Radiological imaging system

Abstract

To provide a radiographic imaging system capable of supporting work performed when taking a radiation image.SOLUTION: A radiographic imaging system has a radiation generator having a source section for emitting radiation, a projector for projecting an image toward an emission direction of radiation, and at least one processor. The processor acquires distance information for showing a distance to a projection surface where an image is projected from the source section, acquires a subject image which is a radiation image taken in the past relative to a subject of the radiation image, derives, based on the distance information, a visualization range of the subject visualized on the radiation image based on the radiation emitted from the source section, which is taken relative to the subject, trims the subject image based on the visualization range, and causes the projector to project the trimmed subject image.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The disclosed technology relates to a radiation imaging system.

Background Art

[0002] As technologies related to a system including a radiation generating device and a radiation detecting device, the following are known. For example, Patent Document 1 describes a processing device used in a fluoroscopic imaging apparatus including a radiation source that continuously irradiates a subject with radiation and a radiation detector that detects the radiation transmitted through the subject and outputs a radiation image. The processor of the processing device acquires the thickness of the subject measured by a body thickness measurement sensor, sets a tone conversion function used for tone conversion processing on the radiation image according to the thickness, acquires the radiation image output by the radiation detector, and starts tone conversion processing using the set tone conversion function.

[0003] Patent Document 2 describes a radiation intensity estimation device used in a mobile radiation generating device that has a radiation generating unit including a radiation tube that emits radiation and is movable by a carriage unit having wheels, and estimates the intensity of radiation prior to radiation imaging. The processor of the radiation intensity estimation device executes an optical image acquisition process for acquiring an optical image of an imaging target of radiation imaging and an optical image of the surroundings of the imaging target from a camera, a distance information acquisition process for acquiring distance information indicating the distance from the radiation tube to an object from a distance sensor, a specifying process for specifying the type of object in the optical image, and an estimation process for estimating the intensity of radiation in the environment shown in the optical image based on reference information including the distance information and the specifying result of the type of object.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

[0005] Long-length imaging is a well-known technique for capturing radiographic images. Long-length imaging is a method for capturing areas that cannot be covered by standard-sized radiation detectors. In long-length imaging, for example, multiple radiographic images are captured by moving the radiation detector in the long-length direction while changing the emission direction and emitting radiation multiple times.

[0006] In long-length radiography, the radiation source is positioned with the patient in a specific location so that the desired area of ​​the subject is included in a series of radiographic images. For example, if the distance between the radiation source and the subject is too close, the desired area may not be captured even with long-length radiography. Positioning the radiation source in long-length radiography takes more time than in general radiography. Depending on the patient's illness or injury, it may be difficult for the patient to maintain a specific posture (e.g., standing) for an extended period of time in accordance with the radiography procedure.

[0007] The disclosed technology was developed in light of the above points and is intended to support the work performed when taking radiographic images. [Means for solving the problem]

[0008] A radiation imaging system according to the disclosed technical embodiment includes a radiation generator having a radiation source that emits radiation, a projector that projects an image in the direction of radiation emission, and at least one processor. The processor acquires distance information indicating the distance from the radiation source to the projection surface on which the image is projected, acquires a subject image which is a radiation image previously taken of the subject of the radiation image, derives the range of the subject to be depicted in the radiation image based on radiation emitted from the radiation source that is taken of the subject, trims the subject image based on the range of depiction, and projects the trimmed subject image onto the projector.

[0009] The radiation imaging system may further include a measuring unit for measuring the distance from the radiation source to the projection surface. The processor may acquire posture information indicating the subject's posture when taking a radiation image of the subject, and select a subject image based on the posture information. The processor may acquire subject information including body size information indicating the subject's physique, and set the projection size of the subject image based on the body size information.

[0010] The processor may acquire determined distance information indicating the distance determined as the distance to the projection plane, acquire range specification information specifying the range of the subject to be depicted in the radiation image taken of the subject, and derive radiation emission conditions based on the determined distance information and range specification information. The emission conditions may include the number of radiation emission cycles from the radiation source. The processor may control the emission timing for each radiation emission from the radiation source based on the determined distance information and range specification information. [Effects of the Invention]

[0011] The disclosed technology makes it possible to support the work performed when taking radiographic images. [Brief explanation of the drawing]

[0012] [Figure 1] This figure shows an example of the configuration of a radiographic imaging system according to an embodiment of the disclosed technology. [Figure 2] This figure shows an example of the operation of a radiation generator and a radiation detector during long-length imaging according to an embodiment of the disclosed technology. [Figure 3] This figure shows an example of the hardware configuration of the control system for a radiation generator according to an embodiment of the disclosed technology. [Figure 4] This is a functional block diagram showing an example of the functional configuration of a radiation generator according to an embodiment of the disclosed technology. [Figure 5] This figure shows the relationship between the distance from the radiation source to the projection plane and the range of the subject depicted in the radiation image according to an embodiment of the disclosed technology. [Figure 6]It is a diagram showing an example of a subject image projected onto a projection plane according to an embodiment of the disclosed technology. [Figure 7] It is a flowchart showing an example of the flow of imaging support processing according to an embodiment of the disclosed technology. [Figure 8] It is a functional block diagram showing an example of the functional configuration of a radiation generating device according to an embodiment of the disclosed technology. [Figure 9] It is a flowchart showing an example of the flow of imaging support processing according to an embodiment of the disclosed technology.

Embodiments for Carrying Out the Invention

[0013] Hereinafter, an example of an embodiment of the disclosed technology will be described while referring to the drawings. In each of the drawings, the same or equivalent constituent elements and parts are given the same reference numerals, and redundant explanations are omitted.

[0014] [First Embodiment] FIG. 1 is a diagram showing an example of the configuration of a radiation imaging system 100 according to an embodiment of the disclosed technology. The radiation imaging system 100 includes a radiation generating device 10, a radiation detecting device 20, a console 30, and a partition 40.

[0015] The radiation generating device 10 emits radiation for taking a radiation image. The radiation is, for example, X-rays. The radiation generating device 10 has a so-called ceiling traveling type form, and includes a guide rail 11 attached to the ceiling, a traveling unit 12 that travels on the guide rail 11, a telescopic support unit 13 connected to the traveling unit 12, and a radiation source unit 14 attached to the tip of the support unit 13. The detailed configuration of the radiation generating device 10 will be described later.

[0016] The radiation detection device 20 detects radiation emitted from the radiation generator 10 and generates a radiation image. The radiation detection device 20 has a detection panel 21 called an FPD (Flat Panel Detector), in which multiple pixels that accumulate charge corresponding to the radiation are arranged in a two-dimensional matrix. When the radiation detection device 20 detects the start of radiation irradiation, it starts an accumulation operation to accumulate charge in the pixels, and when it detects the end of radiation irradiation, it starts a readout operation to read out the charge accumulated in the pixels as an electrical signal. The radiation detection device 20 generates a radiation image based on the charge read out from the pixels. The radiation detection device 20 has a support column 22 that supports the detection panel 21 so that it can be raised and lowered.

[0017] The console 30 is, for example, a desktop computer. The console 30 may also be a notebook computer or a tablet computer. The console 30 has a display 31 for displaying various screens, input devices 32 such as a keyboard and mouse, and a storage medium (not shown) such as a hard disk. The console 30 is communicated with each of the radiation generator 10 and the radiation detection device 20. The communication between these devices may be wired or wireless.

[0018] On the display 31 of the console 30, a plurality of types of shooting menus are displayed in a selectable form. The user operates the input device 32 of the console 30 to select one shooting menu that matches the shooting technique specified in the shooting order from among the plurality of types of shooting menus. The shooting menu information indicating the selected shooting menu is transmitted to the radiation generating device 10. The shooting menu information includes information indicating the shooting part, shooting posture, and shooting direction of the subject 50. The shooting part is, for example, the chest, head, neck, abdomen, waist, shoulder, elbow, hand, knee, ankle, etc. The shooting posture is, for example, the standing position, lying position, sitting position, etc. The shooting direction is, for example, the front, back, side, etc. In a storage medium (not shown) of the console 30, subject information is stored. The subject information includes physique information indicating the physique of the subject 50. The physique information includes at least one of the height, chest circumference, abdominal circumference, and dimensions of other parts of the subject 50. The subject information may be acquired from an external system such as RIS (Radiology Information Systems), for example, or may be acquired by manual input by the user. Also, in the storage medium of the console 30, radiation images taken of the subject 50 in the past are stored.

[0019] The partition 40 is a plate-like member disposed between the radiation detection device 20 and the subject 50 in order to ensure the safety of the subject 50 during the shooting of the radiation image. The partition 40 is made of a material (for example, plastic) that is permeable to the radiation emitted from the radiation generating device 10. The surface of the partition 40 on the side of the subject 50 constitutes a projection surface 41 on which a subject image to be described later is projected.

[0020] In the radiation image shooting system 100, by the cooperation of the radiation generating device 10 and the radiation detection device 20, long-size shooting can be performed. In long-size shooting, while moving the radiation detection device 20 in the long-size direction (the direction along the column part 22), radiation is emitted from the radiation generating device 10 a plurality of times while changing the emission direction, whereby a plurality of radiation images are taken.

[0021] Figure 2 shows an example of the operation of the radiation generator 10 and the radiation detection device 20 during long-length imaging. During long-length imaging, the detection panel 21 moves along the support column 22, for example, from vertically upward to downward. The radiation source 14 of the radiation generator 10 rotates in conjunction with the movement of the detection panel 21 so that the direction of radiation emission, indicated by the dashed arrow in Figure 2, faces the detection panel 21. While the radiation source 14 is rotating, radiation is emitted multiple times at predetermined timings, generating multiple radiation images. The multiple radiation images are combined to create a single long-length image. The movement range of the detection panel 21, the rotation angle range of the radiation source 14, the number of radiation emission times, and the radiation emission timing are set so that the desired range of the subject is covered in the multiple radiation images obtained by long-length imaging.

[0022] Figure 3 shows an example of the hardware configuration of the control system for the radiation generator 10. The radiation generator 10 includes a radiation source unit 14, a projector 61, a measurement unit 62, a drive mechanism 15, a communication interface 16, a processor 17, RAM (Random Access Memory) 18, and non-volatile memory 19.

[0023] The radiation source unit 14 has a radiation tube and a field limiter (neither shown). The radiation tube is equipped with a filament, a target, a grid electrode, etc. (neither shown). A voltage is applied between the filament, which is the cathode, and the target, which is the anode. The voltage applied between the filament and the target is called the tube voltage. The filament emits thermionic electrons toward the target in accordance with the applied tube voltage. The target emits radiation through collisions with thermionic electrons from the filament. The grid electrode is positioned between the filament and the target. The grid electrode changes the flow rate of thermionic electrons from the filament toward the target in accordance with the applied voltage. This flow rate of thermionic electrons from the filament toward the target is called the tube current.

[0024] A field limiter, also called a collimator, limits the field of radiation emitted from a radiation tube. For example, a field limiter might consist of four shielding plates, such as lead, arranged on each side of a rectangle, with a rectangular emission aperture in the center that allows radiation to pass through. The field limiter changes the size of the emission aperture by altering the position of each shielding plate, thereby changing the radiation field.

[0025] The projector 61 is an image projection device that projects a subject image onto the projection surface 41 of the screen 40 prior to the acquisition of a radiation image. The subject image is a radiation image of the subject 50, which is the subject of the radiation image acquisition, that was previously acquired using a long-length imaging technique. The projector 61 is installed on the radiation emission side of the radiation source unit 14. That is, the image projection direction of the projector 61 is the same as the radiation emission direction.

[0026] Prior to capturing a radiation image, the measurement unit 62 measures the distance from the radiation source unit 14 to the surface of the screen 40, i.e., the projection surface 41. The distance from the radiation source unit 14 to the projection surface 41 changes as the traveling unit 12 moves along the guide rail 11. The measurement unit 62 may be configured as a ranging device that measures the distance to the object surface using, for example, a TOF (Time of Flight) method or a LiDAR (light detection and ranging) method. The measurement unit 62 generates distance information indicating the measured distance. The measurement unit 62 is located on the radiation emission side of the radiation source unit 14.

[0027] The drive mechanism 15 includes an electric motor or other device for performing the travel motion of the travel section 12, the extension and retraction motion of the support column section 13, and the rotation motion of the radiation source section 14. The communication interface 16 is an interface for communicating with the console 30. The radiation generator 10 acquires subject information, including body size information, shooting menu information, and subject images from the console 30 via the communication interface 16.

[0028] The non-volatile memory 19 is a non-volatile storage medium such as flash memory. The imaging support program 200 is stored in the non-volatile memory 19. The RAM 18 is work memory for the processor 17 to execute processing. The processor 17 loads the imaging support program 200 stored in the non-volatile memory 19 into the RAM 18 and executes processing according to the imaging support program 200.

[0029] Figure 4 is a functional block diagram showing an example of the functional configuration of the radiation generator 10 when the processor 17 performs imaging support processing (see Figure 7) according to the imaging support program 200. By executing the imaging support program 200, the processor 17 functions as an information acquisition unit 71, a position control unit 72, a subject image acquisition unit 73, a subject image selection unit 74, a subject image processing unit 75, and a subject image projection unit 76.

[0030] The information acquisition unit 71 acquires shooting menu information and subject information transmitted from the console 30. As described above, the shooting menu information includes information indicating the shooting area, shooting posture, and shooting direction of the subject 50. The subject information includes body size information indicating the body size of the subject 50.

[0031] The position control unit 72 performs a provisional positioning of the radiation source unit 14 based on the information indicating the shooting area, shooting posture, and shooting direction included in the shooting menu information acquired by the information acquisition unit 71. That is, the position control unit 72 controls the travel unit 12 and support unit 13 of the radiation generator 10 to move the radiation source unit 14 to a position determined according to the shooting area, shooting posture, and shooting direction. This provisionally determines the horizontal and vertical positions of the radiation source unit 14. The provisional positioning of the radiation source unit 14 may be performed, for example, using a table that pre-defines the relationship between the shooting area, shooting posture, shooting direction, and the position of the radiation source unit 14. The provisional positioning of the radiation source unit 14 can also be performed manually.

[0032] The information acquisition unit 71 causes the measurement unit 62 to measure the distance from the provisionally positioned radiation source unit 14 to the projection surface 41 of the screen 40. The measurement unit 62 generates distance information indicating the distance from the radiation source unit 14 to the projection surface 41. The information acquisition unit 71 acquires the distance information generated by the measurement unit 62.

[0033] The subject image acquisition unit 73 acquires the subject image transmitted from the console 30. The subject image is a radiographic image of the subject 50, which is the target of radiographic imaging, that was previously taken using a long-length imaging technique. The console 30 may also download the subject image from a medical information server (not shown). The downloaded subject image is stored in the storage medium (not shown) of the console 30.

[0034] The subject image selection unit 74 selects an image to be projected onto the projection surface 41 from among the subject images acquired by the subject image acquisition unit 73, based on the information indicating the shooting area, shooting posture, and shooting direction included in the shooting menu information acquired by the information acquisition unit 71. For example, if the shooting area, shooting posture, and shooting direction indicated by the shooting menu information are "chest," "standing," and "front," respectively, the subject image selection unit 74 selects an image from among the subject images acquired by the subject image acquisition unit 73 whose shooting area, shooting posture, and shooting direction are "chest," "standing," and "front," respectively. Metadata indicating the shooting area, shooting posture, and shooting direction may be attached to each subject image. In this case, the subject image selection unit 74 may refer to the metadata to identify the shooting area, shooting posture, and shooting direction for that subject image.

[0035] The subject image processing unit 75 derives the range of the subject 50 depicted in the radiation image based on the radiation emitted from the radiation source unit 14, based on distance information acquired by the information acquisition unit 71. Figure 5 is a diagram showing the relationship between the distance from the radiation source unit 14 to the projection surface 41 and the range of the subject 50 depicted in the radiation image based on the radiation emitted from the radiation source unit 14. As shown in Figure 5, when a radiation image of the subject 50 is taken, the screen 40 is placed in front of the detection panel 21, and the subject 50 is positioned in front of the screen 40. The shorter the distance from the radiation source unit 14 to the projection surface 41, the narrower the irradiation range of the radiation that passes through the subject 50. As a result, the range of the subject 50 depicted in the radiation image becomes narrower. The distance from the radiation source unit 14 to the subject 50 and the distance from the radiation source unit 14 to the detection panel 21 can be estimated from the distance from the radiation source unit 14 to the projection surface 41, which is indicated by the distance information. Therefore, it is possible to derive the rendering range of the subject 50 based on distance information.

[0036] The subject image processing unit 75 derives the range of the subject 50 to be depicted in the radiation image based on distance information, the size of the radiation field (opening of the radiation field limiter), the height position of the radiation source unit 14, and the body size information of the subject 50. There are no particular limitations on how the range of depiction is defined, but for example, the range of depiction may be defined by sequential numbers assigned at predetermined intervals to each part of the subject 50 along the longitudinal direction in long-length imaging. The sequential numbers may be assigned, for example, with the top of the subject 50's head as "0" and increasing by 1 at 1 cm intervals along the longitudinal direction. The sequential numbers are like the markings on a ruler. Figure 5 shows an example in which the range of depiction is derived as "72-125" when the distance from the radiation source unit 14 to the projection plane 41 is relatively short, and in which the range of depiction is derived as "15-153" when the distance from the radiation source unit 14 to the projection plane 41 is relatively long.

[0037] The subject image processing unit 75 trims the subject image acquired by the subject image acquisition unit 73 based on the derived depiction range. As described above, the shorter the distance from the radiation source unit 14 to the projection plane 41, the narrower the depiction range of the subject 50 depicted in the radiation image. It is assumed that the subject image may depict the subject 50 over a wider area than the depiction range derived based on the distance information. The subject image processing unit 75 performs trimming by cutting out the area from the subject image that corresponds to the depiction range derived based on the distance information. For example, each part of the subject image along the longitudinal direction may be assigned a number corresponding to a sequential number used to identify the depiction range derived based on the distance information, and the area that matches the range of the sequential number indicating the depiction range derived based on the distance information may be cut out from the subject image. Alternatively, the subject image processing unit 75 may perform trimming by outlining the partial image in the original image instead of cutting out the partial image contained in the original image from the original image.

[0038] The subject image processing unit 75 sets the projection size of the subject image based on the body size information and distance information acquired by the information acquisition unit 71. That is, the subject image processing unit 75 sets the projection size of the subject image so that when the projector 61 projects the subject image onto the projection surface 41 from a position separated from the projection surface 41 by the distance indicated by the distance information, the subject image projected onto the projection surface 41 is the actual size. The subject image processing unit 75 enlarges or reduces the size of the subject image so that the size of the subject image projected onto the projection surface 41 matches the dimensions of the subject 50's height, chest circumference, waist circumference, or other body parts indicated by the body size information. If the projector 61 has a zoom function, the projection size of the subject image may also be set using the zoom function of the projector 61.

[0039] The subject image projection unit 76 processes the subject image, which has been trimmed by the subject image processing unit 75, to project onto the projector 61 at a set projection size. As a result, the trimmed subject image is projected onto the projection surface 41 at its actual size. Figure 6 shows an example of the subject image 300 projected onto the projection surface 41.

[0040] Figure 7 is a flowchart illustrating an example of the flow of the shooting support process performed by the processor 17 executing the shooting support program 200. The shooting support program 200 is executed, for example, when the user instructs the start of the process from the console 30. Typically, the shooting support process is performed before positioning the subject 50, that is, before placing the subject 50 in front of the screen 40.

[0041] In step S1, the information acquisition unit 71 acquires shooting menu information and subject information transmitted from the console 30. The shooting menu information includes information indicating the shooting area, shooting posture and shooting direction of the subject 50, as well as the body size information of the subject 50. The subject information includes body size information indicating the body size of the subject 50.

[0042] In step S2, the position control unit 72 provisionally positions the radiation source unit 14 based on the imaging menu information acquired in step S1. That is, the position control unit 72 controls the travel unit 12 and support unit 13 of the radiation generator 10 to move the radiation source unit 14 to a position determined according to the imaging area, imaging posture, and imaging direction. This provisionally determines the height and horizontal position of the radiation source unit 14.

[0043] In step S3, the information acquisition unit 71 obtains distance information indicating the distance from the radiation source unit 14 to the projection surface 41 by having the measurement unit 62 measure the distance from the radiation source unit 14 to the screen 40.

[0044] In step S4, the subject image acquisition unit 73 acquires the subject image transmitted from the console 30. The subject image is a radiographic image of the subject 50, which is the subject of the radiographic image, that was previously taken using the long-length radiographic technique.

[0045] In step S5, the subject image selection unit 74 selects an image from the subject images acquired in step S4 to be projected onto the projection surface 41, based on the information indicating the shooting area, shooting posture, and shooting direction included in the shooting menu information acquired in step S1.

[0046] In step S6, the subject image processing unit 75 derives the range of depiction of the subject 50, which is depicted in the radiation image based on the radiation emitted from the radiation source unit 14, based on the distance information acquired in step S3.

[0047] In step S7, the subject image processing unit 75 trims the subject image acquired in step S4 based on the rendering range derived in step S6. For example, the subject image processing unit 75 performs trimming by cutting out the area corresponding to the rendering range derived in step S6 from the subject image acquired in step S4.

[0048] In step S8, the subject image processing unit 75 sets the projection size of the subject image that was cropped in step S7, based on the body size information included in the subject information acquired in step S1 and the distance information acquired in step S3. That is, the subject image processing unit 75 sets the projection size of the subject image so that when the projector 61 projects the subject image onto the projection surface 41 from a position separated from the projection surface 41 by the distance indicated by the distance information, the subject image projected onto the projection surface 41 is the actual size.

[0049] In step S9, the subject image projection unit 76 processes the subject image, which was trimmed in step S7, to be projected onto the projector 61 at the projection size set in step S8. As a result, the trimmed subject image is projected onto the projection surface 41 at its actual size.

[0050] As described above, the radiation imaging system 100 according to the embodiment of the disclosed technology includes a radiation generator 10 having a radiation source 14 that emits radiation, a projector 61 that projects an image in the direction of radiation emission, and a processor 17. The processor 17 acquires distance information indicating the distance from the radiation source 14 to the projection surface 41 and a subject image which is a radiation image of the subject 50 taken in the past. Based on the distance information, the processor 17 derives the range of the subject 50 to be depicted in the radiation image based on the radiation emitted from the radiation source 14, which is to be taken of the subject 50. Based on the range of depiction, the processor 17 trims the subject image and projects the trimmed subject image onto the projector 61.

[0051] In long-length radiography, the radiation source is positioned with the patient in a specific location so that the desired area is included in a series of radiographic images. For example, if the distance between the radiation source and the patient is too close, the desired area may not be captured even with long-length radiography. Positioning the radiation source in long-length radiography takes more time than in general radiography. Depending on the patient's illness or injury, it may be difficult for the patient to maintain a specific posture (e.g., standing) for an extended period of time in accordance with the radiography procedure.

[0052] According to the radiation imaging system 100 of the disclosed technology embodiment, it is possible to support the work performed when taking radiation images. Specifically, it is possible to understand the range of the subject 50 to be depicted in the radiation image before positioning the subject 50. Therefore, it is possible to determine whether the position of the radiation source 14 is appropriate before positioning the subject 50, and to correct the position of the radiation source 14 as necessary. By completing some of the work performed when taking radiation images before positioning the subject 50, the burden on the subject 50 can be reduced.

[0053] In this embodiment, the example shows that all the processes shown in Figure 7 are performed by the processor 17 of the radiation generator 10. However, at least some of these processes may be performed by the processor (not shown) of the console 30. For example, at least one of the processes shown in Figure 7—the process of selecting the subject image (step S5), the process of deriving the subject's display range (step S6), the process of cropping the subject image (step S7), and the process of setting the projection size of the subject image (step S8)—may be executed by the processor of the console 30.

[0054] [Second Embodiment] Figure 8 is a functional block diagram showing an example of the functional configuration of the radiation generator 10 when the processor 17 of the radiation generator 10 according to the second embodiment of the disclosed technology performs imaging support processing (see Figure 9) in accordance with the imaging support program 200. The processor 17 differs from the first embodiment described above in that it further functions as an emission condition derivation unit 77 and an emission control unit 78.

[0055] The information acquisition unit 71 according to the second embodiment acquires determined distance information, which indicates the distance determined as the distance from the radiation source unit 14 to the projection plane 41. The determined distance information is information indicating the distance from the radiation source unit 14 to the projection plane 41 when the radiation source unit 14 is positioned at the determined position for taking a radiation image. The determined distance information can be acquired by having the measurement unit 62 measure the distance while the radiation source unit 14 is positioned at the determined position.

[0056] Furthermore, the information acquisition unit 71 according to the second embodiment acquires range specification information that specifies the range of the subject 50 to be depicted in the radiographic image taken of the subject 50. There are no particular limitations on how the range of the subject 50 to be depicted in the radiographic image is defined, but for example, the range of the subject 50 to be depicted in the radiographic image may be defined by sequential numbers assigned at predetermined intervals to each part of the subject 50 along the longitudinal direction in long-length imaging.

[0057] The emission condition derivation unit 77 derives the emission conditions for radiation based on the determined distance information and the range specification information. That is, the emission condition derivation unit 77 derives the number of radiation emission cycles and the rotation angle range of the radiation source unit 14 so that when radiation is emitted from a position separated from the projection plane 41 by the distance indicated by the determined distance information, the range of the subject 50 indicated by the range specification information is included in a series of radiation images obtained by long-length imaging. The shorter the distance from the radiation source unit 14 to the projection plane 41, and the wider the range of the subject 50 to be depicted in the radiation image, the more radiation emission cycles and the wider the rotation angle range of the radiation source unit 14 becomes. The emission condition derivation unit 77 may further derive the tube current and tube voltage based on the determined distance information.

[0058] When the emission control unit 78 receives an instruction to start emitting radiation, it controls the timing of each emission of radiation, which is emitted for the number of times derived by the emission condition derivation unit 77. The emission control unit 78 rotates the radiation source unit 14 within the rotation angle range derived by the emission condition derivation unit 77, and controls the emission of radiation from the radiation source unit 14 when the radiation source unit 14 is positioned at a predetermined rotation angle.

[0059] Figure 9 is a flowchart showing an example of the flow of imaging support processing performed by the processor 17 according to the second embodiment, when it executes the imaging support program 200. In the flowchart shown in Figure 9, the processing from step S1 to step S9 is the same as in the first embodiment described above, so a description of these processes will be omitted.

[0060] In step S10, the information acquisition unit 71 acquires determined distance information indicating the distance determined as the distance from the radiation source unit 14 to the projection plane 41.

[0061] In step S11, the information acquisition unit 71 acquires range specification information that specifies the range of the subject 50 that should be depicted in the radiographic image taken of the subject 50.

[0062] In step S12, the emission condition derivation unit 77 derives the radiation emission conditions based on the determined distance information acquired in step S10 and the range specification information acquired in step S11. That is, the emission condition derivation unit 77 derives the number of radiation emission times and the rotation angle range of the radiation source unit 14 so that when radiation is emitted from a position separated from the projection plane 41 by the distance indicated by the determined distance information, the range of the subject 50 indicated by the range specification information is included in a series of radiation images obtained by long-length imaging.

[0063] In step S13, the emission control unit 78 determines whether or not there is an instruction to start emitting radiation. The instruction to start emitting radiation can be given, for example, by the user operating the console 30.

[0064] In step S14, the emission control unit 78 controls the emission timing of each emission of radiation, which is emitted for the number of times derived by the emission condition derivation unit 77. The emission control unit 78 rotates the radiation source unit 14 within the rotation angle range derived in step S12, and controls the emission of radiation from the radiation source unit 14 when the radiation source unit 14 is positioned at a predetermined rotation angle.

[0065] According to the radiation generator 10 of the second embodiment of the disclosed technology, it becomes possible to perform long-length imaging under appropriate imaging conditions according to the position of the radiation source 14. In other words, it becomes possible to promote the effect of supporting the work performed when taking radiation images.

[0066] In the above embodiment, for example, the hardware structure of the processing unit that performs various processes such as the information acquisition unit 71, position control unit 72, subject image acquisition unit 73, subject image selection unit 74, subject image processing unit 75, subject image projection unit 76, emission condition derivation unit 77, and emission control unit 78 can be the various processors shown below. As mentioned above, the various processors include CPUs and GPUs, which are general-purpose processors that execute software (programs) and function as various processing units, as well as programmable logic devices (PLDs), such as FPGAs, whose circuit configuration can be changed after manufacturing, and dedicated electrical circuits, such as ASICs (Application Specific Integrated Circuits), which have circuit configurations specifically designed to perform specific processes.

[0067] A single processing unit may consist of one of these various processors, or it may consist of a combination of two or more processors of the same or different types (for example, a combination of multiple FPGAs, or a combination of a CPU and an FPGA). Alternatively, multiple processing units may be composed of a single processor.

[0068] Examples of configuring multiple processing units with a single processor include, firstly, a configuration where one or more CPUs and software combine to form a single processor, which then functions as multiple processing units, as exemplified by client and server computers. Secondly, a configuration using a processor that realizes the functions of the entire system, including multiple processing units, on a single IC (Integrated Circuit) chip, as exemplified by System on Chip (SoC). Thus, various processing units are configured, in terms of hardware structure, using one or more of the above-mentioned processors.

[0069] Furthermore, the hardware structure of these various processors can more specifically utilize electrical circuits, which are combinations of circuit elements such as semiconductor devices.

[0070] Furthermore, although the above embodiment describes an configuration in which the editing program 111 and the pressure derivation program 112 are pre-stored (installed) in the non-volatile memory 103, the embodiment is not limited to this. These programs may be provided in the form of recordings on recording media such as CD-ROM (Compact Disc Read Only Memory), DVD-ROM (Digital Versatile Disc Read Only Memory), and USB (Universal Serial Bus) memory. These programs may also be provided in the form of downloads from external devices via a network. In other words, the programs described in this embodiment (i.e., program products) may be provided on recording media or distributed from external computers.

[0071] The following additional information is disclosed regarding the first and second embodiments described above. (Note 1) A radiation generator having a radiation source that emits radiation, A projector that projects an image in the direction of radiation emission, At least one processor, It has, The aforementioned processor, Distance information indicating the distance from the radiation source to the projection surface on which the image is projected is obtained. For the subject of the radiographic image, we obtain the subject image, which is a radiographic image taken in the past. Based on the distance information, the range of the subject depicted in the radiation image, which is captured with respect to the subject and is based on the radiation emitted from the radiation source, is derived. Based on the aforementioned depiction range, the subject image is cropped. The cropped image of the subject is projected onto the projector. Radiation imaging system.

[0072] (Note 2) The system further includes a measuring unit for measuring the distance from the radiation source to the projection surface. The radiographic imaging system described in Appendix 1.

[0073] (Note 3) The aforementioned processor, When taking a radiographic image of the subject, posture information indicating the shooting posture of the subject is acquired. Select the subject image based on the posture information. A radiation generating device as described in Appendix 1 or Appendix 2.

[0074] (Note 4) The aforementioned processor, Subject information including body size information indicating the physique of the subject is obtained. The projection size of the subject image is set based on the aforementioned body information. A radiation generating device as described in any one of the appendices 1 through 3.

[0075] (Note 5) The aforementioned processor, Obtain confirmed distance information indicating the distance determined as the distance to the projection surface, A range specification information is obtained that specifies the range of the subject to be depicted in the radiographic image taken of the subject. Based on the aforementioned determined distance information and the aforementioned range specification information, the radiation emission conditions are derived. A radiation generating device as described in any one of the appendices 1 through 4.

[0076] (Note 6) The emission conditions include the number of times radiation is emitted from the radiation source. Radiation generating device as described in Appendix 5.

[0077] (Note 7) The aforementioned processor, Based on the confirmed distance information and the range specification information, the timing of each emission of radiation emitted from the radiation source is controlled. Radiation generating device as described in Appendix 6. [Explanation of symbols]

[0078] 10. Radiation Generator 11 Guide rails 12. Running section 13 Post section 14 Source section 15 Drive mechanism 16 Communication Interfaces 17 Processors 18 RAM 19 Non-volatile memory 20. Radiation detection device 21 detection panel 22 Pillar section 30 Console 31 displays 32 Input Devices 40 Folding screens 41 Projection plane 50 subjects 61 Projector 62 Measuring part 71 Information Acquisition Department 72 Position Control Unit 73 Subject image acquisition unit 74 Subject Image Selection Section 75 Subject Image Processing Unit 76 Subject image projection section 77 Ejection condition derivation section 78 Injection Control Unit 100 Radiation imaging systems 200 Photography Support Programs 300 subject images

Claims

1. A radiation generator having a radiation source that emits radiation, A projector that projects an image in the direction of radiation emission, At least one processor, It has, The aforementioned processor, Distance information indicating the distance from the radiation source to the projection surface on which the image is projected is obtained. For the subject of the radiographic image, we obtain the subject image, which is a radiographic image taken in the past. Based on the distance information, the range of the subject depicted in the radiation image, which is captured with respect to the subject and is based on the radiation emitted from the radiation source, is derived. Based on the aforementioned depiction range, the subject image is cropped. The cropped image of the subject is projected onto the projector. Radiation imaging system.

2. The system further includes a measuring unit for measuring the distance from the radiation source to the projection surface. The radiation imaging system according to claim 1.

3. The aforementioned processor, When taking a radiographic image of the subject, posture information indicating the shooting posture of the subject is acquired. Select the subject image based on the posture information. The radiation imaging system according to claim 1.

4. The aforementioned processor, Subject information including body size information indicating the physique of the subject is obtained. The projection size of the subject image is set based on the aforementioned body information. The radiation imaging system according to claim 1.

5. The aforementioned processor, Obtain confirmed distance information indicating the distance determined as the distance to the projection surface, A range specification information is obtained that specifies the range of the subject to be depicted in the radiographic image taken of the subject. Based on the aforementioned determined distance information and the aforementioned range specification information, the radiation emission conditions are derived. A radiographic imaging system according to any one of claims 1 to 4.

6. The emission conditions include the number of times radiation is emitted from the radiation source. The radiation imaging system according to claim 5.

7. The aforementioned processor, Based on the confirmed distance information and the range specification information, the timing of each emission of radiation emitted from the radiation source is controlled. The radiation imaging system according to claim 6.

Images