Location information acquisition device, method and program, and radiographic image acquisition device

Abstract

To provide a position information acquisition device, method, and program, and a radiography apparatus, in which positions of feature points of surgical instruments, etc. within a subject can be determined in real time.SOLUTION: An image acquisition unit acquires a radiographic image set including a plurality of radiographic images, which have been generated by alternately illuminating a subject with radiation emitted from a plurality of radiation sources provided at different positions and alternately detecting the radiation transmitted through the subject using one detection unit, at a predetermined time interval. A feature point detection unit detects at least one common feature point in the subject from each of the plurality of radiographic images included in the radiographic image set. A position information derivation unit derives three-dimensional position information of the at least one feature point in the subject using a positional relationship between a position of the at least one feature point, on a detection surface of the detection unit, detected from each of the plurality of radiographic images and positions of the plurality of radiation sources.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a position information acquisition device, method, and program for acquiring three-dimensional position information of feature points in a subject, and a radiation imaging device.

Background Art

[0002] In surgery and catheter treatment, it is necessary to grasp the positional relationship between surgical instruments and human structures such as bones and blood vessels. However, conventionally, grasping the positional relationship between surgical instruments and human structures often relies on the experience and intuition of doctors, and problems such as misinsertion of surgical instruments and excessive surgical time have occurred. For this reason, during surgery, the subject is photographed by a fluoroscopic device, and the positional relationship between the surgical instrument and the human structure is grasped using the fluoroscopic image displayed on the display by the photographing. However, while the surgical instrument and the human structure have a three-dimensional positional relationship, the fluoroscopic image is a two-dimensional image. It is difficult to grasp the three-dimensional positional relationship between the surgical instrument and the human structure even by looking at the two-dimensional fluoroscopic image.

[0003] For this reason, the three-dimensional positional relationship between the surgical instrument and the human structure is grasped by fluoroscopic images from a plurality of directions obtained by photographing the subject, the patient, while changing the angle during the procedure, or by using a plurality of photographing devices simultaneously. In addition, a method of attaching a sensor to the surgical instrument to grasp the three-dimensional position of the surgical instrument has also been proposed.

[0004] However, when photographing the subject while changing the angle, it is necessary to move the photographing device during the procedure. In addition, when using a plurality of photographing devices simultaneously, although there is no need to move the photographing device, the working space for the doctor during the surgery becomes small, so there is a possibility that the procedure may be hindered. In addition, the method using a sensor requires the preparation of a sensor.

[0005] Therefore, a method has been proposed in which radiation is irradiated onto a subject from multiple radiation sources placed at intervals, thereby acquiring multiple radiation images of the subject from multiple positions, and generating a three-dimensional radiation image of the subject that can be viewed in stereoscopically from these multiple radiation images (see, for example, Patent Document 1). According to the method described in Patent Document 1, a physician can grasp the three-dimensional positional relationship between surgical instruments and the human body structure by viewing the three-dimensional radiation image in stereoscopically. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2014-226174 [Overview of the project] [Problems that the invention aims to solve]

[0007] In surgical procedures and catheter-based treatments, it is necessary to understand the positional relationship between surgical instruments and human anatomical structures in real time. However, the method described in Patent Document 1 requires processing time to generate three-dimensional radiographic images. In recent years, the resolution and density resolution of radiographic images have improved, resulting in very large amounts of data in the image data representing radiographic images. Generating three-dimensional images from such large amounts of radiographic data requires processing time. Therefore, the method described in Patent Document 1 makes it difficult to understand the position, and even the positional relationship, between surgical instruments and human anatomical structures within a patient in real time.

[0008] This disclosure is made in view of the above circumstances and aims to enable real-time tracking of the three-dimensional positions of characteristic points of surgical instruments and other objects within a patient's specimen. [Means for solving the problem]

[0009] The location information acquisition device according to this disclosure includes an image acquisition unit that acquires a set of radiation images consisting of multiple radiation images generated by alternately irradiating a subject with radiation from multiple radiation sources located at different positions and alternately detecting the radiation that has passed through the subject using a single detection unit, at predetermined time intervals. A feature point detection unit that detects at least one common feature point within a subject from each of multiple radiographic images included in a set of radiographic images, The system includes a position information derivation unit that derives three-dimensional position information of at least one feature point within a subject by using the positional relationship between the position of at least one feature point detected from each of multiple radiation images on the detection surface of a detection unit and the positions of multiple radiation sources.

[0010] "At predetermined time intervals" means, for example, at time intervals corresponding to the frame rate of a video. For example, 25-60 fps can be used as the predetermined time interval, and as a result, in this disclosure, a combination of radiation images is acquired, similar to a video. Note that all of the multiple radiation images may have the same time interval, or each of the multiple radiation images may have a different time interval.

[0011] Furthermore, the location information acquisition device according to this disclosure may further include a display control unit that displays location information on a display unit.

[0012] Furthermore, in the location information acquisition device according to this disclosure, the feature point detection unit may detect points on surgical instruments inserted into the subject as feature points.

[0013] The radiation imaging apparatus according to this disclosure comprises a plurality of radiation sources arranged at predetermined intervals, A detection unit is positioned opposite multiple radiation sources and generates a radiation image of the subject by detecting radiation emitted from each of the multiple radiation sources that has passed through the subject. A shooting control unit controls the timing of radiation emission from each of multiple radiation sources and the timing of detection of radiation that has passed through the subject by a detection unit, thereby alternately irradiating the subject with radiation from multiple radiation sources and alternately detecting the radiation that has passed through the subject by the detection unit, thereby generating a set of radiation images consisting of multiple radiation images at predetermined time intervals. This disclosure includes a location information acquisition device.

[0014] Furthermore, the radiation imaging device described herein may have two radiation sources.

[0015] Furthermore, in the radiation imaging apparatus according to this disclosure, the imaging control unit controls the detection unit to sequentially emit radiation from one of the two radiation sources at a first time interval, sequentially emit radiation from the other radiation source at a second time interval longer than the first time interval, and detect radiation at all times when radiation is emitted from both radiation sources. The image acquisition unit may acquire two radiation images as a pair of radiation images by detecting two radiation emitted temporally adjacent from two radiation sources using a detection unit.

[0016] "Greater than or equal to the first time interval" means being the same as the first time interval, or being greater than the first time interval.

[0017] The location information acquisition method described herein involves alternately irradiating a subject with radiation from multiple radiation sources located at different positions, and alternately detecting the radiation that has passed through the subject with a single detection unit. A set of radiation images, consisting of multiple radiation images, is then acquired at predetermined time intervals. From each of the multiple radiographic images included in the set of radiographic images, at least one common feature point within the subject is detected. Using the positional relationship between the positions of at least one feature point detected from each of a plurality of radiographic images on the detection surface of the detection unit and the positions of the plurality of radiation sources, three-dimensional position information of at least one feature point within the subject is derived.

[0018] Note that it may be provided as a program for causing a computer to execute the position information acquisition method according to the present disclosure.

[0019] Another position information acquisition device according to the present disclosure includes a memory that stores instructions for causing a computer to execute, a processor configured to execute the stored instructions, and the processor irradiates a subject with radiation alternately from a plurality of radiation sources arranged at different positions, and acquires, at a predetermined time interval, a set of radiographic images composed of a plurality of radiographic images generated by alternately detecting the radiation transmitted through the subject by one detection unit, detects at least one common feature point within the subject from each of the plurality of radiographic images included in the set of radiographic images, and executes a process of deriving three-dimensional position information of at least one feature point within the subject by using the positional relationship between the position of at least one feature point detected from each of the plurality of radiographic images on the detection surface of the detection unit and the positions of the plurality of radiation sources.

Advantages of the Invention

[0020] According to the present disclosure, the positions of feature points such as surgical instruments and human body structures within the subject can be grasped in real time.

Brief Description of the Drawings

[0021] [Figure 1] 1Schematic configuration diagram of a radiographic imaging device to which a position information acquisition device according to an embodiment of the present disclosure is applied [Figure 2] Schematic diagram showing the configuration of a radiation irradiation unit [Figure 3]This diagram shows the schematic configuration of a location information acquisition device realized by installing a location information acquisition program on a computer in this embodiment. [Figure 4] A diagram illustrating the timing of radiation emission from the first and second radiation sources, and the timing of radiation detection by the radiation detector. [Figure 5] A diagram showing fluoroscopic images displayed during catheter treatment. [Figure 6] Diagram showing a situation where the stent and guidewire are in different positions. [Figure 7] Diagram to explain lumbar spinal fusion surgery [Figure 8] A diagram illustrating the derivation of the three-dimensional positional information of feature points. [Figure 9] Diagram illustrating photography from two directions. [Figure 10] This diagram shows radiographic images obtained by taking images from two directions. [Figure 11] This figure shows projected images from two directions generated from a 3D image. [Figure 12] This diagram shows radiographic images obtained by taking images from two directions. [Figure 13] Diagram showing the position information screen in the case of catheter treatment. [Figure 14] Diagram showing positional information screen in the case of lumbar spinal fusion surgery. [Figure 15] Flowchart showing the process performed in this embodiment [Figure 16] A diagram illustrating the timing of radiation emission from the first and second radiation sources, and the timing of radiation detection by the radiation detector. [Modes for carrying out the invention]

[0022] Embodiments of this disclosure will be described below with reference to the drawings. Figure 1 is a schematic diagram of a radiographic imaging apparatus to which a position information acquisition device according to an embodiment of this disclosure is applied. The radiographic imaging apparatus according to this embodiment is for acquiring and displaying radiographic fluoroscopic images of a subject H as moving images when performing surgical procedures and catheter treatments on a subject H.

[0023] In this embodiment, the x-axis is set in the left-right direction in Figure 1, the y-axis in the depth direction in Figure 1, and the z-axis is set perpendicular to the plane on which the radiographic imaging device 1 shown in Figure 1 is placed.

[0024] As shown in Figure 1, the radiation imaging apparatus 1 according to this embodiment includes a C-arm 2. An imaging unit 3 is attached to one end of the C-arm 2, and a radiation irradiation unit 4 is attached to the other end so as to face the imaging unit 3.

[0025] The imaging unit 3 is equipped with a radiation detector 5, such as a flat panel detector. The radiation detector 5 corresponds to the detection unit of this disclosure. The imaging unit 3 also contains a circuit board equipped with a charge amplifier that converts the charge signal read from the radiation detector 5 into a voltage signal, a correlated double sampling circuit that samples the voltage signal output from the charge amplifier, and an AD (Analog Digital) conversion unit that converts the voltage signal into a digital signal. In this embodiment, a radiation detector 5 is used, but the device is not limited to a radiation detector 5 as long as it can detect radiation and convert it into an image. For example, a detection device such as an image intensifier can also be used.

[0026] The radiation detector 5 is capable of repeatedly recording and reading out radiation images. It may use a so-called direct-type radiation detector that directly converts radiation such as X-rays into electric charge, or it may use a so-called indirect-type radiation detector that first converts radiation into visible light and then converts that visible light into an electric charge signal. Furthermore, as a method for reading out the radiation image signal, it is desirable to use a so-called TFT (Thin Film Transistor) readout method in which the radiation image signal is read out by turning a TFT switch on and off, or a so-called optical readout method in which the radiation image signal is read out by irradiating it with reading light. However, it is not limited to these, and other methods may also be used.

[0027] Figure 2 is a schematic diagram showing the configuration of the radiation irradiation unit 4. As shown in Figure 2, the radiation irradiation unit 4 houses a first radiation source 6A and a second radiation source 6B. The first and second radiation sources 6A and 6B are arranged side by side in the depth direction (i.e., the y-axis direction) shown in Figure 1, at a predetermined interval. The first and second radiation R1 and R2 emitted from the first and second radiation sources 6A and 6B are emitted toward the imaging unit 3 from the first and second emission units 4A and 4B, respectively.

[0028] The first and second radiation sources 6A and 6B emit X-rays as radiation, and the timing of radiation emission from the first and second radiation sources 6A and 6B, as well as the timing of detection of the first and second radiation sources R1 and R2 by the radiation detector 5, are controlled by the imaging control unit 14, which will be described later. In addition, the radiation generation conditions for the first and second radiation sources 6A and 6B, namely the selection of target and filter materials, tube voltage, and irradiation time, are also controlled by the imaging control unit 14.

[0029] In this embodiment of the radiation imaging apparatus 1, the so-called SID (Source Image Distance), which is the distance between the detection surface 5A of the radiation detector 5 and the first and second radiation sources 6A and 6B of the radiation irradiation unit 4, is set to a fixed value.

[0030] In this embodiment, the C-arm 2 is held by the C-arm holder 7 so as to be movable in the direction of arrow A shown in Figure 1, allowing the angle of the imaging unit 3 and the radiation irradiation unit 4 with respect to the z direction (vertical direction) shown in Figure 1 to be changed integrally. The C-arm holder 7 also has a shaft 8, which rotatably connects the C-arm 2 to the bearing 9. As a result, the C-arm 2 is rotatable in the direction of arrow B shown in Figure 1, with the shaft 8 as the axis of rotation.

[0031] Furthermore, as shown in Figure 1, the radiographic imaging apparatus 1 of this embodiment includes a main body 10. Multiple wheels 11 are attached to the bottom of the main body 10, thereby making the radiographic imaging apparatus 1 of this embodiment movable. A support shaft 12 that extends and retracts in the z-axis direction of Figure 1 is provided at the upper part of the housing of the main body 10 in Figure 1. A bearing 9 is held at the upper part of the support shaft 12 so as to be movable in the direction of arrow C.

[0032] The radiographic imaging apparatus 1 according to this embodiment has the above configuration, which irradiates the subject H, who is lying supine on the imaging table 40, with radiation from below, and detects the radiation that has passed through the subject H with the radiation detector 5 of the imaging unit 3 to acquire a radiographic image of the subject H. Here, the C arm 2 is movable in the directions of arrows A, B and C, and the radiographic imaging apparatus 1 is movable by wheels 11. Therefore, the radiographic imaging apparatus 1 according to this embodiment is capable of imaging a desired part of the subject H, who is lying supine on the imaging table 40, from a desired direction.

[0033] Furthermore, the main unit 10 incorporates an I / F (Interface) unit 13, an image capture control unit 14, and a position information acquisition device 15 according to this embodiment.

[0034] The I / F unit 13 has the function of communicating wirelessly or via wired connection with a console and external devices (neither of which are shown) that perform overall control over the acquisition of radiographic images by the radiographic imaging device 1. In this embodiment, the radiographic imaging device 1 takes images of the subject H based on the imaging instructions received from the console via the I / F unit 13.

[0035] The imaging control unit 14 emits first and second radiation R1 and R2 from the first and second radiation sources 6A and 6B of the radiation irradiation unit 4, respectively, based on the imaging conditions associated with the imaging instruction from the console. The imaging control unit 14 also detects the first and second radiation R1 and R2 that have passed through the subject H using the radiation detector 5 of the imaging unit 3, according to the timing of the emission of the first and second radiation R1 and R2 from the first and second radiation sources 6A and 6B, and generates the first radiation image G1 and the second radiation image G2 of the subject H. The generated first and second radiation images G1 and G2 are output to the main unit 10. The timing of the emission of the first and second radiation R1 and R2 from the first and second radiation sources 6A and 6B, and the timing of the detection of the first and second radiation R1 and R2 by the radiation detector 5 will be described later.

[0036] Furthermore, a user interface 16 is provided on the upper part of the main unit 10. The user interface 16 has functions for users such as technicians and doctors who take radiographic images using the radiographic imaging device 1 to give instructions regarding the taking of radiographic images, a function to display the radiographic images acquired by the taking as radiofluoroscopic images, and a function to provide users with information regarding the taking of radiographic images. An example of the user interface 16 is a touch panel display.

[0037] Next, the location information acquisition device according to this embodiment will be described. Figure 3 is a diagram showing the schematic configuration of the location information acquisition device according to this embodiment. As shown in Figure 3, the location information acquisition device 15 is a computer, and as a standard computer configuration, it is equipped with a CPU (Central Processing Unit) 21, memory 22 and storage 23.

[0038] The location information acquisition device 15 according to this embodiment has the location information acquisition program according to this embodiment installed. The location information acquisition program is stored in a storage device of a server computer connected to the network, or in network storage, in a state that is accessible from the outside, and is downloaded to the location information acquisition device 15 via the I / F unit 13 and installed upon request. Alternatively, it is recorded on a recording medium such as a DVD (Digital Versatile Disc) or CD-ROM (Compact Disc Read Only Memory) and distributed, and then installed to the location information acquisition device 15 from that recording medium.

[0039] Storage 23 consists of a storage device such as a hard disk drive or SSD (Solid State Drive), and stores various information, including a location information acquisition program. Radiation images acquired through photography are also stored in storage 23.

[0040] Memory 22 temporarily stores programs and other data stored in storage 23 in order to have the CPU 21 execute various processes. The location information acquisition program defines the following processes to be executed by the CPU 21: an image acquisition process that acquires a set of radiation images consisting of first and second radiation images G1 and G2, acquired by the radiation image acquisition device 1 as described later, at predetermined time intervals; a feature point detection process that detects at least one common feature point within the subject H from each of the first and second radiation images G1 and G2 included in the set of radiation images; a location information derivation process that derives three-dimensional location information of at least one feature point within the subject H using the positional relationship between the position of the feature point detected from the first and second radiation images G1 and G2 on the detection surface 5A of the radiation detector 5 and the positions of the first and second radiation sources 6A and 6B; a three-dimensional information derivation process that derives three-dimensional information about the target structure within the subject H; and a display control process that displays the location information on the user interface 16.

[0041] Then, as the CPU 21 executes these processes according to the location information acquisition program, the computer functions as a location information acquisition device 15 equipped with an image acquisition unit 31, a feature point detection unit 32, a location information derivation unit 33, a 3D information derivation unit 34, and a display control unit 35.

[0042] The image acquisition unit 31 acquires a set of radiation images consisting of the first and second radiation images G1 and G2 of the subject H, which are generated by the imaging control unit 14 controlling the first and second radiation sources 6A and 6B and the radiation detector 5. The timing of the emission of the first and second radiation R1 and R2 from the first and second radiation sources 6A and 6B, and the timing of the detection of the first and second radiation R1 and R2 by the radiation detector 5 will be described below. Figure 4 is a diagram illustrating the timing of the emission of the first and second radiation R1 and R2 from the first and second radiation sources 6A and 6B, and the timing of the detection of the first and second radiation R1 and R2 by the radiation detector 5.

[0043] Figure 4 shows the timing T1 for the emission of the first radiation R1 from the first radiation source 6A, the timing T2 for the emission of the second radiation R2 from the second radiation source 6B, and the timing T3 for the detection of the first and second radiation R1 and R2 by the radiation detector 5. T4 is the timing for the derivation of position information, which will be described later.

[0044] As shown in Figure 4, when the first radiation R1 is emitted from the first radiation source 6A, the radiation detector 5 detects the first radiation R1 that has passed through the subject H and generates the first radiation image G1. When the radiation detector 5 generates the first radiation image G1, the second radiation R2 is emitted from the second radiation source 6B, and the radiation detector 5 detects the second radiation R2 that has passed through the subject H and generates the second radiation image G2. When the radiation detector 5 generates the second radiation image G2, the next first radiation R1 is emitted from the first radiation source 6A, and the radiation detector 5 detects the next first radiation R1 that has passed through the subject H and generates the next first radiation image G1. By repeating this process, the first radiation image G1 and the second radiation image G2 are acquired alternately and repeatedly. The image acquisition unit 31 acquires the temporally adjacent first and second radiation images G1 and G2 as a pair of radiation images.

[0045] The time interval for generating the first and second radiation images G1 and G2 by the radiation detector 5 is 25 to 60 fps, for example, 30 fps. If the time interval for generating the first and second radiation images G1 and G2 is set to 30 fps, the timing of emission of the first and second radiation R1 and R2 from the first and second radiation sources 6A and 6B, respectively, will be 15 fps.

[0046] Here, we will describe the procedure for performing catheter treatment of an abdominal aortic aneurysm on subject H using the radiographic imaging device 1 according to this embodiment. Figure 5 shows a radiographic image displayed on the user interface 16 during catheter treatment. As shown in Figure 5, during catheter treatment of an abdominal aortic aneurysm, a bifurcated stent 51 inserted on a guidewire 52 is inserted into the aorta 50 from an artery in the groin of one leg, and one branch 51A of the stent 51 is widened by the guidewire 52. Subsequently, another guidewire 53 is inserted into the aorta 50 from an artery in the groin of the other leg, and the guidewire 53 is passed through the other branch 51B of the stent 51 to widen the branch 51B of the stent 51. In this embodiment, the first radiographic image G1 or the second radiographic image G2 of the abdominal aortic aneurysm of subject H is displayed on the user interface 16 as a moving radiographic image. The user performs the task of passing the guidewire 53 through the branch 51B of the stent 51 while viewing the fluoroscopic image displayed on the user interface 16.

[0047] Here, the diameter of the branch 51B of the stent 51 is small, and the fluoroscopic image displayed on the user interface 16 is a two-dimensional image. Therefore, the three-dimensional positional relationship between the end of the branch 51B of the stent 51 and the tip 53A of the guidewire 53 is difficult to discern. For example, in the fluoroscopic image shown in Figure 5, it appears that the guidewire 53 is inserted into the branch 51B of the stent 51. However, in reality, as shown in Figure 6, it is possible that the guidewire 53 is not inserted into the branch 51B.

[0048] Furthermore, when performing lumbar spinal fusion surgery, a frontal radiograph of subject H is taken to determine the screw insertion position, and while displaying the lateral radiograph of subject H shown in Figure 7 as a moving image, the screw 55 is inserted into the lumbar vertebra 56 while confirming the depth and angle. However, since radiographs are two-dimensional images, it is difficult to determine the insertion position and angle of the screw 55, which can lead to misinsertion. This embodiment was made to solve these problems.

[0049] The feature point detection unit 32 detects at least one common feature point within the subject H from each of the first and second radiographic images G1 and G2 included in the set of radiographic images. For example, in the case of catheter treatment, the tip 53A of the guidewire 53 included in each of the first and second radiographic images G1 and G2 is detected as a feature point. In the case of lumbar spinal fusion surgery, the tip 55A and the rear end 55B of the screw 55 included in each of the first and second radiographic images G1 and G2 are detected as feature points. In this embodiment, the feature point detection unit 32 has a trained model that has been trained to detect feature points included in the first and second radiographic images G1 and G2.

[0050] Note that feature points include not only a single pixel but also a region with a certain area consisting of multiple pixels. For example, the tip 53A of the guide wire 53, the tip 55A of the screw 55, and the rear end 55B of the screw 55 all have a certain area, but in this embodiment, they are included as feature points.

[0051] The trained model consists of a neural network that has undergone deep learning to detect feature points contained in the first and second radiation images G1 and G2. The trained model is generated by training the neural network using a large number of images with known feature points as training data. As a result, when the first and second radiation images G1 and G2 are input to the feature point detection unit 32, it detects common feature points from the first and second radiation images G1 and G2 and outputs the two-dimensional position coordinates of the detected feature points.

[0052] The trained model may consist of a deep learning neural network, or, for example, a support vector machine (SVM), a convolutional neural network (CNN), or a recurrent neural network (RNN).

[0053] Furthermore, the feature point detection unit 32 is not limited to detecting feature points using a trained model. For example, any method can be used to detect feature points, such as a method that detects feature points included in the first and second radiation images G1 and G2 by template matching.

[0054] The position information derivation unit 33 derives three-dimensional position information of feature points within the subject H using the positional relationship between the positions of feature points detected from the first and second radiation images G1 and G2 on the detection surface 5A of the radiation detector 5 and the positions of the first and second radiation sources 6A and 6B. Figure 8 is a diagram illustrating the derivation of three-dimensional position information of feature points. The position information derivation unit 33 acquires information on the source position S1(sx1,sy1,sz1) of the first radiation source 6A, the source position S2(sx2,sy2,sz2) of the second radiation source 6B, the position D1(dx1,dy1,dz1) of the feature points detected in the first radiation image G1, and the position D2(dx2,dy2,dz2) of the feature points detected in the second radiation image G2, as shown in Figure 8.

[0055] The three-dimensional coordinates (sx1, sy1, sz1) of source position S1 and the three-dimensional coordinates (sx2, sy2, sz2) of source position S2 can be derived based on the positional relationship between the origin and the first and second radiation sources 6A and 6B when a coordinate system is set with the origin at an arbitrary position on the C-arm 2 of the radiation imaging device 1. For example, in this embodiment, a coordinate system can be set with the origin at a point that bisects the line connecting the centers of the first and second emission sections 4A and 4B in the radiation irradiation section 4.

[0056] On the other hand, since the SID is known, the three-dimensional coordinates of the center position of the detection surface 5A of the radiation detector 5 can be derived with respect to the above-mentioned origin. Furthermore, using the three-dimensional coordinates of the center position of the detection surface 5A of the radiation detector 5, the three-dimensional coordinates of the feature point positions D1 and D2 can be derived from the two-dimensional position coordinates of the feature points in the first and second radiation images G1 and G2 detected by the feature point detection unit 32.

[0057] The position information derivation unit 33 sets a straight line L1 connecting the source position S1 and the feature point position D1, and a straight line L2 connecting the source position S2 and the feature point position D2. When any point P1 on the straight line L1 and any point P2 on the straight line L2 are expressed using the source positions S1, S2 and the feature point positions D1, D2, the following equation (1) is obtained. In equation (1), t and s are parameters, respectively.

[0058] P1 = (1-t)·S1 + t·D1 P2 = (1-s)·S2 + s·D2 (1)

[0059] Ideally, the feature points within the subject H detected in the first and second radiation images G1 and G2 will be located at the intersection in three-dimensional space of point P1 on line L1 and point P2 on line L2. Therefore, in this embodiment, the position information derivation unit 33 derives the three-dimensional coordinates of the point where the distance between point P1 and point P2 is minimized as the three-dimensional position information P0(x0,y0,z0) of the feature points detected in the first and second radiation images G1 and G2, using the following equation (2).

[0060] P0 = min(P1 - P2) 2 (2)

[0061] Furthermore, when the image acquisition unit 31 acquires a set of radiation images consisting of the first and second radiation images G1 and G2 in succession, the position information derivation unit 33 derives position information P0 using the first and second radiation images G1 and G2 included in the acquired set of radiation images. Therefore, the timing at which the position information derivation unit 33 derives position information P0 is the timing T4 shown in Figure 4.

[0062] The 3D information extraction unit 34 takes images of the subject H from two directions and extracts 3D information about the target structure to be targeted during the procedure, which is included in the subject H. For example, in the case of catheter treatment for an abdominal aortic aneurysm, the stent 51 is first inserted, then the branch 51A is expanded, and then the guidewire 53 is inserted into the branch 51B. For this reason, the 3D information extraction unit 34 extracts the center position of the end of branch 51B of the stent 51 as 3D information about the target structure. Figure 9 is a diagram illustrating the imaging of the subject H from two directions, and Figure 10 is a diagram showing the radiographic images obtained by imaging from two directions.

[0063] When the C-arm 2 moves to the position shown in Figure 1, the imaging control unit 14 irradiates the subject H with radiation from the direction of arrow E1 shown in Figure 9, according to the user's instructions, thereby acquiring the radiation image GE1 shown in Figure 10. Furthermore, when the radiation irradiation unit 4 is moved to the right side of the subject H in Figure 1, and radiation is irradiated onto the subject H from the direction of arrow E2, the radiation image GE2 shown in Figure 10 is acquired. Radiation images GE1 and GE2 include images of the stent 51. The coordinates of the center positions of radiation images GE1 and GE2 are known because they coincide with the coordinates of the center position of the detection surface 5A of the radiation detector 5. Therefore, the 3D information derivation unit 34 derives the 3D coordinates of the center position of the end of the branch 51B into which the guide wire of the stent 51 should be inserted in radiation images GE1 and GE2, in the same coordinate system as when feature points are detected, as 3D information of the target structure.

[0064] Here, the coordinate system is not limited to the same one used when the feature points were detected. For example, a coordinate system may be set with the center position of the end of branch 51B of stent 51 as the origin.

[0065] Alternatively, the 3D information derivation unit 34 may have the radiographic imaging device 1 perform tomosynthesis imaging to generate a 3D image of the target area of ​​the subject H, and then derive 3D information of the target structure from the 3D image acquired by tomosynthesis imaging.

[0066] In tomosynthesis imaging, the C-arm 2 is rotated in the direction of arrow A, and radiation is emitted from one of the first and second radiation sources 6A and 6B (in this case, the first radiation source 6A) from multiple source positions to image the subject H, thereby acquiring multiple projection images. The 3D information derivation unit 34 then reconstructs the multiple projection images using a back projection method such as simple back projection or filtered back projection to generate tomographic images for each of the multiple tomographic planes of the subject H. Finally, a 3D image is generated from the multiple tomographic images.

[0067] The 3D information derivation unit 34 performs a coordinate transformation to match the coordinate system of the 3D image with the coordinate system of the feature points, and derives the 3D coordinates of the center position of the end of branch 51B of the stent 51 as 3D information of the target structure. In this case, a coordinate system may be set with the center position of the end of branch 51B of the stent 51 as the origin.

[0068] The 3D information derivation unit 34 may also derive 3D information from 3D images previously acquired by a CT (Computed Tomography) device and an MRI (Magnetic Resonance Imaging) device, etc. In this case, similar to the 3D images acquired by tomosynthesis imaging described above, a coordinate transformation should be performed to match the coordinate system of the previously acquired 3D image with the coordinate system of the feature points, and the 3D coordinates of the center position of the end of branch 51B of the stent 51 should be derived as the 3D information of the target structure. In this case as well, a coordinate system may be set with the center position of the end of branch 51B of the stent 51 as the origin.

[0069] On the other hand, when performing lumbar spinal fusion surgery, the 3D information output unit 34 outputs the 3D coordinates of the insertion and arrival positions in the lumbar spine, which are predetermined, as 3D information of the target structure, from the 3D image of the subject H acquired by a CT or MRI device before the procedure. In this case, the 3D information output unit 34 generates projected images GP1 and GP2 by projecting the 3D image in the directions of arrows E1 and E2, respectively, as shown in Figure 9. Figure 11 shows the projected images in the two directions. As shown in Figure 11, projected image GP1 is a frontal view of the lumbar spine of subject H, and projected image GP2 is a lateral view of the lumbar spine of subject H. Here, the insertion and arrival positions of the screw 55 are predetermined and set on the 3D image based on preoperative studies. For this reason, the insertion position PS and arrival position PE are specified in projected images GP1 and GP2.

[0070] Furthermore, the 3D information derivation unit 34 photographs the subject H from the two directions shown in Figure 9 to acquire the radiation images GE11 and GE12 shown in Figure 12. Then, the coordinate systems of the radiation images GE11 and GE12 are matched with the coordinate systems of the projected images GP1 and GP2 to identify the insertion position PS1 and the arrival position PE1 in the radiation images GE11 and GE12. In this case, it is preferable, but not limited to, that the coordinate system to be matched be one with the insertion position PS in the projected images GP1 and GP2 as the origin. The coordinate systems of the radiation images GE11 and GE12 may be matched with a coordinate system with any point on the projected images GP1 and GP2 as the origin, or the coordinate systems of the projected images GP1 and GP2 may be matched with the coordinate systems of the radiation images GE11 and GE12.

[0071] The display control unit 35 displays the position information P0 on the user interface 16. In this case, the display control unit 35 also uses the 3D information of the target structure derived by the 3D information derivation unit 34 to display the position information P0. Figure 13 is a diagram showing the position information screen when performing catheter treatment. As shown in Figure 13, the position information screen 60 has a display area 61 for radiographic images and a display area 62 for position information P0. The first radiographic image G1 is sequentially displayed as a radiographic image in the display area 61. Therefore, the radiographic image is displayed as a moving image in the display area 61. Alternatively, the second radiographic image G2 may be sequentially displayed as a radiographic image in the display area 61.

[0072] Here, the 3D information derivation unit 34 derives the 3D coordinates of the center position of the branch 51B of the stent 51 as 3D information of the target structure, and the position information derivation unit 33 derives the position information P0 of the tip 53A of the guide wire 53. The diameter of the branch 51B of the stent 51 is known. Therefore, the display control unit 35 generates a stent image GT0 that schematically represents the shape of the branch 51B of the stent 51 and displays it in the position information display area 62. The stent image GT0 is an image of the end of the branch 51B of the stent 51 viewed in the direction of its central axis. Furthermore, the display control unit 35 displays a mark M0 representing the position of the tip 53A of the guide wire 53 in the display area 62. In this process, the display control unit 35 matches the positional relationship between the mark M0 and the stent image GT0 with the positional relationship between the tip 53A of the guidewire 53 and the center position of the branch 51B of the stent 51, which is derived by the 3D information derivation unit 34. Here, the position of the tip 53A of the guidewire 53 is obtained in 3D coordinates. Therefore, the mark M0 represents the position of the tip 53A of the guidewire 53 in an image of the branch 51B of the stent 51 viewed in the direction of its central axis.

[0073] The user inserts the guidewire 53 into the subject H's body while viewing the position information screen 60, ensuring that the mark M0 is positioned inside the circle representing the end of branch 51B in the stent image GT0. Here, the positional relationship between the stent image GT0 and the mark M0 shown in Figure 13 indicates that the tip 53A of the guidewire 53 is away from the end of branch 51B of the stent 51. The user can adjust the position of the guidewire 53 to be inserted into the subject H while viewing the position information screen 60, so that the mark M0 is positioned inside the stent image GT0. This reduces the chance of errors in inserting the guidewire 53 into the stent 51, as shown in Figure 6 above.

[0074] The display control unit 35 may also notify the user interface 16 when the guide wire 53 has reached the center of the branch 51B of the stent 51 and has been inserted into the branch 51B. The notification may be by text display, by voice, or by both display and voice.

[0075] Furthermore, the sound may change depending on the distance between the tip 53A of the guide wire 53 and the center position of the branch 51B. For example, the sound may be an intermittent beep, and the interval between beeps may decrease as the tip 53A of the guide wire 53 approaches the center position of the branch 51B. Also, the sound may change when the tip 53A of the guide wire 53 is inserted into the branch 51B.

[0076] Furthermore, if the tip 53A of the guide wire 53 passes through the end of the branch 51B without being inserted into the branch 51B, or if the tip 53A of the guide wire 53 is more than a predetermined threshold away from the center of the branch 51B, a warning to that effect may be issued in the user interface 16.

[0077] On the other hand, Figure 14 shows the position information screen when performing lumbar spinal fusion surgery. As shown in Figure 14, the position information screen 70 has a display area 71 for fluoroscopic images and a display area 72 for position information. The display area 71 sequentially displays the first radiographic image G1, which is a lateral view of the lumbar spine. Therefore, the radiographic images are displayed as moving images in the display area 71. The first radiographic image G1 includes an image of the screw 55. Alternatively, the display area 71 may sequentially display the second radiographic image G2 as a radiographic image.

[0078] Here, the 3D information derivation unit 34 derives the 3D coordinates of the insertion position PS and arrival position PE of the screw 55 in the lumbar spine as 3D information of the target structure. The position information derivation unit 33 derives the position information P0 of the tip 55A and rear end 55B of the screw 55. Therefore, the display control unit 35 generates a tomographic image GD0 of the lumbar spine into which the screw 55 is inserted using a 3D image of the subject H acquired in advance, and displays the generated tomographic image GD0 in the position information display area 72. The tomographic image GD0 of the lumbar spine displayed in the display area 72 represents an axial section.

[0079] Furthermore, the display control unit 35 displays a mark M1, which is the screw 55 derived by the position information derivation unit 33 projected onto the tomographic plane of the tomographic image GD0, in the position information display area 72. At this time, the display control unit 35 matches the positional relationship between the tip and trailing end of the mark M1 and the insertion position PS and arrival position PE on the tomographic image GD0 with the positional relationship between the tip 55A and trailing end 55B of the screw 55 and the insertion position PS and arrival position PE derived by the 3D information derivation unit 34. In addition, until the screw 55 reaches the insertion position PS, the display control unit 35 displays the remaining distance from the tip 55A of the screw 55 to the insertion position PS, derived by the position information derivation unit 33, in the information display area 74. In this embodiment, since a coordinate system with the insertion position PS as the origin is also set for the radiographic images G1 and G2, the distance from the origin to the current position of the tip 55A of the screw 55 can be derived as the remaining distance from the tip 55A of the screw 55 to the insertion position PS.

[0080] Furthermore, the display control unit 35 derives the angle (referred to as the first angle) of the screw 55's axis relative to the axial cross-section from the position of the tip 55A and the position of the rear end 55B of the screw 55, which are derived by the position information derivation unit 33. It also derives the angle at which the screw 55 should be inserted (referred to as the second angle) from the insertion position PS and the destination position PE, which are derived by the 3D information derivation unit 34. Then, it derives the difference between the first angle and the second angle and displays the derived angle in the information display area 74. In Figure 14, it is shown that the remaining distance is 10 mm and the angle is 0 degrees. An angle of 0 degrees means that the angle at which the screw 55 is inserted matches the angle between the insertion position PS and the destination position PE. After the screw 55 has been inserted into the lumbar vertebrae from the insertion position PS, the remaining distance from the tip 55A of the screw 55 to the destination position PE should be displayed in the information display area 74.

[0081] Furthermore, the display control unit 35 may issue a warning if the tip 55A of the screw 55 is located at a predetermined threshold distance from the insertion position PS. Also, the display control unit 35 may issue a warning if the angle of the screw 55 exceeds a predetermined threshold (for example, 10 degrees).

[0082] The user can insert the screw 55 into the body of subject H so that it is inserted into the lumbar spine from the insertion point PS, while viewing the tomographic image GD0, mark M1, and information display area 74. Furthermore, the user can insert the screw 55 into the lumbar spine of subject H so that it correctly reaches the target position PE.

[0083] In addition, even in the case of lumbar spinal fusion surgery, the display control unit 35 may also notify the user interface 16 when the tip 55A of the screw 55 reaches the insertion position PS and when the tip 55A of the screw 55 reaches the target position PE. Furthermore, notification may also be given when the angle of the screw 55 matches the angle at which the screw 55 should be inserted. The notification may be given by text display, by voice, or by both display and voice.

[0084] Furthermore, the sound may change depending on the distance between the tip 55A of the screw 55 and the insertion position PS and the destination position PE. For example, the sound may be a beep sound that is output intermittently, and the interval between beeps may be shortened as the tip 55A of the screw 55 approaches the insertion position PS and the destination position PE. Also, the sound may be changed when the tip 55A of the screw 55 reaches the insertion position PS and the destination position PE.

[0085] Next, the processing performed in this embodiment will be described. Figure 15 is a flowchart showing the processing performed in this embodiment. It is assumed that the 3D information of the target structure has been previously derived by the 3D information derivation unit 34 and stored in the storage 23.

[0086] Processing begins when the user issues an instruction to start imaging from the user interface 16, and the image acquisition unit 31 acquires a pair of first radiation images G1 and second radiation images G2 (acquisition of radiation image pair; step ST1). Once the pair of first radiation images G1 and second radiation images G2 is acquired, the feature point detection unit 32 detects at least one common feature point from the first and second radiation images G1 and G2 (step ST2). Next, the position information derivation unit 33 uses the positional relationship between the position of at least one feature point detected from each of the first and second radiation images G1 and G2 on the detection surface 5A of the radiation detector 5 and the positions of the first and second radiation sources 6A and 6B to derive three-dimensional positional information of at least one feature point within the subject H (step ST3).

[0087] Furthermore, the display control unit 35 displays the location information screen on the user interface 16 (step ST4) and returns to step ST1. The processing from step ST1 to step ST4 is repeated until an instruction to terminate processing is given.

[0088] In this embodiment, at least one common feature point within the subject H is detected from each of the first and second radiation images G1 and G2. The positional relationship between the position of the at least one feature point detected from each of the first and second radiation images G1 and G2 on the detection surface 5A of the radiation detector 5 and the positions of the first and second radiation sources 6A and 6B is used to derive three-dimensional positional information of at least one feature point within the subject H. Therefore, compared to generating a three-dimensional image from multiple radiation images, three-dimensional positional information of the feature point can be obtained with less computation. Accordingly, according to this embodiment, the three-dimensional position of feature points such as surgical instruments within the subject H can be grasped in real time.

[0089] In the above embodiment, the first radiation image G1 and the second radiation image G2 are acquired alternately, but the system is not limited to this. As shown in Figure 16, the second radiation image G2 may be acquired once every few frames of the first radiation image G1. In Figure 16, the second radiation image G2 is acquired once while the first radiation image G1 is acquired for four frames. In this case, the derivation of position information is performed once while the first radiation image G1 is acquired for four frames.

[0090] Furthermore, in the above embodiment, when performing catheter treatment, the 3D information output unit 34 outputs the central position of the branch 51B of the stent 51 as 3D information of the target structure, but it is not limited to this. The feature point detection unit 32 may detect the central position of the branch 51B of the stent 51 from the first and second radiographic images G1 and G2 as a feature point different from the tip 53A of the guidewire 53, and the position information output unit 33 may output position information of the central position of the branch 51B.

[0091] Furthermore, in the above embodiment, the radiation is not particularly limited, and in addition to X-rays, alpha rays or gamma rays, etc., can be applied.

[0092] Furthermore, while the above embodiments apply the position information acquisition device and radiographic imaging device according to this disclosure when performing catheter treatment and lumbar spine fusion surgery, the disclosure is not limited to these cases. This disclosure can be applied to any procedure that uses radiographic imaging.

[0093] Furthermore, in the above embodiment, the first and second radiation sources 6A and 6B are arranged in the y-axis direction as shown in Figure 1 in the radiation irradiation unit 4, but the first and second radiation sources 6A and 6B may be arranged in the x-axis direction.

[0094] Furthermore, although the above embodiment shows that the radiation irradiation unit 4 has two radiation sources 6A and 6B, it is not limited to this. It may have three or more radiation sources. In this case, position information can be derived using multiple radiation images obtained by irradiating the subject H with radiation from three or more radiation sources. Specifically, position information can be derived using a combination of two radiation images generated by radiation emitted from two of the three or more radiation sources.

[0095] Furthermore, in the above embodiment, the hardware structure of the Processing Unit, which executes various processes such as the image acquisition unit 31, the feature point detection unit 32, the position information derivation unit 33, the 3D information derivation unit 34, and the display control unit 35, can be the various processors shown below. As mentioned above, these various processors include a CPU, which is a general-purpose processor that executes software (programs) and functions as various processing units, as well as a Programmable Logic Device (PLD), which is a processor whose circuit configuration can be changed after manufacturing, such as an FPGA (Field Programmable Gate Array), and a dedicated electrical circuit, which is a processor with a circuit configuration specifically designed to execute a particular process, such as an ASIC (Application Specific Integrated Circuit).

[0096] A single processing unit may consist of one of these various processors, or it may consist of a combination of two or more processors of the same or different types (for example, a combination of multiple FPGAs or a combination of a CPU and an FPGA). Alternatively, multiple processing units may be composed of a single processor.

[0097] Examples of configuring multiple processing units with a single processor include, firstly, a configuration where one or more CPUs and software combine to form a single processor, as exemplified by client and server computers, and this processor functions as multiple processing units. Secondly, a configuration using a processor that realizes the functions of the entire system, including multiple processing units, on a single IC (Integrated Circuit) chip, as exemplified by System-on-a-Chip (SoC). Thus, various processing units are configured, in terms of hardware structure, using one or more of the above-mentioned processors.

[0098] Furthermore, the hardware structure of these various processors can more specifically utilize electrical circuits (Circuitry) that combine circuit elements such as semiconductor elements. The following are additional notes to this disclosure. (Additional note 1) An image acquisition unit acquires a set of radiation images, consisting of multiple radiation images generated by alternately irradiating a subject with radiation from multiple radiation sources positioned at different locations and alternately detecting the radiation that has passed through the subject using a single detection unit, at predetermined time intervals. A feature point detection unit detects at least one common feature point within the subject from each of the multiple radiation images included in the set of radiation images, A position information acquisition device comprising a position information derivation unit that derives three-dimensional position information of the at least one feature point within the subject by using the positional relationship between the position of the at least one feature point detected from each of the plurality of radiation images on the detection surface of the detection unit and the positions of the plurality of radiation sources. (Additional note 2) The location information acquisition device according to Appendix 1, further comprising a display control unit that displays the location information on a display unit. (Additional note 3) The position information acquisition device according to appendix 1 or 2, wherein the feature point detection unit detects points on surgical instruments inserted into the subject as feature points. (Additional note 4) Multiple radiation sources arranged at predetermined intervals, A detection unit is positioned opposite the plurality of radiation sources and generates a radiation image of the subject by detecting radiation emitted from each of the plurality of radiation sources that has passed through the subject, A shooting control unit controls the timing of radiation emission from each of the plurality of radiation sources and the timing of detection of radiation that has passed through the subject by the detection unit, thereby alternately irradiating the subject with radiation from the plurality of radiation sources and alternately detecting the radiation that has passed through the subject by the detection unit, thereby generating a set of radiation images consisting of a plurality of radiation images at predetermined time intervals. A radiographic imaging apparatus equipped with a position information acquisition device as described in any one of the appendices 1 to 3. (Additional note 5) The radiation imaging apparatus described in Appendix 4, wherein there are two radiation sources. (Additional note 6) The imaging control unit controls the detection unit to sequentially emit radiation from one of the two radiation sources at a first time interval, sequentially emit radiation from the other radiation source at a second time interval longer than the first time interval, and detect the radiation at all times when the radiation is emitted from the two radiation sources. The radiation image acquisition apparatus according to Appendix 5, wherein the image acquisition unit acquires two radiation images generated by detecting two radiation emitted adjacent to each other in time from the two radiation sources using the detection unit, as a pair of radiation images. (Additional note 7) A set of radiation images, consisting of multiple radiation images generated by alternately irradiating a subject with radiation from multiple radiation sources positioned at different locations and alternately detecting the radiation that has passed through the subject using a single detection unit, is acquired at predetermined time intervals. From each of the plurality of radiographic images included in the set of radiographic images, at least one common feature point is detected within the subject. A method for acquiring positional information, which derives three-dimensional positional information of the at least one feature point within the subject by using the positional relationship between the position of the at least one feature point detected from each of the plurality of radiation images on the detection surface of the detection unit and the positions of the plurality of radiation sources. (Additional note 8) A procedure for acquiring a set of radiation images, consisting of multiple radiation images generated by alternately irradiating a subject with radiation from multiple radiation sources positioned at different locations and alternately detecting the radiation that has passed through the subject with a single detection unit, at predetermined time intervals, and A procedure for detecting at least one common feature point within the subject from each of the plurality of radiographic images included in the set of radiographic images, A location information acquisition program that causes a computer to perform a procedure for deriving three-dimensional location information of the at least one feature point in the subject, using the positional relationship between the position of the at least one feature point detected from each of the plurality of radiation images on the detection surface of the detection unit and the positions of the plurality of radiation sources. [Explanation of Symbols]

[0099] 1. Radiation imaging device 2 C-arm 3. Photography Department 4. Radiation irradiation area 4A,4B Output section 5. Radiation detector 5A Detection surface 6A First radiation source 6B Second radiation source 7 C-arm holding part 8. Shaft section 9 bearings 10 Main body 11 wheels 12 Spindle 13 I / F section 14. Image capture control unit 15 Location information acquisition device 16 User Interface 21 CPU 22 memory 23 Storage 31 Image acquisition unit 32 Feature Point Detection Unit 33 Location information derivation unit 34 3D information derivation unit 35 Display Control Unit 40 shooting platform 50 Aorta 51 Stent 52, 53 Guide wires 53A Guide wire tip 55 Screw 55A Screw tip 55B Screw rear end 56 Lumbar vertebrae 60,70 Location information screen 61,71 Display area of ​​radiographic fluoroscopy images 62,72 Location information display area 74 Information display area D1, D2: Location of feature points in the first and second radiographic images. G1 First radiographic image G2 Second radiographic image GD0 fault image GE1, GE2, GE11, GE12 Radiation Images GP1, GP2 Projection Images GT0 stent image H Subject M0, M1 Mark PS insertion position PE reached position P0 Feature Point Location R1, R2 radiation S1, S2 Location of radiation source T1-T4 Timing

Claims

1. Two radiation sources arranged side by side at predetermined intervals, A detection unit is positioned opposite the two radiation sources and generates a radiation image of the subject by detecting radiation emitted from each of the two radiation sources and transmitted through the subject. A shooting control unit generates a radiation image of a subject by controlling the timing of radiation emission from each of the two radiation sources and the timing of detection of radiation that has passed through the subject by the detection unit, so as to sequentially emit radiation from one of the two radiation sources at a first time interval, sequentially emit radiation from the other radiation source at a second time interval longer than the first time interval, and detect the radiation at all times when the radiation is emitted from the two radiation sources. An image acquisition unit acquires a set of radiation images consisting of two radiation images including the target structure of the subject, which are generated by detecting two radiations emitted temporally adjacent from the two radiation sources using the detection unit. A feature point detection unit detects at least one common feature point, which is a point on a surgical instrument inserted into the subject, from each of the two radiographic images included in the set of radiographic images. A position information derivation unit that derives three-dimensional position information of the at least one feature point within the subject using the positional relationship between the position of the at least one feature point detected from each of the two radiation images on the detection surface of the detection unit and the positions of the two radiation sources, A three-dimensional information derivation unit that uses a radiographic image obtained by photographing the subject from the front and a radiographic image obtained by photographing from the side perpendicular to the front to derive three-dimensional information representing the three-dimensional position of at least one target point in the target structure within the subject, A display control unit that displays a position information display screen on a display that shows the positional relationship between the target point and the feature point on a common coordinate system between the target point and the feature point, based on the position information and the three-dimensional information, Equipped with, The target structure is a stent inserted into the blood vessel of the subject, the target point is the center of the end of the stent, the surgical instrument is a guide wire for expanding the stent, and the characteristic point is the tip of the guide wire. The aforementioned location information display screen includes a radiation image display area and a location information display area, The display control unit displays one of the two radiation images included in the set of radiation images in the radiation image display area, and displays an image schematically representing the target structure corresponding to the imaging from the direction of the central axis of the target structure, which is the stent, and marks representing the feature points in the position information display area based on the positional relationship of the position information and the three-dimensional information, in a radiation image acquisition device.

2. Two radiation sources arranged side by side at predetermined intervals, A detection unit is positioned opposite the two radiation sources and generates a radiation image of the subject by detecting radiation emitted from each of the two radiation sources and transmitted through the subject. A shooting control unit generates a radiation image of a subject by controlling the timing of radiation emission from each of the two radiation sources and the timing of detection of radiation that has passed through the subject by the detection unit, so as to sequentially emit radiation from one of the two radiation sources at a first time interval, sequentially emit radiation from the other radiation source at a second time interval longer than the first time interval, and detect the radiation at all times when the radiation is emitted from the two radiation sources. An image acquisition unit acquires a set of radiation images consisting of two radiation images including the target structure of the subject, which are generated by detecting two radiations emitted temporally adjacent from the two radiation sources using the detection unit. A feature point detection unit detects at least one common feature point, which is a point on a surgical instrument inserted into the subject, from each of the two radiographic images included in the set of radiographic images. A position information derivation unit that derives three-dimensional position information of the at least one feature point within the subject using the positional relationship between the position of the at least one feature point detected from each of the two radiation images on the detection surface of the detection unit and the positions of the two radiation sources, A three-dimensional information derivation unit that uses a radiographic image obtained by photographing the subject from the front and a radiographic image obtained by photographing from the side perpendicular to the front to derive three-dimensional information representing the three-dimensional position of at least one target point in the target structure within the subject, A display control unit that displays a position information display screen on a display that shows the positional relationship between the target point and the feature point on a common coordinate system between the target point and the feature point, based on the position information and the three-dimensional information, Equipped with, The target structure is the lumbar vertebra of the subject, the target point is at least one of the insertion position and the destination position of the screw inserted into the lumbar vertebra, the surgical instrument is the screw, and the characteristic points are the tip and posterior end of the screw. The aforementioned location information display screen includes a radiation image display area and a location information display area, A radiation image acquisition apparatus comprising: a display control unit that displays one of the two radiation images included in the set of radiation images in the radiation image display area, and a tomographic image of the target structure corresponding to an image taken from a direction different from the shooting direction of the one radiation image, a mark representing the target point, and a mark representing the feature point, in the position information display area based on the positional relationship of the position information and the three-dimensional information.

3. Two radiation sources arranged side by side at predetermined intervals, A detection unit is positioned opposite the two radiation sources and generates a radiation image of the subject by detecting radiation emitted from each of the two radiation sources and transmitted through the subject. A shooting control unit generates a radiation image of a subject by controlling the timing of radiation emission from each of the two radiation sources and the timing of detection of radiation that has passed through the subject by the detection unit, so as to sequentially emit radiation from one of the two radiation sources at a first time interval, sequentially emit radiation from the other radiation source at a second time interval longer than the first time interval, and detect the radiation at all times when the radiation is emitted from the two radiation sources. A radiation imaging apparatus comprising: an image acquisition unit that acquires a set of radiation images consisting of two radiation images including the target structure of the subject, generated by detecting two radiations emitted temporally adjacent from the two radiation sources using the detection unit; and a radiation imaging method in which the apparatus acquires a radiation image. The computer detects from each of the two radiographic images included in the set of radiographic images at least one common feature point, which is a point on a surgical instrument inserted into the subject, Using the positional relationship between the position of the at least one feature point detected from each of the two radiation images on the detection surface of the detection unit and the positions of the two radiation sources, three-dimensional positional information of the at least one feature point within the subject is derived. Using the radiographic image obtained by photographing the subject from the front and the radiographic image obtained by photographing from the side perpendicular to the front, three-dimensional information representing the three-dimensional position of at least one target point in the target structure within the subject is derived. A position information display screen that shows the positional relationship between the target point and the feature point on a common coordinate system between the target point and the feature point based on the position information and the three-dimensional information, wherein the position information display screen, which includes a radiographic image display area and a position information display area, is displayed on a display, the target structure is a stent inserted into the blood vessel of the subject, the target point is the center position of the end of the stent, the surgical instrument is a guide wire for expanding the stent, and the feature point is the tip of the guide wire. A method for capturing radiographic images, comprising: displaying one of the two radiographic images included in the set of radiographic images in the radiographic image display area; and displaying an image schematically representing the target structure corresponding to imaging from the direction of the central axis of the target structure, which is the stent, and marks representing the feature points, in the position information display area based on the positional relationship of the positional information and the three-dimensional information.

4. Two radiation sources arranged side by side at predetermined intervals, A detection unit is positioned opposite the two radiation sources and generates a radiation image of the subject by detecting radiation emitted from each of the two radiation sources and transmitted through the subject. A shooting control unit generates a radiation image of a subject by controlling the timing of radiation emission from each of the two radiation sources and the timing of detection of radiation that has passed through the subject by the detection unit, so as to sequentially emit radiation from one of the two radiation sources at a first time interval, sequentially emit radiation from the other radiation source at a second time interval longer than the first time interval, and detect the radiation at all times when the radiation is emitted from the two radiation sources. A radiation imaging apparatus comprising: an image acquisition unit that acquires a set of radiation images consisting of two radiation images including the target structure of the subject, generated by detecting two radiations emitted temporally adjacent from the two radiation sources using the detection unit; and a radiation imaging method in which the apparatus acquires a radiation image. The computer detects from each of the two radiographic images included in the set of radiographic images at least one common feature point, which is a point on a surgical instrument inserted into the subject, Using the positional relationship between the position of the at least one feature point detected from each of the two radiation images on the detection surface of the detection unit and the positions of the two radiation sources, three-dimensional positional information of the at least one feature point within the subject is derived. Using the radiographic image obtained by photographing the subject from the front and the radiographic image obtained by photographing from the side perpendicular to the front, three-dimensional information representing the three-dimensional position of at least one target point in the target structure within the subject is derived. A position information display screen that shows the positional relationship between the target point and the feature point on a common coordinate system between the target point and the feature point based on the position information and the three-dimensional information, the position information display screen including a radiation image display area and a position information display area is displayed on a display, The target structure is the lumbar vertebra of the subject, the target point is at least one of the insertion position and the destination position of the screw inserted into the lumbar vertebra, the surgical instrument is the screw, and the characteristic points are the tip and posterior end of the screw. A method for capturing radiographic images, comprising: displaying one of the two radiographic images included in the set of radiographic images in the radiographic image display area; and displaying a tomographic image of the target structure corresponding to photography from a direction different from the photography direction of the one radiographic image, a mark representing the target point, and a mark representing the feature point in the position information display area based on the positional relationship of the positional information and the three-dimensional information.

5. Two radiation sources arranged side by side at predetermined intervals, A detection unit is positioned opposite the two radiation sources and generates a radiation image of the subject by detecting radiation emitted from each of the two radiation sources and transmitted through the subject. A shooting control unit generates a radiation image of a subject by controlling the timing of radiation emission from each of the two radiation sources and the timing of detection of radiation that has passed through the subject by the detection unit, so as to sequentially emit radiation from one of the two radiation sources at a first time interval, sequentially emit radiation from the other radiation source at a second time interval longer than the first time interval, and detect the radiation at all times when the radiation is emitted from the two radiation sources. A radiation image acquisition program for causing a computer to execute a radiation image acquisition method in a radiation image acquisition apparatus comprising: an image acquisition unit that acquires a pair of radiation images consisting of two radiation images including the target structure of the subject, which are generated by detecting two radiations emitted temporally adjacent from the two radiation sources using the detection unit; A procedure for detecting at least one common feature point, which is a point on a surgical instrument inserted into the subject, from each of the two radiographic images included in the set of radiographic images, A procedure for deriving three-dimensional positional information of the at least one feature point within the subject by using the positional relationship between the position of the at least one feature point detected from each of the two radiation images on the detection surface of the detection unit and the positions of the two radiation sources, A procedure for deriving three-dimensional information representing the three-dimensional position of at least one target point in the target structure within the subject, using a radiographic image obtained by photographing the subject from the front and a radiographic image obtained by photographing it from the side perpendicular to the front. A position information display screen that shows the positional relationship between the target point and the feature point on a common coordinate system between the target point and the feature point based on the position information and the three-dimensional information, a procedure for displaying the position information display screen, which includes a radiation image display area and a position information display area, on a display; The computer is instructed to perform the following steps: display one of the two radiographic images included in the set of radiographic images in the radiographic image display area; display an image schematically representing the target structure corresponding to the image taken from the direction of the central axis of the target structure, which is the stent, and marks representing the feature points, in the position information display area based on the positional relationship of the positional information and the three-dimensional information; A radiographic imaging program in which the target structure is a stent inserted into the blood vessel of the subject, the target point is the central position of the end of the stent, the surgical instrument is a guide wire for expanding the stent, and the feature point is the tip of the guide wire.

6. Two radiation sources arranged side by side at predetermined intervals, A detection unit is positioned opposite the two radiation sources and generates a radiation image of the subject by detecting radiation emitted from each of the two radiation sources and transmitted through the subject. A shooting control unit generates a radiation image of a subject by controlling the timing of radiation emission from each of the two radiation sources and the timing of detection of radiation that has passed through the subject by the detection unit, so as to sequentially emit radiation from one of the two radiation sources at a first time interval, sequentially emit radiation from the other radiation source at a second time interval longer than the first time interval, and detect the radiation at all times when the radiation is emitted from the two radiation sources. A radiation image acquisition program for causing a computer to execute a radiation image acquisition method in a radiation image acquisition apparatus comprising: an image acquisition unit that acquires a pair of radiation images consisting of two radiation images including the target structure of the subject, which are generated by detecting two radiations emitted temporally adjacent from the two radiation sources using the detection unit; A procedure for detecting at least one common feature point, which is a point on a surgical instrument inserted into the subject, from each of the two radiographic images included in the set of radiographic images, A procedure for deriving three-dimensional positional information of the at least one feature point within the subject by using the positional relationship between the position of the at least one feature point detected from each of the two radiation images on the detection surface of the detection unit and the positions of the two radiation sources, A procedure for deriving three-dimensional information representing the three-dimensional position of at least one target point in the target structure within the subject, using a radiographic image obtained by photographing the subject from the front and a radiographic image obtained by photographing it from the side perpendicular to the front. A position information display screen that shows the positional relationship between the target point and the feature point on a common coordinate system between the target point and the feature point based on the position information and the three-dimensional information, a procedure for displaying the position information display screen, which includes a radiation image display area and a position information display area, on a display; The computer is instructed to perform the following steps: display one of the two radiation images included in the set of radiation images in the radiation image display area; and display the tomographic image of the target structure corresponding to an image taken from a direction different from the shooting direction of the one radiation image, a mark representing the target point, and a mark representing the feature point in the position information display area based on the positional relationship of the position information and the three-dimensional information. A radiographic imaging program wherein the target structure is the lumbar vertebra of the subject, the target point is at least one of the insertion position and the arrival position of a screw inserted into the lumbar vertebra, the surgical instrument is the screw, and the feature points are the tip and posterior end of the screw.

Images