X-ray diagnostic device and X-ray image acquisition method

Abstract

To improve operability on position adjustment in imaging.SOLUTION: An X-ray diagnostic device includes an X-ray tube, an X-ray detector, a designation part, and an image collection part. The X-ray tube irradiates a subject with an X-ray. The X-ray detector includes a first detector and a second detector whose visual field is smaller than that of the first detector, and outputs a detection signal on the basis of the X-ray passing through the subject and made incident. The designation part designates a plurality of positions in a first X-ray image generated on the basis of the detection signal of the first detector. The image collection part collects a plurality of second X-ray images by relatively moving at least one of the X-ray detector and a top plate on which the subject is placed with respect to the subject so that the plurality of positions are included in a third X-ray image composited from the plurality of second X-ray images generated based on the detection signals sequentially collected by the second detector.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The embodiments disclosed in this specification and drawings relate to an X-ray diagnostic apparatus and an X-ray image acquisition method. [Background technology]

[0002] Conventionally, there are X-ray diagnostic devices equipped with detectors that combine a large detector with normal resolution and a small detector with high-definition resolution. When imaging the lower extremities using such X-ray diagnostic devices, imaging such as stepping digital subtraction angiography (SDSA) is performed, in which the patient's lower extremities are imaged while the bed is moved in one direction.

[0003] In SDSA, for example, a procedure known as the rendezvous method involves moving a catheter from both the upstream and downstream sides of a blood vessel toward a stenotic site to guide a stent into the stenotic site. In this case, image display using a high-resolution detector is useful. However, because the field of view of a high-resolution detector is small, it can be difficult to adjust the position of the high-resolution detector's field of view to the site of interest when switching from the large field of view of a standard detector to the small field of view of a high-resolution detector. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-14922 Summary of the Invention [Problem to be solved by the invention]

[0005] One of the problems to be solved by the embodiments disclosed in this specification and the drawings is to improve operability regarding position adjustment during photography. However, the problems to be solved by the embodiments disclosed in this specification and the drawings are not limited to the above problem. Problems corresponding to the effects of each configuration shown in the embodiments described below can also be positioned as other problems. [Means for solving the problem]

[0006] The X-ray diagnostic apparatus according to this embodiment includes an X-ray tube, an X-ray detector, a designation unit, and an image acquisition unit. The X-ray tube irradiates an object with X-rays. The X-ray detector includes a first detector and a second detector having a smaller field of view than the first detector, and outputs a detection signal based on X-rays that have passed through and entered the object. The designation unit designates multiple positions in a first X-ray image generated based on the detection signal from the first detector. The image acquisition unit moves at least one of the X-ray detector and a tabletop on which the object is placed relative to the object so that the multiple positions are included in a third X-ray image synthesized from multiple second X-ray images generated based on detection signals sequentially acquired by the second detector, thereby acquiring the multiple second X-ray images. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of an X-ray diagnostic apparatus according to an embodiment. [Figure 2] FIG. 2 is a block diagram showing an example of the arrangement of an X-ray detector according to the embodiment. [Figure 3] FIG. 3 is a diagram showing an example of a floor-standing support device and a bed including a top board on which a subject is placed, according to the embodiment. [Figure 4] FIG. 4 is a diagram showing an example of a ceiling-suspended support device together with a bed according to the embodiment. [Figure 5] FIG. 5 is a diagram for explaining the acquisition processing operation of an X-ray image by the X-ray diagnostic apparatus according to the embodiment. [Figure 6] FIG. 6 is a flowchart showing an example of a procedure for high-definition photographing processing according to the embodiment. [Figure 7] FIG. 7 is a diagram showing an example of a first X-ray image, two designated positions, and three high-definition field-of-view sizes corresponding to three second imaging positions in the rendezvous method according to the embodiment. [Figure 8] FIG. 8 is a diagram showing an example of a third X-ray image according to the embodiment. [Figure 9] FIG. 9 is a diagram showing an outline of processing from imaging to display of a third X-ray image according to a third modified example of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of an X-ray diagnostic apparatus and an X-ray image acquisition method will be described in detail with reference to the drawings. In the following embodiments, parts with the same reference numerals perform similar operations, and redundant explanations will be omitted as appropriate.

[0009] (Embodiment) FIG. 1 is a diagram showing an example of the configuration of an X-ray diagnostic apparatus 1 according to this embodiment. In the following embodiment, an X-ray diagnostic apparatus for circulatory organs having a support arm in a holding device 19 will be described. The support arm supports an X-ray tube 13 and an X-ray detector 17. The X-ray detector 17 in the X-ray diagnostic apparatus 1 according to this embodiment includes, for example, a first detector and a second detector having a smaller field of view than the first detector. In other words, the field of view of the first detector is larger than the field of view of the second detector. Furthermore, the spatial resolution of the second detector is higher than the spatial resolution of the first detector. In other words, the second detector is a detector with higher resolution than the first detector.

[0010] The X-ray diagnostic apparatus 1 according to this embodiment may be realized by an X-ray diagnostic apparatus having a system (Micro Angiography Fluoroscope System: hereinafter referred to as MAF system) in which another detector (hereinafter referred to as detector B) can be arranged in front of a planar detector (hereinafter referred to as detector A) with a normal field of view. In this case, detector A in the MAF system corresponds to the first detector and has a larger detector element size and / or standard spatial resolution than detector B. In addition, detector B in the MAF system can be arranged in front of detector A. Detector B in the MAF system has a smaller detector element size and / or high spatial resolution than detector A. Detector B is attached to the C-arm by a holder mechanism. The holder mechanism supports detector B so that it can be freely moved between a park position and the X-ray irradiation range.

[0011] The X-ray diagnostic apparatus 1 includes an imaging unit 3, a bed 5, a drive unit 7, an operation unit 9, an X-ray high-voltage device 11, a processing circuit 21, a memory circuit 23, a display unit 25, and an input interface 27. The imaging unit 3 includes an X-ray tube 13 that irradiates X-rays onto the subject P and an X-ray detector 17 that detects the X-rays, and further includes an X-ray diaphragm 15 and a holding device 19. That is, the imaging unit 3 further includes a support arm. The bed 5 is provided with an operation unit 9 for operating the imaging unit 3 and the bed 5. The drive unit 7 that drives the imaging unit 3 and the bed 5 includes an imaging system movement drive unit 71 and a tabletop movement drive unit 73.

[0012] The X-ray high voltage device 11 includes electrical circuits such as a transformer and a rectifier, a high voltage generator, and an X-ray control device. The high voltage generator has the function of generating a high voltage to be applied to the X-ray tube 13 and a filament current to be supplied to the X-ray tube 13. The X-ray control device controls the output voltage according to the X-rays emitted by the X-ray tube 13. The high voltage generator may be of a transformer type or an inverter type. The X-ray high voltage device 11 may be provided in the holding device 19.

[0013] The X-ray tube 13 irradiates the subject P with X-rays. The X-ray tube 13 is a vacuum tube that generates X-rays by irradiating thermions from a cathode (filament) toward an anode (target) when a high voltage is applied from the X-ray high voltage device 11 and a filament current is supplied. X-rays are generated when thermions collide with the target. The X-ray tube 13 is, for example, a rotating anode type X-ray tube that generates X-rays by irradiating a rotating anode with thermions. Note that the type of the X-ray tube 13 is not limited to the rotating anode type, and any type of X-ray tube can be used.

[0014] The X-ray aperture 15 is provided in front of the X-ray radiation window in the X-ray tube 13. The X-ray aperture 15 has four aperture blades made of metal plates such as lead. The aperture blades are driven by a drive device (not shown) in accordance with the region of interest input by the operator via the operation unit 9 or the input interface 27. The X-ray aperture 15 adjusts the region where X-rays are blocked to any size by sliding the aperture blades with the drive device. With the adjusted aperture blades, the X-ray aperture 15 blocks X-rays outside the opening region. In this way, the X-ray aperture 15 narrows down the X-rays generated by the X-ray tube 13 so that they are irradiated onto the region of interest of the subject P.

[0015] The X-ray detector 17 outputs a detection signal based on the incident X-rays that are generated by the X-ray tube 13 and transmitted through the subject P. The X-ray detector 17 is realized by, for example, a flat panel detector (hereinafter referred to as FPD). The X-ray detector 17 has a first detector and a second detector having a smaller field of view than the first detector. The X-ray detector 17 according to this embodiment will be described below with reference to FIG. 2.

[0016] Fig. 2 is a block diagram showing an example of the configuration of the X-ray detector 17 according to this embodiment. As shown in Fig. 2, the X-ray detector 17 has a first photodetector 171, a second photodetector 173, and a scintillator 175. The first photodetector 171 and the second photodetector 173 detect light (scintillation light) generated in the scintillator 175 in response to incidence of X-rays. The first photodetector 171 and the scintillator 175 form a first detector 177 (also referred to as a first FPD). The second photodetector 173 and the scintillator 175 form a second detector 179 (also referred to as a second FPD).

[0017] The scintillator 175 converts X-rays emitted from the X-ray tube 13 into light. The first photodetector 171 includes, for example, a two-dimensional image sensor employing a TFT (Thin Film Transistor) array formed of amorphous silicon. The first photodetector 171 detects the light converted by the scintillator 175 and outputs an electrical signal. The second photodetector 173 includes, for example, a two-dimensional image sensor employing a CMOS (Complementary Metal Oxide Semiconductor) transistor. The second photodetector 173 detects the light converted by the scintillator 175 and outputs an electrical signal. The electrical signals output by the first photodetector 171 and the second photodetector 173 are also referred to as detection signals.

[0018] In this way, the scintillator 175 is shared by the first photodetector 171 and the second photodetector 173. In other words, the X-ray detector 17 includes the scintillator 175 that converts X-rays emitted from the X-ray tube 13 into light, and the first photodetector 171 and the second photodetector 173 that share the scintillator 175, detect the light converted by the scintillator 175, and output electrical signals. The first photodetector 171 and the second photodetector 173 simultaneously detect the light converted by the scintillator 175 and each output an electrical signal.

[0019] 2, the first photodetector 171 and the second photodetector 173 each have a plurality of element portions that are constituent units of pixels. Each of these element portions converts a fluorescent image obtained by incident X-rays into an electrical signal and accumulates the signal in a photodiode (PD). In the example of FIG. 2, the first photodetector 171 has eight element portions, and the second photodetector 173 has eight element portions.

[0020] Here, the pixel pitch of each element unit of the second photodetector 173 is finer than the pixel pitch of each element unit of the first photodetector 171. In the example shown in FIG. 2, the pixel pitch of each element unit of the first photodetector 171 corresponds to the pixel pitch of two element units of the second photodetector 173. That is, the second photodetector 173 has a higher resolution than the first photodetector 171. Also, as shown in FIG. 2, the field of view size of the first photodetector 171 is wider than the field of view size of the second photodetector 173. In other words, the field of view size of the second photodetector 173 is narrower than the field of view size of the first photodetector 171.

[0021] The following describes the configuration of the floor-standing support device 19 and the bed 5, and the movement or rotation of each unit constituting the support device 19 and the bed 5. Fig. 3 is a diagram showing an example of the floor-standing support device 19 and the bed 5 including a top board 51 on which the subject P is placed. The support device 19 has a C-arm 191 corresponding to a support arm, an arm holder 193, a stand 195, and a floor-mounted rotating arm 197. The bed 5 has the top board 51 and a base 53. In Fig. 3, to facilitate the following description, the longitudinal direction of the bed 5 is defined as the y-axis, the vertical direction is defined as the z-axis, and the direction perpendicular to the y-axis and z-axis is defined as the x-axis.

[0022] The configuration of the support device 19 and the bed 5 shown in Fig. 3 is an example and is not limited to this. The support arm is not limited to the floor-mounted C-arm 191 as shown in Fig. 3, but may be, for example, an Ω-arm suspended from the ceiling. Furthermore, an X-ray diagnostic apparatus for cardiovascular use may have a C-arm 191 and an Ω-arm.

[0023] The drive unit 7 includes an imaging system movement drive unit 71 and a tabletop movement drive unit 73. The imaging system movement drive unit 71 drives the imaging unit 3 to move the imaging system, such as the X-ray tube 13 and the X-ray detector 17, in a desired direction under the control of the control function 211 in the processing circuit 21. The imaging system movement drive unit 71 is provided on the support device 19, for example, for each of a plurality of support members (C-arm 191, arm holder 193, stand 195, and floor rotating arm 197) that support a plurality of components to be moved. The tabletop movement drive unit 73 drives the bed 5 to move the tabletop 51 in a desired direction under the control of the control function 211. The tabletop movement drive unit 73 is provided on the bed 5, for example. The imaging system movement drive unit 71 and the tabletop movement drive unit 73 are realized by motors, actuators, or the like.

[0024] The C-arm 191 supports the X-ray tube 13, the X-ray diaphragm 15, and the X-ray detector 17 at both ends. In other words, the X-ray tube 13 and the X-ray detector 17 are attached to the ends of the C-arm 191 facing each other. The C-arm 191 supports the X-ray diaphragm 15 and the X-ray detector 17 so that they can rotate freely around the rotation axis z1, which is a line connecting the focal point where X-rays are generated in the X-ray tube 13 and the center of the X-ray detector 17. The C-arm 191 rotates the X-ray diaphragm 15 and the X-ray detector 17 around the rotation axis z1 as shown by arrow a by the operation of the imaging system movement drive unit 71 (hereinafter referred to as detector rotation).

[0025] The C-arm 191 supports the X-ray detector 17 so as to change the source image distance (hereinafter referred to as SID), which corresponds to the distance between the X-ray tube 13 and the X-ray detector 17. That is, the C-arm 191 supports the X-ray detector 17 so as to be slidable along the arrow b. The C-arm 191 slides the X-ray detector 17 along the arrow b by the operation of the imaging system movement driver 71 (hereinafter referred to as SID change).

[0026] Arm holder 193 supports C-arm 191 so that it can slide freely around rotation axis z2, which is a direction perpendicular to a plane that passes through isocenter ISC and includes C-arm 191. Arm holder 193 slides C-arm 191 around rotation axis z2 as shown by arrow c by operation of imaging system movement drive unit 71 (hereinafter referred to as C-arm slide). Arm holder 193 is supported by stand 195.

[0027] The stand 195 rotatably supports the arm holder 193 around a rotation axis z3 that passes through the isocenter ISC and is perpendicular to the rotation axes z1 and z2. The stand 195 rotates the arm holder 193 around the rotation axis z3 as shown by the arrow d by the operation of the imaging system movement drive unit 71 (hereinafter referred to as the main rotation). The stand 195 is supported by a floor-mounted rotating arm 197.

[0028] The floor rotating arm 197 rotatably supports the stand 195 with a rotation axis z4 that is a vertical direction passing through the connection part between the stand 195 and the floor rotating arm 197. The floor rotating arm 197 rotates the stand 195 around the rotation axis z4 as shown by the arrow e by operation of the imaging system movement drive unit 71 (hereinafter referred to as support rotation). The floor rotating arm 197 is installed on the floor surface 199 so as to be rotatable with a rotation axis z5 that is a vertical direction passing through the connection part between the floor rotating arm 197 and the floor surface 199. The floor rotating arm 197 rotates around the rotation axis z5 as shown by the arrow f by operation of the imaging system movement drive unit 71 (hereinafter referred to as floor rotation).

[0029] In addition, differences from FIG. 3 in the case where the support device 19 is configured as a ceiling-suspended type will be briefly described using FIG. 4. FIG. 4 is a diagram showing an example of a ceiling-suspended support device 19 together with a bed 5. Note that in FIG. 4, the display 251 and the like are omitted as appropriate. As shown in FIG. 4, the floor rotating arm 197 shown in FIG. 3 is supported as a ceiling rotating arm 201 on a base 203 so as to be rotatable about a rotation axis z5. The ceiling rotating arm 201 rotates about the rotation axis z5 by the operation of the imaging system movement drive unit 71 (hereinafter referred to as ceiling rotation). The base 203 is supported on a rail (hereinafter referred to as a ceiling rail) 205 installed on the ceiling of the examination room so as to be slidable along a direction parallel to the rail (hereinafter referred to as the rail direction (x direction in FIG. 4)) and a direction perpendicular to the rail direction (hereinafter referred to as the rail perpendicular direction (y direction in FIG. 4)). The base 203 moves in parallel along the rail direction or a direction perpendicular to the rail by the operation of the imaging system movement drive unit 71 (hereinafter referred to as a ceiling slide).

[0030] With the above-described configuration, the holding device 19 can move the X-ray tube 13 and the X-ray detector 17 to any position desired by the operator relative to the subject P. Note that the holding device 19 is not limited to having the rotation axes z1 to z5 shown in FIG. 3 and can be configured in any way. The holding device 19 moves the X-ray tube 13 and the X-ray detector 17 by the operation of the imaging system movement driver 71 based on instructions from the operator via the operation unit 9.

[0031] The base 53 supports the tabletop 51 so that it can move in parallel along the z-axis. The tabletop movement drive unit 73 operates to move the tabletop 51 in parallel along the z-axis as shown by arrow g (hereinafter referred to as tabletop up-and-down movement). The base 53 supports the tabletop 51 so that it can move in parallel along the long axis direction of the tabletop 51. The base 53 operates to move the tabletop 51 in parallel along the long axis direction of the tabletop 51 as shown by arrow h (hereinafter referred to as tabletop sliding).

[0032] The base 53 supports the top 51 so that it can tilt, with the long axis direction of the top 51 serving as a rotation axis z6. The base 53 tilts the top 51 around the rotation axis z6 as shown by arrow j by the operation of the top movement drive unit 73. The base 53 supports the top 51 so that it can tilt, with the short axis direction of the top 51 serving as a rotation axis z7. The base 53 tilts the top 51 around the rotation axis z7 as shown by arrow k by the operation of the top movement drive unit 73. Hereinafter, the operation related to the tilt of the top 51 will be referred to as top tilt.

[0033] The operation unit 9 corresponds to a console used to operate the X-ray diagnostic apparatus 1. The operation unit 9 has a handle that is held by the operator and various switches. The handle is held, for example, by the operator's thumb, index finger, and middle finger. The handle may be held by the operator's other fingers or may be gripped by the fingers of the operator's hand. The handle may also be held by the operator's hand. The handle is, for example, a joystick. The operation unit 9 accepts operations for operating at least one of the imaging unit 3 and the bed 5 by operating the handle. In other words, the operation unit 9 corresponds to a console that accepts operations for operating at least one of the imaging unit 3 and the bed 5. The operation unit 9 outputs an operation signal related to the operation of the handle to the processing circuitry 21.

[0034] The processing circuitry 21 controls the overall operation of the X-ray diagnostic apparatus 1 based on electrical signals of input operations output from the operation unit 9 or the input interface 27. For example, the processing circuitry 21 has, as hardware resources, processors such as a CPU (Central Processing Unit), an MPU (Micro Processing Unit), and a GPU (Graphics Processing Unit), and memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory).

[0035] Various processing functions executed by the processing circuitry 21 are stored in the form of computer-executable programs in the storage circuitry 23. The processing circuitry 21 is a processor that realizes the functions corresponding to each program by reading and executing the programs from the storage circuitry 23. In other words, each circuit that has read each program has the function corresponding to the read program.

[0036] The processing circuitry 21 executes the image acquisition function 210 using a processor that executes a program loaded in memory. The processing circuitry 21 that executes the image acquisition function 210 corresponds to an image acquisition unit. The image acquisition function 210 acquires a plurality of second X-ray images by moving at least one of the X-ray detector 17 and the tabletop 51 on which the subject P is placed relative to the subject P so that a third X-ray image composed of a plurality of second X-ray images generated based on detection signals sequentially acquired by the second detector 179 includes a plurality of positions described below. For example, the image acquisition function 210 acquires a plurality of second X-ray images by moving at least one of the X-ray detector 17 and the tabletop 51 relative to the subject P along at least one straight line passing through the plurality of positions from one end point to the other end point of the plurality of positions. The plurality of positions are designated by the operator in the first X-ray image generated based on the detection signal of the first detector 177. Specifically, the image collection function 210 sequentially moves at least one of the X-ray detector 17 and the tabletop 51 relative to one another to a plurality of shooting positions determined by the determination function 215, and collects a plurality of second X-ray images.

[0037] More specifically, the image collection function 210 includes, for example, a control function 211, an image generation function 213, and a decision function 215. In this case, the processing circuitry 21 executes the control function 211, the image generation function 213, and the decision function 215 using a processor that executes a program loaded in memory. The processing circuitry 21 that executes the control function 211, the image generation function 213, and the decision function 215, respectively, corresponds to a control unit, an image generation unit, and a decision unit. Note that the control function 211, the image generation function 213, and the decision function 215 are not limited to being realized by a single processing circuit. A processing circuit may be configured by combining multiple independent processors, and the control function 211, the image generation function 213, and the decision function 215 may be realized by each processor executing a program.

[0038] In addition, the processing circuit 21 may be realized by a processor such as an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), other Complex Programmable Logic Devices (CPLDs), or Simple Programmable Logic Devices (SPLDs).

[0039] The processing circuitry 21 controls the drive unit 7, the X-ray high voltage generator 11, the X-ray aperture 15, the memory circuitry 23, the display unit 25, the image generation function 213, the decision function 215, etc., based on an input operation received from an operator via the operation unit 9 or the input interface 27, using the control function 211. Specifically, the control function 211 reads out a control program stored in the memory circuitry 23, loads it on the memory in the processing circuitry 21, and controls each part of the X-ray diagnostic apparatus 1 according to the loaded control program. The control function 211 also controls the timing of readout of electrical signals by the X-ray detector 17. In this way, the control function 211 collects electrical signals from the X-ray detector 17. For example, the control function 211 collects electrical signals from the first detector 177. The control function 211 also collects electrical signals from the second detector 179.

[0040] The processing circuitry 21 generates image data based on the output from the X-ray detector 17 using the image generation function 213. Specifically, the processing circuitry 21 generates projection data based on the output from the X-ray detector 17. Next, the processing circuitry 21 receives an input signal from the operation unit 9 or the input interface 27 and performs image processing such as filtering on the projection data to generate image data. The image data corresponds to medical image data including fluoroscopic images and radiographic images of the subject P. The processing circuitry 21 performs synthesis processing, subtraction processing, and the like using the image data. The processing circuitry 21 outputs the generated image data to the memory circuitry 23 or the display unit 25. For example, the image generation function 213 generates a first X-ray image based on a detection signal from the first detector 177. The image generation function 213 also generates multiple second X-ray images based on detection signals sequentially collected by the second detector 179. The image generation function 213 then generates a third X-ray image by synthesizing the multiple second X-ray images. For example, the image generating function 213 generates a third X-ray image as a long image by joining together the same positions in a plurality of second X-ray images.

[0041] The processing circuitry 21 determines, through the determination function 215, multiple imaging positions (hereinafter referred to as second imaging positions) for generating multiple second X-ray images based on the position of the X-ray detector 17 in generating the first X-ray image (hereinafter referred to as first imaging position), the size of the small field of view in the second detector 179 (hereinafter referred to as high-resolution field of view size), and multiple positions (hereinafter referred to as designated positions) designated in the first X-ray image. For example, the determination function 215 determines a straight line connecting the designated positions in the first X-ray image. Next, the determination function 215 determines the center position of the multiple high-resolution field of view sizes (hereinafter referred to as high-resolution center position) in the first X-ray image so that the high-resolution field of view sizes are adjacent or a predetermined area overlaps in continuously moved high-resolution field of view sizes from the start point to the end point of the determined straight line.

[0042] Next, the determination function 215 determines the amount of movement and the direction of movement for at least one of the X-ray detector 17 and the tabletop 51 based on the relative positional relationship between the specified position and the center position of the first X-ray image and the multiple high-resolution center positions. The determination function 215 determines multiple second imaging positions corresponding to the multiple high-resolution center positions using the determined amount of movement and direction of movement based on the first imaging position.

[0043] The memory circuitry (memory) 23 is a storage device such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or an integrated circuit storage device that stores various information. The memory circuitry 23 stores, for example, projection data, image data, a first imaging position, a second imaging position, and programs corresponding to various functions read and executed by the processing circuitry 21. In addition to an HDD or an SSD, the memory circuitry 23 may be a drive device that reads and writes various information from / to a portable storage medium such as a CD (Compact Disc), a DVD (Digital Versatile Disc), or a flash memory, or a semiconductor memory element such as a RAM (Random Access Memory). The storage area of ​​the memory circuitry 23 may be in an external storage device connected via a network.

[0044] The display unit 25 is composed of a display 251 that displays medical images g1 including the first X-ray image and the third X-ray image, an internal circuit that supplies display signals to the display 251, and peripheral circuits such as connectors and cables that connect the display 251 to the internal circuit. The internal circuit generates display data by superimposing additional information such as subject information and projection data generation conditions on the image data. Next, the internal circuit performs D / A conversion and TV format conversion on the obtained display data. The internal circuit displays the display data after these conversions on the display 251 as a medical image g1. For example, the display unit 25 displays a specified position superimposed on the displayed first X-ray image. In addition, the display unit 25 displays a GUI (Graphical User Interface) and the like in the display area g2 for receiving various operations from the operator.

[0045] For example, a liquid crystal display (LCD), a cathode ray tube (CRT) display, an organic electroluminescence display (OLED), a plasma display, or any other display can be appropriately used as the display 251. The display 251 may be a desktop type, or may be configured as a tablet terminal or the like capable of wireless communication with the processing circuit 21.

[0046] The input interface 27 accepts various input operations from the operator, converts the accepted input operations into electrical signals, and outputs the electrical signals to the processing circuitry 21. For example, the input interface 27 designates multiple positions in the first X-ray image generated and displayed based on the detection signal of the first detector 177, in response to instructions from the operator. At this time, the input interface 27 functions as a designation unit. Note that the designation unit that designates multiple positions in the first X-ray image may be realized by the operation unit 9. The first X-ray image that is the input target for the designated positions is, for example, an LIH (Last Image Hold) image, the most contrast-enhanced image of a series of fluoroscopic images of the subject, an image selected by the operator from the series of fluoroscopic images, a bottom trace image generated by bottom trace processing on the series of fluoroscopic images, etc.

[0047] Here, the LIH image refers to the last image collected in a series of fluoroscopic images collected by X-ray fluoroscopy. The LIH image is usually continuously displayed on the display 251 after the X-ray fluoroscopy. X-ray fluoroscopy is frequently performed during a procedure, and by using the LIH image to input a specified position, a third X-ray image can be generated and displayed at the appropriate time during the procedure.

[0048] Bottom trace processing is a process for creating an image in which the value of each pixel is the minimum value that the pixel takes in a series of fluoroscopic images. A bottom trace image is equivalent to a composite of images of the moment when the contrast agent is most concentrated in each pixel. Therefore, by using such a bottom trace image to input the specified position, it is possible to reduce the amount of contrast agent used in the acquisition stage of the first X-ray image, which is a preparatory stage for acquiring the third X-ray image.

[0049] The input interface 27 also receives from the operator operations for operating at least one of the imaging unit 3 and the bed 5, X-ray conditions related to the generation of X-rays, conditions related to image processing executed by the image generation function 213, etc. As the input interface 27, for example, a mouse, keyboard, trackball, switch, button, joystick, foot switch, touchpad, touch panel display, etc. can be used as appropriate. The input interface 27 is mounted on, for example, a console device and the bed 5 installed in an operation room different from the examination room. The input interface 27 may also be provided in the support device 19.

[0050] In this embodiment, the input interface 27 is not limited to one having physical operation parts such as a mouse, keyboard, trackball, switch, button, joystick, touchpad, and touch panel display. For example, an example of the input interface 27 is an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the device and outputs the electrical signal to the processing circuit 21. The input interface 27 may be configured as a tablet terminal or the like that can wirelessly communicate with the processing circuit 21.

[0051] The overall configuration of the X-ray diagnostic apparatus 1 according to the embodiment has been described above. In this configuration, the X-ray diagnostic apparatus 1 according to the embodiment collects detection signals output by the X-ray detector 17. Then, the X-ray diagnostic apparatus 1 displays an X-ray image generated from the collected detection signals on the display 251. For example, the X-ray diagnostic apparatus 1 displays an X-ray image set by the operator according to the clinical site on the display 251. Furthermore, the X-ray diagnostic apparatus 1 switches between a first X-ray image and a second X-ray image according to an instruction from the operator and displays them on the display 251.

[0052] In such an X-ray diagnostic apparatus 1, there are cases where the second detector 179 on the side of the second photodetector 173, which has high resolution but a narrow field of view, is used for a relatively long time in a medical procedure, etc. Fig. 5 is a diagram for explaining the collection processing operation of an X-ray image by the X-ray diagnostic apparatus 1.

[0053] The left diagram in Fig. 5 shows a case where the region to be irradiated with X-rays is set to the field of view size of the second detector 179. In this case, the X-ray diagnostic apparatus 1 collects the detection signals output by the second detector 179 and displays a second X-ray image on the display 251. Note that in this case as well, the X-ray diagnostic apparatus 1 collects the detection signals output by the first detector 177 and generates a first X-ray image. In the first X-ray image, a field of view that matches the field of view size of the second detector 179 and X-ray collimator blades are depicted around this field of view.

[0054] Next, the image displayed on the display 251 is changed from the second X-ray image to the first X-ray image. The right diagram in FIG. 5 shows a case where the area to be irradiated with X-rays is changed to the field of view size of the first detector 177. In this case, the X-ray diagnostic apparatus 1 collects the detection signals output by the first detector 177 and displays the first X-ray image on the display 251. Note that in this case as well, the X-ray diagnostic apparatus collects the detection signals output by the second detector 179 and generates a second X-ray image. In the second X-ray image, a field of view that matches the field of view size of the second detector 179 is depicted.

[0055] 5, the imaging centers of the first detector 177 and the second detector 179 are aligned. Therefore, when switching from the first X-ray image to the second X-ray image, the second X-ray image is an image in which the central portion of the first X-ray image is enlarged in accordance with the high-definition field of view size. Therefore, when generating the second X-ray image at a position different from the center of the first X-ray image, the X-ray diagnostic apparatus 1 needs to perform position adjustment to move the field of view of the second detector 179 to the region of interest.

[0056] Therefore, the X-ray diagnostic apparatus 1 controls the drive unit 7 and the X-ray detector 17 according to the plurality of second imaging positions, and executes a process (hereinafter referred to as high-definition imaging process) of imaging the subject P using the second detector 179. Specifically, the high-definition imaging process is a process in which, after the control function 211 inputs a plurality of designated positions for the first X-ray image, at least one of the X-ray detector 17 and the tabletop 51 is moved to a plurality of second imaging positions, and the subject P is imaged using the second detector 179.

[0057] The procedure for the high-definition photography processing will be described below with reference to Fig. 6. Fig. 6 is a flowchart showing an example of the procedure for the high-definition photography processing. The high-definition photography processing is executed by the image collection function 210. The processing contents of the high-definition photography processing will be described below with respect to the control function 211, image generation function 213, and decision function 215 in the image collection function 210.

[0058] (High-definition photography processing) (Step S601) The control function 211 adjusts the area to be irradiated with X-rays (hereinafter referred to as the irradiation area) to the field of view size of the first detector 177, and controls the irradiation of X-rays to the subject P. The image generation function 213 generates a first X-ray image based on the detection signal from the first detector 177. The display 251 displays the generated first X-ray image (for example, an LIH image or a bottom trace image).

[0059] (Step S602) The input interface 27, which functions as a designation unit, designates (inputs) a plurality of positions in the first X-ray image displayed on the display 251 in accordance with instructions from the operator. The input interface 27 may input straight lines, curves, etc. as the plurality of positions (designated positions). The input interface 27 may also input a predetermined area by enclosing it as the plurality of positions (designated positions).

[0060] (Step S603) The determination function 215 reads out the first imaging position associated with the first X-ray image from the storage circuitry 23. The determination function 215 determines a plurality of second imaging positions based on the first imaging position, the high-definition field of view size, and the designated position. At this time, the determination function 215 may superimpose the designated position and the high-definition field of view size corresponding to the second imaging position on the first X-ray image and display it on the display 251.

[0061] FIG. 7 is a diagram showing an example of a first X-ray image, two designated positions, and three high-resolution field-of-view sizes corresponding to three second imaging positions in the rendezvous method. The dotted-line frames in FIG. 7 indicate the three high-resolution field-of-view sizes. Also, in FIG. 7, the blood vessel between the two designated positions indicates a stenosis site. That is, the two designated positions are designated by the operator via the designation unit so as to indicate the approximate start and end points of the stenosis site. As shown in FIG. 7, the determination function 215 displays on the display 251 two high-resolution field-of-view sizes corresponding to the two designated positions, respectively, and the middle high-resolution field-of-view size that overlaps between these two high-resolution field-of-view sizes. At this time, the display 251 may display a straight line connecting the two designated positions.

[0062] (Step S604) The control function 211 controls the drive unit 7, the X-ray high voltage device 11, the X-ray detector 17, etc. to perform X-ray imaging using the second detector 179 at multiple second imaging positions. For example, the control function 211 controls the drive unit 7 to sequentially move at least one of the X-ray detector 17 and the tabletop 51 to multiple second imaging positions. The control function 211 performs X-ray imaging at each of the multiple second imaging positions and collects detection signals from the second detector 179. The image generation function 213 generates multiple second X-ray images corresponding to the multiple second imaging positions using the multiple detection signals corresponding to the multiple second imaging positions. Note that the control function 211 may also control the drive unit 7 to sequentially move at least one of the X-ray detector 17 and the tabletop 51 to multiple second imaging positions.

[0063] (Step S605) The image generation function 213 generates a third X-ray image by aligning and combining multiple second X-ray images. The third X-ray image corresponds to a long image with the head direction of the subject P as the long axis. FIG. 8 is a diagram showing an example of the third X-ray image. As shown in FIG. 8, the upper side of the third X-ray image indicates the head direction of the subject P. If multiple specified positions are not on a straight line in the craniocaudal direction (for example, if the stenosis site is in the left-right direction), the long image will be a stepped image in the craniocaudal direction.

[0064] (Step S606) The display unit displays the third X-ray image on the display 251. At this time, the upper end side of the image display area on the display 251 corresponds to the upper end of the third X-ray image.

[0065] According to the X-ray diagnostic apparatus 1 of the embodiment described above, a first X-ray image is generated based on a detection signal from the first detector 177 of the X-ray detector 17, which has the first detector 177 and a second detector 179 having a smaller field of view than the first detector 177. A plurality of positions are specified in the first X-ray image. A third X-ray image is generated from a plurality of second X-ray images generated based on detection signals sequentially collected by the second detector 179. At least one of the X-ray detector 17 and the tabletop 51 on which the subject P is placed is moved relative to the subject P so that the plurality of positions (specified positions) are included in the third X-ray image. For example, according to the present X-ray diagnostic apparatus 1, a plurality of second X-ray images are collected by moving at least one of the X-ray detector 17 and the tabletop 51 from one end point to the other end point of the plurality of positions along at least one straight line passing through the plurality of positions.

[0066] Specifically, according to the X-ray diagnostic apparatus 1 of the embodiment, multiple shooting positions (second shooting positions) for generating multiple second X-ray images are determined based on the position (first shooting position) of the X-ray detector 17 in generating the first X-ray image, the size of the small field of view (high-resolution field of view size), and multiple positions (designated positions), and at least one of the X-ray detector 17 and the tabletop 51 is moved sequentially to the multiple determined shooting positions (second shooting positions) to collect multiple second X-ray images.

[0067] As a result, with the present X-ray diagnostic apparatus 1, even if the center position of the first X-ray image and the high-resolution center position desired by the operator as the region of interest of the imaging subject are separated, imaging related to the generation of multiple second X-ray images can be easily performed by inputting multiple specified positions in the first X-ray image without manually adjusting the positions of the X-ray detector 17, the tabletop 51, etc. Therefore, with the present X-ray diagnostic apparatus 1, it is possible to easily set the imaging range of the high-resolution detector for the region of interest, thereby shortening the procedure for the subject P. As described above, with the present X-ray diagnostic apparatus 1, it is possible to generate and display a third X-ray image by inputting specified positions in the first X-ray image, thereby improving the operability of generating the third X-ray image and the throughput of the procedure and examination for the subject P, and improving the workflow for generating high-resolution long images. Furthermore, for example, when an LIH image is used as the first X-ray image, the present X-ray diagnostic apparatus 1 makes it possible to generate and display the third X-ray image as needed during the procedure. Furthermore, for example, when a bottom trace image is used as the first X-ray image, the X-ray diagnostic apparatus 1 can reduce the amount of contrast agent used in the acquisition stage of the first X-ray image, which is a preparatory stage for acquiring the third X-ray image. This can improve the throughput of the examination and reduce the burden of administering a contrast agent to the subject P.

[0068] (First Modification) In this modification, a blood vessel angiogram and a device are automatically recognized in the first X-ray image, and a continuous imaging range is set so that the blood vessel and the device can be imaged. The processing content of step S603 in the high-definition imaging process of this modification is as follows.

[0069] The determination function 215 determines at least one of the position of the stenosis portion of the blood vessel in the first X-ray image and the position of the device located in the blood vessel based on the first X-ray image. For example, the determination function 215 determines the position of the stenosis portion and the position of the device in the first X-ray image by performing image recognition processing on the first X-ray image. The image recognition processing is realized by various image processing methods, such as various segmentation processes or trained models trained to realize image recognition processing (e.g., trained neural networks that realize semantic segmentation). The determination function 215 determines multiple second imaging positions based on at least one of the position of the stenosis portion and the position of the device, the first imaging position, the high-resolution field of view size, and the specified position. As a result, the image collection function 210 sequentially moves at least one of the X-ray detector 17 and the tabletop 51 to the multiple second imaging positions to collect multiple second X-ray images.

[0070] According to the X-ray diagnostic apparatus 1 of the first modification of the embodiment described above, at least one of the position of the stenosis in the blood vessel and the position of the device located in the blood vessel is determined based on the first X-ray image, and multiple imaging positions for generating multiple second X-ray images are determined based on at least one of the determined position of the stenosis and the position of the device, the position of the X-ray detector in generating the first X-ray image, the size of the small field of view, and multiple positions, and at least one of the X-ray detector 17 and the tabletop 51 is moved sequentially to the multiple imaging positions to collect multiple second X-ray images. The effects of the first modification are similar to those of the embodiment, so description will be omitted.

[0071] (Second Modification) In this modified example, when a plurality of positions (designated positions) are included within the width of a small field of view (high-definition field of view size) along a direction perpendicular to the body axis direction of the subject P in the first X-ray image, at least one of the X-ray detector 17 and the tabletop 51 is moved along the body axis direction relative to the subject P to collect a plurality of second X-ray images. That is, when the width along the x direction (hereinafter referred to as the field of view width) of the second detector 179 includes all of the designated positions with different coordinates in the y direction, the image collection function 210 translates at least one of the X-ray detector 17 and the tabletop 51 along the y direction to collect a plurality of second X-ray images.

[0072] Specifically, the determination function 215 determines whether all designated positions with different y-coordinates are included in the field of view width. If all designated positions with different y-coordinates are included in the field of view width, the determination function 215 calculates the average value of the x-coordinates at the designated positions. Next, the determination function 215 determines multiple high-resolution center positions based on the y-coordinates of the start and end points at the designated positions, the average value, and the length of the second detector 179 along the y-direction so that the high-resolution field of view sizes are adjacent or so that a predetermined area overlaps in continuously moved high-resolution field of view sizes. The determination function 215 determines the amount of movement for at least one of the X-ray detector 17 and the tabletop 51 based on the relative positional relationship between the multiple high-resolution center positions and the center position of the first X-ray image. The determination function 215 determines multiple second imaging positions corresponding to the multiple high-resolution center positions using the determined amount of movement, based on the first imaging position.

[0073] In this modification, the second imaging positions are on parallel straight lines in the y direction, and therefore the third X-ray image generated in this modification is a long image as shown in FIG.

[0074] According to the X-ray diagnostic apparatus 1 of the first modified example of the embodiment described above, when a plurality of positions (specified positions) are included within the width of the small field of view along the direction (x direction) perpendicular to the body axis direction (y direction) of the subject P in the first X-ray image, at least one of the X-ray detector 17 and the table top 51 is moved along the body axis direction to collect a plurality of second X-ray images. The effects of this modified example are similar to those of the embodiment, so a description thereof will be omitted.

[0075] (Third Modification) In this modification, when multiple positions (specified positions) are included within the width of a small field of view (high-resolution field of view size) in a direction perpendicular to the body axis direction of the subject P in the first X-ray image, the X-ray detector 17 is rotated according to the angle between a regression line for the multiple positions and the body axis direction, and the X-ray detector 17 is translated in a direction along the regression line to collect multiple second X-ray images. That is, when all specified positions with different coordinates in the x and y directions are included within the field of view width, the image collection function 210 rotates the X-ray detector 17 according to the angle between the regression line for the multiple positions and the body axis direction, and translates the rotated X-ray detector 17 in a direction along the regression line to collect multiple second X-ray images. In implementing this modification, the X-ray detector 17 needs to be rotatable around the line (SID) connecting the X-ray tube 13 and the X-ray detector 17 as the rotation axis.

[0076] In addition, in this modification, the third X-ray image is rotated according to the angle, so that the up-down direction of the image display area coincides with the body axis direction in the third X-ray image, and the third X-ray image is displayed. That is, the display unit 25 displays the third X-ray image on the display 251 so that the up-down direction of the image display area coincides with the body axis direction in the third X-ray image.

[0077] The determination function 215 determines whether all designated positions with different x- and y-coordinates are included in the field of view width. If all designated positions with different x- and y-coordinates are included in the field of view width, the determination function 215 calculates a regression line for the multiple positions (designated positions). The determination function 215 calculates the angle between the regression line and the body axis direction, i.e., the angle between the regression line and the y-axis. The determination function 215 determines multiple high-resolution center positions based on the start and end points of the regression line so that the high-resolution field of view sizes are adjacent or so that a predetermined area overlaps in continuously shifted high-resolution field of view sizes. The determination function 215 determines the movement amount of the X-ray detector 17 based on the relative positional relationship between the multiple high-resolution center positions and the center position of the first X-ray image. The determination function 215 uses the determined movement amount to determine multiple second imaging positions along the regression line that correspond to the multiple high-resolution center positions, based on the first imaging position.

[0078] The control function 211 rotates the X-ray detector 17 around the rotation axis z1 according to the calculated angle. Next, the control function 211 controls the drive unit 7 to maintain the rotated state of the X-ray detector 17 and translate the X-ray detector 17 to each of the multiple second imaging positions in a direction along the regression line. At this time, the control function 211 images the subject P at each of the multiple second imaging positions. Therefore, the multiple second imaging positions in this modified example are on a line parallel to the regression line. As a result, the third X-ray image generated in this modified example is an elongated image whose major axis is in the direction along the regression line. The generated third X-ray image is stored in the memory circuitry 23 with the major axis in the direction along the regression line.

[0079] The display unit 25 reads out the stored third X-ray image. Then, the display unit 25 rotates the third X-ray image according to the angle. The display unit 25 displays the third X-ray image on the display 251 in a state where the up-down direction of the image display area coincides with the body axis direction in the third X-ray image.

[0080] FIG. 9 is a diagram showing an overview of the process from imaging to display of a third X-ray image in this modified example. In the imaging shown in FIG. 9, four high-definition field-of-view sizes HD corresponding to four second imaging positions are shown. As shown in FIG. 9, the image acquisition function 210 rotates the X-ray detector 17 by an angle θ between the regression line RL and the y-axis, and then moves the X-ray detector 17 along the regression line RL to perform high-definition imaging processing. The third X-ray image generated by the image generation function 213 is stored in the memory circuitry 23 with the longitudinal direction of the third X-ray image (the direction of the regression line RL) as the vertical axis, as shown in FIG. 9, for example. When the third X-ray image is displayed in the image display area of ​​the display 251, the display unit 25 displays the third X-ray image rotated by the angle θ on the display 251, as shown in FIG. 9. As shown in FIG. 9, the third X-ray image displayed in the image display area is displayed with the up-down direction of the image display area and the body axis direction (y direction) of the third X-ray image aligned.

[0081] When the technical idea of ​​this embodiment is realized in an X-ray image acquisition method, the X-ray image acquisition method specifies multiple positions in a first X-ray image generated based on a detection signal from an X-ray detector 17 having a first detector 177 and a second detector 179 with a smaller field of view than the first detector 177, and moves at least one of the X-ray detector 17 and the tabletop 51 on which the subject P is placed relative to the subject P so that the multiple positions (specified positions) are included in a third X-ray image generated based on detection signals sequentially acquired by the second detector 179, thereby acquiring multiple second X-ray images. The processing procedure of the X-ray image acquisition method conforms to high-definition imaging processing. Furthermore, the effects of the X-ray image acquisition method are similar to those of the embodiment. For these reasons, a description of the processing procedure and effects of the X-ray image acquisition method will be omitted.

[0082] According to at least the embodiment and modified examples described above, it is possible to improve the operability regarding position adjustment during imaging.

[0083] Although several embodiments have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations of embodiments can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0084] 1 X-ray diagnostic equipment 3. Imaging unit 5 berths 7 Drive unit 9 Control section 11. X-ray high voltage device 13 X-ray tube 15 X-ray aperture 17 X-ray detector 19 Holding device 21 Processing circuit 23 Memory circuit (memory) 25 Display section 27 Input Interface 51 Top plate 53 Foundation 71 Imaging system movement drive unit 73 Top plate movement drive unit 171 First Photodetector 173 Second Photodetector 175 Scintillator 177 First Detector 179 Second Detector 191 Support arm (C-arm) 193 Arm Holder 195 Stand 197 Floor Swivel Arm 199 floor 201 Ceiling Swivel Arm 203 Base 205 Ceiling Rail 211 Control Function 213 Image generation function 251 Display g1 Medical Imaging g2 display area ISC Isocenter z1, z2, z3, z4, z5, z6, z7 rotation axis

Claims

1. an X-ray tube that irradiates an object with X-rays; an X-ray detector including a first detector and a second detector having a smaller field of view than the first detector, and outputting a detection signal based on X-rays that have passed through the subject and are incident thereon; a designation unit that designates a plurality of positions in a first X-ray image generated based on a detection signal from the first detector; an image acquisition unit that moves at least one of the X-ray detector and a tabletop on which the subject is placed relatively to the subject so that the plurality of positions are included in a third X-ray image that is synthesized from the plurality of second X-ray images generated based on detection signals sequentially acquired by the second detector, and acquires the plurality of second X-ray images; a determination unit that determines a position of a stenosis portion of a blood vessel in the first X-ray image based on the first X-ray image, and determines a plurality of imaging positions for generating the plurality of second X-ray images based on the position of the stenosis portion, the position of the X-ray detector in generating the first X-ray image, the size of the small field of view, and the plurality of positions; the image acquisition unit sequentially moves at least one of the X-ray detector and the tabletop to the plurality of imaging positions to acquire the plurality of second X-ray images. X-ray diagnostic equipment.

2. the image acquisition unit moves at least one of the X-ray detector and the tabletop along at least one straight line passing through the plurality of positions from one end point to the other end point of the plurality of positions, to acquire the plurality of second X-ray images.

2. The X-ray diagnostic apparatus according to claim 1.

3. a determination unit that determines a plurality of imaging positions for generating the plurality of second X-ray images based on a position of the X-ray detector in generating the first X-ray image, a size of the small field of view, and the plurality of positions; the image acquisition unit sequentially moves at least one of the X-ray detector and the tabletop to the plurality of imaging positions to acquire the plurality of second X-ray images.

3. The X-ray diagnostic apparatus according to claim 1.

4. the determination unit further determines a position of a device located in the blood vessel based on the first X-ray image, and determines the plurality of imaging positions using the position of the device.

4. An X-ray diagnostic apparatus according to claim 1.

5. when the plurality of positions are included in a width of the small field of view along a direction perpendicular to a body axis direction of the subject in the first X-ray image, the image acquisition unit moves at least one of the X-ray detector and the tabletop along the body axis direction to acquire the plurality of second X-ray images.

5. An X-ray diagnostic apparatus according to claim 1.

6. the X-ray detector is rotatable about a rotation axis that is a straight line connecting the X-ray tube and the X-ray detector, when the plurality of positions are included in a width of the small field of view along a direction perpendicular to a body axis direction of the subject in the first X-ray image, the image acquisition unit rotates the X-ray detector according to an angle between a regression line for the plurality of positions and the body axis direction, and then translates the X-ray detector in a direction along the regression line to acquire the plurality of second X-ray images; a display unit that displays the third X-ray image by rotating the third X-ray image according to the angle so that the up-down direction of an image display area coincides with the body axis direction in the third X-ray image, 5. An X-ray diagnostic apparatus according to claim 1.

7. an X-ray detector including a first detector and a second detector having a smaller field of view than the first detector, the first X-ray image being generated based on a detection signal from the first detector; At least one of the X-ray detector and a tabletop on which the subject is placed is moved relative to the subject so that the plurality of positions are included in a third X-ray image synthesized from the plurality of second X-ray images generated based on detection signals sequentially collected by the second detector, and the plurality of second X-ray images are collected; determining a position of a stenosis portion of a blood vessel in the first X-ray image based on the first X-ray image; and determining a plurality of imaging positions for generating the plurality of second X-ray images based on the position of the stenosis portion, the position of the X-ray detector in generating the first X-ray image, the size of the small field of view, and the plurality of positions; and acquiring the plurality of second X-ray images by sequentially moving at least one of the X-ray detector and the tabletop to the plurality of imaging positions. X-ray image acquisition method.

Images