicted in FIG. 1, but the X-ray CT apparatus 1 actually includes only one gantry device 10. The gantry 10 may also be referred to as an imaging device or scanner capable of scanning the subject P. That is, the imaging device images the subject P.

[0011] The gantry device 10 and the bed device 30 operate based on operations from an operator via the console device 40 or operations from an operator via an operation unit provided on the gantry device 10 or the bed device 30. The operator may be, for example, a doctor, a radiologist, or a serviceman related to the X-ray CT device 1. The gantry device 10, the bed device 30, and the console device 40 are connected to each other by wire or wirelessly so that they can communicate with each other.

[0012] The gantry device 10 is a scanning device configured to perform X-ray CT imaging on a subject P. The gantry device 10, for example, irradiates the subject P with X-rays and collects projection data from detection data of the X-rays that have passed through the subject P. The gantry device 10 has an imaging system for imaging the subject P and an opening into which the subject P can be inserted. The gantry device 10 has an X-ray tube 11, an X-ray detector 12, a rotating frame 13, an X-ray high-voltage device 14, a control device 15, a wedge 16, a collimator 17, and a DAS (Data Acquisition System) 18. The console device 100 is a computer that controls the gantry device 10.

[0013] The X-ray tube 11 is a vacuum tube that generates X-rays by irradiating thermions from a cathode (filament) toward an anode (target) through the application of high voltage and supply of filament current from the X-ray high voltage device 14. X-rays are generated when thermions collide with the target. The X-rays generated at the tube focus in the X-ray tube 11 pass through an X-ray emission window in the X-ray tube 11 and are shaped into, for example, a cone beam via a collimator 17, and are then irradiated onto the subject P. The X-ray tube 11 may be, for example, a rotating anode type X-ray tube that generates X-rays by irradiating a rotating anode with thermions.

[0014] The X-ray detector 12 detects X-rays emitted from the X-ray tube 11 and passing through the subject P, and outputs an electrical signal corresponding to the X-ray dose to the DAS 18. The X-ray detector 12 has, for example, multiple detection element rows in which multiple detection elements are arranged in the channel direction along an arc centered on the focal point of the X-ray tube 11. The X-ray detector 12 has, for example, a structure in which multiple detection element rows are arranged in the slice direction (column direction, row direction).

[0015] The X-ray CT apparatus 1 is available in a rotate / rotate type (third generation CT) in which the X-ray tube 11 and the X-ray detector 12 rotate together around the subject P, and a stationary / rotate type (fourth generation CT) in which a large number of X-ray detection elements arranged in a ring shape are fixed and only the X-ray tube 11 rotates around the subject P, and either type can be applied to this embodiment. For the sake of specificity, the X-ray CT apparatus 1 of this embodiment will be described below using a third generation CT as an example.

[0016] The X-ray detector 12 is an indirect conversion detector having, for example, a grid, a scintillator array, and a photosensor array. The scintillator array has multiple scintillators, and the scintillators have scintillator crystals that output light with a photon amount corresponding to the amount of incident X-rays. The grid is arranged on the X-ray incident side of the scintillator array and has an X-ray shielding plate that has the function of absorbing scattered X-rays.

[0017] The grid may also be called a collimator (one-dimensional collimator or two-dimensional collimator). The photosensor array has a function of converting the amount of light from the scintillator into an electrical signal according to the amount of light, and includes a photosensor such as a photomultiplier tube (PMT). The X-ray detector 12 may be a direct conversion type detector having a semiconductor element that converts incident X-rays into an electrical signal. The X-ray detector 12 may also be a photon counting type X-ray detector. The X-ray detector 12 is an example of an X-ray detection unit.

[0018] The rotating frame 13 is an annular frame that supports the X-ray tube 11 and the X-ray detector 12 so that they face each other, and rotates the X-ray tube 11 and the X-ray detector 12 using a control device 15, which will be described later. In addition to the X-ray tube 11 and the X-ray detector 12, the rotating frame 13 also supports an X-ray high voltage device 14 and a DAS 18. The rotating frame 13 is rotatably supported by a non-rotating part of the gantry device 10 (for example, a fixed frame, not shown in FIG. 1).

[0019] The rotation mechanism includes, for example, a motor that generates a rotational driving force and a bearing that transmits the rotational driving force to the rotating frame 13 to rotate it. The motor is provided, for example, in the non-rotating part, and the bearing is physically connected to the rotating frame 13 and the motor, so that the rotating frame 13 rotates in response to the rotational force of the motor.

[0020] The rotating frame 13 and the non-rotating part are each provided with a non-contact or contact communication circuit, which allows communication between the unit supported on the rotating frame 13 and the non-rotating part or an external device of the gantry 10. For example, if optical communication is used as the non-contact communication method, the detection data generated by the DAS 18 is transmitted by optical communication from a transmitter having a light-emitting diode (LED) provided on the rotating frame 13 to a receiver having a photodiode provided on the non-rotating part of the gantry 10, and is then transferred from the non-rotating part to the console device 40 by the transmitter.

[0021] As a communication method, other contact-type data transmission methods such as capacitive coupling and radio wave transmission may be used, as well as contact-type data transmission methods using slip rings and electrode brushes. The rotating frame 13 is an example of a rotating part.

[0022] X-ray high voltage device 14 has electrical circuits such as a transformer and a rectifier, and includes a high voltage generator having the function of generating a high voltage to be applied to X-ray tube 11 and a filament current to be supplied to X-ray tube 11, and an X-ray control device that controls the output voltage according to the X-rays irradiated by X-ray tube 11. The high voltage generator may be of a transformer type or an inverter type. X-ray high voltage device 14 may be provided on rotating frame 13 or on the fixed frame side of gantry device 10. X-ray high voltage device 14 is an example of an X-ray high voltage unit.

[0023] The control device 15 has a processing circuit having a CPU (Central Processing Unit) and the like, and a drive mechanism for a motor, an actuator, and the like. The processing circuit has, as hardware resources, a processor such as a CPU or an MPU (Micro Processing Unit) and a memory such as a ROM (Read Only Memory) or RAM (Random Access Memory). The control device 15 may also be realized by a processor such as a GPU (Graphics Processing Unit), an Application Specific Integrated Circuit (ASIC), a programmable logic device (e.g., a Simple Programmable Logic Device (SPLD), a Complex Programmable Logic Device (CPLD), or a Field Programmable Gate Array (FPGA)).

[0024] If the processor is a CPU, for example, the processor realizes its functions by reading and executing a program stored in memory. On the other hand, if the processor is an ASIC, instead of storing a program in memory, the function is directly incorporated into 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 functions. Furthermore, multiple components may be integrated into a single processor to realize its functions.

[0025] The control device 15 has a function of receiving input signals from the console device 40 or an input interface attached to the gantry 10 and controlling the operation of the gantry 10 and the bed 30. For example, the control device 15 receives input signals and controls the rotation of the rotating frame 13, the tilt of the gantry 10, and the operation of the bed 30 and the tabletop 33. Note that the control of tilting the gantry 10 may be realized by the control device 15 rotating the rotating frame 13 around an axis parallel to the X-axis direction based on inclination angle (tilt angle) information input via an input interface attached to the gantry 10.

[0026] The control device 15 may be provided in the gantry device 10 or in the console device 40. The control device 15 may be configured to directly incorporate the program into the circuitry of the processor instead of storing the program in a memory. The control device 15 is an example of a control unit.

[0027] The wedge 16 is a filter for adjusting the amount of X-rays irradiated from the X-ray tube 11. Specifically, the wedge 16 is a filter that transmits and attenuates the X-rays irradiated from the X-ray tube 11 so that the X-rays irradiated from the X-ray tube 11 to the subject P have a predetermined distribution. The wedge 16 is, for example, a wedge filter or a bow-tie filter, and is a filter made by processing aluminum to have a predetermined target angle and a predetermined thickness.

[0028] The collimator 17 is a lead plate or the like for constricting the X-rays transmitted through the wedge 16 to an X-ray irradiation range, and a slit is formed by combining a plurality of lead plates or the like. The collimator 17 is also sometimes called an X-ray aperture.

[0029] The DAS (Data Acquisition System) 18 has an amplifier that amplifies the electrical signals output from each X-ray detection element of the X-ray detector 12 and an A / D converter that converts the electrical signals into digital signals, and generates detection data. The detection data generated by the DAS 18 is transferred to the console device 100. The DAS 18 is an example of a data acquisition unit.

[0030] The detection data generated by the DAS 18 is transferred to the console device 40. The detection data is a set of data including the channel number of the detecting element that generated the data, the column number, the view number indicating the acquired view (also called the projection angle), and a value indicating the detected X-ray dose. The view number may be the order in which the views are acquired (acquisition time), or a number (e.g., 1 to 1000) indicating the rotation angle of the X-ray tube 11. In this embodiment, the term "detection data" simply refers to both pure raw data detected by the X-ray detector 12 and before preprocessing, and raw data obtained by preprocessing the pure raw data. The data before preprocessing (detection data) and the data after preprocessing may also be collectively referred to as projection data.

[0031] The bed device 30 is a device on which a subject P to be scanned is placed and moved, and includes a base 31, a bed driving device 32, a tabletop 33, and a support frame 34. The base 31 is a housing that supports the support frame 34 movably in the vertical direction. The base 31 is equipped with multiple link mechanisms that support the support frame 34 movably in the vertical direction. The support frame 34 movably supports the tabletop 33. The support frame 34 is supported by multiple link mechanisms that can independently move the ends of the tabletop 33 along the vertical direction. Each of the multiple link mechanisms is realized by, for example, a pair of links pivoted in an X shape (hereinafter referred to as X links). The multiple X links corresponding to the multiple link mechanisms will be described later. The link mechanism may also be referred to as an elevation mechanism. For the sake of concreteness, the following description will be given assuming that there are four multiple link mechanisms, i.e., four X links.

[0032] The bed driving device 32 is a motor or actuator that moves the tabletop 33 on which the subject P is placed in the longitudinal direction of the tabletop 33. The bed driving device 32 also includes, for example, a motor that generates power for horizontally moving the end of at least one X link for each of the multiple X links, and a linear guide that transmits the power to, for example, the end of the X link. The method of transmitting the driving motion for each of the multiple link mechanisms is realized by a known method, such as a combination of the motor and the linear guide (which may be referred to as a linear guide actuator). Therefore, a description of the linear guide actuator will be omitted. The method of transmitting the driving motion for each of the multiple link mechanisms is not limited to a linear guide actuator, and various known methods can be applied.

[0033] The tabletop 33 provided on the upper surface of the support frame 34 is a plate on which the subject P is placed. The bed driving device 32 may move the support frame 34 in the longitudinal direction of the tabletop 33 in addition to the tabletop 33.

[0034] The bed device 30 will be described in detail below with reference to FIGS. 2 to 5. FIG. 2 is a diagram showing an example of a plurality of sensors 35 provided on the tabletop 33. FIG. 3 is a perspective view showing an example of the appearance of the bed device 30. As shown in FIGS. 1 to 3, the subject P is placed on the tabletop 33, and a plurality of sensors 35 is provided on the tabletop 33. That is, the tabletop 33 has a plurality of sensors 35 and can accommodate the subject P. Although three sensors 35 are shown in FIG. 2, if, for example, two sensors are arranged along the X-axis direction, a total of six sensors are provided on the tabletop 33 as shown in FIG. 3. Output terminals of the plurality of sensors 35 are electrically connected to the console device 40. As a result, data related to the body pressure of the subject P detected by the plurality of sensors 35 (hereinafter referred to as detected data) is output to the console device 40.

[0035] The multiple sensors 35 detect the body pressure of the subject P placed on the top board 33. The multiple sensors 35 are realized by, for example, weight sensors (which may also be referred to as weight sensors or gravity sensors) or pressure sensors (which may also be referred to as pressure sensors). The weight sensors detect the weight of the subject P placed on the top board 33. The pressure sensors detect the pressure on the top board 33 by the subject P placed on the top board 33. The arrangement of the multiple sensors 35 on the top board 33 is not limited to that shown in FIG. 2, and any number of sensors can be arranged at any position. The arrangement of the multiple sensors 35 is also not limited to that shown in FIGS. 1 to 3, and may be realized by, for example, a sensor sheet such as a pressure-sensitive sheet in which the multiple sensors 35 are arranged in a sheet-like form.

[0036] 3, the tabletop 33 can move along the long axis direction HD (Z-axis direction) of the tabletop 33 by driving the support frame 34 with the bed driving device 32. The tabletop 33 can also move together with the support frame 34 along the vertical direction (Y-axis direction) VD by driving multiple link mechanisms with the bed driving device 32. The tabletop 33 can also rotate together with the support frame 34 along a rotation direction RD with the Y-axis direction LD as the rotation axis by driving multiple link mechanisms with the bed driving device 32.

[0037] FIG. 4 is a diagram showing the positional relationship between the gantry device 10 and the top plate 33, along with four link mechanisms (LM1 to LM4). As shown in FIG. 4, the four link mechanisms (LM1 to LM4) are realized by four X links. The upper ends of the four X links (LM1 to LM4) are connected to the support frame 34 so as to be movable along the longitudinal axis of the top plate 33. The upper ends of the four X links (LM1 to LM4) are also connected to the base 31 via linear guide actuators so as to be movable along the longitudinal axis of the base 31. As a result, the support frame 34 is supported by multiple link mechanisms (X links LM1 to LM4) that can independently move the ends of the top plate 33 along the vertical direction.

[0038] As shown in FIG. 4, the multiple link mechanisms can tilt the tabletop 33. Tilting the tabletop 33 corresponds to an operation TD in which the tabletop 33 is tilted around the X-axis direction as a rotation axis, as shown in FIG. 4. When the tabletop 33 is tilted, as shown in FIG. 4, the height EH of the two X links (LM1, LM2) at one end of the tabletop 33 is lower than the height FH of the two X links (LM3, LM4) at the other end of the tabletop 33. In addition, the heights of the two X links (LM1, LM2) at one end of the tabletop 33 are the same. Furthermore, the heights of the two X links (LM3, LM4) at the other end of the tabletop 33 are the same. As a result, the tabletop 33 tilts around the X-axis direction as a rotation axis.

[0039] 5 is a diagram showing an example of the X links (LM1 to LM4) when rotating the tabletop 33 along the rotation direction RD, with the Y-axis direction LD shown in FIG. 3 as the rotation axis. As shown in FIG. 5, the height H1 of the two X links (LM1, LM3) on the positive side of the X-axis direction is lower than the height H2 of the two X links (LM2, LM4) on the negative side of the X-axis direction. This causes the tabletop 33 to tilt toward the positive side of the X-axis direction. In other words, by adjusting the heights of the two X links (LM1, LM3) on the positive side of the X-axis direction and the heights of the two X links (LM2, LM4) on the negative side of the X-axis direction, the tabletop 33 tilts with the Z-axis direction as the rotation axis.

[0040] The console device 40 has 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, for example, via a bus (BUS). Note that although the console device 40 will be described as being separate from the gantry device 10, the gantry device 10 may include the console device 40 or some of the components of the console device 40.

[0041] The memory 41 is realized by, for example, a semiconductor memory element such as a random access memory (RAM), a flash memory, a hard disk drive (HDD), a solid state drive (SSD), an optical disk, etc. The memory 41 may also be a drive device that reads and writes various information from and to a portable storage medium such as a compact disc (CD), a digital versatile disc (DVD), a flash memory, etc., or a semiconductor memory element such as a random access memory (RAM).

[0042] The memory 41 stores, for example, the detection data output from the DAS 18, the projection data generated by the preprocessing function 442, the reconstructed image reconstructed by the reconstruction processing function 443, the detection data output from the plurality of sensors 35, and a threshold value used in the bed control process described below. The threshold value is a value for determining whether or not the subject P placed on the tabletop 33 has moved based on the detection data. The threshold value for detecting the body movement of the subject P is set in advance. The reconstructed image is, for example, three-dimensional CT image data (volume data) or two-dimensional CT image data. The storage area of the memory 41 may be located within the X-ray CT apparatus 1 or may be located in an external storage device connected via a network.

[0043] The memory 41 is a storage device such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or an integrated circuit storage device that stores various types of information. The memory 41 stores, for example, projection data and reconstructed image data. In addition to an HDD or an SSD, the memory 41 may be a portable storage medium such as a CD (Compact Disc), a DVD (Digital Versatile Disc), or a flash memory, or a drive that reads and writes various types of information from and to a semiconductor memory element such as a RAM (Random Access Memory).

[0044] The storage area of the memory 41 may be located within the console device 100 or within an external storage device connected via a network. The memory 101 also stores a control program according to this embodiment. The memory 41 also stores volume data generated by a pre-scan or a main scan.

[0045] The memory 41 stores programs related to the execution of each of a system control function 441, a preprocessing function 442, a reconstruction processing function 443, an image processing function 444, a calculation function 445, and an exclusion function 446, which are executed by the processing circuitry 44. The memory 41 is an example of a storage unit.

[0046] The display 42 displays various types of information. For example, the display 42 outputs medical images (CT images) generated by the processing circuitry 44, a GUI (Graphical User Interface) for receiving various operations from the user, etc. For example, the display 42 may be a liquid crystal display (LCD), a cathode ray tube (CRT) display, an organic electroluminescence display (OLED), a plasma display, or any other display, as appropriate.

[0047] The display 42 may be provided on the gantry device 10. The display 103 may be a desktop type, or may be configured as a tablet terminal or the like capable of wireless communication with the console device 40. The display 42 corresponds to a display unit.

[0048] The input interface 43 accepts various input operations from the operator, converts the accepted input operations into electrical signals, and outputs the electrical signals to the processing circuitry 44. For example, the input interface 43 accepts from the operator scan conditions for collecting projection data, imaging protocols, reconstruction conditions for reconstructing CT image data, image processing conditions for post-processing of the CT image data, etc. The post-processing may be performed by either the console device 40 or an external workstation. Furthermore, the post-processing may be performed simultaneously by both the console device 40 and the workstation.

[0049] The post-processing defined here is a concept that refers to processing of images reconstructed by the reconstruction processing function 443. Post-processing includes, for example, multi-planar reconstruction (MPR) display of the reconstructed image and rendering of volume data. As the input interface 43, for example, a mouse, keyboard, trackball, switch, button, joystick, touchpad, touch panel display, etc. can be used as appropriate.

[0050] In this embodiment, the input interface 43 is not limited to one having physical operation components such as a mouse, keyboard, trackball, switch, button, joystick, touchpad, and touch panel display. For example, an example of the input interface 43 also includes an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the device and outputs the electrical signal to the processing circuit 44. The input interface 43 is also an example of an input unit. The input interface 43 may also be provided in the gantry device 10. The input interface 43 may also be configured as a tablet terminal or the like that is capable of wireless communication with the console device 40 main body.

[0051] The processing circuitry 44 controls the overall operation of the X-ray CT apparatus 1 in response to, for example, electrical signals of input operations output from the input interface 43. For example, the processing circuitry 44 has, as hardware resources, processors such as a CPU, MPU, or GPU (Graphics Processing Unit), and memories such as ROM and RAM. The processing circuitry 44 executes a system control function 441, a preprocessing function 442, a reconstruction processing function 443, an image processing function 444, a calculation function 445, and an exclusion function 446 using a processor that executes a program loaded in its own memory. Note that each of the functions 441 to 446 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 441 to 446.

[0052] The system control function 441 controls each function of the processing circuitry 44 based on an input operation received from an operator via the input interface 43. The system control function 441 also reads out a control program stored in the memory 41, expands it on the memory in the processing circuitry 44, and controls each part of the X-ray CT apparatus 1 in accordance with the expanded control program. The processing circuitry 44 that realizes the system control function 441 is an example of a system control unit or a control unit.

[0053] The pre-processing function 442 generates projection data by performing pre-processing such as logarithmic conversion, offset correction, inter-channel sensitivity correction, and beam hardening correction on the detection data output from the DAS 18. The generation of projection data conforms to known processing content, so a description thereof will be omitted. The processing circuitry 44 that realizes the pre-processing function 442 is an example of a pre-processing unit.

[0054] The reconstruction processing function 443 generates CT image data by performing reconstruction processing using a filtered back projection (FBP) method or the like on the projection data generated by the preprocessing function 442 based on the reconstruction conditions. The reconstruction processing includes various types of processing such as various correction processes such as scatter correction and beam hardening correction, and application of a reconstruction function under the reconstruction conditions.

[0055] The reconstruction processing performed by the reconstruction processing function 443 is not limited to the FBP method, and known processing such as iterative reconstruction or a deep neural network that outputs a reconstructed image based on input projection data may be used as appropriate. As known processing content can be used as appropriate for the reconstruction to generate a medical image by the reconstruction processing function 443, a description thereof will be omitted. The reconstruction processing function 443 stores the reconstructed CT image data in the memory 41. The processing circuitry 44 that realizes the reconstruction processing function 443 is an example of a reconstruction processing unit.

[0056] The image processing function 444 converts the CT image data generated by the reconstruction processing function 443 into tomographic image data of an arbitrary cross section or three-dimensional image data by a known method based on an input operation received from the operator via the input interface 43. The generation of three-dimensional image data may be executed by the reconstruction processing function 443. As various types of image processing realized by the image processing function 444 can be known processes, a description thereof will be omitted. The image processing function 444 is an example of an image processing unit.

[0057] The calculation function 445 calculates the amount of movement of the top 33 to a predetermined imaging position based on a change in the body pressure of the subject P while the imaging device (e.g., the gantry device 10) is imaging the subject P. Specifically, the calculation function 445 calculates the posture of the subject P placed on the top 33 based on, for example, detection data immediately before a scan is performed on the subject P. The posture of the subject P is, for example, data indicating the distribution of the body pressure of the subject P. The data indicating the distribution of the body pressure corresponds to a map (hereinafter referred to as a body pressure map) indicating the distribution of body pressure corresponding to a predetermined imaging position. The body pressure map corresponds to the posture of the subject P placed on the top 33.

[0058] For ease of explanation, the body pressure map immediately before the scan is performed will be referred to as the reference map below. The reference map corresponds to a predetermined imaging position for the subject P. The predetermined imaging position corresponds to an imaging position (which may be referred to as an initial imaging position) where a scan is performed on the subject P based on an examination order. The predetermined imaging position is set, for example, before imaging (scanning) the subject P based on an examination order or the like. The calculation function 455 stores the reference map in the memory 41.

[0059] The calculation function 445 sequentially calculates body pressure maps based on the detection data output from the multiple sensors 35 while the gantry device 10 is performing imaging of the subject P. Next, the calculation function 445 calculates the difference between the calculated body pressure map and the reference map (hereinafter referred to as the difference map). The calculation function 445 calculates the movement amount of the top 33 to a predetermined imaging position based on the difference map. For example, the calculation function 445 calculates the movement amount of the top 33 (hereinafter referred to as the top movement amount) so that the difference map and the reference map overlap. The difference map and the top movement amount correspond to changes in the body pressure of the subject P.

[0060] The tabletop movement amount includes the movement amount of the tabletop 33 along the long axis direction (Z-axis direction) of the tabletop 33, the movement amount of the tabletop 33 along the vertical direction (Y-axis direction), the rotation angle of the tabletop 33 about the Z-axis direction as the rotation axis, and the rotation angle of the tabletop 33 about the X-axis direction as the rotation axis. The calculation of the tabletop movement amount can be performed by known geometric calculations, so a description thereof will be omitted. The calculation function 445 stores the calculated tabletop movement amount in the memory 41. The processing circuit 44 that realizes the calculation function 445 is an example of a calculation unit.

[0061] When the movement amount of the top exceeds a predetermined threshold, the exclusion function 446 excludes an image relating to a change in the body pressure of the subject P from the display target based on the change in the body pressure of the subject P. The image relating to the change in the body pressure of the subject P is an image obtained by imaging the subject at the time when detection data relating to the body pressure data on which the movement amount of the top is calculated is acquired. In other words, the image relating to the change in the body pressure of the subject P is an image at the time when a change in the body pressure of the subject P occurs, and corresponds to an image at the time when a body movement of the subject P occurs. Specifically, the exclusion function 446 compares the movement amount of the top with a threshold. At this time, the threshold corresponds to the movement amount of the top 33. When the movement amount of the top exceeds the threshold, the exclusion function 446 excludes an image corresponding to a body pressure map corresponding to the change in the body pressure of the subject P from the reconstruction target. For example, the reconstruction processing function 443 excludes an image (projection data) corresponding to a body pressure map relating to a movement amount of the top exceeding the threshold from the reconstruction processing. As a result, the image corresponding to the body pressure map is excluded from the display target. Processing circuitry 44 implementing exclusion function 446 is an example of an exclusion unit.

[0062] In the above description, the object to be compared with the threshold value is the movement amount of the tabletop, but this is not limited to this and may be a difference map. In this case, the threshold for detecting the body movement of the subject P corresponds to a map (hereinafter referred to as a threshold map) in the difference map that indicates the degree of deviation between the body pressure map and the reference map. Furthermore, the threshold-based judgment process (hereinafter referred to as a threshold judgment process) has been described as being performed by the exclusion function 446, but it may also be performed by the calculation function 445. For example, when the calculation function 445 determines that the difference map exceeds the threshold map as the threshold judgment process, it may calculate the movement amount of the tabletop. In this case, the exclusion function 446 excludes from the display target an image corresponding to a body pressure map related to a difference map that exceeds the threshold map.

[0063] The threshold determination process may be performed by a determination function newly provided in the processing circuitry 44. In this case, the processing circuitry 44 that realizes the determination function corresponds to a determination unit.

[0064] Furthermore, if the amount of tabletop movement exceeds a predetermined threshold, the system control function 441 or the control device 15 controls the movement of the support frame 34 so as to move the tabletop 33 according to the amount of tabletop movement. Specifically, the system control function 441 controls the bed driver 32 so as to move the tabletop 33 according to the amount of tabletop movement (translation, rotation). Through this control, the bed driver 32 drives the motors in the linear guide actuators connected to the four X links (LM1 to LM4) to move the blocks fitted to the rails of the linear guides.

[0065] As a result, the distance between the two links on the base 31 side of each of the multiple X links (LM1 to LM4) (hereinafter referred to as the end link distance) is changed according to the amount of tabletop movement. By changing the end link distance, the position of the tabletop 33 in the horizontal and / or vertical directions, and the rotation (tilt) of the tabletop 33 about the major axis direction of the tabletop 33 and / or the minor axis direction of the tabletop 33 as the rotation axis are adjusted.

[0066] The bed control process implemented by the X-ray CT apparatus 1 according to this embodiment configured as described above will be described with reference to Fig. 6. The bed control process is a process for controlling the posture (position and inclination) of the tabletop 33 according to the amount of tabletop movement. Fig. 6 is a flowchart showing an example of the procedure of the bed control process.

[0067] (Cover control processing) (Step S601) Prior to a scan of the subject P, the subject P is placed on the tabletop 33. The plurality of sensors 35 detects the body pressure of the subject P and outputs the detected data to the processing circuitry 44. The processing circuitry 44 generates a reference map based on the detected data output from the plurality of sensors 35 using the calculation function 445. The calculation function 445 stores the reference map in the memory 41.

[0068] (Step S602) The processing circuitry 44 executes a scan on the subject P according to the scan conditions in response to an instruction from the operator via the input interface 43 using the system control function 441. Projection data acquired by executing the scan is stored in the memory 41.

[0069] (Step S603) While a scan is being performed on the subject P, the multiple sensors 35 detect the body pressure of the subject P at predetermined time intervals and output the detected data to the processing circuitry 44. The processing circuitry 44 generates a body pressure map based on the detected data output from the multiple sensors 35 using a calculation function 445. The calculation function 445 stores the body pressure map in the memory 41 in association with shadow data (e.g., view number and acquisition time) that corresponds to the timing of body pressure detection.

[0070] (Step S604) The processing circuitry 44 calculates the amount of movement of the top board based on the body pressure map and the reference map using the calculation function 445. The calculation function 445 stores the amount of movement of the top board in the memory 41.

[0071] (Step S605) The processing circuitry 44 compares the top movement amount with the threshold value using the exclusion function 446. If the top movement amount exceeds the threshold value (Yes in step S605), the process proceeds to step S606. If the top movement amount does not exceed the threshold value (No in step S605), the process proceeds to step S608.

[0072] (Step S606) The processing circuitry 44 excludes projection data corresponding to the body pressure map from the target of reconstruction processing by the exclusion function 446. That is, the exclusion function 446 excludes projection data corresponding to the view number associated with the body pressure map from the target data of reconstruction processing. Note that the projection data corresponding to the view number associated with the body pressure map may be scanned again under the control of the system control function 441.

[0073] (Step S607) The processing circuitry 44 controls the bed driving device 32 via the system control function 441 or the control device 15 to move the bed 33 according to the tabletop movement amount. By this control, the bed driving device 32 drives the motors in the linear guide actuators connected to the four X links (LM1 to LM4). By this drive, the position of the tabletop 33 is moved, and even if the subject P moves, the imaging position for the subject P is maintained at the initial imaging position.

[0074] (Step S608) If the scan is complete (Yes in step S608), the process proceeds to step S609 and subsequent steps. If the scan is not complete (No in step S608), the process proceeds to step S603 and subsequent steps.

[0075] (Step S609) The processing circuitry 44 executes reconstruction processing using the projection data set excluding the projection data to be excluded by the reconstruction processing function 443. At this time, the reconstruction processing function 443 executes reconstruction processing and generates volume data without executing motion artifact reduction processing. The reconstruction processing function 443 stores the volume data generated by the reconstruction processing in the memory 41.

[0076] The processing circuitry 44 uses the image processing function 444 to perform image processing designated by the user on the volume data to generate a display image. The processing circuitry 44 uses the system control function 441 to display the generated display image on the display 42. The generation and display of the display image may be performed in a medical image management system (Picture Archiving and Communication System: PACS). As a result, the projection data to be excluded is excluded from the display targets. The projection data to be excluded (or the image to be excluded) is transferred to and stored in the PACS, for example, together with the volume data.

[0077] The medical image diagnostic apparatus according to the first embodiment described above uses a plurality of sensors 35 to detect the body pressure of the subject P on the tabletop 33 on which the subject P is placed, calculates the amount of movement (single table movement amount) of the tabletop 33 to a predetermined imaging position based on changes in the body pressure of the subject P while the imaging device is imaging the subject P, controls the movement of the support frame 34 that movably supports the tabletop 33 according to the amount of movement, and excludes images related to changes in the body pressure of the subject P from the display targets based on the changes in the body pressure of the subject P. The support frame 34 in the medical image diagnostic apparatus according to the first embodiment is supported by a plurality of link mechanisms that can independently move the ends of the tabletop 33 along the vertical direction. The plurality of link mechanisms in the X-ray CT apparatus 1 according to the first embodiment can tilt the tabletop 33.

[0078] Furthermore, when the amount of top movement exceeds a predetermined threshold, the medical image diagnostic apparatus according to the first embodiment controls the movement of the support frame 34 to move the top 33 in accordance with the amount of top movement, and when the amount of top movement exceeds the predetermined threshold, excludes images relating to changes in the body pressure of the subject P from the display targets. Furthermore, the multiple sensors 35 in the medical image diagnostic apparatus according to the first embodiment are weight sensors that detect the weight of the subject P placed on the top 33 or pressure sensors that detect pressure on the top 33 by the subject P placed on the top 33. Furthermore, the imaging device in the medical image diagnostic apparatus according to the first embodiment is a gantry 10 that can scan the subject P.

[0079] From these facts, the medical image diagnostic apparatus according to the first embodiment can also be provided with a mechanism that automatically detects the body pressure distribution of the subject P obtained from the plurality of sensors 35 provided on the bed device 30, and automatically moves the tabletop 33 to an initial imaging position based on the obtained body pressure distribution in accordance with the body movement of the subject P during imaging. As a result, the medical image diagnostic apparatus according to the first embodiment does not require forced fixation of moving parts of the patient's body to maintain posture during imaging, compared to conventional devices, thereby reducing stress on the subject P during imaging and eliminating the need for interpolation using projection data or the like for body movement correction (correction related to motion artifacts) in image reconstruction, allowing desired images to be obtained in a short time.

[0080] As described above, the medical image processing apparatus according to the first embodiment can reduce the time required for image generation, and can improve the efficiency of examinations of the subject P (throughput of examinations).

[0081] (Second embodiment) The second embodiment aims to realize a bed apparatus capable of automatically moving a tabletop 33 in response to the body movement of a subject P. Fig. 7 is a diagram showing an example of the configuration of a bed apparatus 300 according to the second embodiment. The bed apparatus 300 includes a base 31, a bed driving device 32, a tabletop 33, a support frame 34, and a bed control device 36.

[0082] The base 31, the bed driving device 32, the table top 33, the support frame 34, and the plurality of sensors 35 in the bed device 300 are the same as those in the first embodiment, and therefore their description will be omitted. In addition, the hardware configuration of the memory 37 and the processing circuit 39 in the bed control device 36 is the same as that in the first embodiment, and therefore their description will be omitted. Furthermore, the processing content executed by the calculation function 393 is also the same as that in the first embodiment, and therefore their description will be omitted. Furthermore, the processing content executed by the bed control function 391 is the same as that of the system control function 441 or the processing content executed by the control device 15 for the bed device 30 in the first embodiment, and therefore their description will be omitted.

[0083] The memory 37 stores programs related to the execution of the bed control function 391 and the calculation function 393. The memory 37 also stores predetermined thresholds, a reference map, and a body pressure map.

[0084] The bed control process in this embodiment will be described below with reference to Fig. 8. Fig. 8 is a flowchart showing an example of the procedure of the bed control process according to this embodiment. Steps S801 to S805 in Fig. 8 correspond to steps S601 to S605, respectively, in the flowchart shown in Fig. 6. Steps S806 and S807 in Fig. 8 correspond to steps S607 and S608, respectively, in the flowchart shown in Fig. 6. As a result, the processing contents of the bed control process in this embodiment conform to those of the first embodiment, and therefore a description thereof will be omitted.

[0085] The bed device 300 according to the second embodiment described above detects the body pressure of the subject P on the tabletop 33 on which the subject P is placed using a plurality of sensors 35, calculates the movement amount (single table movement amount) of the tabletop 33 to a predetermined imaging position based on the change in the body pressure of the subject P while the imaging device is imaging the subject P, and controls the movement of the support frame 34 that movably supports the tabletop 33 according to the movement amount. The effects of this embodiment are the same as those of the first embodiment except for the effect related to the exclusion function 446, and therefore will not be described again.

[0086] When the technical idea of the second embodiment is realized by a bed control method, the bed control method detects the body pressure of the subject P on a tabletop 33 on which the subject P is placed, calculates the amount of movement of the tabletop 33 to a predetermined imaging position based on changes in the body pressure of the subject P while the imaging device is imaging the subject P, and controls the movement of a support frame 34 that movably supports the tabletop 33 according to the calculated amount of movement. The procedures and effects of the bed control process executed by the bed control method are the same as those of the second embodiment, and therefore will not be described again.

[0087] According to at least one of the embodiments described above, it is possible to reduce (save) the time required for image generation.

[0088] Although the present disclosure has been described with reference to several embodiments, these embodiments are presented as examples of the principles and applications of the present disclosure and are not intended to limit the scope of the invention. These embodiments may be embodied in various other forms, and various omissions, substitutions, modifications, and combinations of embodiments may be made without departing from the spirit of the invention. These embodiments and their modifications are intended to be 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 appended claims. [Explanation of symbols]

[0089] 1 X-ray CT device 10 Mounting device 11 X-ray tube 12 X-ray detector 13 Rotating Frame 14 X-ray high voltage device 15 Control device 16 Wedge 17 Collimator 18 DAS (Data Acquisition System) 30 Bed Device 31 Foundation 32 Bed drive unit 33 Top plate 34 Support frame 35 Multiple Sensors 36 Bed control device 37 Memory 39 Processing circuit 40 Console device 41 memory 42 Display 43 Input Interface 44 Processing circuit 300 Bed Device 391 Bed Control Function 393 Calculation Function 441 System Control Functions 442 Pre-processing function 443 Reconstruction Processing Function 444 Image Processing Function 445 Calculation Function 446 Exclusion Function

Claims

1. an imaging device for imaging a subject; a plurality of sensors for detecting the body pressure of the subject; a top plate having the plurality of sensors and on which the subject can be placed; a support frame that movably supports the top plate; a calculation unit that calculates a movement amount of the tabletop to a predetermined imaging position based on a change in body pressure of the subject while the imaging device is imaging the subject; a control unit that controls the movement of the support frame in accordance with the movement amount; an exclusion unit that excludes images relating to changes in the body pressure of the subject from images to be displayed based on the changes in the body pressure of the subject; A medical image diagnostic device comprising:

2. The support frame is supported by a plurality of link mechanisms that can independently move the ends of the tabletop along the vertical direction. The medical image diagnostic apparatus according to claim 1 .

3. The plurality of link mechanisms are capable of tilting the tabletop. The medical image diagnostic apparatus according to claim 2 .

4. when the amount of movement exceeds a predetermined threshold, the control unit controls the movement of the support frame so as to move the tabletop in accordance with the amount of movement; the exclusion unit excludes an image relating to a change in body pressure of the subject from the display targets when the amount of movement exceeds a predetermined threshold. The medical image diagnostic apparatus according to claim 1 .

5. the plurality of sensors are weight sensors that detect a weight of the subject placed on the top plate or pressure sensors that detect a pressure on the top plate by the subject placed on the top plate. The medical image diagnostic apparatus according to claim 1 .

6. the imaging device is a gantry capable of scanning the subject; The medical image diagnostic apparatus according to claim 1 .

7. a plurality of sensors for detecting the body pressure of the subject; a top plate having the plurality of sensors and on which the subject can be placed; a support frame that movably supports the top plate; a calculation unit that calculates a movement amount of the tabletop to a predetermined imaging position based on a change in body pressure of the subject while an imaging device that images the subject is performing imaging of the subject; a bed control unit that controls the movement of the support frame according to the movement amount; A sleeper device comprising:

8. Detecting the body pressure of the subject on a tabletop on which the subject is placed; calculating a movement amount of the tabletop to a predetermined imaging position based on a change in body pressure of the subject while the imaging device is imaging the subject; controlling the movement of a support frame that movably supports the tabletop according to the amount of movement; A bed control method comprising:

Images