Photography assist device, operating method thereof, and computer-readable storage medium

Abstract

A radiographic assist device for use with a radiographic apparatus having a radiation source and a radiographic image detector for detecting a radiographic image of a subject based on radiation irradiated from the radiation source and transmitted through the subject. The radiographic assist device comprises: an optical camera for optically imaging an area including an irradiation field of radiation irradiated from the radiation source to the subject; and at least one processor. The processor performs the following processing: acquiring an optical image showing the subject within the area as a first optical image by coordinating imaging by the optical camera with imaging by the radiographic apparatus; and storing the radiographic image acquired by the radiographic imaging in association with the first optical image in a storage unit.

Description

Technical Field

[0001] The technology of the present invention relates to a photography assisting device, an operating method thereof, and a computer-readable storage medium. Background Art

[0002] In radiographic systems used in the medical field, as preparation for radiography, after a radiographer or doctor (hereinafter referred to as a technician, etc.) positions the radiographic part of the subject, radiography is performed according to the instructions of the technician, etc. However, after the radiographic part is positioned relative to the radiation field and before radiography is performed, the position of the radiographic part may shift due to movement of the subject, and it may sometimes be impossible to obtain the desired image of the radiographic part. Thus, the situation in which the desired radiographic image cannot be obtained by radiography, that is, the situation in which radiography fails, is called "radiographic loss". When radiographic loss occurs, re-radiation is performed. Re-radiation requires time and effort, so it is better to perform re-radiation as little as possible.

[0003] For example, in the radiographic system described in Japanese Patent Application Laid-Open No. 2011-24721, re-radiation is suppressed by providing an optical camera that captures an optical image of the subject. In the radiographic system described in Japanese Patent Application Laid-Open No. 2011-24721, when performing radiography, a technician or the like first positions the radiographic portion while guiding the subject. The optical camera then captures the current position of the radiographic portion. Immediately before radiography, the optical camera captures the current position of the radiographic portion. The positioning image captured by the optical camera during radiographic portion positioning is compared with the current image captured by the camera immediately before radiography, allowing the technician or the like to visually confirm whether the radiographic portion has shifted. Since radiography can be performed after this confirmation, unnecessary re-radiation is suppressed. Summary of the Invention

[0004] Technical issues to be solved by the invention

[0005] However, there is also a slight positional offset, that is, even if the technicians and others believe that the positioning is accurate depending on the photographic part, it is not actually accurately positioned, resulting in a photographic loss. For example, when diagnosing the state of the knee joint based on a radiographic image with the knee as the photographic part, it is necessary to clearly depict the joint cavity (the gap between bones) in the radiographic image. However, radiation is a beam of rays that diverge radially from the focus of the radiation source, so sometimes the incident angle of the radiation changes due to a slight positional offset of the joint, causing the depiction of the joint cavity to become unclear. When the depiction of the joint cavity is unclear, it becomes a photographic loss and requires re-photography.

[0006] When a retake due to a loss of image quality requires re-shooting, technicians must reposition the subject. When reshooting, slight positional deviations of the subject can usually be corrected by making fine adjustments based on the subject's position at the time of the loss of image quality. However, if the subject has moved significantly since the time of the loss of image quality, technicians will not be able to accurately determine the subject's position at the time of the loss of image quality, making fine adjustments impossible. Repositioning the subject from scratch without using the position at the time of the loss of image quality as a reference increases the likelihood of further loss of image quality.

[0007] It is also conceivable to adjust the position of the subject based on the radiographic image at the time of the imaging loss when re-shooting is performed. However, the radiographic image does not depict the appearance of the subject, so it is not realistic to adjust the position of the subject based on the radiographic image.

[0008] As described above, re-shooting may be unavoidable depending on the imaging site. However, if the position adjustment during re-shooting is not properly performed, there is a high possibility that imaging loss will occur again even if re-shooting is performed, and re-shooting may be repeated.

[0009] The technical object of the present invention is to provide a photography assistance device, an operating method thereof, and an operating program thereof that can suppress repeated re-photography.

[0010] Means for solving technical problems

[0011] To achieve the above-mentioned object, the present invention provides an imaging assist device for use in a radiographic apparatus having a radiation source and a radiation image detector for detecting a radiographic image of a subject based on radiation irradiated from the radiation source and transmitted through the subject. The imaging assist device comprises: an optical camera for optically imaging an area including an irradiation field of radiation irradiated from the radiation source to the subject; and at least one processor. The processor performs the following processing: acquiring an optical image showing the subject within the area as a first optical image by coordinating imaging by the optical camera with imaging by the radiographic apparatus; and storing the radiographic image acquired by the radiographic imaging in association with the first optical image in a storage unit.

[0012] Preferably, the processor performs the following processing: after performing radiographic imaging, performing imaging with an optical camera to acquire an optical image showing a subject within the area as a second optical image; and superimposing the first optical image on the second optical image to display the image on the display unit.

[0013] Preferably, the first optical image is a still image and the second optical image is a moving image, and the processor superimposes the second optical image on the first optical image to display the image on the display unit in real time.

[0014] Preferably, the processor performs processing to: detect a positional deviation amount of the subject in the first optical image and the second optical image through image processing; and supply information on the positional deviation amount to the notification unit.

[0015] Preferably, the notification unit is a display unit, and the processor displays on the display unit a direction for moving the position of the subject toward the position indicated by the first optical image based on the positional offset.

[0016] The processor may cause the notification unit to output a warning when the positional deviation amount is equal to or greater than a predetermined value.

[0017] It is also preferable that the radiographic apparatus includes a moving mechanism for moving an irradiation field of radiation, and the processor controls the moving mechanism to move the irradiation field in a direction that reduces the amount of positional deviation.

[0018] It is preferred that the optical camera performs photography based on visible light or infrared light.

[0019] It is also preferable to include a projector that projects the first optical image onto the radiation image detector.

[0020] The present invention provides a method for operating a photography assisting device, wherein the photography assisting device is used for a radiographic device, wherein the radiographic device comprises a radiation source and a radiographic image detector for detecting a radiographic image of a subject based on radiation irradiated from the radiation source and transmitted through the subject, wherein the photography assisting device comprises an optical camera for optically photographing an area of an irradiation field including radiation irradiated from the radiation source to the subject, and wherein the method for operating the photography assisting device comprises the following steps: acquiring an optical image of a subject within the area by linking photography based on the optical camera with radiographic photography based on the radiographic device; and associating the radiographic image and the optical image acquired by radiographic photography and storing them in a storage unit.

[0021] The working procedure of the present invention causes a photography auxiliary device to operate, wherein the photography auxiliary device is used for a radiographic device, wherein the radiographic device has a radiation source and a radiographic image detector that detects a radiographic image of a subject based on radiation irradiated from the radiation source and transmitted through the subject. The photography auxiliary device has an optical camera that optically photographs an area of an irradiation field including radiation irradiated from the radiation source to the subject, and at least one processor. The working procedure causes the processor to perform the following processing: acquiring an optical image of a subject within the area by linking photography based on the optical camera with radiographic photography based on the radiographic device; and associating the radiographic image and the optical image acquired by radiographic photography and storing them in a storage unit.

[0022] Effects of the Invention

[0023] According to the technology of the present invention, it is possible to provide a photography assistance device capable of suppressing repeated re-photography, and an operating method and an operating program thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a diagram showing the configuration of an X-ray imaging system.

[0025] Figure 2 This is a three-dimensional diagram of the appearance of the electronic dark box.

[0026] Figure 3 This is a block diagram showing the structure of a console.

[0027] Figure 4 This is a diagram illustrating a photography order.

[0028] Figure 5 This is a diagram illustrating an example condition table.

[0029] Figure 6 exemplifies associated X-ray images and still images.

[0030] Figure 7 This is a block diagram showing the functional units constituting the CPU.

[0031] Figure 8 This is a diagram for explaining the superimposition process.

[0032] Figure 9 This is a diagram for explaining positional deviation detection.

[0033] Figure 10 exemplifies overlapping images.

[0034] Figure 11 It is a diagram showing a modified example of the arrow displayed on the superimposed image.

[0035] Figure 12This is a flowchart illustrating the processing procedure of the CPU.

[0036] Figure 13 The diagram exemplifies a screen of a display displaying an X-ray image.

[0037] Figure 14 This figure explains how to input a reason for photographic loss.

[0038] Figure 15 This is a diagram schematically showing how the visibility of the joint cavity decreases due to the rotation of the knee.

[0039] Figure 16 This is a diagram schematically showing how the visibility of the joint cavity decreases due to the parallel movement of the knee.

[0040] Figure 17 The diagram exemplifies a screen of a display displaying an overlapping image.

[0041] Figure 18 This is a diagram illustrating problems in the conventional technology.

[0042] Figure 19 It is a diagram for explaining the effects of the technology based on the present invention.

[0043] Figure 20 This is a flowchart illustrating a warning generation process based on a positional deviation amount.

[0044] Figure 21 This is a block diagram showing each functional unit of a CPU according to a modification.

[0045] Figure 22 This is a diagram for explaining movement control of the irradiation field.

[0046] Figure 23 It is a diagram showing the configuration of an X-ray imaging system according to the second embodiment.

[0047] Figure 24 This is a block diagram showing each functional unit of the CPU according to the second embodiment.

[0048] Figure 25 3 is a diagram illustrating an example of a projection image projected onto the electronic cassette.

[0049] Figure 26 It is a diagram showing the configuration of an X-ray imaging system according to a third embodiment.

[0050] Figure 27 This is a block diagram showing each functional unit of the CPU according to the third embodiment.

[0051] Figure 28This is a flowchart (part 1) illustrating the processing procedure of the CPU according to the third embodiment.

[0052] Figure 29 This is a flowchart (part 2) illustrating the processing procedure of the CPU according to the third embodiment.

[0053] Figure 30 This is a diagram illustrating a screen image during reshooting preparation in the third embodiment.

[0054] Figure 31 This is a diagram showing another display example of the screen during reshooting preparation in the third embodiment. DETAILED DESCRIPTION

[0055] [First embodiment]

[0056] exist Figure 1 In the present embodiment, an X-ray imaging system 10 using X-rays as radiation includes an X-ray source 11, a source control device 12, an electronic cassette 13, a console 14, and an optical camera 15. In this embodiment, the console 14 and the optical camera 15 constitute an imaging auxiliary device. The X-ray source 11 is an example of a radiation source. The electronic cassette 13 is an example of a radiation image detector.

[0057] In the X-ray imaging system 10, the electronic cassette 13 is arranged at a position facing the X-ray source 11. By arranging the subject H between the X-ray source 11 and the electronic cassette 13, the imaging part ( Figure 1 The X-ray source 11 and the electronic cassette 13 constitute an X-ray imaging device. This X-ray imaging device is an example of a radiographic device.

[0058] The electronic cassette 13 may also be arranged using an imaging table. In the present embodiment, after the radiographer (hereinafter referred to as the technician) RG positions the subject H, the technician RG performs the X-ray imaging operation.

[0059] The X-ray source 11 includes an X-ray tube 11A for generating X-rays and a collimator 11B for defining an area irradiated with X-rays, i.e., an irradiation field RF. The X-ray source 11 may include a built-in irradiation field display light source (not shown) that emits irradiation field display light that indicates the irradiation field RF on the X-ray incident surface 13A of the electronic cassette 13.

[0060] The X-ray tube 11A includes a filament that emits thermal electrons and a target that radiates X-rays when the thermal electrons released from the filament collide with it. The collimator 11B, for example, is constructed by placing four X-ray-shielding lead plates on each side of the quadrilateral, creating a quadrilateral irradiation aperture in the center that transmits X-rays. The collimator 11B adjusts the size of the irradiation aperture by moving the lead plates to set the irradiation field RF.

[0061] The X-ray source control device 12 includes a touch panel 12A, a voltage generator 12B, and a control unit 12C. The touch panel 12A is operated by a technician RG to set X-ray irradiation conditions and the size of the irradiation aperture of the collimator 11B. X-ray irradiation conditions include the tube voltage and tube current applied to the X-ray source 11, as well as the X-ray irradiation time.

[0062] The voltage generator 12B generates a tube voltage to be applied to the X-ray tube 11A. The control unit 12C controls the operation of the voltage generator 12B to set the tube voltage, tube current, and X-ray irradiation time to the values set via the touch panel 12A. The control unit 12C includes a timer that starts counting when the X-ray tube 11A generates X-rays. For example, when the time measured by the timer reaches the irradiation time specified in the irradiation conditions, the control unit 12C stops the operation of the X-ray tube 11A. Furthermore, the control unit 12C activates the collimator 11B to set the size of its irradiation aperture to the size set via the touch panel 12A.

[0063] Furthermore, an irradiation switch 16 is connected to the control unit 12C via a cable or the like. The irradiation switch 16 is operated by the technician RG to start X-ray irradiation. When the irradiation switch 16 is operated, the source control device 12 causes the X-ray tube 11A to generate X-rays. This causes X-rays to be irradiated toward the irradiation field RF.

[0064] The electronic cassette 13 detects an X-ray image XP based on X-rays emitted from the X-ray source 11 and transmitted through the imaging site of the subject H. The electronic cassette 13 includes a wireless communication unit and a battery, and operates wirelessly. The electronic cassette 13 wirelessly transmits the detected X-ray image XP to the console 14. The X-ray image XP is an example of a radiographic image.

[0065] The X-ray source 11 is suspended vertically downward from the ceiling 2 of the radiography room. The X-ray source 11 is held by a suspension holding mechanism 17. The suspension holding mechanism 17 is attached to the ceiling 2 via a horizontal movement mechanism 18. The suspension holding mechanism 17 holds the X-ray source 11 so that it can be raised and lowered vertically (in the ±Z directions). The horizontal movement mechanism 18 holds the suspension holding mechanism 17 so that it can be moved along the X-ray irradiation axis of the X-ray source 11 (in the ±X directions) and in directions perpendicular to the X-ray irradiation axis (in the ±Y directions).

[0066] The suspension holding mechanism 17 and the horizontal movement mechanism 18 are each equipped with a motor (not shown), enabling manual or motorized movement of the X-ray source 11 in various directions. The operation of the suspension holding mechanism 17 and the horizontal movement mechanism 18 is controlled by a control unit 12C. Manual or motorized movement of the X-ray source 11 can be selected using a touch panel 12A. By moving the X-ray source 11, the position of the irradiation field RF can be adjusted.

[0067] The optical camera 15 is an optical digital camera composed of a CMOS (Complementary Metal Oxide Semiconductor) image sensor or a CCD (Charge Coupled Device) image sensor, and performs photography using visible light, for example. The optical camera 15 is capable of capturing both still and moving images. The optical axis of the optical camera 15 is parallel to the X-ray irradiation axis passing through the center of the irradiation field RF. The optical camera 15 captures an area including the irradiation field RF to generate an optical image. The optical image is an image showing the photographed portion of the subject H within the irradiation field RF. The optical image is, for example, a color still image or a moving image.

[0068] The optical camera 15 is mounted on the periphery of the X-ray source 11. Alternatively, the optical camera 15 may be built into the X-ray source 11 instead of being mounted on the periphery. Furthermore, the objective lens and imaging element of the optical camera 15 may be separate components. In this case, the objective lens may be mounted on the periphery of the X-ray source 11, while the imaging element may be built into a portion other than the X-ray source 11 (e.g., an arm supporting the X-ray source 11).

[0069] The optical camera 15 is connected to the console 14 via a wired or wireless connection. The console 14 functions as an imaging control device to control the imaging operation of the optical camera 15. In addition to enabling the optical camera 15 to capture still images in conjunction with X-ray imaging, the console 14 also enables the optical camera 15 to capture moving images during the imaging preparation period before the start of X-ray imaging. For example, the console 14 is located in an operating room adjacent to the imaging room where the X-ray source 11 is installed.

[0070] When the irradiation switch 16 is operated, the console 14 transmits a still image photography instruction signal to the optical camera 15. The optical camera 15 performs still image photography of an area including the irradiation field RF in accordance with the still image photography instruction signal input from the console 14. An optical image obtained by this still image photography (hereinafter referred to as a still image SP) is transmitted to the console 14.

[0071] When the technician RG performs an operation to start imaging preparations, the console 14 transmits a moving image imaging start signal to the optical camera 15. The optical camera 15 begins moving image imaging of an area including the irradiation field RF in response to the moving image imaging start signal input from the console 14. The optical image obtained by this moving image imaging (hereinafter referred to as the moving image MP) is transmitted to the console 14 in real time as a so-called live preview image during the moving image imaging.

[0072] exist Figure 2 In the embodiment, the electronic cassette 13 is composed of a sensor panel 20, a circuit unit 21, and a portable rectangular parallelepiped housing 22 that houses these components. The housing 22 has a size that complies with the international standard ISO (International Organization for Standardization) 4090:2001, and is substantially the same as that of a film cassette, an IP (Imaging Plate) cassette, or a CR (Computed Radiography) cassette.

[0073] The electronic cassette 13 is positioned so that its X-ray incident surface 13A, which is the upper surface of the housing 22, faces the X-ray source 11, and X-rays are irradiated onto the X-ray incident surface 13A. Although not shown, the housing 22 is also provided with a switch for switching the main power on / off, and indicators indicating the operating status of the electronic cassette 13, such as the remaining battery life and the completion of imaging preparations.

[0074] The sensor panel 20 is composed of a scintillator 20A and a photodetection substrate 20B. The scintillator 20A and the photodetection substrate 20B are stacked in this order when viewed from the X-ray incident surface 13A. The scintillator 20A contains a phosphor such as CsI:Tl (thallium-activated cesium iodide) or GOS (Gd2O2S:Tb, terbium-activated gadolinium oxysulfide), and converts X-rays incident through the X-ray incident surface 13A into visible light for emission. Alternatively, a sensor panel stacked in this order when viewed from the X-ray incident surface 13A can be used. Furthermore, a direct-conversion sensor panel can be used, which directly converts X-rays into signal charges using a photoconductive film such as amorphous selenium.

[0075] The light detecting substrate 20B detects visible light emitted from the scintillator 20A and converts it into electric charge. The circuit unit 21 controls the driving of the light detecting substrate 20B and generates an X-ray image XP based on the electric charge output from the light detecting substrate 20B.

[0076] A plurality of pixels are arranged in a two-dimensional matrix on the light detection substrate 20B. Each pixel photoelectrically converts visible light emitted by the scintillator 20A to generate and store electric charge. The electric charge stored in each pixel is converted into a digital signal by the circuit unit 21, thereby generating an X-ray image XP.

[0077] Furthermore, the electronic cassette 13 has, for example, a function for detecting the start of X-ray irradiation. This irradiation start detection function is implemented, for example, by an irradiation start detection sensor provided on the light detection substrate 20B. The irradiation start detection sensor is, for example, composed of a portion of a plurality of pixels arranged in a two-dimensional matrix. When the radiation dose signal periodically output from the irradiation start detection sensor exceeds a threshold, it is determined that X-ray irradiation has started.

[0078] Similarly to the X-ray source control device 12, the electronic cassette 13 includes a timer that begins counting upon detecting the start of X-ray irradiation. When the time measured by the timer reaches the irradiation time included in the irradiation conditions set by the console 14, the electronic cassette 13 determines that X-ray irradiation has ended. Thus, the electronic cassette 13 can detect an X-ray image XP based on the irradiated X-rays by performing X-ray detection operations only during the irradiation time included in the irradiation conditions.

[0079] The electronic cassette 13 also includes an image memory and a wireless communication circuit. The electronic cassette 13 stores the X-ray image XP generated by the circuit unit 21 in the image memory and transmits the X-ray image XP stored in the image memory to the console 14 via the wireless communication circuit.

[0080] exist Figure 3 In FIG. 1 , the console 14 includes a display 30 , an input device 31 , a CPU (Central Processing Unit) 32 , a storage device 34 , a memory 33 , and a communication unit 35 . These are connected to each other via a data bus 36 .

[0081] The display 30 is a display unit having a GUI (Graphical User Interface)-based operation function and displays various operation screens, X-ray images XP, and optical images (still images SP and moving images MP). The input device 31 is an input operation unit including a touch panel or a keyboard.

[0082] The storage device 34 is, for example, an HDD (Hard Disk Drive) array, and is either built into the console 14 or externally connected to the console 14. The external connection is via a cable or a network. The storage device 34 stores control programs such as an operating system, various application programs, and various data associated with these programs.

[0083] The memory 33 is a working memory used by the CPU 32 to execute processing. The CPU 32 loads programs stored in the storage device 34 into the memory 33 and executes processing according to the programs, thereby centrally controlling various components of the console 14. The communication unit 35 transmits and receives various data, such as X-ray images XP and optical images (still images SP and moving images MP), with the electronic cassette 13 and the optical camera 15. Furthermore, the communication unit 35 communicates with the control unit 12C of the X-ray source control device 12.

[0084] Console 14 receives Figure 4 Input of an imaging order 37 is shown. The imaging order 37 is information for, for example, a client of an imaging department to instruct a technician RG to perform an X-ray imaging. The imaging order 37 is transmitted to the console 14 from, for example, a radiology information system (RIS) (not shown).

[0085] Photography orders 37 include items such as an order ID (Identification Data), a subject ID, and a photography technique. The order ID is a tag or number that identifies each photography order 37 and is automatically assigned by the RIS. The subject ID field contains the subject ID of the subject H to be photographed. The subject ID is a tag or number that identifies each subject H.

[0086] The photographic technique is information related to the photographic part of the subject H, the posture and direction of the photographic part. Figure 1 In addition to the knees shown in the example, other areas of interest include the head, cervical spine, chest, abdomen, hands, fingers, and elbows. Posture refers to the posture of the subject H, such as standing, lying, or sitting. Orientation refers to the orientation of the subject H relative to the X-ray source 11, such as the front, side, or back. In addition to these items, the radiography order 37 also includes subject information such as the name, gender, age, height, and weight of the subject H.

[0087] The storage device 34 of the console 14 stores Figure 5 The condition table 38 is shown. In the condition table 38, corresponding irradiation conditions are registered in association with each imaging technique.

[0088] The console 14 is operated by the technician RG and the display 30 displays the Figure 4 The contents of the photography order 37 are tabulated and obtained as shown in FIG. The technician RG can check the contents of the photography order 37 by browsing the photography order list. Figure 5 The contents of the condition table 38 are displayed on the display 30. The technician RG can select and set the irradiation conditions that match the imaging technique specified in the imaging order 37.

[0089] The console 14 wirelessly transmits a condition setting signal including various information such as the irradiation conditions set by the technician RG, the order ID, and the console ID which is identification information of the console to the electronic cassette 13 .

[0090] The console 14 converts the X-ray image XP received from the electronic cassette 13 into an image file in a format compliant with the DICOM (Digital Imaging and Communication in Medicine) standard, for example, and stores it in the storage device 34, which serves as a storage unit. The image file is a file in which the X-ray image XP and accompanying information are associated via a single image ID. The accompanying information includes the order ID, subject ID, imaging technique, irradiation conditions, and the like.

[0091] Furthermore, an image ID (optical image ID) associated with the image ID (X-ray image ID) of the X-ray image XP obtained by the X-ray imaging is assigned to the still image SP obtained by the optical camera 15 in conjunction with the X-ray imaging. Figure 6 As shown, the X-ray image XP and the still image SP obtained during one X-ray imaging are associated with the X-ray image ID and the optical image ID and stored in the storage device 34 .

[0092] When the imaging technique is "knee / flexed posture / side view", the doctor diagnoses the joint cavity JC of the knee based on the X-ray image XP. Therefore, the joint cavity JC must be clearly depicted in the X-ray image XP.

[0093] exist Figure 7 In the storage device 34, a work program 40 is stored. Figure 5 The condition table 38 shown is also stored in the storage device 34. The CPU 32 executes the operation program 40 to form a plurality of functional units.

[0094] The work program 40 causes the CPU 32 to function as a still image shooting instruction unit 41, a still image acquisition unit 42, an association establishment unit 43, a moving image shooting instruction unit 44, a moving image acquisition unit 45, an overlay processing unit 46, a display control unit 47, a position shift detection unit 48 and a notification information generation unit 49.

[0095] The still image imaging instruction unit 41 receives the X-ray irradiation start signal ES, which is generated by the control unit 12C of the X-ray source control device 12 and supplied to the voltage generator 12B in response to the pressing of the irradiation switch 16. Upon receiving the X-ray irradiation start signal ES, the still image imaging instruction unit 41 instructs the optical camera 15 to perform still image imaging.

[0096] The still image acquisition unit 42 acquires a still image SP generated by still image photography performed by the optical camera 15. The still image SP acquired by the still image acquisition unit 42 is input to the association unit 43. Furthermore, the association unit 43 receives, via the communication unit 35, an X-ray image XP detected by the electronic cassette 13 based on X-rays emitted from the X-ray source 11 when the irradiation switch 16 is pressed.

[0097] The correlating section 43 associates the still image SP input to the still image acquiring section 42 and the X-ray image XP input from the electronic cassette 13 as follows: Figure 6 The data are associated as shown and stored in the storage device 34 .

[0098] In response to the input of the re-radiograph preparation start signal RS from the input device 31, the dynamic image capture instructing unit 44 transmits a dynamic image capture start signal instructing the optical camera 15 to begin dynamic image capture. Furthermore, when the technician RG, after reviewing the X-ray image XP acquired through X-ray imaging, determines that the image is not captured, he or she operates the input device 31 to shift the imaging assistance device to a re-radiograph preparation mode. For example, if the radiographic technique is "knee / flexed position / lateral view," the technician RG determines that the image is not captured if the knee joint cavity JC is not clearly depicted in the X-ray image XP.

[0099] The moving image acquisition unit 45 acquires, frame by frame, in real time, a moving image MP generated by moving image photography performed by the optical camera 15. The moving image MP acquired by the moving image acquisition unit 45 is input to the superimposition processing unit 46 frame by frame.

[0100] The superimposition processing unit 46 obtains the still image SP stored in the storage device 34 and Figure 8 As shown, a still image SP is superimposed on each frame of the moving image MP. The superimposition processing unit 46 inputs the superimposed image TP generated by superimposing the moving image MP and the still image SP to the display control unit 47 frame by frame. The display control unit 47 displays the superimposed image TP on the display 30 frame by frame. In other words, the display control unit 47 superimposes the still image SP on the moving image MP and displays it on the display 30 in real time.

[0101] The still image SP in the superimposed image TP is associated with the X-ray image XP determined by the technician RG to be an imaging loss, and is an example of a first optical image showing the position of the subject H at the time of the imaging loss. The moving image MP in the superimposed image TP is an example of a second optical image showing the current position of the subject H in preparation for re-radiation. Therefore, by checking the superimposed image TP displayed in real time on the monitor 30, the technician RG can confirm the current position of the subject H relative to the time of the imaging loss.

[0102] The moving image photography by the optical camera 15 ends upon receipt of a still image photography execution instruction from the aforementioned still image photography instruction unit 41. The still image acquisition unit 42 may acquire one frame of the moving image MP as a still image SP.

[0103] The position shift detecting unit 48 operates similarly to the superimposition processing unit 46 during the period when the optical camera 15 is shooting a moving image. The moving image MP acquired by the moving image acquiring unit 45 is input to the position shift detecting unit 48 frame by frame. The position shift detecting unit 48 acquires the still image SP stored in the storage device 34 and Figure 9 As shown, the positional offset between each frame of the moving image MP and the subject H in the still image SP is detected by image processing. The positional offset detection unit 48 detects the positional offset by obtaining a motion vector using, for example, a block matching method.

[0104] The positional offset detection unit 48 may also detect the amount of positional offset using a machine learning method utilizing a neural network. For example, the positional offset detection unit 48 can detect the amount of positional offset by extracting feature quantities from each of the moving image MP and the still image SP using a convolutional neural network. By using various images of the subject H as training data, the neural network can accurately detect positional offsets caused not only by parallel movement of the subject H but also by rotation or swivel.

[0105] The notification information generating unit 49 generates a direction (vector) as notification information for moving the current position of the subject H shown in the moving image MP toward the position of the subject H at the time of the loss of photography shown in the still image SP, based on the positional deviation amount detected by the positional deviation detecting unit 48. This notification information is input to the display control unit 47. The display control unit 47 generates an arrow 50 indicating the direction included in the notification information, for example, Figure 10 As shown, the arrow 50 is combined with the superimposed image TP and displayed on the display 30 .

[0106] The positional deviation detection unit 48 and notification information generation unit 49 perform processing each time a frame of the moving image MP is input. Therefore, the direction and size of the arrow 50 displayed on the display 30 change as the subject H moves. For example, the size of the arrow 50 decreases as the amount of positional deviation detected by the positional deviation detection unit 48 decreases. The technician RG can issue instructions to the subject H using sound or other means based on the arrow 50 displayed on the display 30, guiding the subject H in the direction of the decreasing arrow 50. This allows the subject H to be positioned relative to the position at the time of loss of photography, as shown in the still image SP. Therefore, even if the subject H has moved significantly from the time of loss of photography, the technician RG can still position the subject H relative to the position at the time of loss of photography and make fine adjustments to the subject H's position based on this position. Furthermore, a microphone can be provided in the operation room and a speaker can be provided in the photography room to allow the technician RG to issue instructions to the subject H. This allows the technician RG to easily issue positioning instructions to the subject H in the photography room from the operation room.

[0107] When the positional deviation detecting unit 48 is capable of detecting the positional deviation caused by rotation or slewing, the notification information generating unit 49 may generate notification information indicating the direction of rotation or slewing. Figure 11 This shows an example in which an arrow 51 indicating that the knee of the subject H should be internally rotated is displayed on the superimposed image TP in order to move the position of the subject H back to the position at the time of the loss of imaging. In this case, internal rotation is an action of the subject H turning the knee inward.

[0108] Next, refer to Figure 12 The flowchart shown and Figures 13 to 17 The function of the photography assisting device of the above structure is explained. First, before performing photography, the technician RG confirms the content of the photography order 37 through the display 30, and sets the irradiation conditions using the input device 31 and the touch panel 12A. Next, the technician RG positions the X-ray source 11, the electronic cassette 13 and the subject H according to the photography technique included in the photography order 37. Here, the photography technique is set to "knee / bent posture / side". The technician RG bends one leg of the subject H to position the subject H in such a way that the side of the knee faces the X-ray incident surface 13A of the electronic cassette 13 and the knee is located in the center of the irradiation field RF (refer to Figure 1 ).

[0109] The still image photography instruction unit 41 determines whether it has received an X-ray irradiation start signal ES from the control unit 12C of the X-ray source control device 12 (step S10). The X-ray irradiation start signal ES is generated by the control unit 12C of the X-ray source control device 12 when the technician RG presses the irradiation switch 16 after positioning the subject H. The X-ray irradiation start signal ES generated by the control unit 12C is supplied to the voltage generator 12B and the console 14. The voltage generator 12B irradiates the subject H with X-rays from the X-ray source 11 in response to the X-ray irradiation start signal ES. The electronic cassette 13 detects an X-ray image XP of the subject H based on the X-rays that have passed through the subject H.

[0110] Upon receiving the X-ray irradiation start signal ES (step S10: YES), the still image photography instruction unit 41 instructs the optical camera 15 to perform still image photography (step S11). The still image acquisition unit 42 acquires the still image SP generated by the still image photography performed by the optical camera 15 (step S12). Furthermore, the console 14 acquires the X-ray image XP detected by the electronic cassette 13 (step S13).

[0111] Next, the correlating unit 43 correlates the acquired X-ray image XP and the still image SP and stores them in the storage device 34 (step S14). The display controller 47 displays the X-ray image XP stored in the storage device 34 on the display 30 (step S15). Figure 13 FIG. 4 shows an example of a screen of the display 30 displaying the X-ray image XP. Figure 13 As shown, an X-ray image XP is displayed in the image display area 30A of the display 30 .

[0112] Furthermore, display 30 displays a first operation button 31A for reshooting, a second operation button 31B for inputting a reason for loss of photography, and a third operation button 31C for ending the operation. First operation button 31A, second operation button 31B, and third operation button 31C constitute input device 31 and are operated via a touch panel formed on the screen of display 30.

[0113] When the engineer RG confirms the X-ray image XP displayed in the image display area 30A and determines that it is good, he or she presses the third operation button 31C to terminate the process related to X-ray imaging.

[0114] On the other hand, when the technician RG confirms the X-ray image XP displayed in the image display area 30A and determines that there is an imaging loss, he or she can use the second operation button 31B to perform the operation. Figure 14The keyboard 31K shown is used to input the reason for loss of photography. The input reason for loss of photography 52 is displayed on the image display area 30A by the display control unit 47. The keyboard 31K is, for example, a virtual keyboard, and is displayed on the screen of the display 30 in an operable manner via a touch panel. Figure 13 and Figure 14 The X-ray image XP shown is an example in which bones of the joint overlap on the X-ray optical path due to external rotation of the knee, thereby reducing the visibility of the joint cavity JC.

[0115] Figure 15 The figure schematically shows a state in which the visibility of the joint cavity JC decreases in the X-ray image XP due to the rotation of the knee. Figure 16 The diagram schematically illustrates the reduced visibility of the joint cavity JC in the X-ray image XP due to knee translation. The X-rays irradiating the subject H are radially diverging beams from the focal point of the X-ray source 11. Therefore, positional deviations such as rotation, rotation, and translation of the subject H cause changes in the angle of incidence of the X-rays relative to the subject H, reducing visibility of the joint cavity JC. Furthermore, the joint cavity JC is actually narrow, and knee translational deviations involve a complex process of rotation, rotation, and translation. Therefore, even slight positional deviations can reduce visibility of the joint cavity JC.

[0116] When reshooting, the technician RG presses the first operation button 31A (refer to Figure 13 ). When the first operation button 31A is pressed, the input device 31 generates a reshooting preparation start signal RS and transmits it to the moving image shooting instruction unit 44.

[0117] return Figure 12 After step S15, it is determined whether the technician RG has performed an end operation by pressing the third operation button 31C (step S16). If it is determined that an end operation has been performed (step S16: Yes), the process ends.

[0118] On the other hand, if the end operation has not been performed (step S16: No), the moving image shooting instruction unit 44 determines whether a reshooting preparation start signal RS has been received from the input device 31 (step S17). If the moving image shooting instruction unit 44 has received the reshooting preparation start signal RS (step S17: Yes), it transmits a moving image shooting start signal to the optical camera 15 (step S18). The moving image acquisition unit 45 acquires the moving image MP generated by the moving image shooting by the optical camera 15 frame by frame (step S19).

[0119] The superimposition processing unit 46 acquires the still image SP stored in the storage device 34 and superimposes the still image SP on the frame of the moving image MP acquired by the moving image acquisition unit 45, thereby generating a superimposed image TP (step S20). The positional offset detection unit 48 acquires the still image SP stored in the storage device 34 and detects the positional offset of the subject H between the frame of the moving image MP acquired by the moving image acquisition unit 45 and the still image SP (step S21). Based on the positional offset detected by the positional offset detection unit 48, the notification information generation unit 49 generates notification information indicating the direction (vector) in which the current position of the subject H should be moved toward the position of the subject H at the time of the loss of image capture (step S22).

[0120] The display control unit 47 generates an arrow (eg, Figure 10 The arrow 50 shown is synthesized on the superimposed image TP and displayed on the display 30 (step S23). Thereafter, similarly to step S10, the still image photography instruction unit 41 determines whether an X-ray irradiation start signal ES has been received from the control unit 12C (step S24).

[0121] If the still image imaging instruction unit 41 does not receive the X-ray irradiation start signal ES (step S24: No), the process returns to step S19, and the moving image acquisition unit 45 acquires the next frame of the moving image MP. The processes of steps S19 to S24 are repeated until the X-ray irradiation start signal ES is received. As a result, a superimposed image TP, in which the still image SP is superimposed on the moving image MP, is displayed in real time on the display 30.

[0122] Figure 17 FIG. 4 shows an example of a screen of the display 30 displaying the superimposed image TP. Figure 17 As shown, an overlay image TP is displayed in the image display area 30A of the display 30. An arrow 50 and a reason for loss of photography 52 are displayed in combination with the overlay image TP. The technician RG can use the overlay image TP to confirm whether the position of the subject H has moved since the time of loss of photography. If the subject H has moved, the technician RG provides instructions to the subject H using the arrow 50 or other means, such as sound, thereby temporarily resetting the subject H's current position (the position shown in the moving image MP) to the position at the time of loss of photography (the position shown in the still image SP).

[0123] After the technician RG has provisionally determined the position of the subject H at the time of the imaging loss, he or she can refer to the imaging loss reason 52 and make fine adjustments to the position of the subject H to avoid imaging loss during re-radiation. Furthermore, the display 30 can display the X-ray image XP in addition to the overlay image TP. The technician RG can refer to the imaging loss reason 52 and the X-ray image XP to make fine adjustments to the position of the subject H. After completing the fine adjustments to the position of the subject H, the technician RG presses the irradiation switch 16 to execute re-radiation.

[0124] return Figure 12 If the technician RG presses the irradiation switch 16 and the still image photography instruction unit 41 receives the X-ray irradiation start signal ES (step S24: Yes), the still image photography instruction unit 41 instructs the optical camera 15 to execute still image photography (step S11). Upon receiving the still image photography instruction, the optical camera 15 terminates the moving image photography and begins still image photography. The same process is then repeated.

[0125] Below, reference Figure 18 and Figure 19 The effect of the photography assist device of the above structure will be explained. When performing X-ray photography, sometimes, depending on the imaging part, even if the technician RG believes that the subject H has been accurately positioned, it is actually not accurately positioned, resulting in photography loss. For example, when diagnosing a knee joint, the joint cavity JC needs to be clearly depicted in the X-ray image XP. However, X-rays are beams that diverge radially from the focus of the X-ray source 11. Therefore, due to slight positional deviations of the joint, the incident angle of the X-rays changes, resulting in unclear depiction of the joint cavity JC. If the depiction of the joint cavity JC is unclear, it becomes a photography loss, and re-photography is required.

[0126] Thus, when reshooting is necessary due to lost shooting, the technician RG needs to reposition the subject H. When adjusting a slight positional deviation of the subject H during reshooting, usually fine adjustments can be made based on the position of the subject H at the time of lost shooting.

[0127] However, if Figure 18As shown, with conventional techniques, if the subject H has moved significantly since the time of imaging loss, the technician RG cannot accurately determine the position of the subject H at the time of imaging loss, making it impossible to perform fine adjustments. If the technician RG repositions the subject H from the beginning, there is a high probability that the subject H will be repositioned in the same position, resulting in imaging loss again. Thus, with conventional techniques, even if the subject H is positioned using an optical camera or the like before X-ray imaging, if imaging loss occurs, the technician RG cannot determine the position of the subject H at the time of imaging loss, resulting in a high probability of imaging loss again, leading to repeated re-radiation.

[0128] In contrast, Figure 19 As shown, the technique of the present invention acquires an optical image (still image SP) showing the subject H in conjunction with X-ray imaging. Therefore, even if the subject H has moved significantly since the time of imaging loss, the technician RG can easily grasp the position of the subject H at the time of imaging loss. Therefore, after positioning the subject H at the position at the time of imaging loss, the technician RG can fine-tune the position of the subject H from that position based on the reason for the imaging loss. After fine-tuning the position of the subject H, re-radiation is performed, thereby obtaining a good X-ray image XP. Thus, the technique of the present invention can reduce the need for repeated re-radiation. Consequently, unnecessary radiation exposure to the subject H can be reduced, shortening the examination time.

[0129] Furthermore, the technique of the present invention displays in real time a superimposed image TP obtained by superimposing an optical image (still image SP) acquired in conjunction with X-ray imaging and a current optical image (moving image MP) of the subject H. Even if the subject H has moved significantly since the time of imaging loss, the technician RG can more easily grasp the position of the subject H at the time of imaging loss based on the still image SP in the superimposed image TP.

[0130] [Modification of the first embodiment]

[0131] Next, various variations of the first embodiment will be described. In the first embodiment, the notification unit that transmits the notification information generated by the notification information generating unit 49 is provided as the display 30, and an arrow is used to indicate the direction in which the current position of the subject H should move toward the position of the subject H at the time of the loss of the image. This notification information may be in the form of characters or information incorporating characters into the arrow. Furthermore, a speaker may be used as the notification unit to provide audible notification of the notification information.

[0132] Furthermore, the notification information generating unit 49 may generate a warning message for issuing a warning to the technician RG when the position deviation amount detected by the position deviation detecting unit 48 is greater than a predetermined value. The notification information generating unit 49 is executed in parallel with the notification information generating process (step S22) described in the above embodiment. Figure 20 As shown in the following example. Figure 20 As shown, the notification information generating unit 49 obtains the positional deviation amount (e.g., the magnitude of a vector indicating a direction) from the positional deviation detecting unit 48 (step S30), and determines whether the obtained positional deviation amount is greater than or equal to a predetermined value (step S31). If the positional deviation amount is greater than or equal to the predetermined value (step S31: Yes), the notification information generating unit 49 generates warning information (step S32) and outputs the generated warning information to the speaker serving as the notification unit (step S33).

[0133] A warning sound or voice, etc., indicating that the positional deviation exceeds a predetermined value, is output to the technician RG from the speaker. This allows the technician RG to recognize that the subject H has moved, even without viewing the screen of the display 30. The notification unit for delivering the warning information is not limited to a speaker; any notification unit that stimulates the technician RG's senses (hearing, vision, etc.) may be used. Furthermore, the display 30 may serve as the notification unit, displaying a warning message on the screen.

[0134] Furthermore, in the first embodiment, as Figure 14 As shown, the technician RG can input the radiographic loss reason using a keyboard 31K or the like. However, the CPU 32 may also automatically determine the radiographic loss reason based on the X-ray image XP using a machine learning method utilizing a neural network. The neural network learns using data that associates X-ray images XP with radiographic loss and the radiographic loss reason as training data. This allows the neural network to determine the radiographic loss reason, such as external rotation, internal rotation, and the angle between them, for a new X-ray image XP with radiographic loss.

[0135] Furthermore, in the first embodiment, as Figure 17 As shown, the position of the subject H is moved by the technician RG to the position at the time of the imaging loss according to the arrow 50 displayed on the superimposed image TP. Alternatively, the position of the subject H may be moved without changing the position of the subject H but instead the X-ray irradiation field RF may be moved to move the relative position of the subject H with respect to the irradiation field RF to the position at the time of the imaging loss.

[0136] In this modification, if Figure 21As shown, an irradiation field movement control unit 60 for controlling the movement of the irradiation field RF is added to the CPU 32 of the console 14. The irradiation field movement control unit 60 controls the moving mechanism 19 for moving the X-ray source 11 via the control unit 12C of the ray source control device 12 based on the positional deviation amount detected by the positional deviation detection unit 48. The moving mechanism 19 is composed of the aforementioned suspension holding mechanism 17 and the horizontal moving mechanism 18. Figure 22 As shown, the irradiation field movement control unit 60 moves the irradiation field RF in a direction in which the positional deviation amount detected by the positional deviation detection unit 48 decreases, thereby moving the relative position of the subject H with respect to the irradiation field RF to the position at the time of imaging loss.

[0137] In addition, Figure 22 In the example shown, the electronic cassette 13 is fixed. However, if the electronic cassette 13 is configured to be movable in conjunction with the movement of the X-ray source 11 , the electronic cassette 13 can be moved along with the movement of the irradiation field RF.

[0138] [Second embodiment]

[0139] Next, a second embodiment of the present invention will be described. Figure 23 In the embodiment, the X-ray imaging system 10A according to the second embodiment includes a projector 70 in addition to the configuration of the X-ray imaging system 10 according to the first embodiment. In this embodiment, the CPU 32, the optical camera 15, and the projector 70 constitute an imaging support device.

[0140] The projector 70 is attached to the outer periphery of the X-ray source 11. The projector 70 is, for example, a small laser projector, and is arranged so as to project an image toward the X-ray incident surface 13A of the electronic cassette 13.

[0141] In this embodiment, if Figure 24 As shown, a projection image generating unit 71 for generating a projection image to be supplied to the projector 70 is additionally provided within the CPU 32 of the console 14. The projection image generating unit 71 generates a projection image by acquiring a still image SP captured by the optical camera 15 and associated with the X-ray image XP by the association unit 43 and stored in the storage device 34.

[0142] The projection image generator 71 supplies the generated projection image to the projector 70, causing the projector 70 to project the projection image toward the electronic cassette 13. The projection image generator 71 performs projection while the subject H is positioned between the X-ray source 11 and the electronic cassette 13, during preparation for re-radiation, when the superimposed image TP is displayed on the display 30. The remaining configuration of the X-ray imaging system 10A is the same as that of the X-ray imaging system 10 according to the first embodiment.

[0143] Figure 25 The projected image 72 projected by the projector 70 onto the electronic cassette 13 is shown as an example. Figure 25 In the figure, the projected image 72 is an image of the subject H at the time of the loss of photography, and a portion of the image is projected onto the surface of the subject H. In this embodiment, when preparing for re-photography, the technician RG adjusts the position of the subject H so that the subject H overlaps with the projected image 72, thereby moving the position of the subject H back to the position at the time of the loss of photography.

[0144] [Third embodiment]

[0145] Next, the third embodiment of the present invention will be described. Figure 26 In the third embodiment, the X-ray imaging system 10B includes, in addition to the configuration of the X-ray imaging system 10 of the first embodiment, a remote controller 80 for causing the optical camera 15 to perform still image imaging. In this embodiment, the CPU 32, the optical camera 15, and the remote controller 80 constitute an imaging assist device.

[0146] The remote controller 80 is connected to the console 14 via a wired or wireless connection. The technician RG can send an imaging instruction signal IS from the imaging room to the console 14 by operating the remote controller 80. Before performing X-ray imaging, the technician RG operates the remote controller 80 while positioning the subject H, thereby instructing still image imaging.

[0147] The console 14 receives the photographing instruction signal IS from the remote controller 80 via the communication unit 35. Alternatively, the optical camera 15 may include a receiving unit for the photographing instruction signal IS transmitted from the remote controller 80.

[0148] In this embodiment, the still image photography instruction unit 41 receives an X-ray irradiation start signal ES from the control unit 12C and an imaging instruction signal IS from the remote control 80. Upon receiving the imaging instruction signal IS, the still image photography instruction unit 41 instructs the optical camera 15 to perform still image photography. Furthermore, the still image acquisition unit 42 acquires still images SP captured by the optical camera 15 in conjunction with X-ray photography, as well as still images SPO captured in response to an instruction from the remote control 80. Furthermore, the association unit 43 associates the still image SP0 acquired during positioning of the subject H with the X-ray image XP and the still image SP acquired during the subsequent X-ray photography, and stores the associated images in the storage device 34.

[0149] In this embodiment, an image selection unit 81 is additionally provided within the CPU 32. The image selection unit 81 selects an image to be supplied to the superimposition processing unit 46 and the positional shift detection unit 48 based on an operation signal input from the input device 31. Specifically, the image selection unit 81 selects, based on the operation signal, which of the still image SP0 and the still image SP associated and stored in the storage device 34 to supply to the superimposition processing unit 46 and the positional shift detection unit 48.

[0150] The superimposition processing unit 46 acquires the image (still image SP0 or still image SP) selected by the image selection unit 81 and superimposes the acquired image on each frame of the moving image MP to generate a superimposed image TP. The positional offset detection unit 48 acquires the image (still image SP0 or still image SP) selected by the image selection unit 81 and detects the amount of positional offset between the acquired image and the subject H in each frame of the moving image MP. The remaining configuration of the X-ray imaging system 10B is the same as that of the X-ray imaging system 10 according to the first embodiment.

[0151] Next, refer to Figure 28 and Figure 29 The flowchart shown in FIG. 1 illustrates the operation of the imaging assisting device according to the third embodiment. Before performing X-ray imaging, the technician RG positions the subject H relative to the X-ray source 11 and the electronic cassette 13 (see FIG. 2 ). Figure 26 The technician RG operates the remote controller 80 while positioning the subject H at a desired position, thereby instructing the optical camera 15 to perform still image photography.

[0152] The still image shooting instruction unit 41 determines whether it has received a shooting instruction signal IS from the remote controller 80 (step S40). If the still image shooting instruction signal IS has been received (step S40: Yes), the still image shooting instruction unit 41 instructs the optical camera 15 to shoot a still image (step S41). The still image acquisition unit 42 acquires a still image SP0 generated by the still image shooting performed by the optical camera 15 (step S12). The still image SP0 acquired by the still image acquisition unit 42 is stored in the storage device 34 via the association unit 43 (step S43).

[0153] Afterward, the technician RG operates the input device 31 to begin preparations for X-ray imaging. The moving image imaging instruction unit 44 determines whether a radiography preparation start signal has been received from the input device 31 (step S44). If so, it transmits a moving image imaging start signal to the optical camera 15 (step S45). The moving image acquisition unit 45 acquires the moving images MP generated by the optical camera 15 through moving image imaging, frame by frame (step S46).

[0154] The superimposition processing unit 46 acquires an image stored in the storage device 34. Here, the still image SP0 is selected by the image selection unit 81. The superimposition processing unit 46 acquires the still image SP0 via the image selection unit 81 and performs processing to superimpose the still image SP0 on the frame of the moving image MP acquired by the moving image acquisition unit 45, thereby generating a superimposed image TP (step S47).

[0155] The positional deviation detecting unit 48 acquires the still image SP0 stored in the storage device 34 via the image selecting unit 81, and detects the amount of positional deviation between the frame of the moving image MP acquired by the moving image acquiring unit 45 and the subject H in the still image SP0 (step S48). Based on the amount of positional deviation detected by the positional deviation detecting unit 48, the notification information generating unit 49 generates notification information indicating the direction (vector) in which the current position of the subject H should be moved toward the position of the subject H at the time of initial positioning (step S49).

[0156] The display control unit 47 generates an arrow indicating the direction included in the notification information, and displays the arrow on the display 30 in a state where the arrow is combined with the superimposed image TP (step S50). Figure 12 Similarly to step S10 shown, the still image capturing instruction unit 41 determines whether or not an X-ray irradiation start signal ES has been received from the control unit 12C (step S51 ).

[0157] If the still image imaging instruction unit 41 does not receive the X-ray irradiation start signal ES (step S51: No), the process returns to step S46, and the moving image acquisition unit 45 acquires the next frame of the moving image MP. The processes of steps S46 to S51 are repeated until the X-ray irradiation start signal ES is received. As a result, a superimposed image TP, in which the still image SP0 is superimposed on the moving image MP, is displayed in real time on the display 30.

[0158] The superimposed image TP displayed on the display 30 is the same as that in the first embodiment. Figure 17 The technician RG can confirm whether the position of the subject H has moved from the initial positioning based on the superimposed image TP. If the subject H has moved, the technician RG instructs the subject H using an arrow or the like displayed on the superimposed image TP, or by voice or the like, thereby causing the subject H to move from its current position (the position shown in the moving image MP) to its position at the time of positioning (the position shown in the still image SP0).

[0159] Then, when the technician RG presses the irradiation switch 16 and the still image photography instruction unit 41 receives the X-ray irradiation start signal ES (step S51: Yes), the still image photography instruction unit 41 instructs the optical camera 15 to perform still image photography (step S52). The processing of steps S52 to S65 is the same as that in the first embodiment. Figure 12 The processes of steps S11 to S24 are identical, and thus their description is omitted. In this embodiment, the X-ray image XP and the still image SP captured in conjunction with the X-ray imaging are associated with the still image SP0 and stored in the storage device 34 .

[0160] In this embodiment, an image (still image SP0 or still image SP) to be superimposed on the moving image MP can be selected in preparation for reshooting. Figure 30 As shown, the display 30 screen displays, in addition to the first to third operation buttons 31A to 31C, a fourth operation button 31D for switching images. By operating the fourth operation button 31D, the technician RG can switch the image superimposed on the moving image MP between the still image SP0 acquired during initial positioning and the still image SP acquired during image loss. This allows the technician RG to retake the image by moving the subject H back to the position of the subject H during initial positioning.

[0161] And, as Figure 31 As shown, it is also preferable to display the still image SP0 acquired during the initial positioning and the still image SP acquired during the imaging loss in an overlapping manner. This allows the technician RG to determine whether the imaging loss occurred due to the subject H moving from the initial positioning or whether the imaging loss occurred even though the subject H did not move from the initial positioning.

[0162] In addition, the first embodiment can be modified as appropriate unless there is any contradiction. Figure 12 The flowchart shown and the third embodiment Figure 28 and Figure 29 The order of the processing included in the flowchart shown is as follows. It is natural that the acquisition of still images and the acquisition of X-ray images, the superposition processing, the positional shift detection, and other processing can be repeated temporally.

[0163] The optical camera 15 may be mounted on a wall or ceiling of the imaging room, other than the X-ray source 11, as long as it can capture the subject H within the irradiation field RF. Furthermore, the optical camera 15 is not limited to a camera that captures visible light; any camera that captures images optically may be used. For example, the optical camera 15 may be an infrared camera that captures images using infrared light.

[0164] The projector 70 may be installed at a location other than the X-ray source 11 , such as a wall or ceiling of the imaging room, as long as it can project an image of the irradiation field RF.

[0165] The above embodiments have been described by taking the X-ray imaging system installed in an imaging room as an example, but the X-ray imaging system may also be a system using a so-called mobile medical cart.

[0166] Furthermore, the technology of the present invention is not limited to X-rays, but can also be applied to a system that uses other radiation such as gamma rays to image a subject.

[0167] In each of the above-mentioned embodiments, the hardware structure of the processing units (processing units) that perform various processes, such as the still image photography instruction unit 41, the still image acquisition unit 42, the association establishment unit 43, the dynamic image photography instruction unit 44, the dynamic image acquisition unit 45, the superposition processing unit 46, the display control unit 47, the position shift detection unit 48, the notification information generation unit 49, the irradiation field movement control unit 60, the projection image generation unit 71, and the image selection unit 81, is the various processors shown below.

[0168] Various processors include CPUs, programmable logic devices (PLDs), and dedicated circuits. As is well known, a CPU is a general-purpose processor that executes software (programs) to function as a variety of processing units. A PLD is a processor whose circuit structure can be modified after manufacturing, such as an FPGA (Field Programmable Gate Array). A dedicated circuit is a processor with a circuit structure specifically designed to perform specific processing, such as an ASIC (Application Specific Integrated Circuit).

[0169] A single processing unit may be composed of one of these various processors, or a combination of two or more processors of the same or different types (e.g., a combination of multiple FPGAs or a CPU and an FPGA). Furthermore, a single processor may constitute multiple processing units.

[0170] As examples of multiple processing units being composed of a single processor, there is a method in which a single processor is composed of a combination of one or more CPUs and software, with the processor functioning as multiple processing units. A second method is a method using a processor, such as a system-on-chip (SoC), that implements the functions of an entire system including multiple processing units on a single IC chip. In this manner, the various processing units are constructed as hardware using one or more of the aforementioned processors.

[0171] Furthermore, as the hardware configuration of these various processors, more specifically, a circuit (circuitry) combining circuit elements such as semiconductor elements can be used.

[0172] The present invention is not limited to the above-described embodiments, and various configurations can be employed without departing from the spirit of the present invention. Furthermore, the present invention relates not only to a program but also to a storage medium that stores the program non-transitorily.

Claims

1. A radiographic assisting device for use in a radiographic apparatus comprising a radiation source and a radiographic image detector for detecting a radiographic image of a subject based on radiation irradiated from the radiation source and transmitted through the subject, the radiographic assisting device comprising: an optical camera that optically photographs an area including an irradiation field of the radiation irradiated from the radiation source to the subject; and At least 1 processor, The processor performs the following processing: Acquiring an optical image showing the subject within the area as a first optical image by performing imaging by the optical camera and radiography by the radiographic device in conjunction with each other; storing the radiographic image acquired by the radiography and the first optical image in association with each other in a storage unit; acquiring an optical image showing the subject within the area as a second optical image by performing imaging with the optical camera after performing the radiography; and A superimposed image in which the first optical image is superimposed on the second optical image and the radiation image are displayed on a display unit.

2. The photography assisting device according to claim 1, wherein: The first optical image is a still image and the second optical image is a dynamic image, The processor overlaps the second optical image with the first optical image and displays the overlapped images on the display unit in real time.

3. The photography assisting device according to claim 1, wherein: The processor performs the following processing: detecting a positional offset of a subject in the first optical image and the second optical image by image processing; and Information on the positional deviation amount is supplied to a notification section.

4. The photography assisting device according to claim 3, wherein: The notification unit is the display unit, The processor displays on the display unit a direction for moving the position of the subject toward the position indicated by the first optical image based on the positional offset.

5. The photography assisting device according to claim 3, wherein: The processor causes the notification unit to output a warning when the positional deviation amount is equal to or greater than a predetermined value.

6. The photography assisting device according to claim 3, wherein: The radiographic apparatus includes a moving mechanism for moving the radiation exposure field. The processor controls the moving mechanism to move the irradiation field in a direction in which the positional deviation amount is reduced.

7. The photography assisting device according to claim 1, wherein: The optical camera performs photography based on visible light or infrared light.

8. The photography assisting device according to any one of claims 1 to 5, wherein: The imaging assisting device includes a projector that projects the first optical image onto the radiation image detector.

9. A method for operating a photography assisting device, the photography assisting device being used in a radiographic apparatus, the radiographic apparatus comprising a radiation source and a radiation image detector for detecting a radiographic image of a subject based on radiation irradiated from the radiation source and transmitted through the subject, the photography assisting device including an optical camera for optically photographing an area including an irradiation field of the radiation irradiated from the radiation source to the subject, the method comprising the following steps: Acquiring an optical image showing the subject within the area as a first optical image by performing imaging by the optical camera and radiography by the radiographic device in conjunction with each other; storing the radiographic image acquired by the radiography and the first optical image in association with each other in a storage unit; acquiring an optical image showing the subject within the area as a second optical image by performing imaging with the optical camera after performing the radiography; and A superimposed image in which the first optical image is superimposed on the second optical image and the radiation image are displayed on a display unit.

10. A computer-readable storage medium storing an operating program for operating a photography assisting device, the photography assisting device being used in a radiographic apparatus, the radiographic apparatus comprising a radiation source and a radiation image detector for detecting a radiographic image of a subject based on radiation irradiated from the radiation source and transmitted through the subject, the photography assisting device comprising an optical camera for optically photographing an area including an irradiation field of the radiation irradiated from the radiation source to the subject, and at least one processor, the operating program causing the processor to perform the following operations: Acquiring an optical image showing the subject within the area as a first optical image by performing imaging by the optical camera and radiography by the radiographic device in conjunction with each other; storing the radiographic image acquired by the radiography and the first optical image in association with each other in a storage unit; acquiring an optical image showing the subject within the area as a second optical image by performing imaging with the optical camera after performing the radiography; and A superimposed image in which the first optical image is superimposed on the second optical image and the radiation image are displayed on a display unit.

Images