X-ray computed tomography apparatus

Abstract

To display a medical image generated by a scan in association with information on a posture of a subject in the scan.SOLUTION: An X-ray CT apparatus includes a reconstruction processing unit, a determination unit, and a display unit. The reconstruction processing unit reconstructs a medical image by executing reconstruction processing for raw data generated by scanning a subject. The processing circuitry determines a posture of the subject at the time of a scan based on an imaging condition in which an examination order concerning the scan is reflected. The display unit displays the medical image in association with the information on the posture.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The embodiments disclosed in the present specification and drawings relate to an X-ray computed tomography apparatus, a medical image display device, and a medical image display method. [Background technology]

[0002] Conventionally, a scan using an X-ray computed tomography (CT) apparatus is performed on a subject placed on a bed. At this time, the subject placed on the bed is generally in a supine position, a prone position, or the like. Data obtained by the scan is accompanied by additional information that is assumed to be in a supine position as the subject's position. Furthermore, when displaying medical images obtained by the X-ray CT apparatus, the subject's position is also assumed to be in a supine position.

[0003] Meanwhile, in recent years, X-ray CT systems capable of scanning subjects in a standing position have been developed. Furthermore, for example, by modifying the gantry of the X-ray CT system, it is possible to scan subjects in various positions, such as supine, standing, and sitting. In these cases, the position and posture information of the subject imaged must be newly stored, for example, by input from the operator, for the data obtained by the scan, as well as for the additional information and image display that were previously assumed to be in a supine position. In other words, conventional X-ray CT systems only store position information assuming a supine position, and do not store position information for positions other than supine, such as standing or sitting. In the case of X-ray CT systems capable of scanning subjects in a variety of positions, such as standing, supine, and sitting, there is a problem in that the operator cannot determine the position or posture in which the scan was performed when viewing the medical images generated by the CT system. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-121104 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 display a medical image generated by a scan in association with information about the subject's posture during the scan. 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] The X-ray computed tomography apparatus according to this embodiment includes a reconstruction processing unit, a determination unit, and a display unit. The reconstruction processing unit performs reconstruction processing on raw data generated by scanning a subject, and reconstructs a medical image. The determination unit determines the posture of the subject during scanning based on imaging conditions that reflect an examination order for the scan. The display unit displays the medical image in association with information related to the posture. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing an example of the arrangement of an X-ray CT apparatus according to the first embodiment. [Figure 2] FIG. 2 is a diagram showing an example of posture-related information according to the first embodiment. [Figure 3] FIG. 3 is a flowchart showing an example of a procedure of a posture display process according to the first embodiment. [Figure 4] FIG. 4 is a diagram showing an example of posture-related information displayed together with a list of scan plans according to the first embodiment. [Figure 5] FIG. 5 is a diagram showing an example of a medical image and posture-related information relating to a supine position displayed on a display according to the first embodiment. [Figure 6]FIG. 6 is a diagram showing an example of the first embodiment in which a plurality of medical images generated by a supine position scan are arranged in a schematic manner by series or volume and displayed so as to be selectable by the operator. [Figure 7] FIG. 7 is a diagram showing an example in which a plurality of medical images generated by upright scanning are arranged in a schematic manner by series or volume and displayed so as to be selectable by the operator, according to the first embodiment. [Figure 8] FIG. 8 is a diagram showing an example of the first embodiment in which a plurality of medical images generated by supine scans and upright scans are arranged in a schematic manner by series or volume and displayed so as to be selectable by the operator. [Figure 9] FIG. 9 is a diagram showing another example of posture-related information displayed together with a list of scan plans according to the first embodiment. [Figure 10] FIG. 10 is a diagram showing an example of a display mode in which reconstruction conditions different from those for a reconstructed medical image can be input according to the first embodiment. [Figure 11] FIG. 11 is a diagram showing an example of transformation information and posture-related information displayed together with a medical image and a posture transformation image according to the first embodiment. [Figure 12] FIG. 12 is a configuration diagram showing an example of the configuration of an X-ray CT system according to the second embodiment. [Figure 13] FIG. 13 is a diagram showing an example of past images and posture-related information (posture icons) displayed on a display of a medical image display device used as an image interpretation viewer according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of an X-ray computed tomography (CT) apparatus, a medical image display apparatus, and a medical image display method will be described with reference to the drawings. In the following embodiments, parts with the same reference numerals perform similar operations, and redundant explanations will be omitted as appropriate.

[0009] (First embodiment) FIG. 1 is a diagram showing an example of the configuration of an X-ray CT apparatus 1 according to a first embodiment. As shown in FIG. 1, the X-ray CT apparatus 1 includes a gantry 10, 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, and the direction perpendicular to the Z-axis and the X-axis is defined as the Y-axis. For convenience of explanation, multiple gantry devices 10 are depicted in FIG. 1, but the actual configuration of the X-ray CT apparatus 1 includes only one gantry device 10.

[0010] Although the X-ray CT apparatus 1 shown in FIG. 1 includes a bed device 30 so that the subject P can be scanned in a recumbent position, the X-ray CT apparatus 1 in the first embodiment does not necessarily have to include the bed device 30. For example, if the opening of the gantry device 10 in the X-ray CT apparatus 1 has a substantially cylindrical shape extending vertically, the subject P is scanned in an upright position, and the bed device 30 is not required. In this case, the X-ray CT apparatus is called an upright CT apparatus. Furthermore, the state of the gantry device 10 may be such that the rotation axis of the rotating frame 13 is changeable between the horizontal and vertical directions so that the subject P can be scanned regardless of whether the subject P is in a recumbent position or an upright position. In this case, the bed device 30 is retracted during the upright position and during the change in position depending on the change in the state of the gantry device 10, and is moved to the position shown in FIG. 1 during the recumbent position. Furthermore, the state of the gantry 10 may be such that the rotation axis of the rotating frame 13 is deformable between the horizontal and vertical directions so that scanning is possible even when the subject P is in an oblique position where the subject P is tilted obliquely relative to the horizontal plane. In this case, the bed 30 can be appropriately tilted without interfering with the gantry 10, for example, in accordance with the deformation of the state of the gantry 10. As described above, the X-ray CT apparatus 1 in this embodiment may have any type of gantry 10.

[0011] The gantry 10 and the bed 30 operate based on operations from an operator via the console 40 or operations from an operator via an operation unit provided on the gantry 10 or the bed 30. The gantry 10, the bed 30, and the console 40 are connected to each other by wire or wirelessly so as to be able to communicate with each other.

[0012] The gantry device 10 is an apparatus having an imaging system that irradiates an object P with X-rays and collects projection data from detection data of the X-rays that have passed through the object P. 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.

[0013] The X-ray tube 11 is a vacuum tube that generates X-rays by irradiating thermoelectrons 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 the thermoelectrons collide with the target. X-rays generated at the tube focus in the X-ray tube 11 pass through an X-ray radiation 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 thermoelectrons.

[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, a plurality of detector element rows, in which a plurality of detector elements are arranged in the channel direction along a single arc centered on the focal point of the X-ray tube 11. The X-ray detector 12 has, for example, a structure in which a plurality of the detector element rows are arranged in the slice direction (column direction, row direction). Note that there are various types of X-ray CT apparatus 1, such as 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 detector elements arrayed in a ring shape are fixed, and only the X-ray tube 11 rotates around the subject P, and any of these types can be applied to this embodiment.

[0015] 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 a plurality of 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. The grid is sometimes called a collimator (one-dimensional collimator or two-dimensional collimator). The photosensor array has the function of converting the amount of light from the scintillator into an electrical signal corresponding to the amount of light, and has a photosensor such as a photomultiplier tube (PMT). The X-ray detector 12 may be a direct conversion 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 X-ray detector. The X-ray detector 12 is an example of an X-ray detection unit.

[0016] The rotating frame 13 is an annular frame that supports the X-ray tube 11 and the X-ray detector 12 so as to face each other, and rotates the X-ray tube 11 and the X-ray detector 12 using a control device 15 (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 generator 14 and a DAS 18. The rotating frame 13 is rotatably supported by a non-rotating portion of the gantry device 10 (e.g., a fixed frame; not shown in FIG. 1). 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 in, for example, the non-rotating portion, 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.

[0017] The rotating frame 13 and the non-rotating portion are each provided with a non-contact or contact communication circuit, which allows communication between the unit supported by the rotating frame 13 and the non-rotating portion 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 portion of the gantry 10, and then transferred from the non-rotating portion to the console device 40 by the transmitter. Note that other communication methods may also be used, such as non-contact data transmission methods such as capacitive coupling and radio wave methods, as well as contact data transmission methods using slip rings and electrode brushes. The rotating frame 13 is an example of a rotating portion.

[0018] 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.

[0019] The control device 15 includes a processing circuit having a CPU (Central Processing Unit) and other components, and a drive mechanism including a motor and an actuator. The control device 15 receives input signals from an input interface attached to the console device 40 or the gantry device 10 and controls the operation of the gantry device 10 and the bed device 30. For example, the control device 15 receives input signals and controls the rotation of the rotating frame 13, the tilt of the gantry device 10, and the operation of the bed device 30 and the tabletop 33. The control of tilting the gantry device 10 is realized by the control device 15 rotating the rotating frame 13 around an axis parallel to the X-axis direction based on tilt angle information input through an input interface attached to the gantry device 10. The control device 15 may be provided in the gantry device 10 or the console device 40. The control device 15 may be configured to directly incorporate a program into the circuitry of its processor instead of storing the program in its memory. The control device 15 is an example of a control unit.

[0020] 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.

[0021] 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.

[0022] The DAS 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 first processing circuit 36. The detection data may also be referred to as pure raw data. The DAS 18 is also an example of a data acquisition unit.

[0023] The bed device 30 is a device on which the subject P to be scanned is placed and moved, and includes a base 31, a bed driving device 32, a top plate 33, and a support frame 34. The base 31 is a housing that supports the support frame 34 so that it can move in the vertical direction. The bed driving device 32 is a motor or actuator that moves the top plate 33, on which the subject P is placed, in the longitudinal direction of the top plate 33. The top plate 33, which is provided on the upper surface of the support frame 34, is a plate on which the subject P is placed. Note that the bed driving device 32 may move the support frame 34 in the longitudinal direction of the top plate 33 in addition to the top plate 33.

[0024] 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.

[0025] The memory 41 is realized by, for example, a random access memory (RAM), a semiconductor memory element such as a flash memory, a hard disk, an optical disk, or a solid state drive (SSD). The memory 41 stores, for example, detection data output from the DAS 18, projection data generated by the preprocessing function 442, medical image data reconstructed by the reconstruction processing function 443, image data processed by the image processing function 444, and imaging conditions for scanning the subject P. The medical image data is, for example, three-dimensional CT image data, and is also referred to as reconstructed image data or volume data. Furthermore, data before preprocessing by the preprocessing function 442 (detection data or pure raw data) and projection data are collectively referred to as raw data. In other words, the raw data may be pure raw data or projection data. The memory 41 stores programs related to the execution of the system control function 441, the preprocessing function 442, the reconstruction processing function 443, the image processing function 444, the determination function 445, and the auxiliary functions 446 executed by the processing circuitry 44. The memory 41 is an example of a storage unit.

[0026] 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 graphical user interface (GUI) for receiving various operations from the operator, such as setting imaging conditions and retrying reconstruction. For example, the display 42 may be a liquid crystal display (LCD), a cathode ray tube (CRT), an organic electroluminescence display (OLED), a plasma display, or any other display, as appropriate. The display 42 may also be provided on the gantry device 10. The display 42 may also be a desktop type, or may be configured as a tablet terminal or the like capable of wireless communication with the console device 40 main body. The display 42 is an example of a display unit.

[0027] 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 imaging conditions for collecting projection data, 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. It may also be performed simultaneously by both the console device 40 and the workstation. The post-processing defined here refers to processing of images reconstructed by the reconstruction processing function 443. Examples include multi-planar reconstruction (MPR) display of medical images and rendering of volume data. The input interface 43 may be, for example, a mouse, keyboard, trackball, switch, button, joystick, touchpad, touch panel display, etc., as appropriate.

[0028] 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. The input interface 43 is an example of an input unit.

[0029] 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, a processor 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 determination function 445, and an additional function 446 by a processor that executes a program loaded in the 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.

[0030] 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 system control function 441 is an example of a control unit.

[0031] The pre-processing function 442 generates 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. As described above, data before pre-processing is called pure raw data, and data after pre-processing is called projection data. The pre-processing function 442 is an example of a pre-processing unit.

[0032] The reconstruction processing function 443 performs reconstruction processing on raw data generated by scanning the subject P to reconstruct a medical image. Specifically, the reconstruction processing function 443 performs reconstruction processing using a filtered back projection (FBP) method or the like on the projection data generated by the pre-processing function 442 to generate medical image data. The reconstruction processing includes various types of processing such as various correction processes such as scattering correction and beam hardening correction, and application of a reconstruction function under reconstruction conditions. The reconstruction processing function 443 stores the reconstructed medical image data in the memory 41. The reconstruction processing function 443 is an example of a reconstruction processing unit.

[0033] The image processing function 444 converts medical image data 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 an operator via the input interface 43. Note that the generation of three-dimensional image data may be performed directly by the reconstruction processing function 443. The image processing function 444 is an example of an image processing unit.

[0034] The determination function 445 determines the posture of the subject P during scanning based on imaging conditions that reflect the examination order for the scan. The determination function 445 may determine the imaging conditions based on an examination order output from a radiology information system (hereinafter referred to as a RIS (Radiology Information System)) or a hospital information system (hereinafter referred to as a HIS (Hospital Information System)). For example, if the posture of the subject P during scanning is described in the examination order, the determination function 445 determines the imaging conditions using the posture described in the examination order. The posture of the subject P refers to, for example, the body position of the subject P during scanning, such as an upright position, a supine position, or a sitting position. The posture of the subject P is not limited to the above-mentioned body positions, and may be, for example, an oblique position in which the tabletop 33 is inclined from the horizontal plane (hereinafter referred to as an oblique position). The imaging conditions, which are also referred to as an imaging protocol, describe settings for each scan, such as dose, tube voltage, tube current, scan speed, slice thickness, and imaging mode, as well as phases indicating the imaging order for performing a pre-scan for setting the imaging range and a main scan, such as a helical scan or step-and-shoot scan. The imaging mode corresponds to various scan modes, such as a helical scan (H), a step-and-shoot scan (S&S), a scan-and-view (S&V), and a dynamic scan. The imaging conditions may include posture information written in the examination order. The determination function 445 may determine the imaging conditions and the postures according to an operator's instruction via the input interface 43. The determination function 445 is an example of a determination unit. The posture of the subject P during the scan may be estimated by the processing circuitry 44 by comparing a combination of various items related to the posture in the imaging conditions with a correspondence table of postures corresponding to the combination.

[0035] The auxiliary function 446 attaches information about the posture determined by the determination function 445 (hereinafter referred to as posture-related information) to the raw data and medical images. The posture-related information includes, for example, character strings indicating the position and posture of the subject P during scanning, icons (hereinafter referred to as posture icons) that schematically show these character strings, angle information relative to the horizontal plane in supine, standing, oblique, etc., and information indicating the direction of gravity. The auxiliary function 446 refers to the posture-related information when transmitting medical images according to posture to a server of a medical image management system (hereinafter referred to as PACS (Picture Archiving and Communication Systems)) or when searching for medical images according to posture. The auxiliary function 446 is an example of an auxiliary unit.

[0036] In the X-ray CT apparatus 1 according to this embodiment configured as described above, a process of displaying a medical image generated by a scan in association with information relating to the posture of the subject P during the scan (hereinafter referred to as posture display process) will be described with reference to Figures 2 to 11. Prior to execution of the posture display process, the memory 41 stores posture-related information.

[0037] FIG. 2 is a diagram showing an example of posture-related information PRI. As shown in FIG. 2, the memory 41 stores character strings, posture icons, and the like that schematically and visually indicate the posture and body position of the subject P during scanning. The posture icons that schematically and visually indicate the posture and body position of the subject P during scanning may be expressed using different hues (different hatching in FIG. 2) according to the posture and body position of the subject P. For example, green for a supine position, red for an upright position, and yellow for a sitting position. The tip of the arrow AR in FIG. 2 indicates the head of the subject P, and the horizontal line HL located below the arrow indicates the floor. Note that instead of the horizontal line HL indicating the floor, a symbol indicating the vertical direction may be configured as the posture icon together with an arrow indicating the posture of the subject P. Furthermore, the visual symbol PG that visually and schematically indicates the human body as the posture of the subject P may be displayed together with the horizontal line HL indicating the floor and a symbol indicating the vertical direction. Furthermore, the posture-related information PRI is not limited to the example shown in FIG. 2, and may be expressed by various omissions, substitutions, modifications, combinations, etc., depending on the posture of the subject P, as appropriate.

[0038] FIG. 3 is a flowchart illustrating an example of a procedure for the attitude display process.

[0039] (Attitude display processing) (Step S301) The determination function 445 determines the imaging conditions for the subject P based on the examination order output from the RIS or HIS. Specifically, the determination function 445 determines the imaging conditions according to the examination order at the instruction of the operator via the input interface 43. In determining the imaging conditions, the posture, position, etc. of the subject P at the time of scanning may be input at the instruction of the operator via the input interface 43. In addition, if the posture, position, etc. of the subject P at the time of performing the scan are described in the examination order, the determination function 445 may determine the imaging conditions using the posture, position, etc. described in the examination order. At this time, the display 42 displays the determined imaging conditions together with information on the posture in the examination order.

[0040] (Step S302) The determination function 445 determines the posture of the subject P during the scan based on the imaging conditions for the scan determined in step S301. Specifically, if the scan using the imaging conditions is a scan in an upright position (hereinafter referred to as an upright scan), the determination function 445 determines that the posture of the subject P is upright. Also, if the scan using the imaging conditions is a scan in a prone position (hereinafter referred to as a prone scan), the determination function 445 determines that the posture of the subject P is prone. Also, if the scan using the imaging conditions is a scan in a sitting position (hereinafter referred to as a sitting scan), the determination function 445 determines that the posture of the subject P is sitting. If the scan using the imaging conditions is a scan in an oblique position (hereinafter referred to as an oblique scan), the determination function 445 determines that the posture of the subject P is oblique.

[0041] The determination function 445 may execute language analysis processing on the examination order to detect the posture and body position described in the examination order and determine the posture of the subject P when the scan is performed. The determination function 445 may also automatically determine the posture of the subject P based on outputs from external devices such as various cameras installed in the examination room where the X-ray CT apparatus 1 is installed, mechanical angle detection by an acceleration sensor or the like installed in the gantry device 10, or internal information related to positioning imaging (positioning scan) for the subject P. The display 42 displays the imaging conditions together with information related to the posture.

[0042] Fig. 4 is a diagram showing an example of posture-related information PRI displayed together with a list PL of scan plans. A scan plan is, for example, an arrangement of imaging conditions for each scan (tube voltage 802, tube current 803, scan time 804, etc.) for each scan, for each scan identification number 801, and corresponds to the rows in the list PL shown in Fig. 4. In this case, a posture icon is displayed in the item of body position information as posture-related information PRI in each row of the list PL.

[0043] As shown in FIG. 4, an instruction to change the posture icon RI may be input via the input interface 43. The instruction to change the posture icon RI is, for example, an operation such as clicking on the posture icon RI. At this time, in response to an instruction to change the posture to another posture in the posture information displayed together with the imaging conditions, the determination function 445 determines the imaging conditions corresponding to the other posture using the other posture. That is, when the posture icon is changed to another posture icon, the determination function 445 changes the imaging conditions to those corresponding to the other posture icon based on the other posture icon and the examination order. Next, the display 42 displays the changed imaging conditions together with information about the other posture (other posture icon).

[0044] (Step S303) The system control function 441 executes a scan on the subject P based on the imaging conditions. The system control function 441 stores raw data generated by the execution of the scan in the memory 41.

[0045] (Step S304) The reconstruction processing function 443 reconstructs a medical image based on the raw data. The reconstruction processing function 443 stores the reconstructed medical image in the memory 41.

[0046] (Step S305) The additional function 445 attaches posture-related information to the raw data generated by the scan in step S303 and the medical image reconstructed in step S304. Specifically, the additional function 445 reads posture-related information corresponding to the posture determined by the determination function 445 from the memory 41, and attaches the read posture-related information to the raw data and the medical image.

[0047] (Step S306) The display 42 displays the medical image in association with the posture-related information PRI. For example, the display 42 uses the posture-related information PRI to display the medical image in a manner that allows the type of posture (supine, standing, sitting, oblique, etc.) to be identified. If the gantry 10 is deformable, that is, if the X-ray CT apparatus 1 is an X-ray CT apparatus that can scan a subject in either a standing or supine position (hereinafter referred to as a universal CT apparatus), the display 42 may display the rotation angle of the gantry 10 as angle information, which is posture-related information.

[0048] Specifically, the display 42 displays at least one of the following: when the determined posture is an upright position, information indicating the upright position in the posture-related information PRI is displayed together with the medical image; when the determined posture is a supine position, information indicating the supine position in the posture-related information PRI is displayed together with the medical image; and when the determined posture is a sitting position, information indicating the sitting position in the posture-related information PRI is displayed together with the medical image. For example, the display 42 does not display posture-related information for a scan performed in a standard supine position, but displays posture-related information for a scan performed in a standing or sitting position. When information indicating the direction of gravity is displayed as posture-related information, it may be presented as information substantially equivalent to information indicating the posture of the subject P. However, it is impossible to distinguish between a standing position and a sitting position using information indicating the direction of gravity. Therefore, in a situation where the subject's state changes between a standing position and a sitting position, for example, in a universal CT scanner, displaying the posture-related information PRI shown in FIG. 2 instead of information indicating the direction of gravity is important. Display examples of posture-related information PRI are described below with reference to FIGS. 5 to 11.

[0049] Fig. 5 is a diagram showing an example of a medical image MI and posture-related information DI relating to the supine position displayed on the display 42. As shown in Fig. 5, since the medical image MI was generated by a supine position scan, the display 42 displays information DI indicating the supine position as posture-related information together with the medical image MI.

[0050] Figure 6 shows an example in which multiple medical images generated by supine scans are arranged in a schematic format by series or volume and displayed so that they can be selected by the operator. As shown in Figure 6, a typical medical image AI is displayed in axial cross section as posture-related information to make it easier for the operator to visually recognize the supine scan.

[0051] FIG. 7 shows an example in which multiple medical images generated by upright scans are arranged in a schematic format by series or volume and displayed so that they can be selected by the operator. As shown in FIG. 7, a representative medical image CI is displayed in a coronal plane as posture-related information so that the operator can easily visually recognize the upright scan. Also, as shown in FIG. 7, a representative medical image SI is displayed in a sagittal plane as posture-related information so that the operator can easily visually recognize the upright scan. Note that the representative image identifiable as an upright scan may be either a coronal plane or a sagittal plane.

[0052] FIG. 8 shows an example in which multiple medical images generated by supine and upright scans are arranged in a schematic format by series or volume and displayed for selection by the operator. As shown in FIG. 8, a representative medical image CI is displayed in a coronal plane as posture-related information to facilitate visual recognition of upright scans. Also, as shown in FIG. 8, a representative medical image AI is displayed in an axial plane as posture-related information to facilitate visual recognition of supine scans. Additionally, the scan icons (3 / Vol. and 4 / BM) display posture-related information for each scan as a posture icon, along with a representative medical image corresponding to the associated scan. The posture icon RI in FIG. 8 indicates a supine scan, as shown in FIG. 2. The posture icon SI in FIG. 8 indicates an upright scan, as shown in FIG. 2.

[0053] 9 is a diagram showing another example of posture-related information PRI displayed together with the scan plan list PL. As shown in FIG. 9, the display 42 displays an icon SMI (e.g., H, S&S, S&V) indicating an imaging mode for each identification number 801 near the scan plan list PL. For example, the display 42 displays a list in the first display area 1DA in which icons SMI indicating imaging modes for scans and imaging conditions are arranged for each scan. The display 42 also highlights the scan plan selected by the operator in the list PL. At this time, the display 42 displays medical images corresponding to the selected scan plan in the second display area 2DA. The display 42 also displays posture-related information PRI corresponding to the scan in the first display area adjacent to the icon SMI indicating the imaging mode.

[0054] In FIG. 9, the scan plan with identification number "1" is selected, so the scan plan corresponding to the identification number "1" is highlighted, and a representative medical image PMI for the scan plan with identification number "1" is displayed in the second display area 2DA. Also, as shown in FIG. 9, the imaging mode for the scan plan with identification number "1" is helical scan, so an icon "H" indicating the imaging mode is displayed as the icon for that scan plan near the scan plan with identification number "1" in the first display area. Furthermore, the display 42 displays the posture-related information RI corresponding to the selected scan in the first display area 1DA adjacent to the icon "H" indicating the imaging mode. Note that the display 42 may display the posture-related information RI together with the medical image PMI in the second display area 2DA.

[0055] FIG. 10 is a diagram showing an example of a display mode in which reconstruction conditions different from those for a reconstructed medical image can be input. This display mode corresponds to a display screen for a reconstruction retry in which reconstruction is performed again by changing the reconstruction conditions. When an instruction for a reconstruction retry is input by an operator via the input interface 43, the display 42 displays a display mode such as that shown in FIG. 10. As shown in FIG. 10, the display 42 displays an already reconstructed medical image MI together with posture-related information DI indicating the supine position on the input screen for the reconstruction conditions for the reconstruction retry. Also, as shown in FIG. 10, the display 42 displays posture-related information RI indicating the supine position in the area IA where the reconstruction conditions are input and the image selection area SA.

[0056] The image processing function 444 performs conversion processing between multiple medical images corresponding to different postures. For example, the image processing function 444 converts a medical image into a posture-converted image corresponding to a different posture, different from the posture determined in step S302, based on the medical image reconstructed in step S304 and the posture. The image conversion processing is realized, for example, by multiple image filters generated by training a deep convolutional neural network (DCNN) that pairs images of standing and sitting positions, standing and lying positions, and sitting and lying positions. That is, the position of organs in medical images changes (hereinafter referred to as organ sagging) depending on the posture and position of the subject P during scanning. For example, the position of organs in a medical image reconstructed by scanning in an upright position (hereinafter referred to as an upright image) sags due to gravity compared to the position of organs in a medical image reconstructed by scanning in a lying position (hereinafter referred to as a lying image). The plurality of image filters correspond to filters that realize reproduction of organ sagging in medical images or reduction of organ sagging.

[0057] The image processing function 444 inputs medical images into multiple image filters to convert between standing images and lying images, between medical images reconstructed by scanning in a sitting position (hereinafter referred to as sitting images) and lying images, and between standing images and sitting images. For example, the image processing function 444 inputs the lying image reconstructed in step S304 into an image filter that converts the lying image into a standing image, thereby generating a posture-converted image equivalent to the standing image. The display 42 displays the posture-converted image together with information indicating that the posture-converted image has been converted from the medical image (hereinafter referred to as conversion information) and information related to other postures (posture-related information).

[0058] Fig. 11 is a diagram showing an example of conversion information and posture-related information displayed together with a medical image MI and a posture-transformed image PTI. The imaging position shown in Fig. 11 indicates the posture of the subject P when a scan is performed on the subject. The image position indicates the posture related to the displayed medical image and posture-transformed image. The imaging position and image position correspond to the posture-related information. The character string "(converted)" in Fig. 11 indicates that the posture-transformed image PTI has been converted from the medical image MI.

[0059] The medical image displayed in step S306 is transmitted to, for example, a PACS server in response to an instruction from the operator via the input interface 43. At this time, since the medical image is accompanied by posture-related information, the operator can transmit the medical image to the PACS server in accordance with the posture and position of the subject P at the time of scanning. Furthermore, the system control function 441 searches for medical images linked to the posture-related information in accordance with the posture and position of the subject P at the time of scanning in response to an instruction from the operator via the input interface 43. The display 42 displays the medical image identified by the search together with the posture-related information and the imaging conditions. This allows the operator to easily refer to, for example, the imaging conditions in accordance with the posture and position of the subject at the time of scanning. Therefore, the X-ray CT apparatus 1 can improve the efficiency and throughput of examinations of subjects.

[0060] The X-ray CT apparatus 1 according to the first embodiment described above reconstructs medical images by performing a reconstruction process on raw data generated by scanning the subject P, determines the posture of the subject P at the time of the scan based on the imaging conditions for the scan, and displays the medical images in association with information about the posture. For example, the X-ray CT apparatus 1 displays medical images in a manner that allows the type of posture (such as supine, standing, sitting, or oblique posture) to be identified. Specifically, the X-ray CT apparatus 1 performs at least one of the following: when the posture is upright, information indicating the standing position is displayed together with the medical image; when the posture is supine, information indicating the supine position is displayed together with the medical image; and when the posture is sitting, information indicating the sitting position is displayed together with the medical image. As a result, when a reconstructed medical image is displayed, the X-ray CT apparatus 1 allows the operator to easily determine the posture in which the scan for the medical image was performed without accessing detailed information (such as properties) of the medical image. This makes it possible to transfer medical images to a PACS server or the like according to the posture of the subject P during scanning, and to easily grasp the posture and position of the subject P related to the medical images during interpretation. As a result, the X-ray CT apparatus 1 can improve the efficiency of examinations and interpretations.

[0061] Furthermore, the X-ray CT apparatus 1 according to the first embodiment displays a list in the first display area, in which icons indicating imaging modes and imaging conditions for each scan are arranged for each scan. A medical image corresponding to a scan selected from the list is displayed in the second display area. Information about the posture corresponding to the scan is displayed adjacent to the icon in the first display area. Furthermore, the X-ray CT apparatus 1 displays a medical image together with information about the posture in a display mode that allows input of reconstruction conditions different from those for the medical image. Therefore, the X-ray CT apparatus 1 allows the operator to easily determine the posture in which the scan for the medical image was performed without confusion when displaying the scan plan list PL or on the input screen for reconstruction retries, without accessing detailed information about the medical image. Therefore, the X-ray CT apparatus 1 can improve the efficiency of examinations and post-processing, such as reconstruction retries.

[0062] Furthermore, according to the X-ray CT apparatus 1 of the first embodiment, when the posture is specified in the examination order for the subject P, the imaging conditions are determined using the specified posture, and the determined imaging conditions are displayed together with information about the posture in the examination order. Furthermore, according to the present X-ray CT apparatus 1, in response to an instruction to change the posture to another posture in the posture information displayed together with the imaging conditions, the imaging conditions are changed to those corresponding to the other posture using the other posture, and the changed imaging conditions are displayed together with information about the other posture. As a result, according to the present X-ray CT apparatus 1, the posture of the subject P during the scan can be easily grasped before the scan is performed, and the imaging conditions can be easily changed. For example, if an examination order is received to scan the subject P in an upright position, and the subject P cannot be scanned in an upright position due to old age, injury, fatigue, or the like, the operator can easily change the imaging conditions to scan the subject P in a sitting or supine position. Furthermore, even if an examination order is received to scan the subject P in a supine position, and the subject P is in good health and therefore the scan is to be performed in a more convenient upright position, the imaging conditions can be easily changed. As described above, the X-ray CT apparatus 1 can improve the efficiency of examination.

[0063] Furthermore, the X-ray CT apparatus 1 according to the first embodiment converts a medical image into a posture-converted image corresponding to the other posture based on a posture different from the posture and the medical image, and displays the posture-converted image together with information indicating that the posture-converted image has been converted from the medical image and information regarding the other posture. Therefore, when a reconstructed medical image is displayed, the X-ray CT apparatus 1 allows the operator to easily determine the relationship between the displayed medical image and the posture and position of the subject P without accessing detailed information about the medical image (such as properties indicating information about settings and attributes). This allows the X-ray CT apparatus 1 to transfer medical images to a PACS server or the like according to the posture of the subject P, thereby improving examination efficiency.

[0064] Furthermore, according to the X-ray CT apparatus 1 of the first embodiment, posture-related information is attached to raw data and medical images. As a result, the X-ray CT apparatus 1 can easily search for and transfer medical images according to posture-related information, such as standing, lying, or sitting, thereby improving examination efficiency.

[0065] (Second embodiment) The second embodiment is directed to realizing a process of adding posture-related information to a past medical image by using a medical image display device. Note that the medical image processing device can also realize a posture display process.

[0066] FIG. 12 is a configuration diagram showing an example of the configuration of an X-ray CT system 2. The X-ray CT system 2 includes an X-ray CT device 3 and a medical image display device 5. The X-ray CT device 3 corresponds to, for example, an existing X-ray CT device that does not have the decision function 445 and the additional function 446 in the X-ray CT device 1 shown in FIG. 1. Therefore, a description of the X-ray CT device 3 will be omitted. The medical image display device 5 may be incorporated into, for example, a PACS or HIS, or may be realized as a terminal device connected to a PACS server or an HIS server. For example, the medical image display device 5 may function as an interpretation terminal.

[0067] The medical image display device 5 has a memory 51, a display 52, an input interface 53, and a processing circuitry 54. Data communication between the memory 51, the display 52, the input interface 53, and the processing circuitry 54 is performed, for example, via a bus (BUS). The hardware configurations of the memory 51, the display 52, the input interface 53, and the processing circuitry 54 are similar to those of the memory 41, the display 42, the input interface 43, and the processing circuitry 44 in the first embodiment, respectively, and therefore description thereof will be omitted. Furthermore, the processing contents of the multiple functions in the processing circuitry 44 are similar to those in the first embodiment, and therefore processing contents that differ from those in the first embodiment will be described.

[0068] The memory 51 stores a plurality of medical images (hereinafter referred to as past images) that have been generated in the past by the X-ray CT device 3. The past images are accompanied by additional information such as version information of the software in the X-ray CT device 3 that was used to generate the past images, the model number of the X-ray CT device 3, and the name of the X-ray CT device 3.

[0069] The determination function 445 determines the posture of the subject P when the scan for the past image was performed based on the supplementary information. For example, if the version information is older than a predetermined version, the determination function 445 determines information about "supine position" as the posture. Note that the determination function 445 may determine information about "supine position" as the posture based on the model number of the X-ray CT device 3, the name of the X-ray CT device 3, or the like. Furthermore, if the determination function 445 cannot determine the posture based on the supplementary information, it determines "unknown" as the posture of the subject P when the scan for the past image was performed.

[0070] The attachment function 446 attaches to the past image the posture-related information relating to the posture determined by the determination function 445. Note that the attachment function 446 may attach posture-related information to the past image all at once as long as it can be attached.

[0071] The display 52 displays the past images in association with the posture-related information PRI. For example, when interpreting medical images or past images, the display 52 displays the medical images or past images in association with the posture-related information PRI. If the posture-related information attached to the past images is "unknown," the display 52 may display "unknown" or a symbol (?) indicating the unknown as posture-related information together with the past images. Furthermore, for example, if no universal CT scanners or upright CT scanners are connected to the in-hospital network or hospital cooperation network to which the medical image display device 5 is connected, the display 52 may not display the posture-related information when displaying medical images and past images.

[0072] Fig. 13 is a diagram showing an example of a past image PI and posture-related information (posture icon RI) displayed on the display 52 of the medical image display device 5 used as an interpretation viewer. As shown in Fig. 13, the posture icon RI is displayed near the medical image displayed during interpretation.

[0073] According to the medical image display device 5 of the second embodiment described above, the posture of the subject P at the time of performing the scan is determined based on the imaging conditions for the scan of the subject P, and the medical image reconstructed by the scan is displayed in association with information about the posture. As a result, when the reconstructed medical image is displayed, the operator can easily determine, without confusion, in what posture the scan for the medical image was performed without accessing detailed information (properties, etc.) of the medical image, which can improve, for example, the efficiency of image interpretation. The procedure and effects of the posture display process, excluding the execution of the scan, are the same as those of the first embodiment, and therefore will not be described again.

[0074] When the technical idea of ​​the embodiment is realized in a medical image display method, the medical image display method determines the posture of the subject P when the scan is performed based on imaging conditions that reflect the examination order for the scan on the subject P, and displays the medical image reconstructed by the scan in association with information about the posture. The procedure and effect of the posture display process executed by the medical image processing method are the same as those in the first embodiment, so a description thereof will be omitted.

[0075] When the technical concept of the embodiment is realized by a medical image display program, the medical image display program causes a computer to determine the posture of the subject P at the time of scanning based on imaging conditions that reflect an examination order for the scan, and to display the medical image reconstructed by the scan on the display 52 in association with posture information. For example, posture display processing can be realized by installing the medical image display program in various server devices (processing devices) related to medical image display processing and expanding the program in memory. In this case, a program that can cause a computer to execute the method can also be stored in a storage medium such as a magnetic disk (e.g., hard disk), optical disk (e.g., CD-ROM, DVD), or semiconductor memory and distributed. The processing procedures and effects of the medical image display program are similar to those of the first and second embodiments, and therefore will not be described again.

[0076] According to at least one of the embodiments described above, it is possible to display a medical image generated by a scan in association with information relating to the posture of the subject during the scan.

[0077] Although several embodiments have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations of embodiments can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0078] 1 X-ray CT device 2 X-ray CT systems 3 X-ray CT device 5 Medical image display devices 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 40 Console device 41 memory 42 Display 43 Input Interface 44 Processing circuit 51 memory 52 Display 53 Input Interface 54 Processing circuit 441 System Control Functions 442 Pre-processing function 443 Reconstruction Processing Function 444 Image Processing Function 445 Decision Function 446 Additional Functions

Claims

1. a reconstruction processing unit that performs reconstruction processing on raw data generated by scanning a subject to reconstruct a medical image; a determination unit that determines a posture of the subject during scanning based on imaging conditions that reflect an examination order for the scan; a display unit that displays the medical image in association with information about the posture; An X-ray computed tomography apparatus comprising:

2. The display unit If the posture is an upright position, displaying information indicating the upright position together with the medical image; If the posture is a supine position, displaying information indicating the supine position together with the medical image; and if the posture is a sitting position, displaying information indicating the sitting position together with the medical image.

2. The X-ray computed tomography apparatus according to claim 1.

3. the display unit displays the medical image in a manner that allows the type of posture to be identified.

3. An X-ray computed tomography apparatus according to claim 1.

4. The display unit a list in which icons indicating imaging modes for the scans and the imaging conditions are arranged for each scan is displayed in a first display area; displaying a medical image corresponding to a scan selected in the list in a second display area; displaying information about the posture corresponding to the scan in the first display area adjacent to the icon; 4. An X-ray computed tomography apparatus according to claim 1.

5. the display unit displays the medical image together with information about the posture in a display mode in which a reconstruction condition different from the reconstruction condition for the medical image can be input.

5. An X-ray computed tomography apparatus according to claim 1.

6. when the posture is described in the examination order for the subject, the determination unit determines the imaging conditions using the described posture; the display unit displays the determined imaging conditions together with information on the posture in the examination order.

6. An X-ray computed tomography apparatus according to claim 1.

7. the determination unit, in response to an instruction to change the posture to another posture in information about the posture displayed together with the photographing condition, changes the photographing condition to a photographing condition corresponding to the other posture by using the other posture; the display unit displays the changed imaging conditions together with information about the other posture.

7. An X-ray computed tomography apparatus according to claim 6.

8. an image processing unit that converts the medical image into a posture-converted image corresponding to another posture different from the posture, based on the medical image and another posture different from the posture; the display unit displays the posture transformation image together with information indicating that the posture transformation image has been transformed from the medical image and information regarding the other posture.

8. An X-ray computed tomography apparatus according to claim 1.

9. an attachment unit that attaches information about the posture to the raw data and the medical image; 9. An X-ray computed tomography apparatus according to claim 1.

10. a determination unit that determines a posture of the subject during scanning based on imaging conditions that reflect an examination order for scanning the subject; a display unit that displays the medical image reconstructed by the scan in association with information about the posture; A medical image display device comprising:

11. determining a posture of the subject during scanning based on imaging conditions that reflect an examination order for scanning the subject; displaying a medical image reconstructed by the scan in association with information about the posture; A medical image display method comprising:

Images