X-ray CT apparatus, display method, and display program

Abstract

To reduce a physical burden related to imaging of a subject.SOLUTION: An X-ray CT apparatus includes a scanner, a stand, an acquisition unit, a generation unit, and a display control unit. The scanner has an opening into which a subject is inserted. The stand supports the scanner to be movable in a vertical direction. The acquisition part acquires an internal image obtained by photographing the inside of the opening from a camera. The generation part generates a visualization image visualizing the inside of the opening viewed from a visual line direction toward the inside of the opening on the basis of the internal image. The display control unit displays the visualized image on a display unit.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The embodiments disclosed in the present specification and drawings relate to an X-ray CT apparatus, a display method, and a display program. [Background technology]

[0002] X-ray CT (Computed Tomography) devices can capture images of subjects in various postures. X-ray CT devices can capture images of subjects in a standing or sitting position by moving a horizontally placed scanner vertically.

[0003] Conventionally, upright X-ray CT scanners project laser light from a projector at the height of the imaging cross section (or X-ray path) inside the scanner aperture. The technician checks the laser light projected onto the subject and adjusts the height of the imaging cross section to the desired height on the subject.

[0004] However, the technician must view the laser light projected onto the subject from below the opening, which places a great physical burden on the technician as he or she must peer into the opening while crouching (semi-crouching). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-62126 Summary of the Invention [Problem to be solved by the invention]

[0006] One of the problems to be solved by the embodiments disclosed in this specification and the drawings is to reduce the physical burden on a subject associated with imaging. 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 the configurations shown in the embodiments described below can also be positioned as other problems. [Means for solving the problem]

[0007] An X-ray CT apparatus according to an embodiment includes a scanner, a stand, an acquisition unit, a generation unit, and a display control unit. The scanner has an opening into which a subject is inserted. The stand supports the scanner so that it can move vertically. The acquisition unit acquires an internal image of the inside of the opening from a camera. The generation unit generates a visualized image that visualizes the inside of the opening as viewed from a line of sight toward the inside of the opening, based on the internal image. The display control unit displays the visualized image on a display unit. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram showing the overall configuration of an X-ray CT apparatus according to a first embodiment. [Figure 2] FIG. 2 is a top view showing the configuration of the gantry according to the first embodiment. [Figure 3] FIG. 2 is a flowchart showing the operation of the X-ray CT apparatus according to the first embodiment. [Figure 4] FIG. 2 is an explanatory diagram showing a display example of a visualized image according to the first embodiment. [Figure 5] FIG. 10 is a top view showing the configuration of the gantry according to the second embodiment. [Figure 6] FIG. 10 is an explanatory diagram showing a display example of a visualized image according to the second embodiment. [Figure 7] FIG. 10 is a top view showing the configuration of a gantry according to a third embodiment. [Figure 8] FIG. 10 is a top view showing the configuration of a gantry according to a fourth embodiment. [Figure 9] FIG. 11 is a top view showing the configuration of a gantry according to a fifth embodiment. [Figure 10] FIG. 11 is a flowchart showing the operation of the X-ray CT apparatus according to the fifth embodiment. [Figure 11] FIG. 13 is a top view showing the configuration of a gantry according to a sixth embodiment. [Figure 12] FIG. 13 is a flowchart showing the operation of the X-ray CT apparatus according to the sixth embodiment. [Figure 13] FIG. 13 is an explanatory diagram showing a display example of a visualized image according to the sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, each embodiment will be described with reference to the drawings. Parts with the same reference numerals are considered to be the same, and redundant description will be omitted where appropriate.

[0010] (First embodiment) 1 is a schematic diagram showing the overall configuration of an X-ray CT apparatus 1 according to the first embodiment. The X-ray CT apparatus 1 irradiates an object with X-rays from an X-ray tube and detects the irradiated X-rays with an X-ray detector. The X-ray CT apparatus 1 generates a CT image of the object based on the output from the X-ray detector.

[0011] The X-ray CT apparatus 1 has a gantry 2 and a console 3. For example, the gantry 2 is installed in an examination room, and the console 3 is installed in an operation room adjacent to the examination room. The gantry 2 and the console 3 are connected to each other by wire or wirelessly so that they can communicate with each other. The gantry 2 has a mechanism for performing X-ray computed tomography (hereinafter referred to as CT imaging) on ​​a subject in a supine, standing, or sitting position. The console 3 is a computer that controls the gantry 2.

[0012] (Configuration of the Mount) The mount 2 has a scanner 21 and two stands 22. The scanner 21 performs X-ray CT imaging. The scanner 21 is a substantially cylindrical structure having an opening OP formed therein. The opening OP is also called a "bore."

[0013] A three-dimensional Cartesian coordinate system is defined for the pedestal 2. The Cartesian coordinate system has an X-axis, a Y-axis, and a Z-axis that are perpendicular to each other. The X-axis direction is a direction (first horizontal direction) that is parallel to the floor surface FL and passes through the two stands 22. The Y-axis direction is a direction (second horizontal direction) that is parallel to the floor surface FL and perpendicular to the X-axis. The Z-axis direction is a direction (vertical direction) that is perpendicular to the floor surface FL.

[0014] FIG. 2 is a top view showing the configuration of the gantry 2 according to the first embodiment. FIG. 2 shows the scanner 21 and two stands 22 as viewed from the positive direction of the Z axis (i.e., as viewed from above). The scanner 21 has six surfaces (top, bottom, front, back, right side, and left side). Each of the two surfaces (top and bottom) is also referred to as a "bottom surface." Each of the four surfaces (front, back, right side, and left side) is also referred to as a "side surface." The "front" is the surface facing the abdominal side of the subject. The "back" is the surface facing the dorsal side of the subject. The "right side" is the surface on the right side when viewing the abdominal side of the subject from outside the scanner 21. The "left side" is the surface on the left side when viewing the abdominal side of the subject from outside the scanner 21. Each surface of the stand 22 is defined in the same way as each surface of the scanner 21.

[0015] The scanner 21 has a camera C on the circular inner peripheral side surface that forms the opening OP. For example, the camera C is installed so as to face the center position PX of the opening OP from the front of the scanner 21. The camera C captures an optical image (i.e., an internal image) of the inside of the opening OP from a first line of sight direction D1. The camera C transmits the captured internal image to the console 3.

[0016] The camera C may be a digital camera or an infrared camera. The camera C may be installed at any position where it can photograph the inside of the opening OP. For example, the camera C is installed on the ceiling or wall of the examination room in which the pedestal 2 is installed. The camera C may be installed on a rotating frame (i.e., a rotating part), or on a main frame (i.e., a fixed part) that supports the rotating frame.

[0017] The first line of sight direction D1 is a direction starting from the installation position of the camera C and ending at the center position PX of the aperture OP. The first line of sight direction D1 is also a normal direction perpendicular to a tangent line passing through the installation position of the camera C. The center position PX is a point (e.g., the isocenter) on the central axis AX of the aperture OP.

[0018] Furthermore, the scanner 21 has two light projectors T on the inner peripheral side surface that forms the aperture OP. The two light projectors T are installed symmetrically with respect to the central axis AX (or central position PX) of the aperture OP. Only one of the two light projectors T may be installed. The two light projectors T project laser light (e.g., infrared light, visible light) for aligning the subject inserted inside the aperture OP under control of the console 3. The projected light indicates the height of the imaging section (or X-ray path). The imaging section may be an end or central imaging section among multiple imaging sections. The color of the projected light is arbitrary (e.g., red, green, blue).

[0019] The monitor M is installed, for example, in front of the scanner 21. The monitor M is installed at a position that bisects the length of the long axis direction (X-axis direction) related to the front of the scanner 21. The monitor M displays a visualized image of the internal space of the opening OP viewed from a second viewing direction D2. The second viewing direction D2 is a viewing direction that starts from the installation position PM of the monitor M and ends at the center position PX of the opening OP. In this embodiment, the second viewing direction D2 is on the same straight line as the first viewing direction D1. The monitor M is an example of a display unit.

[0020] Returning to the explanation of Fig. 1, the scanner 21 has an X-ray tube 211, a high-voltage generator 212, an X-ray detector 213, and a DAS 214. The X-ray tube 211 and the high-voltage generator 212 are installed opposite the X-ray detector 213 and the DAS 214 across an opening OP. DAS is an abbreviation for Data Acquisition System.

[0021] Specifically, the scanner 21 has a main frame (not shown) and a rotating frame 215. The main frame is made of a metal such as aluminum. The main frame supports the rotating frame 215 rotatably about a central axis AX via bearings or the like. A ring-shaped electrode (not shown) is provided at the contact portion between the main frame and the rotating frame 215, and a conductive slider (not shown) is provided so as to be in sliding contact with the ring-shaped electrode. The rotating frame 215 is made of a metal such as aluminum and has an annular shape. For example, an X-ray tube 211 and an X-ray detector 213 are attached to the rotating frame 215.

[0022] The rotating frame 215 receives power from the rotation drive device 23 and rotates around the central axis AX of the opening OP. The rotation drive device 23 generates power for rotating the rotating frame 215 in accordance with control from the console 3. The rotation drive device 23 is realized by a motor such as a direct drive motor or a servo motor, for example.

[0023] The stand 22 is a structure that supports the scanner 21 at a distance from the floor surface FL. The stand 22 is also called a "pillar." The stand 22 has, for example, a columnar shape such as a cylindrical or rectangular pillar shape. The stand 22 is attached, for example, to the side of the scanner 21. The stand 22 supports the scanner 21 so that it can slide vertically relative to the floor surface FL in a position where the central axis AX of the opening OP is maintained perpendicular to the floor surface FL in order to perform CT imaging of a subject in a standing or sitting position. The floor surface FL is an example of a surface on which the stand 22 is placed. The floor surface FL may be a surface on which the soles of the feet of a subject in a standing or sitting position are placed, or a surface on which a support device is installed.

[0024] Typically, the stand 22 is provided on both sides (right side and left side) of the scanner 21. Alternatively, one stand 22 may be provided on only one side of the scanner 21. The stand 22 may have a shape such as a U-shape, as long as it can support at least one side of the scanner 21.

[0025] The stand 22 may support the scanner 21 so that it can rotate about a horizontal axis (hereinafter referred to as the tilt axis) parallel to the floor surface FL. In this case, the scanner 21 and the stand 22 may be connected to each other via a bearing or the like. With this configuration, the gantry 2 can perform CT imaging of a subject in a standing position (standing position imaging), CT imaging of a subject in a sitting position (sitting position imaging), and CT imaging of a subject in a supine position (supine position imaging).

[0026] The stand 22 may house a stand drive device 24 for sliding the scanner 21 in the vertical direction. The stand drive device 24 generates power for sliding the scanner 21 in the vertical direction under control of the console 3. Specifically, the stand drive device 24 generates power by driving at a rotation speed according to the duty ratio, etc., of a drive signal from the console 3. The stand 22 receives power from the stand drive device 24 and slides the scanner 21 in the vertical direction relative to the stand 22. The stand drive device 24 is realized by a motor such as a servo motor, for example.

[0027] The X-ray tube 211 generates X-rays when a high voltage is applied from a high-voltage generator 212. The high-voltage generator 212 is attached to, for example, a rotating frame 215. The high-voltage generator 212 generates a high voltage to be applied to the X-ray tube 211 from power supplied from a power supply device (not shown) of the scanner 21 via a ring electrode, under the control of the console 3. The high-voltage generator 212 and the X-ray tube 211 are connected via a high-voltage cable (not shown). The high voltage generated by the high-voltage generator 212 is applied to the X-ray tube 211 via the high-voltage cable.

[0028] The X-ray detector 213 detects X-rays generated from the X-ray tube 211 and transmitted through the subject. The X-ray detector 213 has a plurality of X-ray detection elements (not shown) arranged on a two-dimensional curved surface defined by a row direction and a channel direction. The row direction is defined as the Z-axis direction. The channel direction is defined as a direction along an arc perpendicular to the row direction. Each X-ray detection element detects X-rays from the X-ray tube 211 and converts them into an electrical signal having a peak value corresponding to the intensity of the detected X-rays. Each X-ray detection element has, for example, a scintillator and a photoelectric conversion element.

[0029] The scintillator generates fluorescence upon receiving X-rays. The photoelectric conversion element converts the generated fluorescence into an electric charge pulse. The electric charge pulse has a peak value according to the intensity of the X-rays. The photoelectric conversion element may be a circuit element (e.g., a photomultiplier tube or a photodiode) that converts the fluorescence into an electric signal. The X-ray detector 213 may be an indirect conversion type detector that converts X-rays into fluorescence and then converts it into an electric signal, or a direct conversion type detector that directly converts X-rays into an electric signal.

[0030] The DAS 214 collects digital data for each view that indicates the intensity of X-rays attenuated by the subject. The DAS 214 is connected to, for example, the X-ray detector 213. The DAS 214 has an integration circuit and an A / D converter. The integration circuit integrates electrical signals from the X-ray detection elements over a predetermined view period to generate an integrated signal. The A / D converter A / D converts the integrated signal to generate digital data (projection data) having data values ​​corresponding to the peak values ​​of the integrated signal. The projection data is a set of digital values ​​of X-ray doses identified by a column number, a channel number, and a view number. The projection data is supplied to the console 3, for example, via a non-contact data transmission device (not shown) housed in the scanner 21.

[0031] The rotation drive device 23 is a device that generates power for rotating the rotating frame 215. The rotation drive device 23 generates power under control from the console 3. The rotation drive device 23 supplies the generated power to the rotating frame 215. The rotation drive device 23 may tilt the central axis AX of the opening OP around a tilt axis (particularly, the X axis) parallel to the floor surface FL.

[0032] The stand driving device 24 is a device that generates power for the stand 22. The stand driving device 24 generates power under the control of the console 3. The stand driving device 24 supplies the generated power to the stand 22. The stand driving device 24 may drive the stand 22 in the horizontal direction (X-axis direction, Y-axis direction).

[0033] (Configuration of the console) The console 3 controls the high voltage generator 212, the DAS 214, the rotation drive device 23, the stand drive device 24, etc. The console 3 has, as hardware resources, a processor such as a CPU (Central Processing Unit), and storage devices (memories) such as a ROM (Read Only Memory) and a RAM (Random Access Memory).

[0034] The console 3 has, as its components, a processing circuit 31, a memory circuit 32, an input circuit 33, a display circuit 34, and a communication circuit 35. Data communication between the components is performed via a bus (BUS). At least some of the components may be included in the pedestal 2.

[0035] The processing circuit 31 is a circuit that comprehensively controls each component of the console 3. The processing circuit 31 has at least one processor. The processor refers to circuits such as a CPU, a GPU (Graphics Processing Unit), an Application Specific Integrated Circuit (ASIC), and a Programmable Logic Device (PLD). The programmable logic device refers to circuits such as a Simple Programmable Logic Device (SPLD), a Complex Programmable Logic Device (CPLD), and a Field Programmable Gate Array (FPGA). The processing circuit 31 is an example of a processing unit.

[0036] If the processor is a CPU, the CPU reads and executes each program stored in the storage circuitry 32 to realize each function. If the processor is an ASIC, each function is incorporated as a logic circuit inside the ASIC. The processor may be configured as a single circuit or may be configured by combining multiple circuits. The processor realizes the following functions: an acquisition function 311, a generation function 312, a display control function 313, an imaging control function 314, and a system control function 315.

[0037] The acquisition function 311 is a function that performs various acquisitions. For example, the acquisition function 311 acquires an internal image of the interior OP of the opening from a camera C. The internal image is, for example, an optical image captured by the camera C. The acquisition function 311 is an example of an acquisition unit.

[0038] The generation function 312 is a function that performs various types of generation. For example, the generation function 312 generates a visualized image that visualizes the inside of the opening OP as viewed from a line of sight toward the inside of the opening OP, based on the internal image acquired by the acquisition function 311. The generation function 312 is an example of a generation unit.

[0039] The display control function 313 is a function that performs various display controls. The display control function 313 displays the visualized image generated by the generation function 312 on the monitor M (or the display circuitry 34). The display control function 313 is an example of a display control unit.

[0040] The imaging control function 314 is a function that performs various imaging controls. The imaging control function 314 controls the high voltage generator 212, DAS 214, rotation drive device 23, stand drive device 24, etc. so that the gantry 2 performs X-ray CT imaging in accordance with scan conditions. The imaging control function 314 generates CT image data based on projection data from the DAS 214, and outputs the generated CT image data to the monitor M (or display circuitry 34). The imaging control function 314 is an example of an imaging control unit.

[0041] The system control function 315 is a function that comprehensively controls each component of the console 3. The system control function 315 controls various functions of the processing circuitry 31 based on input operations received from a user via the input circuitry 33. The system control function 315 is an example of a system control unit.

[0042] Furthermore, the processing circuitry 31 realizes (1) a preprocessing function, (2) a reconstruction processing function, and (3) an image processing function. The (1) preprocessing function preprocesses the projection data output from the DAS 214. The preprocessing includes, for example, logarithmic conversion, offset correction, sensitivity correction, and beam hardening correction. The preprocessing function is an example of a preprocessing unit.

[0043] (2) The reconstruction processing function generates CT image data by performing reconstruction processing on the projection data preprocessed by the preprocessing function. The reconstruction processing is, for example, a filtered back projection method and an iterative reconstruction method. The reconstruction processing function is an example of a reconstruction processing unit.

[0044] (3) The image processing function generates predetermined image data by performing image processing (e.g., rendering processing) on ​​the CT image data generated by the reconstruction processing function. The image processing function may generate the predetermined image data based on an input operation received from a user via the input circuitry 33. The predetermined image data is, for example, tomographic image data of an arbitrary cross section and three-dimensional image data. The image processing function is an example of an image processing unit.

[0045] The memory circuitry 32 is a memory device such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or an integrated circuit memory device that stores various types of information. The memory circuitry 32 stores projection data, reconstructed image data, etc. The memory circuitry 32 may be a portable storage medium such as a CD (Compact Disc), a DVD (Digital Versatile Disc), or a flash memory. The memory circuitry 32 may be a drive device that reads and writes various types of information from and to semiconductor memory elements such as flash memory and RAM. The storage area of ​​the memory circuitry 32 may be located inside the X-ray CT apparatus 1 or inside an external storage device connected via a network. The memory circuitry 32 may store a database. The memory circuitry 32 is an example of a memory unit.

[0046] The input circuitry 33 accepts various input operations from a user, converts the accepted input operations into electrical signals, and outputs the electrical signals to the processing circuitry 31. The input circuitry 33 may be a mouse, a keyboard, a trackball, a switch, a button, a joystick, a touchpad, a touch panel display, or the like. The input circuitry 33 may accept electrical signals from an external input device provided separately from the X-ray CT apparatus 1, and output the accepted electrical signals to the processing circuitry 31. The input circuitry 33 may be provided in the gantry 2. The input circuitry 33 may be a tablet terminal capable of wirelessly communicating with the console 3. The input circuitry 33 is an example of an input unit.

[0047] The display circuitry 34 displays various types of information. The display circuitry 34 displays medical images (CT images) generated by the processing circuitry 31, a GUI (Graphical User Interface) for receiving various operations from the user, and the like. The display circuitry 34 may be a liquid crystal display (LCD), a cathode ray tube (CRT) display, an organic electroluminescence display (OLED), a plasma display, or the like. The display circuitry 34 may be provided on the gantry 2. The display circuitry 34 may be a desktop type, or may be a tablet terminal or the like capable of wireless communication with the console 3. The display circuitry 34 is an example of a display unit.

[0048] The communication circuit 35 is a circuit for communicating various types of data. The communication circuit 35 communicates CT image data based on the DICOM (Digital Imaging and Communication in Medicine) standard. The console 3 may be connected to a communication network via the communication circuit 35 and connected to an external device through the communication network. The communication circuit 35 is an example of a communication unit.

[0049] 3 is a flow diagram showing the operation of the X-ray CT apparatus 1 according to the first embodiment. The X-ray CT apparatus 1 acquires an internal image relating to the internal space of the opening OP of the scanner 21, and generates and displays a visualized image based on the acquired internal image.

[0050] (Step S1A) First, the acquisition function 311 acquires an internal image obtained by photographing the inside of the opening OP of the scanner 21 from the first line of sight direction D1. The acquisition function 311 acquires from the camera C an internal image photographed by the camera C.

[0051] (Step S2A) Next, the generation function 312 generates a visualized image based on the internal image acquired in step S1A. The visualized image is an image that visualizes the inside of the opening OP as seen from a second line of sight direction D2 that starts from the installation position PM of the monitor M and ends at the center position PX of the opening OP.

[0052] In the first embodiment, the first line of sight direction D1 and the second line of sight direction D2 coincide with each other. The generation function 312 uses the internal image as the visualized image. The generation function 312 may change the magnification ratio of the internal image and use the internal image after the change as the visualized image.

[0053] On the other hand, when the first viewing direction D1 and the second viewing direction D2 do not coincide with each other, the internal image viewed in the first viewing direction D1 from the installation position of the camera C is converted into a visualized image viewed in the second viewing direction D2 from the installation position PM of the monitor M. For example, the generation function 312 generates a visualized image by performing viewpoint conversion on the internal image based on the positional relationship between the viewing direction of the first viewing direction D1 and the viewing direction of the second viewing direction D2. A pre-trained machine learning model may be used for the viewpoint conversion. Known image processing techniques may be applied to generate the visualized image.

[0054] (Step S3A) Finally, the display control function 313 causes the monitor M to display the visualized image generated in step S2A.

[0055] Fig. 4 is an explanatory diagram showing a display example of a visualized image according to the first embodiment. Fig. 4 is a front view showing the scanner 21 and the two stands 22 as viewed from the negative direction of the Y axis (i.e., from the front).

[0056] The subject S is standing on a floor surface FL (standing position). The head and chest of the subject S are inserted, for example, into the internal space of the opening OP of the scanner 21, with the upper end of the subject S's head being lower than the upper end of the monitor M and the lower end of the subject S's chest being lower than the lower end of the monitor M. Therefore, the head of the subject S and part of the subject S's chest are included in the visualized image G on the monitor M. The visualized image G displays the head of the subject S as seen from the front. Part of the subject S's chest is blocked by the front of the scanner 21 and cannot be seen.

[0057] The visualized image G may display laser light L projected from two light projectors T onto the subject S. The monitor M can also be described as a transmission window that provides a pseudo-transmission display of the inside of the opening OP.

[0058] According to the first embodiment, the medical technician can check the state of the subject S inside the opening OP of the scanner 21 through the visualized image G displayed on the monitor M. In particular, the medical technician can visually check the height of the laser light L in the visualized image G and check the height of the imaging cross section of the subject S. Therefore, the medical technician can intuitively and easily adjust the height of the imaging cross section to a desired height of the subject S. Since the medical technician does not need to look into the laser light L from below the opening OP, the physical burden on the medical technician is reduced. As a result, the X-ray CT device 1 can reduce the physical burden associated with imaging the subject S.

[0059] As described above, the gantry 2 is installed in a CT examination room, and the console 3 is installed in a control room adjacent to the CT examination room. A medical technician may check the subject S in the CT examination room from the control room. In this case, the medical technician can grasp the state of the subject S inside the opening OP of the scanner 21 by looking down on the scanner 21 of the gantry 2.

[0060] (Second embodiment) 5 is a top view showing the configuration of the stand according to the second embodiment. In the second embodiment, one stand 22 holds the left side surface of the scanner 21 (cantilever structure).

[0061] The scanner 21 may have multiple cameras on the circular inner peripheral side surface that forms the opening OP. The multiple cameras are, for example, a camera C1 and a camera C2. The camera C1 captures an image of the internal space of the opening OP from, for example, a first line-of-sight direction D1A, and obtains a first optical image (an example of a first internal image). The camera C1 transmits the first internal image to the console 3.

[0062] The camera C2 captures an image of the interior space of the opening OP from, for example, a first line-of-sight direction D1B to obtain a second optical image (an example of a second internal image). The first line-of-sight direction D1B is, for example, perpendicular to the first line-of-sight direction D1A. The camera C2 transmits the second internal image to the console 3. That is, the two cameras C1 and C2 are installed in different positions and have similar functions. The first internal image and the second internal image are optical images of the interior of the opening OP viewed from different viewpoints.

[0063] The monitor M1 is provided in front of the scanner 21. The monitor M1 displays a first visualized image of the inside of the opening OP viewed from a second viewing direction D2A. The second viewing direction D2A is a viewing direction that starts at the installation position PM1 of the monitor M1 and ends at the center position PX of the opening OP. The second viewing direction D2A is on the same straight line as the first viewing direction D1A.

[0064] The monitor M2 is provided on the right side of the scanner 21. The monitor M2 is installed, for example, at a position that bisects the length of the long axis direction (Y-axis direction) of the side of the scanner 21. The monitor M2 displays a second visualized image of the inside of the opening OP viewed from a second viewing direction D2B. The second viewing direction D2B is a viewing direction that starts from the installation position PM2 of the monitor M2 and ends at the center position PX of the opening OP. The second viewing direction D2B is on the same straight line as the first viewing direction D1B. In other words, the two monitors M1 and M2 are installed in different positions and have similar functions.

[0065] The two monitors M1 and M2 may be installed according to the orientation of the subject. For example, monitor M1 may be installed to face the front of the subject, and monitor M2 may be installed to face the side of the subject. This allows the technician to observe the front of the subject inside the opening OP by looking at monitor M1, and the side of the subject by looking at monitor M2. In other words, the technician can check whether the imaging cross-sections are properly aligned in the left-right and front-back directions of the subject.

[0066] 6A and 6B are explanatory diagrams showing an example of a display of a visualized image according to the second embodiment. Fig. 6A shows the scanner 21 and stand 22 as viewed from the negative direction of the Y axis (i.e., as viewed from the front). Fig. 6B shows the scanner 21 and stand 22 as viewed from the positive direction of the X axis (i.e., as viewed from the right side).

[0067] As shown in Fig. 6(A), the subject S stands on a floor FL. The head of the subject S is displayed as a visualized image G on a monitor M1. The subject S and the visualized image G are the same as those in Fig. 4. The scanner 21 has a monitor M2 on the right side.

[0068] As shown in FIG. 6(B), the monitor M2 is installed on the right side of the scanner 21. The monitor M2 is installed so as to face the right side of the subject S. The head of the subject S is displayed as a visualized image G on the monitor M2. The visualized image G displays the head of the subject S as viewed from the right side. A part of the chest of the subject S is blocked by the right side of the scanner 21 and cannot be seen. The visualized image G displays the laser light L projected onto the subject S.

[0069] The monitors M1 and M2 display visualized images G obtained by virtually transmitting through the interior of the scanner 21 from their respective installation positions (or viewpoints). Through the visualized image G on the monitor M1, the laboratory technician can observe the head of the subject S viewed from the front and the laser light L. Through the visualized image G on the monitor M2, the laboratory technician can observe the head of the subject S viewed from the right side and the laser light L.

[0070] The monitors M1 and M2 are installed on the scanner 21. When the scanner 21 moves in any of the axial directions (X-axis, Y-axis, Z-axis), the monitors M1 and M2 also move in the same direction. In other words, there is no need to move the monitors M1 and M2 independently of the scanner 21. The monitors M1 and M2 display a visualized image G that is pseudo-transmitted through the inside of the scanner 21 from the position after movement. By moving the scanner 21, the technician can observe the subject S and the laser light L as seen from any position after movement.

[0071] In the second embodiment, the camera C1 and the camera C2 may be provided so as to be movable in the circumferential direction of the opening OP. For example, the camera C1 may move so as to always capture the front of the subject S, and the camera C2 may move so as to always capture the side of the subject S. Even if the subject S changes position within the opening OP, the technician can check the condition of the subject S from a specific direction, such as the front or side of the subject S.

[0072] The type of camera C1 and the type of camera C2 may be different. For example, the camera C1 and the camera C2 may be selected in any combination from the group consisting of a visible light camera, a near-infrared camera, a stereo camera, a depth camera, etc. The camera C1 and the camera C2 may be installed adjacent to each other to function as a single stereo camera.

[0073] The angle of view of camera C1 and the angle of view of camera C2 may be different. For example, camera C2 may have a wider angle of view than camera C1. In this case, camera C1 may photograph the head of subject S from the front, and camera C2 may photograph the head and chest (or whole body) of subject S. The technician can check the face of subject S on monitor M1, and can check a wider area on monitor M2 than camera C1.

[0074] (Third embodiment) Fig. 7 is a top view showing the configuration of the stand 2 according to the third embodiment. As shown in Fig. 7, the monitor M may be installed on the back of the scanner 21. In this case, the first line of sight D1 of the camera C and the second line of sight D2 of the monitor M may be on the same straight line. The monitor M displays a visualized image of the inside of the opening OP viewed from the second line of sight D2. The visualized image shows the internal space of the opening OP by being pseudo-transparent to the scanner 21.

[0075] (Fourth embodiment) FIG. 8 is a top view showing the configuration of the stand 2 according to the fourth embodiment. As shown in FIG. 8, the monitor M may be installed on the left side of the stand 22. That is, the monitor M may be installed on the surface of the stand 22 opposite the contact surface between the scanner 21 and the stand 22. In this case, the first line of sight D1 of the camera C1 and the second line of sight D2 of the monitor M may be on the same straight line. The monitor M displays a visualized image of the inside of the opening OP as seen from the second line of sight D2. The visualized image shows the interior space of the opening OP in a pseudo-transparent manner through the scanner 21 and the stand 22.

[0076] (Fifth embodiment) Fig. 9 is a top view showing the configuration of the stand 2 according to the fifth embodiment. Fig. 9(A) shows the scanner 21 and two stands 22 according to a first configuration example. Fig. 9(B) shows the scanner 21 and two stands 22 according to a second configuration example.

[0077] As shown in Fig. 9(A), the scanner 21 has a camera C1 on the inner peripheral side surface of the circular opening OP. The camera C1 photographs the inside of the opening OP from a first line of sight direction D1A. The camera C1 is similar to the camera C (see Fig. 2(A)).

[0078] The scanner 21 has a camera C2 on its rear surface. The camera C2 is installed at a position that bisects the length of the scanner 21 in the long axis direction (X-axis direction) on its rear surface. The camera C2 captures an optical image (rear-side image) by photographing the rear surface of the scanner 21 from a first line-of-sight direction D1B. That is, the camera C2 captures an optical image (first opposite-side image) of the external space from the side (rear surface) facing the installation position PM of the monitor M. The camera C2 transmits the first opposite-side image to the console 3. The first line-of-sight direction D1B is on the same straight line as the first line-of-sight direction D1A and the second line-of-sight direction D2.

[0079] 9(B), there is a case where the second line of sight D2 of the monitor M intersects with the first line of sight D1A of the camera C1 at an angle θ. In this case, the first line of sight D1B is on the same straight line as the first line of sight D1A, but is not on the same straight line as the second line of sight D2.

[0080] 10 is a flow diagram showing the operation of the X-ray CT apparatus 1 according to the fifth embodiment. The X-ray CT apparatus 1 acquires a first opposite-side image obtained by capturing an image of the side opposite to the installation position PM of the monitor M, and generates and displays a second opposite-side image based on the acquired first opposite-side image. The X-ray CT apparatus 1 according to the fifth embodiment may perform the same operation as in the first embodiment (see FIG. 3).

[0081] (Step S1B) First, the X-ray CT apparatus 1 acquires a first opposite-side image. Specifically, the acquisition function 311 acquires a first opposite-side image captured on the side opposite to the installation position PM of the monitor M. The acquisition function 311 acquires the first opposite-side image captured by the camera C2 from the camera C2.

[0082] (Step S2B) Next, the X-ray CT apparatus 1 generates a second opposite-side image. Specifically, the generation function 312 generates the second opposite-side image based on the first opposite-side image acquired in step S1B. The second opposite-side image is the first opposite-side image viewed (after viewpoint conversion) from the second line of sight direction D2.

[0083] That is, the generation function 312 converts a first opposite side image viewed in a first line of sight direction D1B from the installation position of the camera C2 into a second opposite side image viewed in a second line of sight direction D2 from the installation position PM of the monitor M. A technique similar to that of step S2A (see FIG. 3) may be applied to this conversion. In the example of FIG. 9(A), the second opposite side image is the same as the first opposite side image captured by the camera C2. In the example of FIG. 9(B), the second opposite side image is an optical image obtained by rotating the viewpoint of the first opposite side image captured by the camera C2 by an angle θ.

[0084] (Step S3B) Finally, the X-ray CT apparatus 1 displays the second opposite-side image. Specifically, the display control function 313 displays the second opposite-side image generated in step S2B on the monitor M. The display control function 313 may display the second opposite-side image together with the visualized image G on the monitor M. The display control function 313 may switch between displaying the visualized image G and the second opposite-side image in accordance with an instruction input by the medical technician via the input circuitry 33.

[0085] According to the fifth embodiment, the medical technician can check the space on the opposite side of the scanner 21 and the stand 22 as seen from the second line of sight D2 of the monitor M through the second opposite side image displayed on the monitor M. That is, the medical technician can check the space that is blocked by the scanner 21 and the stand 22 and cannot be seen with the naked eye. The medical technician can recognize the presence of an object (e.g., an IV pole, a carrier) placed on the opposite side of the scanner 21 and the stand 22 without moving himself / herself. As a result, the X-ray CT device 1 can eliminate the burden on the medical technician of moving to the opposite side of the scanner 21 and the stand 22.

[0086] (Sixth embodiment) Fig. 11 is a top view showing the configuration of the stand 2 according to the sixth embodiment. Fig. 11(A) is a top view showing the scanner 21 and two stands 22 according to a first configuration example. Fig. 11(B) is a top view showing the scanner 21 and two stands 22 according to a second configuration example. For convenience of explanation, the camera C that captures internal images is not shown.

[0087] As shown in FIGS. 11(A) and 11(B), the scanner 21 has a rail R on its front surface. The rail R extends circumferentially around the opening OP on the front surface of the scanner 21. A moving mechanism (not shown), such as a caster, engages with the rail R. The moving mechanism moves (or slides) the monitor M along the rail R. The rail R may be installed on the rear surface of the scanner 21 or on the stand 22. The rail R may be installed in any direction and along any path. The rail R may be installed on the surface of at least one of the scanner 21 and the stand 22.

[0088] The monitor M moves in the left direction DR1 or the right direction DR2 when viewed from a user U (e.g., a medical technician) who is in front of the scanner 21. When the user U moves, the monitor M may automatically move to follow this movement. At this time, the monitor M moves so that the user U is positioned on a line indicating the second line of sight D2. The monitor M may be moved manually by the medical technician, or may be moved automatically in accordance with control by the X-ray CT apparatus 1 (particularly the imaging control function 314).

[0089] In FIG. 11(A), the user U is positioned directly in front of the monitor M. The second line of sight direction D2E of the monitor M coincides with a line passing through the position PU of the user U and the center position PX of the opening OP. In FIG. 11(B), the user U moves to the right by an angle θ around the center position PX of the opening OP, using the second line of sight direction D2E as a reference. At this time, the monitor M moves in the right direction DR2 so that the line of sight direction D2F of the monitor M coincides with a line passing through the position PU of the user U and the center position PX of the opening OP.

[0090] 12 is a flow diagram showing the operation of the X-ray CT apparatus 1 according to the sixth embodiment. The X-ray CT apparatus 1 acquires an internal image related to the opening OP of the scanner 21, and acquires position information of the user U. The X-ray CT apparatus 1 automatically moves the monitor M based on the acquired position information, and generates and displays a visualized image G based on the installation position PM of the monitor M after the movement.

[0091] (Step S1C) First, the X-ray CT apparatus 1 acquires an internal image. Step S1C is similar to step S1A.

[0092] (Step S2C) Next, the X-ray CT apparatus 1 acquires position information of the user U. Specifically, the acquisition function 311 acquires position information related to the position PU of the user U. The user U may carry a position sensor (e.g., a magnetic sensor, an ultrasonic sensor, or an optical sensor). The position sensor transmits the position information of the user U to the console 3.

[0093] (Step S3C) Subsequently, the X-ray CT apparatus 1 moves the monitor M. Specifically, the imaging control function 314 moves the monitor M by driving the movement mechanism of the monitor M based on the position information acquired in step S2C.

[0094] (Step S4C) Subsequently, the X-ray CT apparatus 1 generates a visualized image G. Specifically, the generation function 312 generates the visualized image G based on the installation position PM of the monitor M moved in step S3C. Step S4C is similar to step S2A.

[0095] (Step S5C) Finally, the X-ray CT apparatus 1 displays the visualized image G. Step S5C is similar to step S3A.

[0096] Fig. 13 is an explanatory diagram showing a display example of a visualized image G according to the sixth embodiment. Fig. 13(A) and Fig. 13(B) are front views showing the scanner 21 and two stands 22. The state in Fig. 13(A) corresponds to the state in Fig. 11(A). The state in Fig. 13(B) corresponds to the state in Fig. 11(B).

[0097] In Fig. 13(A), a rail R extends along a straight line that bisects the height of the front of the scanner 21 (height in the Z-axis direction). A monitor M displays a visualized image G of the head of the subject S viewed from the front direction. In Fig. 13(B), the monitor M displays a visualized image G of the head of the subject S viewed from a line of sight that forms an angle θ with respect to the front direction.

[0098] According to the sixth embodiment, the laboratory technician can check the state of the subject S inside the opening OP from his / her own position through the monitor M, as if looking through the interior of the opening OP. The monitor M automatically moves on the rail R according to the position of the laboratory technician. Therefore, the laboratory technician can check the subject S from any line of sight direction, and can intuitively and easily grasp the spatial position of the laser light L projected onto the subject S.

[0099] (Variation 1) In the above-described embodiment, an example has been described in which the visualized image G displays the actual laser light L projected onto the subject S. However, the visualized image G on the monitor M may display a virtual laser light that is to be projected onto the subject S. The visualized image G does not need to display the virtual laser light while the actual laser light L is being projected onto the subject S. For example, by displaying the virtual laser light, the display control function 313 can assist the technician in determining the height of the cross section to be photographed when the actual laser light L is not being projected. The display control function 313 may control the display so that the virtual laser light does not overlap the actual laser light L displayed in the visualized image G. This control allows the technician to easily view the actual laser light L. Furthermore, by not projecting the laser light L onto the subject S, it is possible to prevent the subject S from feeling dazzled.

[0100] (Variation 2) The visualized image G may display an area finder instead of the linear laser light L. The area finder is a rectangular frame indicating the range (scan area) that the scanner 21 can capture. The area finder is projected onto the subject S from a projector, similar to the laser light L. As in variation 1, the visualized image G may display a virtual area finder. The visualized image G does not need to display a virtual area finder while the actual area finder is projected onto the subject S. The area finder may be a rectangular frame indicating the range from the start position to the end position of X-ray CT imaging by the scanner 21 (the range of the volume scan).

[0101] (Variation 3) The visualized image G may display the subject S schematically as a schema (picture) instead of the actual subject S. The visualized image G may display a schema corresponding to a whole-body image of the subject S. The visualized image G may display a virtual laser light or a virtual area finder superimposed on the schema corresponding to the whole-body image. By displaying a schema, the X-ray CT device 1 can protect the privacy of the subject S.

[0102] (Variation 4) The visualized image G may be displayed on a monitor other than the monitor M. The monitor M or another monitor may be an operation panel of the scanner 21, a monitor suspended from the ceiling (a ceiling-mounted monitor), or a monitor of the console 3 (i.e., the display circuit 34). The monitor M or another monitor may be a portable terminal (e.g., a tablet terminal) carried by the user U. The technician can use his or her own portable terminal to closely observe the visualized image G close to him or her.

[0103] (Variation 5) The visualized image G may be projected by a projector onto a surface where the installation position PM of the monitor M is located. For example, if the monitor M is installed in front of the scanner 21, the projector projects the visualized image G onto all or part of the front surface of the scanner 21. The projector may project the visualized image G onto the ceiling or wall surface of the CT examination room. The visualized image G may be projected using projection mapping technology. The technician can check the projected visualized image G and observe the visualized image G in a wider range than the display screen of the monitor M.

[0104] (Variation 6) The monitor M may be a liquid crystal display or an organic electroluminescence (EL) display. The monitor M may be installed according to the orientation of the subject. For example, the monitor M may be installed so as to face the front of the subject. The imaging control function 314 may switch the power of the monitor M on or off according to at least one of (1) an instruction from a medical technician, (2) the attitude of the scanner 21, and (3) the imaging mode of the scanner 21. Regarding (1), the medical technician may input the instruction through the input circuitry 33. Regarding (2), the attitude of the scanner 21 may be a tilt angle around the X-axis or Y-axis. Regarding (3), each imaging mode includes a set of multiple imaging parameters different from each other. The imaging parameters include a tube current, a tube voltage, an X-ray tube rotation speed, an acquisition slice thickness, an image reconstruction method, a field of view (FOV), a reconstruction slice thickness, a helical pitch, an interpolation reconstruction method, etc.

[0105] (Variation 7) The user may move the virtual laser light (or virtual scan area) to a desired position in the visualized image G displayed on the monitor M. The imaging control function 314 may display the moved virtual laser light in a predetermined display mode, or may move the scanner 21 to match the position of the laser light. Variation 7 includes the following steps S1D ​​to S5D.

[0106] First, the user selects a virtual laser beam in the visualized image G (step S1D). The user selects the virtual laser beam by touching with a finger, clicking with a mouse, or the like. Next, the user moves the selected virtual laser beam to a desired position in the visualized image G (step S2D). The user moves the selected virtual laser beam by dragging or long pressing with a finger or a mouse.

[0107] Next, the photography control function 314 displays the virtual laser light after the movement on the visualized image G (step S3D). The photography control function 314 may display the virtual laser light after the movement in a display mode different from the virtual laser light before the movement. The photography control function 314 may vary the display mode (e.g., color, thickness, type (solid line, dashed line), display time (constant display, blinking display)) of the line indicating the virtual laser light.

[0108] Next, the user confirms the position of the virtual laser light after the movement (step S4D). The user confirms the position of the virtual laser light by pressing a confirmation button, using voice recognition, etc. The shooting control function 314 accepts the user's operation to confirm the position of the virtual laser light.

[0109] Finally, the imaging control function 314 moves the scanner 21 to match the position of the virtual laser light after the movement (step S5D). The imaging control function 314 may move the scanner 21 in the vertical direction (Z-axis direction) to match the position. If the X-ray CT apparatus 1 is equipped with a mechanism (e.g., rails) that can move the stand 22 in the horizontal direction (X-axis direction, Y-axis direction), the imaging control function 314 may move the scanner 21 together with the stand 22 in the horizontal direction via the mechanism.

[0110] According to at least one of the embodiments described above, it is possible to reduce the physical burden on the subject involved in imaging. Similar effects can be obtained by any combination of each embodiment and each modification.

[0111] 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]

[0112] 1 X-ray CT device 2 Mounting stand 3 Console 21 Scanner 22 Stand 23 Rotational drive unit 24 Stand drive unit 31 Processing circuit 32 Memory circuit 33 Input circuit 34 Display circuit 35 Communication Circuit 211 X-ray tube 212 High Voltage Generator 213 X-ray detector 214 DAS 215 Rotating Frame 311 Acquisition Function 312 Generation function 313 Display Control Function 314 Shooting control function 315 System Control Functions C, C1, C2 cameras D1,D1A,D1B 1st line of sight direction D2,D2A,D2B,D2E,D2F 2nd line of sight direction DR1 Left direction DR2 Right direction G Visualized image L laser light M, M1, M2 monitor OP Opening PM, PM1, PM2 installation position PU position PX center position R rail S subject T Floodlight θ angle

Claims

1. a scanner having an opening through which a subject is inserted; a stand that supports the scanner so that the scanner can move in a vertical direction; an acquisition unit that acquires an internal image of the inside of the opening from a camera; a generation unit that generates a visualized image that visualizes the inside of the opening as viewed from a line of sight toward the inside of the opening, based on the internal image; a display control unit that displays the visualized image on a display unit; An X-ray CT device comprising:

2. the visualized image is actually projected from a projector onto the subject, and displays actual laser light indicating the height of the imaging cross section in the subject. The X-ray CT apparatus according to claim 1.

3. the visualized image is to be projected onto the subject, and displays a virtual laser light indicating the height of the imaging cross section in the subject; The X-ray CT apparatus according to claim 1.

4. the visualized image does not display the virtual laser light while the laser light is actually projected from a projector onto the subject; The X-ray CT apparatus according to claim 3.

5. an imaging control unit that moves a position of the virtual laser light in the visualized image in response to an operation from a user, and moves the scanner in accordance with the position of the virtual laser light after the movement; The X-ray CT apparatus according to claim 3.

6. the display unit is provided on a surface of at least one of the scanner and the stand, the acquisition unit acquires, from another camera, an opposite-side image of a space opposite to the surface on which the display unit is provided, The display control unit causes the opposite-side image to be displayed on the display unit. The X-ray CT apparatus according to claim 1.

7. a rail installed on a surface of at least one of the scanner and the stand; a moving mechanism that moves the display unit along the rail, The X-ray CT apparatus according to claim 1.

8. the line of sight direction is a direction from a position where the display unit is provided toward a center position of the opening, the movement mechanism moves the display unit so that the user is positioned on a straight line indicating the line of sight. The X-ray CT apparatus according to claim 7.

9. the visualized image is a schematic representation of the subject as a schema; The X-ray CT apparatus according to claim 1.

10. The display unit is a portable terminal carried by a user. The X-ray CT apparatus according to claim 1.

11. the display unit is provided on a surface of at least one of the scanner and the stand, The display device further includes a projector that projects the visualized image onto the surface on which the display unit is provided. The X-ray CT apparatus according to claim 1.

12. the display unit is a display, and an imaging control unit that switches the power of the display on or off in accordance with at least one of the attitude of the scanner and the imaging mode of the scanner. The X-ray CT apparatus according to claim 1.

13. the display unit is provided on a surface of the stand opposite to a surface where the scanner and the stand face each other, the generation unit generates a visualized image viewed from a line of sight direction from a position where the display unit is provided toward a center position of the opening. The X-ray CT apparatus according to claim 1.

14. a scanner having an opening through which a subject is inserted; a stand that supports the scanner so that the scanner can move in a vertical direction; A display method for an X-ray CT apparatus comprising: The computer An internal image of the inside of the opening is acquired from a camera; generating a visualized image based on the internal image, the visualized image being obtained by visualizing the interior of the opening as viewed from a line of sight toward the interior of the opening; displaying the visualized image on a display unit; Display method.

15. a scanner having an opening through which a subject is inserted; a stand that supports the scanner so that the scanner can move in a vertical direction; A display program for an X-ray CT apparatus comprising: On the computer, an acquisition function for acquiring an internal image of the inside of the opening from a camera; a generation function of generating a visualized image that visualizes the inside of the opening as viewed from a line of sight toward the inside of the opening, based on the internal image; a display control function for displaying the visualized image on a display unit; A display program that realizes this.

Images