Photography auxiliary device, working method thereof and storage medium

Abstract

The present application relates to a photography assisting apparatus for a radiographic apparatus having a radiation source and a radiation image detector that detects a radiation image of an object based on radiation that is radiated from the radiation source and transmitted through the object, the photography assisting apparatus including: an optical camera that outputs an optical image by optically photographing a region including a radiation field in which radiation is radiated from the radiation source to the object; and at least one processor that associates the optical image acquired by the optical camera with the radiation image based on a timing signal transmitted from the radiation image detector.

Description

Technical Field

[0001] The present invention relates to a photographic aid device, its operating method, and a storage medium. Background Technology

[0002] In radiographic systems used in the medical field, as preparation for radiography, after the radiographic site of the subject is positioned by a radiographer or physician (hereinafter referred to as technicians, etc.), radiographic imaging is performed according to the technicians' instructions. However, after the radiographic site is positioned relative to the radiation field but before radiographic imaging, the position of the radiographic site may shift due to movement of the subject, sometimes making it impossible to obtain an image of the desired radiographic site. This situation, where the desired radiographic image is not obtained through radiographic imaging, i.e., radiographic imaging failure, is called "radiographic loss." When radiographic loss occurs, re-enhancing radiography is performed. Furthermore, there are cases where technicians, etc., mistakenly identify radiographic images that do not require re-enhancing as radiographic loss, resulting in unnecessary re-enhancing. Re-enhancing is time-consuming and labor-intensive, and increases the radiation dose to the subject; therefore, it is preferable to minimize re-enhancing.

[0003] Related to this re-photography, Japanese Patent Application Publication No. 2008-206740 discloses a radiographic system equipped with an optical camera that captures a light image (hereinafter also referred to as an optical image) of the exposed area of ​​a subject irradiated with radiation during radiation generation based on a radiation-generating unit. In the radiographic system described in Japanese Patent Application Publication No. 2008-206740, an optical image captured simultaneously with a previous radiographic image of the subject is stored in advance, and the offset between the position of the subject in the previous optical image and the position of the subject in the current optical image is calculated. Therefore, the position of the subject when a new radiographic image of the subject is captured can be aligned using the image content of the optical image.

[0004] Furthermore, Japanese Patent Application Publication No. 6-217973 discloses an X-ray imaging apparatus equipped with an optical camera that captures a surface image (hereinafter also referred to as an optical image) of a subject within an X-ray irradiation field. In the X-ray imaging apparatus described in Japanese Patent Application Publication No. 6-217973, during X-ray imaging, in response to an exposure signal from an X-ray control unit, a timing control unit controls the storage timing of the X-ray image and the surface image, thereby establishing a correlation between and storing X-ray images and surface images related to the same object area. Summary of the Invention

[0005] The technical problem to be solved by the invention

[0006] There are also slight positional shifts, meaning that even if technicians believe the location is accurate based on the photographic site, it may not actually be accurately positioned, resulting in photographic loss. For example, when diagnosing the condition of a knee joint based on a radiographic image with the knee joint as the photographic site, the joint cavity (the space between bones) needs to be clearly depicted in the radiographic image. However, radiation is a beam of lines radiating from the focal point of the radiation source. Therefore, due to slight positional shifts in the joint, the angle of incidence of the radiation changes, resulting in an unclear depiction of the joint cavity. An unclear depiction of the joint cavity constitutes photographic loss and requires re-photographing.

[0007] Furthermore, even when radiographic images that should be deemed necessary to be re-photographed are obtained, there are often cases where, depending on the subject, re-photographing would not improve the situation, and therefore, re-photographing should not be deemed necessary. For this determination, it is desirable to refer to both the radiographic and optical images generated at the same time during the subject's last examination.

[0008] According to the technology described in Japanese Patent Application Publication No. 2008-206740 and Japanese Patent Application Publication No. Hei 6-217973, when re-photographing, technicians can refer to optical images previously taken simultaneously with radiographic images to reposition the subject. For accurate positioning of the subject, the optical image must be taken at the same time as the radiographic image, which results in photographic loss. In particular, as mentioned above, when the knee joint is used as the photographic site, slight positional shifts of the subject can cause photographic loss; therefore, it is preferable to take both the optical and radiographic images at the same time whenever possible.

[0009] Japanese Patent Application Publication No. 2008-206740 describes storing an optical image captured simultaneously with a radiographic image of the subject, but does not specify how the radiographic and optical images are acquired simultaneously.

[0010] Japanese Patent Application Publication No. 6-217973 describes a method for controlling the timing of X-ray image and surface image storage in response to an exposure signal from an X-ray control unit. The exposure signal is output by pressing an exposure switch. Therefore, a time delay occurs from the time the exposure signal is output from the X-ray control unit until X-rays are actually emitted from the X-ray tube. Furthermore, Japanese Patent Application Publication No. 6-217973 uses X-ray film as a radiation detector. When an electronic cassette is used instead of X-ray film, a further time delay sometimes occurs from the time the exposure switch is pressed until radiation detection preparation is completed at the electronic cassette side.

[0011] Therefore, as described in Japanese Patent Application Publication No. 6-217973, when an optical image is captured in response to an exposure signal, a time lag occurs from the output of the exposure signal to the detection of radiation by the radiation detector, which may cause a deviation in the acquisition time of the radiation image and the optical image.

[0012] The purpose of this disclosure is to provide a photographic aid device, its working method, and its working procedure that can reduce the deviation in the acquisition time of radiographic and optical images.

[0013] means for solving technical problems

[0014] To achieve the above objectives, the present disclosure provides a photographic aid device for use in a radiographic device, the radiographic device having a radiation source and a radiation image detector for detecting a radiation image of a subject based on radiation irradiated from and transmitted through the radiation source. The photographic aid device comprises: an optical camera that outputs an optical image by performing optical photography on an area including an irradiation field containing radiation irradiated from the radiation source onto the subject; and at least one processor that associates the optical image acquired by the optical camera with the radiation image based on a timing signal sent from the radiation image detector side.

[0015] The timing signal is preferably an irradiation start detection signal output from a radiation image detector with radiation irradiation start detection function.

[0016] The timing signal is preferably a radiation detection signal output from an automatic exposure controller that is separate from the radiation image detector.

[0017] The timing signal is preferably a preparation completion signal output when the radiation image detector has completed the radiation detection preparation.

[0018] Preferably, the optical camera is a dynamic image photography device that acquires optical images frame by frame and outputs a dynamic image composed of multiple acquired frames. The processor acquires one frame from the dynamic image according to a timing signal sent from the radiation image detector side and establishes a correlation between the extracted frame and the radiation image.

[0019] The processor prefers to discard frames other than those extracted.

[0020] The processor preferably associates patient information with the established optical and radiographic images and outputs them externally.

[0021] The present disclosure discloses a method for operating a photographic aid device for use in a radiographic device. The radiographic device includes a radiation source and a radiation image detector for detecting a radiation image of a subject based on radiation irradiated from and transmitted through the radiation source. The photographic aid device also includes an optical camera that outputs an optical image by performing optical photography on an area including an irradiation field containing radiation irradiated from the radiation source onto the subject. In the method of operating the photographic aid device, an optical image and a radiation image acquired by the optical camera are correlated based on a timing signal sent from the radiation image detector side.

[0022] The operating procedure of this disclosure enables a photographic aid device for use in a radiographic device having a radiation source and a radiation image detector for detecting a radiation image of a subject based on radiation irradiated from and transmitted through the radiation source. The photographic aid device includes an optical camera that outputs an optical image by optically photographing an area including an irradiation field containing radiation irradiated from the radiation source onto the subject, and at least one processor. The operating procedure causes the processor to perform the following processing: establishing a correlation between the optical image acquired by the optical camera and the radiation image based on a timing signal sent from the radiation image detector side.

[0023] Invention Effects

[0024] According to the technology disclosed herein, a photographic aid device, its working method, and its working procedure can be provided to reduce the deviation in the acquisition time of radiographic and optical images. Attached Figure Description

[0025] Figure 1 This is a diagram showing the structure of an X-ray imaging system.

[0026] Figure 2 This is a 3D view of the electronic dark box.

[0027] Figure 3 This is a diagram showing the structure of the photodetector substrate.

[0028] Figure 4 This is a graph illustrating the detection at the start of irradiation.

[0029] Figure 5 It is a block diagram representing the structure of the console.

[0030] Figure 6 This is an example of a photography order.

[0031] Figure 7 This is a diagram illustrating a condition table.

[0032] Figure 8This is a diagram illustrating the established association between X-ray images and still images.

[0033] Figure 9 It is a block diagram representing the various functional units that make up the CPU.

[0034] Figure 10 This is a diagram illustrating the overlapping process.

[0035] Figure 11 This is an example of a control panel display after X-ray imaging.

[0036] Figure 12 This is an example of a control panel display during the preparation for a reshoot.

[0037] Figure 13 It is a flowchart illustrating the CPU's processing order.

[0038] Figure 14 It is a diagram illustrating the problems in previous technologies.

[0039] Figure 15 This is a diagram illustrating the effects of the technology based on the present invention.

[0040] Figure 16 This diagram illustrates the still image acquisition process according to a variation of the first embodiment.

[0041] Figure 17 This is a timing diagram showing the operation timing of each part of the X-ray imaging system according to the second embodiment.

[0042] Figure 18 This is a diagram showing the structure of the X-ray imaging system according to the third embodiment. Detailed Implementation

[0043] [First Implementation]

[0044] Figure 1 This diagram illustrates the structure of an X-ray imaging system 10 that uses X-rays as radiation. The X-ray imaging system 10 includes an X-ray source 11, a radiation source control device 12, an electronic cassette 13, a control console 14, and an optical camera 15. In this embodiment, the control console 14 and the optical camera 15 constitute a photographic aid 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.

[0045] In the X-ray imaging system 10, the electronic cassette 13 is positioned opposite the X-ray source 11. By positioning the subject H between the X-ray source 11 and the electronic cassette 13, the imaging portion of the subject H can be visualized. Figure 1X-ray imaging is performed on the knee (in the middle). The X-ray source 11 and the electron cassette 13 constitute an X-ray imaging apparatus. This X-ray imaging apparatus is an example of a radiographic imaging apparatus related to the technology of this invention.

[0046] The electronic cassette 13 can be configured on a standing or supine radiography table. In this embodiment, after the subject H is positioned by a radiology technician (hereinafter referred to as technician) RG, the technician RG performs the X-ray imaging operation.

[0047] X-ray source 11 includes an X-ray tube 11A that generates X-rays and a collimator 11B that defines the area to be irradiated by X-rays, namely the irradiation field RF. X-ray source 11 may have an irradiation field display light source (not shown) that emits irradiation field display light showing the irradiation field RF on the X-ray incident surface 13A of the electronic cassette 13.

[0048] X-ray tube 11A has a filament that releases thermionic electrons and a target from which the thermionic electrons released from the filament collide and emit X-rays. Collimator 11B, for example, is formed by arranging four lead plates that block X-rays on each side of a quadrilateral, creating a quadrilateral irradiation opening in the center through which X-rays are transmitted. In this case, collimator 11B sets the irradiation field RF by changing the size of the irradiation opening by moving the position of the lead plates.

[0049] The X-ray source control device 12 includes a touch panel 12A, a voltage generating unit 12B, and a control unit 12C. The touch panel 12A is operated by a technician RG when setting the X-ray irradiation conditions and the size of the irradiation opening of the collimator 11B. The X-ray irradiation conditions include the tube voltage, tube current, and X-ray irradiation time applied to the X-ray source 11.

[0050] The voltage generating unit 12B generates a tube voltage applied to the X-ray tube 11A. The control unit 12C controls the operation of the voltage generating unit 12B to set the tube voltage, tube current, and X-ray irradiation time to values ​​set via the touch panel 12A. The control unit 12C has a timer that starts counting when X-rays are generated from the X-ray tube 11A. For example, when 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 opening to the size set via the touch panel 12A.

[0051] 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 a technician RG when X-ray irradiation begins. If the irradiation switch 16 is operated, the X-ray source control device 12 causes the X-ray tube 11A to generate X-rays. As a result, X-rays are irradiated toward the irradiation field RF.

[0052] The electronic cassette 13 detects an X-ray image XP based on X-rays emitted from the X-ray source 11 and transmitted through a radiographic part of the subject H. The electronic cassette 13 has a wireless communication unit and a battery, and operates wirelessly. The electronic cassette 13 wirelessly transmits the detected X-ray image XP to the control console 14. The X-ray image XP is an example of a radiographic image.

[0053] The electronic cassette 13 of this embodiment is not a synchronous type that starts operating in response to receiving a control signal from the control console 14, but rather an asynchronous type (non-synchronous type) that detects X-rays irradiated from the X-ray source 11 and automatically starts operation control. Therefore, the electronic cassette 13 has an irradiation start detection function that detects the start of X-ray irradiation by detecting X-rays irradiated from the X-ray source 11. Furthermore, when the start of X-ray irradiation is detected, the electronic cassette 13 wirelessly transmits an irradiation start detection signal SI to the control console 14. The irradiation start detection signal SI is an example of a timing signal involved in the technology of this invention.

[0054] Furthermore, the X-ray source 11 is suspended vertically downwards from the ceiling 2 of the radiography studio. The X-ray source 11 is held by a suspension holding mechanism 17. The suspension holding mechanism 17 is mounted on 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 freely raised and lowered in the vertical direction (±Z direction). The horizontal movement mechanism 18 holds the suspension holding mechanism 17 so that it can be freely moved along the X-ray irradiation axis direction (±X direction) and in a direction orthogonal to the X-ray irradiation axis direction (±Y direction).

[0055] Motors (not shown) are respectively provided in the suspension holding mechanism 17 and the horizontal moving mechanism 18, enabling the X-ray source 11 to be moved in various directions manually or electrically. The operation of the suspension holding mechanism 17 and the horizontal moving mechanism 18 is controlled by the control unit 12C. The X-ray source 11 can be moved manually or electrically via the touch panel 12A. By moving the X-ray source 11, the position of the irradiation field (RF) can be adjusted.

[0056] The optical camera 15 is an optical digital camera comprising a CMOS (Complementary Metal Oxide Semiconductor) image sensor or a CCD (Charge Coupled Device) image sensor, and, as an example, performs visible light-based photography. The optical camera 15 is capable of both still image photography and video recording. The optical camera 15 is an example of a video recording device according to the technology of this invention.

[0057] The optical axis of the optical camera 15 is parallel to the illumination axis of the X-rays passing through the center of the illumination field RF. The optical camera 15 generates an optical image by optically photographing the region containing the illumination field RF. The optical image is an image showing the photographic portion of the subject H located within the illumination field RF. The optical image can be, for example, a color still image or a moving image.

[0058] The optical camera 15 is mounted on the outer periphery of the X-ray source 11. Alternatively, the optical camera 15 may not be mounted on the outer periphery of the X-ray source 11, but may be built into the X-ray source 11. Furthermore, the objective lens and the imaging element in the optical camera 15 may be separate components. In this case, the objective lens may be disposed on the outer periphery of the X-ray source 11, and the imaging element may be built into a part other than the X-ray source 11 (e.g., the arm supporting the X-ray source 11).

[0059] The optical camera 15 is connected to the control console 14 via wired or wireless means. The control console 14 functions as a photography control device to control the photographic actions of the optical camera 15. In addition to enabling the optical camera 15 to perform still image photography in conjunction with the irradiation start detection signal ST sent from the electronic cassette 13, the control console 14 also enables it to perform motion image photography during the photography preparation period before the start of X-ray photography. For example, the control console 14 is located in an operating room adjacent to the photography room where the X-ray source 11 is located.

[0060] When the control console 14 receives the illumination start detection signal SI from the electronic cassette 13, it sends a still image photography instruction signal to the optical camera 15. The optical camera 15 performs still image photography on the area containing the illumination field RF according to the still image photography instruction signal input from the control console 14. The optical image obtained through this still image photography (hereinafter referred to as the still image SP) is sent to the control console 14.

[0061] When technician RG performs the operation to prepare for the start of photography, console 14 sends a motion image photography start signal to optical camera 15. Optical camera 15 begins motion image photography of the area containing the illumination field RF based on the motion image photography start signal input from console 14. The optical image obtained through this motion image photography (hereinafter referred to as the motion image MP) is sent to console 14 in real time as a so-called instant preview image during motion image photography.

[0062] The console 14 is connected via network N to the RIS (Radiology Information System), PACS (Picture Archiving and Communication System), and radiographic loss management system 19, all installed in the X-ray imaging system 10. The console 14 has the function of performing X-ray imaging through operation by technicians RG based on imaging orders and various information obtained from the RIS. Furthermore, the console 14 has the function of sending the X-ray image XP received from the electronic cassette 13 after X-ray imaging to the PACS.

[0063] Furthermore, the console 14 has the function of sending X-ray images XP that have been determined by technician RG to be of photographic loss after X-ray imaging to the photographic loss management system 19. The photographic loss management system 19 collects the X-ray images XP that have been determined to be of photographic loss and performs a cause analysis of the photographic loss.

[0064] Figure 2 The structure of the electronic cassette 13 is shown. The electronic cassette 13 consists of a sensor panel 20, a circuit section 21, and a portable rectangular frame 22 that houses these components. The frame 22 is, for example, of a size similar to that of a film cassette, an IP (Imaging Plate) cassette, or a CR (Computed Radiography) cassette, conforming to the international standard ISO (International Organization for Standardization) 4090:2001.

[0065] The electronic cassette 13 is positioned with its X-ray incident surface 13A, which serves as the upper surface of the frame 22, facing the X-ray source 11, and X-rays are irradiated onto the X-ray incident surface 13A. In addition, although not shown in the diagram, the frame 22 is equipped with a switch for switching the main power supply on / off, an indicator for the remaining battery life, and a status indicator for the completion of photographic preparation, among other operational status indicators for the electronic cassette 13.

[0066] The sensor panel 20 comprises a scintillator 20A and a photodetector substrate 20B. The scintillator 20A and photodetector substrate 20B are stacked in the order of scintillator 20A and photodetector substrate 20B when viewed from the X-ray incident surface 13A. The scintillator 20A has a phosphor such as CsI:Tl (thallium-activated cesium iodide) or GOS (Gd₂O₂S:Tb, terbium-activated gadolinium oxysulfide) to convert X-rays incident through the X-ray incident surface 13A into visible light for emission. Alternatively, a sensor panel in which the photodetector substrate 20B and scintillator 20A are stacked in the order of photodetector substrate 20B when viewed from the X-ray incident surface 13A can also be used. Furthermore, a direct conversion type sensor panel that directly converts X-rays into signal charges using a photoconductive film such as amorphous selenium can also be used.

[0067] The photodetector substrate 20B detects the visible light emitted from the scintillator 20A and converts it into electrical charge. The circuit section 21 controls the driving of the photodetector substrate 20B and generates an X-ray image XP based on the charge output from the photodetector substrate 20B.

[0068] Figure 3 This illustrates the structure of the photodetector substrate 20B. The photodetector substrate 20B includes a pixel region 30, a gate driver 31, a signal processing circuit 32, an illumination start detection unit 33, a control unit 34, and a communication interface (I / F) 35.

[0069] Pixel region 30 has a plurality of ordinary pixels 40A arranged in a matrix along mutually orthogonal X and Y directions. The ordinary pixels 40A are X-ray image generation pixels used to detect X-rays and generate an X-ray image XP. Furthermore, in addition to the ordinary pixels 40A, pixel region 30 also includes detection pixels 40B. The detection pixels 40B are irradiation start detection pixels used to detect the start of X-ray irradiation.

[0070] Typically, pixel 40A includes: a photoelectric conversion unit 41, which generates and stores charge by photoelectric conversion of visible light converted by a scintillator; and a TFT 42, which is a switching element. The photoelectric conversion unit 41, for example, has a PIN (p-intrinsic-n) type semiconductor layer, an upper electrode disposed on the upper side of the semiconductor layer, and a lower electrode disposed on the lower side of the semiconductor layer. A bias voltage is applied to the upper electrode. The lower electrode is connected to the TFT (Thin Film Transistor) 42.

[0071] The detection pixel 40B has the same photoelectric conversion unit 41 and TFT 42 as the normal pixel 40A. However, in the detection pixel 40B, the source electrode and drain electrode of the TFT 42 are short-circuited. Hereinafter, without distinguishing between the normal pixel 40A and the detection pixel 40B, they will be referred to simply as pixel 40.

[0072] Pixel region 30 has a plurality of scan lines 43 extending along the X direction and a plurality of signal lines 44 extending along the Y direction. The scan lines 43 and signal lines 44 are wired in a grid pattern. Pixel 40 is connected to the intersection of the scan lines 43 and the signal lines 44. Specifically, in pixel 40, the gate electrode of TFT 42 is connected to the scan line 43, and the source electrode of TFT 42 is connected to the signal line 44. Furthermore, the drain electrode of TFT 42 is connected to the photoelectric conversion unit 41.

[0073] Each scan line 43 is connected to a pixel 40 representing one pixel row. Each signal line 44 is connected to a pixel 40 representing one pixel column. Each scan line 43 is connected to a gate driver 31. Each signal line 44 is connected to a signal processing circuit 32.

[0074] The gate driver 31 sequentially supplies gate pulses as scan signals to each scan line 43. The gate pulses supplied to the scan line 43 are applied to the gate electrode of the TFT 42 included in the pixel 40 connected to the scan line 43.

[0075] The charge accumulated in the photoelectric conversion unit 41 of the normal pixel 40A is output to the signal line 44 when the TFT 42 is turned on. In the detection pixel 40B, the source electrode and drain electrode of the TFT 42 are short-circuited, so the charge generated in the photoelectric conversion unit 41 of the detection pixel 40B is output to the signal line 44 regardless of the switching state of the TFT 42.

[0076] The signal processing circuit 32 includes an integrator that functions as a charge amplifier, a CDS (correlated double sampling) circuit, and an analog-to-digital (A / D) converter. After accumulating the charge input from each pixel 40 via signal line 44 using the integrator, the signal processing circuit 32 performs correlated double sampling using the CDS circuit. Then, the signal processing circuit 32 converts the pixel signal, after removing reset noise components through correlated double sampling, into a digital signal using the A / D converter.

[0077] The signal processing circuit 32 generates an X-ray image XP based on the pixel signal of one frame read from each normal pixel 40A of the pixel region 30.

[0078] The irradiation start detection unit 33 performs X-ray irradiation start detection based on the pixel signal output from the detection pixel 40B via the signal processing circuit 32. The irradiation start detection unit 33 monitors the pixel signal output from the detection pixel 40B. Figure 4 As shown, when the pixel signal output from the detection pixel 40B exceeds the threshold Vth, the irradiation start detection unit 33 determines that X-ray irradiation has started and outputs the irradiation start detection signal SI.

[0079] For example, the illumination start detection unit 33 performs illumination start detection based on the maximum value of the pixel signals output from the plurality of detection pixels 40B. Alternatively, the illumination start detection unit 33 may perform illumination start detection based on an average value or a total value instead of the maximum value. Furthermore, the illumination start detection unit 33 may also perform illumination start detection based on the time-varying rate of the pixel signals.

[0080] The control unit 34 is composed of a microcomputer and includes a CPU (Central Processing Unit), memory, and storage devices. The control unit 34 controls X-ray imaging by executing programs stored in the memory via the CPU. The control unit 34 controls the gate driver 31, signal processing circuit 32, irradiation start detection unit 33, and communication I / F 35.

[0081] If the X-ray irradiation start detection unit 33 detects the start of X-ray irradiation, the control unit 34 controls the gate driver 31 and the signal processing circuit 32 to perform a reset operation on the charge accumulated in the normal pixel 40A. Specifically, the control unit 34 supplies gate pulses to each scan line 43 from the gate driver 31, outputs the accumulated charge of each normal pixel 40A to the signal line 44, and discards the charge in the signal processing circuit 32. After the reset operation is completed, the control unit 34 sets all TFTs 42 to the off state, thereby setting the normal pixel 40A to the charge accumulation state.

[0082] After setting the normal pixel 40A to a charge accumulation state, the control unit 34 controls the gate driver 31 to read the pixel signal from the normal pixel 40A to the signal processing circuit 32 after a predetermined X-ray irradiation time, thereby generating an X-ray image XP.

[0083] When the irradiation start detection unit 33 detects the start of X-ray irradiation, the control unit 34 outputs an irradiation start detection signal SI to the control console 14 via the communication I / F 35. Furthermore, after the signal processing circuit 32 generates the X-ray image XP, the control unit 34 outputs the X-ray image XP to the control console 14 via the communication I / F 35.

[0084] exist Figure 5 In this system, the console 14 includes a display 50, an input device 51, a CPU 52, a memory 53, a storage device 54, and a communication unit 55. These components are interconnected via a data bus 56.

[0085] The display 50 is a display unit that displays various operation screens, X-ray images (XP), and optical images (still images (SP) and moving images (MP)) with GUI (Graphical User Interface) operation functions. The input device 51 is an input operation unit that includes a touch panel or keyboard, etc.

[0086] Storage device 54 is, for example, an HDD (Hard Disk Drive) array, either built into console 14 or externally connected to console 14. External connection is via cable or network. Storage device 54 stores operating system and other control programs, various applications, and various data associated with these programs.

[0087] Memory 53 is the working memory used by CPU 52 for processing. CPU 52 loads the program stored in storage device 54 into memory 53, executes the processing according to the program, and thereby centrally controls the various parts of console 14. Communication unit 55 transmits and receives various data such as X-ray images XP and optical images (still images SP and moving images MP) with electronic cassette 13 and optical camera 15. In addition, communication unit 55 communicates with control unit 12C of X-ray source control device 12.

[0088] Console 14 Receive Figure 6 The input for imaging order 57 is shown. Imaging order 57 is, for example, information from a client requesting imaging in a clinic to instruct technician RG on X-ray imaging. Imaging order 57 is transmitted from RIS to console 14.

[0089] Photography order 57 includes items such as Order TD (Identification Data), Subject ID, and photographic technique. The Order ID is a marker or number that identifies each photography order 57 and is automatically assigned by RIS. The Subject ID field records the Subject ID of the subject H, which is the subject of the photograph. The Subject ID is a marker or number that identifies each subject H.

[0090] Photographic technique refers to information related to the photographic part of the subject H, the pose of that part, and its orientation. The photographic part, besides... Figure 1 Besides the knees, which are shown in the example, other areas include the head, cervical spine, chest, abdomen, hands, fingers, or elbows. Posture refers to the subject H's position, such as standing, lying down, or sitting. Orientation refers to the subject H's orientation relative to the X-ray source 11, such as front, side, or back. In addition to these items, the photography order 57 also includes subject information (patient information) such as the subject H's name, gender, age, height, and weight.

[0091] The storage device 54 of the console 14 stores Figure 7The conditions table 58 is shown. In conditions table 58, corresponding lighting conditions are registered and associated with each photographic technique.

[0092] The console 14, operated by technician RG, displays the following on monitor 50: Figure 6 The photography order list shown is a list of contents for photography order 57. Technician RG can browse the photography order list to confirm the contents of photography order 57. Furthermore, console 14 will... Figure 7 The contents of the conditions table 58 are displayed on the monitor 50. The technician RG can select and set the illumination conditions to match the photographic technique specified in the photographic order 57.

[0093] The console 14 wirelessly transmits a condition setting signal containing various information such as the irradiation conditions set by the technician RG, the order ID, and the console ID as identification information of the console to the electronic cassette 13.

[0094] The console 14 stores the X-ray image XP received from the electronic cassette 13 as an image file, for example, conforming to the DICOM (Digital Imaging and Communication in Medicine) standard, in the storage device 54, which serves as the storage unit. The image file is a file that associates the X-ray image XP with accompanying information via an image ID. The accompanying information includes the order ID, subject ID, patient information, imaging technique, irradiation conditions, etc.

[0095] Furthermore, for the still image SP obtained by still image photography performed in conjunction with the irradiation start signal SI by the optical camera 15, an image ID (optical image ID) corresponding to the image ID (X-ray image ID) of the X-ray image XP obtained by the X-ray photography is assigned. For example... Figure 8 As shown, the X-ray image XP and still image SP obtained during a single X-ray imaging session are associated with the X-ray image ID and optical image ID and stored in the storage device 54.

[0096] When the imaging technique is "knee / bent posture / side view," the doctor mainly diagnoses the joint cavity (JC) of the knee based on the X-ray image (XP). Therefore, the joint cavity (JC) needs to be clearly depicted in the X-ray image (XP).

[0097] Figure 9 The various functions configured in CPU 52 are shown. The operating program 60 is stored in storage device 54. Additionally, although not shown in the diagram, Figure 7 The condition table 58 shown is also stored in the storage device 54. The CPU 52 is configured with multiple functional units by executing the working program 60.

[0098] The operating procedure 60 enables the CPU 52 to function as a still image photography instruction unit 61, a still image acquisition unit 62, a correlation establishment unit 63, a moving image photography instruction unit 64, a moving image acquisition unit 65, an overlay processing unit 66, and a display control unit 67.

[0099] The still image photography instruction unit 61 receives an irradiation start detection signal SI via the communication unit 55. This irradiation start detection signal SI is transmitted from the electronic cassette 13 in response to the pressing of the irradiation switch 16, which initiates the irradiation of X-rays from the X-ray source 11 to the electronic cassette 13. The still image photography instruction unit 61 instructs the optical camera 15 to perform still image photography in accordance with the irradiation start detection signal SI received from the electronic cassette 13.

[0100] The still image acquisition unit 62 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 62 is input to the association establishment unit 63. Furthermore, in the association establishment unit 63, an X-ray image XP detected by the electronic cassette 13 based on the X-rays irradiated from the X-ray source 11 when the irradiation switch 16 is pressed is input via the communication unit 55.

[0101] The association establishment unit 63 inputs the still image SP to the still image acquisition unit 62 and the X-ray image XP input from the electronic cassette 13, as shown in the figure. Figure 8 The association is established and stored in storage device 54 as shown. Additionally, the association establishment unit 63 stores the aforementioned patient information and other supplementary information (see reference). Figure 8 The image is associated with the still image SP and the X-ray image XP that have been established and stored in the storage device 54.

[0102] The motion image photography instruction unit 64 sends a motion image photography start signal to instruct the optical camera 15 to begin motion image photography upon receiving a re-photography preparation start signal RS from the input device 51. Additionally, when the technician RG confirms that the X-ray image XP acquired through X-ray photography has photographic loss, he operates the input device 51 to switch the photography aid to the re-photography preparation mode. For example, if the photographic technique is "knee / bent posture / side view," the technician RG determines it to be photographic loss if, for example, the knee joint cavity JC is not clearly depicted in the X-ray image XP.

[0103] The dynamic image acquisition unit 65 acquires dynamic images (MP) generated by dynamic image photography performed by the optical camera 15 in real time, frame by frame. The dynamic image acquisition unit 65 acquires optical images frame by frame and outputs a dynamic image (MP) composed of multiple acquired frames. The dynamic image (MP) output from the dynamic image acquisition unit 65 is input frame by frame to the overlay processing unit 66.

[0104] The overlay processing unit 66 acquires the still image SP stored in the storage device 54, and as... Figure 10 As shown, still images SP are superimposed on each frame of the moving image MP. The overlay processing unit 66 inputs the overlaid image TP, generated by overlaying the moving image MP and the still image SP, to the display control unit 67 frame by frame. The display control unit 67 displays the overlaid image TP frame by frame on the display 50. That is, the display control unit 67 overlays the still image SP onto the moving image MP to display it on the display 50 in real time.

[0105] The still image SP in the overlaid image TP is correlated with the X-ray image XP, which the technician RG determined to be a photographic loss, showing the position of the subject H at the time of photographic loss. The moving image MP in the overlaid image TP shows the current position of the subject H in preparation for re-photographing. Therefore, the technician RG can determine the current position of the subject H relative to the time of photographic loss by checking the overlaid image TP displayed in real time on the display 50.

[0106] The motion image capture by the optical camera 15 ends upon receiving an execution instruction for still image capture from the aforementioned still image capture instruction unit 61. Furthermore, after the motion image capture ends, the motion image MP is not stored in the storage device 54 but is discarded. This is to prevent unnecessary information from being captured in the motion image MP during the capture preparation period, thus protecting privacy. The still image acquisition unit 62 can acquire one frame of the motion image MP as a still image SP.

[0107] Furthermore, the display control unit 67 displays a console screen on the monitor 50, allowing technicians RG to perform various operations such as selecting photography orders 57 using the input device 51. Additionally, the display control unit 67 displays X-ray images XP or overlay images TP on the console screen.

[0108] Figure 11 This represents an example of a console screen displayed on the monitor 50 by the display control unit 67. For example... Figure 11 As shown, the console screen 70 is equipped with an image display area 70A for displaying X-ray images XP or overlay images TP, etc.

[0109] Furthermore, the console screen 70 displays a first operation button 71 for re-photographing, a second operation button 72 for outputting the X-ray image XP determined to be of photographic loss to the photographic loss management system 19, and a third operation button 73 for outputting the X-ray image XP to the PACS. The first operation button 71, the second operation button 72, and the third operation button 73 are operated via a touch panel formed on the screen of the display 50.

[0110] Figure 11 This shows an example of the console screen 70 after X-ray imaging. Figure 11 In the example shown, an X-ray image XP obtained through X-ray imaging is displayed in image display area 70A. If the technician RG determines that the X-ray image XP is not suitable for diagnosis and requires re-imaging (i.e., imaging loss), they can send the X-ray image XP to the imaging loss management system 19 by pressing the second operation button 72. At this time, the technician RG can then press the first operation button 71 to initiate the imaging preparation process for re-imaging on the X-ray imaging system 10.

[0111] On the other hand, when the technician RG determines that the X-ray image XP is suitable for diagnosis and does not require re-photographing, he can send the X-ray image XP to the PACS by pressing the third operation button 73.

[0112] Additionally, when the console 14 sends the X-ray image XP to an external system such as the radiographic loss management system 19 or PACS, it preferably outputs a file that links patient information and other accompanying information with the still image SP and the X-ray image XP, which have already been linked by the linking unit 63 (see reference). Figure 8 ).

[0113] Figure 12 This is an example of the control panel screen 70 during the preparation for reshooting. Figure 12 In the example shown, an overlay image TP, which is a still image SP superimposed on a moving image MP, is displayed in image display area 70A. The still image SP shows the position of the subject H at the time of photographic loss. The moving image MP shows the current position of the subject H during the photographic preparation action. Thus, the technician RG can locate the subject H while referring to the still image SP, which shows the position of the subject H at the time of photographic loss.

[0114] Next, refer to Figure 13 The flowchart shown illustrates the function of the photographic aid device described above. First, before taking photographs, the technician RG confirms the contents of the photographic order 57 via the display 50 and sets the irradiation conditions using the input device 51 and touch panel 12A. Next, the technician RG positions the X-ray source 11, the electronic cassette 13, and the subject H according to the photographic technique included in the photographic order 57. Here, the photographic technique is set to "knee / bent posture / side view". The technician RG bends one leg of the subject H, positioning the subject H so 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 (see reference). Figure 1 ).

[0115] The still image imaging instruction unit 61 determines whether it has received an irradiation start detection signal SI from the electronic cassette 13 (step S10). The irradiation start detection signal SI is a timing signal that is detected by the irradiation start detection unit 33 of the electronic cassette 13 and sent to the control console 14 in response to the start of X-ray irradiation from the X-ray source 11 to the electronic cassette 13 when the irradiation switch 16 is pressed by the technician RG. After the start of X-ray irradiation is detected by the irradiation start detection unit 33, the electronic cassette 13 detects the X-ray image XP of the subject H based on the X-rays transmitted through the subject H.

[0116] If the still image imaging instruction unit 61 receives the irradiation start detection signal SI (step S10: Yes), it instructs the optical camera 15 to perform still image imaging (step S11). The still image acquisition unit 62 acquires the still image SP generated by the still image imaging performed by the optical camera 15 (step S12). Furthermore, the control console 14 acquires the X-ray image XP detected by the electronic cassette 13 (step S13).

[0117] Next, the association establishment unit 63 establishes an association between the acquired X-ray image XP and the still image SP and saves them in the storage device 54 (step S14). The display control unit 67 displays the X-ray image XP saved in the storage device 54 in the image display area 70A of the console screen 70 (step S15).

[0118] Next, CPU52 determines whether there is an instruction for image output by technician RG pressing the third operation button 73 (step S16). Technician RG confirms the X-ray image XP (reference) displayed in image display area 70A. Figure 11 If it is determined that no re-photographing is required, the CPU 52 instructs the image output by pressing the third operation button 73. When the CPU 52 determines that the third operation button 73 has been pressed (step S16: Yes), it outputs the X-ray image XP stored in the storage device 54 to the PACS (step S25) and ends the processing.

[0119] On the other hand, when technician RG confirms the X-ray image XP displayed in image display area 70A and determines that re-photographing is necessary, he instructs the X-ray image XP to be sent to the photography loss management system 19 by pressing the second operation button 72. Afterwards, technician RG instructs the start of preparation for re-photographing by pressing the first operation button 71. If the first operation button 71 is pressed, the input device 51 generates a re-photographing preparation start signal RS and sends it to the moving image photography instruction unit 64.

[0120] If it is determined in step S16 that the third operation button 73 has not been pressed (step S16: No), the motion image photography instruction unit 64 determines whether a re-photography preparation start signal RS has been received from the input device 51 (step S17). If the motion image photography instruction unit 64 receives the re-photography preparation start signal RS (step S17: Yes), it sends a motion image photography start signal to the optical camera 15 (step S18). The motion image acquisition unit 65 acquires the motion image MP generated by the motion image photography performed by the optical camera 15 frame by frame (step S19).

[0121] Next, the overlay processing unit 66 acquires the still image SP stored in the storage device 54 and performs a process of overlaying the still image SP onto the frames of the moving image MP acquired by the moving image acquisition unit 65, thereby generating an overlay image TP (step S20). The display control unit 67 displays the overlay image TP generated by the overlay processing unit 66 on the image display area 70A of the console screen 70 (step S23).

[0122] Technician RG confirmed the overlay image TP (reference) displayed in image display area 70A. Figure 12 The system can locate the subject H while simultaneously viewing a still image SP showing the position of the subject H at the time of photographic loss. Once the subject H is located, the technician RG instructs the X-ray imaging process by pressing the irradiation switch 16.

[0123] The still image photography instruction unit 61 performs the same determination as in step S10 regarding whether it has received the illumination start detection signal SI from the electronic cassette 13 (step S24). During the period when the still image photography instruction unit 61 does not receive the illumination start detection signal SI (step S24: No), the process returns to step S19, and the moving image acquisition unit 65 acquires the next frame of the moving image MP. During the period before the illumination start detection signal SI is received, steps S19 to S24 are repeatedly executed. As a result, the overlapping image TP of the still image SP superimposed on the moving image MP is displayed in real time in the image display area 70A.

[0124] If the technician RG presses the illumination switch 16 and the still image photography instruction unit 61 receives the illumination start detection signal ST (step S24: Yes), then the still image photography instruction unit 61 instructs the optical camera 15 to perform still image photography (step S11). If the optical camera 15 receives the still image photography execution instruction, it ends the dynamic image photography and performs still image photography. Thereafter, the same process is performed.

[0125] The effect of the photographic aid device with the above structure will be explained. After the technician RG presses the irradiation switch 16, it takes a certain amount of time for the X-ray source control device 12 to generate X-rays from the X-ray tube 11A. Therefore, a time lag occurs from the time the irradiation switch 16 is pressed until the start of X-ray irradiation. In particular, the time lag is greater when the irradiation switch 16 is a two-stage switch capable of both half-press and full-press operation. When the irradiation switch 16 is a two-stage switch, for example, preheating of the X-ray tube 11A begins corresponding to the irradiation switch 16 being half-pressed. After preheating is completed, when the irradiation switch 16 is fully pressed, the X-ray tube 11A generates X-rays. Since the preheating of the X-ray tube 11A requires a certain amount of time, the time lag is greater.

[0126] Therefore, assuming that still image photography based on optical camera 15 is performed at the time when illumination switch 16 is pressed, still image photography is actually performed before X-ray photography. Consequently, a discrepancy occurs in the acquisition time of the X-ray image XP and still image SP stored in storage device 54 by the association establishment unit 63. If a discrepancy occurs in the acquisition time of X-ray image XP and still image SP, the still image SP in the overlapping image TP is not an image that accurately represents the position of the subject H at the time of photographic loss. Therefore, the positioning accuracy of the subject H during re-photography is reduced, and photographic loss may occur again.

[0127] In contrast, in the photographic aid device described above, the CPU 52 performs still image photography based on the optical camera 15 at the timing when the irradiation start detection signal SI is received from the electronic cassette 13, rather than at the timing when the irradiation switch 16 is pressed. As a result, the deviation in the acquisition time between the X-ray image XP and the still image SP, which are associated by the association establishment unit 63, is reduced, and the positioning accuracy of the subject H during re-photographing is improved. Consequently, the possibility of photographic loss occurring again through re-photographing is reduced, and the X-ray-based radiation dose to the subject H can be suppressed.

[0128] Furthermore, when technician RG uses only the X-ray image XP to determine whether re-photographing is necessary, there is a possibility that an unnecessary re-photograph might be incorrectly identified as photographic loss, leading to unnecessary re-photographing. Also, depending on the physical characteristics of the subject H, sometimes re-photographing may not improve the situation. In such cases, unnecessary re-photographing may be repeatedly performed. In contrast, the photographic aid device described above can acquire both the X-ray image XP and the still image SP, which have minimal time-delay. Therefore, by using the still image SP, which was acquired simultaneously with the X-ray image XP, in determining whether re-photographing is necessary, a more accurate assessment can be made.

[0129] The following is for reference. Figure 14 and Figure 15 The effects of the photographic aid device based on the above structure on the positioning of the subject H will be explained. During X-ray imaging, sometimes even if the technician RG believes the subject H is accurately positioned based on the imaging location, it is not actually accurately positioned, resulting in photographic 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 radial beams emanating from the focal point of the X-ray source 11. Therefore, due to slight positional shifts in the joint, the incident angle of the X-rays changes, causing the depiction of the joint cavity JC to become unclear. Unclear depiction of the joint cavity JC constitutes photographic loss, requiring re-irradiation.

[0130] When re-photographing is required due to photographic loss, the technician RG needs to reposition the subject H. When adjusting for slight positional shifts in subject H during re-photographing, minor adjustments are typically made based on the original position of subject H at the time of photographic loss.

[0131] However, as Figure 14 As shown, in conventional devices without optical cameras, if the subject H has moved significantly since the occurrence of photographic loss, the technician RG cannot accurately determine the position of subject H at the time of the loss, thus making fine adjustments impossible. If the technician RG repositions subject H from scratch, there is a high probability that subject H will be repositioned to the same location, resulting in further photographic loss. Furthermore, even if subject H is positioned using an optical camera or similar device before X-ray imaging, the technician RG cannot determine the position of subject H at the time of the loss, leading to a high probability of repeated photographic loss and necessitating repeated re-enhancing.

[0132] In contrast, such as Figure 15 As shown, in the technology of this invention, an X-ray image XP and an optical image (still image SP) showing the subject H are acquired in conjunction with the start of X-ray irradiation. Therefore, even if the subject H has moved significantly since the start of the imaging loss, the technician RG can easily determine the position of the subject H at the time of the imaging loss. Thus, after positioning the subject H at the position at the time of the imaging loss, the technician RG can fine-tune the position of the subject H from that position according to the reasons for the imaging loss. After fine-tuning the position of the subject H, a re-imaging is performed, thereby obtaining a good X-ray image XP. Thus, according to the technology of this invention, repeated re-imaging can be suppressed. As a result, unnecessary radiation exposure to the subject H can be suppressed and the examination time can be shortened.

[0133] Furthermore, in the technology of this invention, an overlaid image TP is obtained by real-time display of an optical image (still image SP) acquired in conjunction with the start of X-ray irradiation and the current optical image (moving image MP) of the subject H. Even if the subject H moves significantly from the point of photographic loss, the technician RG can more easily determine the position of the subject H at the time of photographic loss based on the still image SP in the overlaid image TP.

[0134] [Modifications of the first embodiment]

[0135] Next, a variation of the first embodiment of the present invention will be described. In the first embodiment, the still image acquisition unit 62 acquires a still image SP obtained by receiving an instruction from the still image photography instruction unit 61 and performing still image photography by the optical camera 15. Instead, in this variation, the still image acquisition unit 62 extracts one frame from the moving image MP based on the illumination start detection signal SI sent from the electronic cassette 13, and acquires the extracted frame as the still image SP.

[0136] Specifically, such as Figure 16 As shown, the still image acquisition unit 62 extracts the frame F corresponding to the moment when the illumination start detection signal SI is received from the electronic dark box 13 from the multiple frames F constituting the dynamic image MP acquired by the dynamic image acquisition unit 65. Then, the still image acquisition unit 62 uses the extracted frame F as the still image SP and discards the remaining frames F other than the extracted frame F.

[0137] The still image acquisition unit 62 may also store in advance the moment when the irradiation start detection signal SI is received from the electronic cassette 13, and extract frame F from the moving image MP after the X-ray imaging ends. At this time, the moving image MP acquired by the moving image acquisition unit 65 is stored in the storage device 54, etc., in advance, and after extracting the frame F corresponding to the moment of receiving the irradiation start detection signal SI as a still image SP, the moving image MP is deleted from the storage device 54, etc.

[0138] The still image SP acquired by the still image acquisition unit 62 is associated with the X-ray image XP by the association establishment unit 63 in the same way as in the first embodiment and stored in the storage device 54.

[0139] The other structures of the X-ray imaging system involved in this variation are the same as those of the X-ray imaging system 10 involved in the first embodiment.

[0140] [Second Implementation]

[0141] Next, the second embodiment of the present invention will be described. In the first embodiment, the asynchronous electronic cassette 13 was used as a radiation image detector, but in the second embodiment, the synchronous electronic cassette 13B is used as a radiation image detector. In this embodiment, the electronic cassette 13B starts operating upon receiving a control signal from the control console 14. Therefore, the irradiation start detection unit 33 is not configured in the electronic cassette 13B.

[0142] In the second embodiment, before X-ray irradiation begins from the X-ray source 11, the control console 14 sends a preparation request signal REQ to the electronic cassette 13B requesting preparation for X-ray detection. If the electronic cassette 13B receives the preparation request signal REQ, it performs the aforementioned reset operation and then sends a preparation complete signal RDY to the control console 14, indicating that X-ray detection preparation is complete. The control console 14, in conjunction with the preparation complete signal RDY sent from the electronic cassette 13B, causes the optical camera 15 to perform still image photography. The preparation complete signal RDY is an example of a timing signal involved in the technology of this invention.

[0143] Next, the timing of the operation of each part of the X-ray imaging system according to the second embodiment will be explained in more detail. Figure 17 This is a timing diagram showing the operation timing of each part of the X-ray imaging system according to the second embodiment. In this embodiment, the irradiation switch 16 is configured as the aforementioned two-stage switch.

[0144] like Figure 17 As shown, if the irradiation switch 16 is half-pressed, a first operation signal S1 is sent from the irradiation switch 16 to the X-ray source control device 12. If the X-ray source control device 12 receives the first operation signal S1, it causes the X-ray source 11 to start preheating of the X-ray tube 11A.

[0145] Next, if the irradiation switch 16 is fully pressed, a second operation signal S2 is sent from the irradiation switch 16 to the radiation source control device 12. If the radiation source control device 12 receives the second operation signal S2, the control console 14 sends a preparation request signal REQ to the electronic cassette 13B. After performing a reset operation, the electronic cassette 13B sends a preparation completion signal RDY to the control console 14. If the control console 14 receives the preparation completion signal RDY, it causes the X-ray source 11 to begin X-ray irradiation. Furthermore, if the control console 14 receives the preparation completion signal RDY, it instructs the optical camera 15 to perform still image photography via the still image photography instruction unit 61.

[0146] After sending a preparation request signal REQ to the control console 14, the electronic cassette 13B begins charge accumulation for X-ray imaging after a predetermined time T. The predetermined time T is a value greater than or equal to 0. Upon receiving an instruction to perform still image imaging, the optical camera 15 begins charge accumulation for still image imaging.

[0147] After a predetermined X-ray irradiation time, console 14 sends an irradiation end signal STP to electronic cassette 13B. Upon receiving the irradiation end signal STP, electronic cassette 13B performs a readout operation, thereby generating an X-ray image XP. After starting charge accumulation, optical camera 15 performs a readout operation after a predetermined exposure time, thereby generating a still image SP.

[0148] The other structures of the X-ray imaging system according to the second embodiment are the same as those of the X-ray imaging system 10 according to the first embodiment.

[0149] [Third Implementation]

[0150] Next, a third embodiment of the present invention will be described. In the first embodiment, the control console 14 causes the optical camera 15 to perform still image photography based on an illumination start detection signal SI sent from the electronic cassette 13. Instead, in the third embodiment, the control console 14 causes the optical camera 15 to perform still image photography based on a signal sent from an automatic exposure controller that is separately provided from the electronic cassette 13.

[0151] Figure 18 This illustrates the structure of the X-ray imaging system according to the third embodiment. For example... Figure 18 As shown, in this embodiment, an AEC (Automatic Exposure Control) sensor 80, serving as an automatic exposure controller, is disposed near the electronic cassette 13. In this embodiment, the electronic cassette 13 is held on a camera stage 81. The camera stage 81 is a standing or lying camera stage, etc. The AEC sensor 80 is held on the camera stage 81 and disposed on the front or back surface of the electronic cassette 13.

[0152] The AEC sensor 80 is a sensor that measures the linear amount of X-rays transmitted through the subject H, and sends a linear amount detection signal Sd to the control console 14. The control console 14 sends the detection signal Sd to the control unit 12C of the X-ray source control device 12. After the irradiation of X-rays based on the X-ray source 11 begins, the control unit 12C stops the irradiation of X-rays based on the X-ray source 11 when the accumulated linear amount reaches the target linear amount, based on the linear amount detection signal Sd. This irradiation cessation is performed even before the irradiation time included in the preset X-ray irradiation conditions is reached.

[0153] The linearity detection signal Sd sent from the AEC sensor 80 to the control console 14 is also supplied to the still image photography instruction unit 61. In this embodiment, the still image photography instruction unit 61 instructs the optical camera 15 to perform still image photography upon receiving the detection signal Sd. The detection signal Sd is an example of a radiation detection signal output from the automatic exposure controller.

[0154] The other structures of the X-ray imaging system according to the third embodiment are the same as those of the X-ray imaging system 10 according to the first embodiment. In this embodiment, the deviation in the acquisition time of the X-ray image XP and the still image SP can also be reduced in the same way as in the first embodiment.

[0155] In the X-ray imaging systems described in the above embodiments, the optical image and the radiographic image acquired by the optical camera are correlated based on a timing signal sent from the radiographic image detector side. By acquiring the optical image based on the timing signal sent from the radiographic image detector side, the time discrepancy between the acquisition of the radiographic image and the optical image can be reduced.

[0156] in addition, Figure 16 The variations of the first embodiment shown can be applied to either the second or third embodiment.

[0157] The above embodiments are illustrated by taking an X-ray imaging system set up in a radiography studio as an example, but the X-ray imaging system can also be a system that utilizes a so-called mobile medical vehicle.

[0158] Furthermore, the technology of the present invention is not limited to X-rays, but can also be applied to systems that use other types of radiation, such as gamma rays, to photograph a subject.

[0159] In the above embodiments, for example, the hardware structure of the processing units that perform various processes, such as the still image photography instruction unit 61, the still image acquisition unit 62, the association establishment unit 63, the moving image photography instruction unit 64, the moving image acquisition unit 65, the overlay processing unit 66, and the display control unit 67, is the various processors shown below.

[0160] Processors include CPUs, programmable logic devices (PLDs), and special-purpose circuits. As is well known, a CPU is a general-purpose processor that executes software (programs) to function as various processing units. A PLD is a processor such as a field-programmable gate array (FPGA) whose circuit structure can be modified after manufacturing. Special-purpose circuits are processors with circuit structures specifically designed to perform specific processes, such as application-specific integrated circuits (ASICs).

[0161] A processing unit can consist of one of these various processors, or it can consist of a combination of two or more processors of the same or different types (e.g., multiple FPGAs or a combination of a CPU and an FPGA). Furthermore, multiple processing units can also be composed of a single processor.

[0162] As examples of a single processor comprising multiple processing units, firstly, there are processors that combine one or more CPUs and software to form a single processor, which functions as multiple processing units. Secondly, there are systems-on-chips (SoCs), which use a single IC chip to implement the functions of the entire system containing multiple processing units. Thus, various processing units are constructed as hardware structures using one or more of the aforementioned processors.

[0163] Moreover, the hardware structure of these various processors, more specifically, is capable of utilizing circuits that combine circuit elements such as semiconductor elements.

[0164] This invention is not limited to the embodiments described above. Various structures can be employed as long as they do not depart from the spirit of the invention. Furthermore, in addition to programs, this invention also relates to a computer-readable storage medium that non-temporarily stores programs.

Claims

1. A photographic aid device for use in a radiographic imaging apparatus, The radiographic apparatus includes a radiation source and a radiation image detector for detecting a radiation image of a subject based on radiation irradiated from and transmitted through the radiation source. The radiographic aid includes: An optical camera acquires optical images frame by frame by optically photographing a region including an irradiation field of radiation from the radiation source illuminating the subject, and outputs a dynamic image consisting of multiple acquired frames; and At least one processor, The processor, based on a timing signal sent from the radiation image detector, associates a frame of the optical image acquired by the optical camera as a still image with the radiation image that the technician determines to have photographic loss. The still image is overlaid on frames of a moving image generated by capturing moving images through the optical camera and displayed on a monitor.

2. The photographic auxiliary device according to claim 1, wherein, The timing signal is the irradiation start detection signal output from the radiation image detector with the function of detecting the start of radiation irradiation.

3. The photographic auxiliary device according to claim 1, wherein, The timing signal is a radiation detection signal output from an automatic exposure controller that is separate from the radiation image detector.

4. The photographic auxiliary device according to claim 1, wherein, The timing signal is a preparation completion signal output when the radiation image detector has completed the radiation detection preparation.

5. The photographic aid device according to any one of claims 1 to 4, wherein, The processor associates patient information with the established still images and radiographic images and outputs the association to the outside.

6. A method of operating a photographic aid device, the photographic aid device being used in a radiographic device, the radiographic device having a radiation source and a radiation image detector for detecting a radiation image of a subject based on radiation irradiated from and transmitted through the radiation source, the photographic aid device comprising an optical camera that acquires optical images frame by frame by performing optical photography on a region including an irradiation field of radiation irradiated from the radiation source onto the subject, and outputs a dynamic image consisting of a plurality of acquired frames, wherein the method of operating the photographic aid device... Based on a timing signal sent from the radiation image detector side, a frame of the optical image acquired by the optical camera is correlated as a still image with the radiation image that the technician determines to have photographic loss. The still image is overlaid on frames of a moving image generated by capturing moving images through the optical camera and displayed on a monitor.

7. A storage medium, readable by a computer and storing an operating program that causes a photographic aid device to operate, the photographic aid device being used in a radiographic apparatus, the radiographic apparatus having a radiation source and a radiation image detector for detecting a radiation image of a subject based on radiation irradiated from and transmitted through the radiation source, the photographic aid device comprising an optical camera for acquiring optical images frame by frame by performing optical photography on an area including an irradiation field of radiation irradiated from the radiation source onto the subject, and outputting a dynamic image consisting of a plurality of acquired frames, and at least one processor, the operating program causing the processor to perform the following actions: Based on a timing signal sent from the radiation image detector side, a frame of the optical image acquired by the optical camera is correlated as a still image with the radiation image that the technician determines to have photographic loss. The still image is overlaid on frames of a moving image generated by capturing moving images through the optical camera and displayed on a monitor.

Images