JP7553307B2 - X-ray diagnostic equipment - Google Patents

Description

An embodiment of the present invention relates to an X-ray diagnostic device.

Conventionally, various X-ray imaging methods are known that collect multiple projection data with different X-ray irradiation angles to obtain a reconstructed image. For example, tomosynthesis imaging may be performed in an examination that uses tomographic images (slices) of a subject. In tomosynthesis imaging, the X-ray tube irradiates the subject with X-rays while moving the X-ray tube on a predetermined trajectory. This allows multiple projection data to be collected with different X-ray irradiation angles for the subject, and multiple tomographic images to be reconstructed from the collected multiple projection data.

JP 2011-87917 A JP 2017-6244 A

The problem that this invention aims to solve is to make it easier to select a trajectory in X-ray photography.

The X-ray diagnostic apparatus of the embodiment includes an image acquisition unit, a trajectory designation unit, and an image processing unit. The image acquisition unit acquires a two-dimensional X-ray image of a subject captured in a first imaging session. The trajectory designation unit designates at least one trajectory along which an X-ray generating unit moves in a second imaging session performed after the first imaging session. The image processing unit performs a prediction process based on the two-dimensional X-ray image and the trajectory to predict artifacts that will occur when the second imaging session is performed on the trajectory.

FIG. 1 is a block diagram showing an example of the configuration of an X-ray diagnostic apparatus according to the first embodiment. FIG. 2A is a diagram showing an example of a trajectory of the X-ray tube according to the first embodiment. FIG. 2B is a diagram showing an example of a trajectory of the X-ray tube according to the first embodiment. FIG. 2C is a diagram showing an example of a trajectory of the X-ray tube according to the first embodiment. FIG. 3A is a diagram illustrating an example of a reconstruction process according to the first embodiment. FIG. 3B is a diagram showing an example of a tomographic image according to the first embodiment. FIG. 3C is a diagram showing an example of a tomographic image according to the first embodiment. FIG. 4A is a diagram illustrating an example of positioning of a subject according to the first embodiment. FIG. 4B is a diagram showing an example of a two-dimensional X-ray image according to the first embodiment. FIG. 5A is a diagram showing an example of a processed image according to the first embodiment. FIG. 5B is a diagram showing an example of a processed image according to the first embodiment. FIG. 5C is a diagram illustrating an example of a processed image according to the first embodiment. FIG. 5D is a diagram showing an example of a processed image according to the first embodiment. FIG. 6 is a flowchart for explaining a series of processing steps of the X-ray diagnostic apparatus according to the first embodiment. FIG. 7 is a diagram showing an input operation of the trajectory of the X-ray tube according to the second embodiment. FIG. 8 is a flowchart for explaining a series of processing steps of the X-ray diagnostic apparatus according to the second embodiment. FIG. 9 is a diagram illustrating an example of an angle range of a trajectory according to the third embodiment. FIG. 10A is a diagram showing an example of a processed image according to the third embodiment. FIG. 10B is a diagram showing an example of a processed image according to the third embodiment. FIG. 11 is a diagram showing an interference region according to the third embodiment. FIG. 12 is a block diagram showing an example of the configuration of an X-ray diagnostic apparatus according to the third embodiment. FIG. 13 is a block diagram showing an example of the configuration of a medical image processing apparatus according to the third embodiment.

The X-ray diagnostic device according to the embodiment will be described below with reference to the drawings.

First Embodiment
In the first embodiment, an X-ray diagnostic apparatus 1 shown in Fig. 1 will be described as an example. Fig. 1 is a block diagram showing an example of the configuration of the X-ray diagnostic apparatus 1 according to the first embodiment. As shown in Fig. 1, the X-ray diagnostic apparatus 1 includes an X-ray high voltage device 11, an X-ray tube 12, an X-ray aperture 13, a tabletop 14, a C-arm 15, an X-ray detector 16, a memory 17, a display 18, an input interface 19, and a processing circuit 20.

In this embodiment, tomosynthesis imaging will be described as an example of an X-ray imaging method for collecting multiple projection data with different X-ray irradiation angles. For ease of explanation, the longitudinal direction of the tabletop 14 is defined as the Z-axis direction. The direction perpendicular to the Z-axis direction and horizontal to the tabletop 14 is defined as the X-axis direction. The X-axis direction corresponds to the short side direction of the tabletop 14. The direction perpendicular to the Z-axis direction and perpendicular to the tabletop 14 is defined as the Y-axis direction.

The X-ray high voltage device 11 supplies a high voltage to the X-ray tube 12 under the control of the processing circuit 20. For example, the X-ray high voltage device 11 has electrical circuits such as a transformer and a rectifier, and includes a high voltage generator that generates a high voltage to be applied to the X-ray tube 12, and an X-ray control device that controls the output voltage according to the X-rays emitted by the X-ray tube 12. The high voltage generator may be of a transformer type or an inverter type.

The X-ray tube 12 is a vacuum tube that has a cathode (filament) that generates thermoelectrons and an anode (target) that generates X-rays when struck by the thermoelectrons. The X-ray tube 12 generates X-rays by irradiating thermoelectrons from the filament toward the target using a tube voltage supplied from the X-ray high voltage device 11. The X-ray tube 12 is an example of an X-ray generating unit.

The X-ray aperture 13 has a collimator that narrows the irradiation range of the X-rays generated by the X-ray tube 12, and a filter that adjusts the X-rays generated by the X-ray tube 12.

The collimator in the X-ray aperture 13 has, for example, four slidable aperture blades. By sliding the aperture blades, the collimator narrows the X-rays generated by the X-ray tube 12 and irradiates them on the subject P. Here, the aperture blades are plate-shaped members made of lead or the like, and are provided near the X-ray irradiation port of the X-ray tube 12 to adjust the irradiation range of the X-rays.

The filter in the X-ray aperture 13 changes the quality of the X-rays that pass through it depending on its material and thickness, in order to reduce the radiation dose to the subject P and improve the quality of the X-ray image, reducing the soft ray components that are easily absorbed by the subject P and the high energy components that reduce the contrast of the X-ray image. In addition, the filter changes the X-ray dose and irradiation range depending on its material, thickness, position, etc., and attenuates the X-rays so that the X-rays irradiated from the X-ray tube 12 to the subject P have a predetermined distribution.

For example, the X-ray aperture 13 has a driving mechanism such as a motor and an actuator, and controls the irradiation of X-rays by operating the driving mechanism under the control of the processing circuitry 20 described later. For example, the X-ray aperture 13 applies a driving voltage to the driving mechanism in response to a control signal received from the processing circuitry 20 to adjust the opening of the aperture blades of the collimator and control the irradiation range of the X-rays irradiated to the subject P. Also, for example, the X-ray aperture 13 applies a driving voltage to the driving mechanism in response to a control signal received from the processing circuitry 20 to adjust the position of the filter, thereby controlling the distribution of the X-ray dose irradiated to the subject P.

The tabletop 14 is a bed on which the subject P rests, and is placed on a bed drive device (not shown). Note that the subject P is not included in the X-ray diagnostic apparatus 1. For example, the bed drive device has a drive mechanism such as a motor and an actuator, and controls the movement and tilt of the tabletop 14 by operating the drive mechanism under the control of the processing circuitry 20 (described later). For example, the bed drive device moves and tilts the tabletop 14 by applying a drive voltage to the drive mechanism in response to a control signal received from the processing circuitry 20.

The C-arm 15 holds the X-ray tube 12, the X-ray aperture 13, and the X-ray detector 16 so that they face each other with the subject P in between. For example, the C-arm 15 has a driving mechanism such as a motor and an actuator, and rotates and moves by operating the driving mechanism under the control of the processing circuit 20 described later. For example, the C-arm 15 applies a driving voltage to the driving mechanism in response to a control signal received from the processing circuit 20, thereby rotating and moving the X-ray tube 12, the X-ray aperture 13, and the X-ray detector 16 relative to the subject P, and controlling the X-ray irradiation position and irradiation angle. Note that in FIG. 1, the X-ray diagnostic device 1 is described as being a single plane, but the embodiment is not limited to this and may be a biplane.

The C-arm 15 is also configured to be rotatable in multiple directions. For example, as shown in FIG. 1, the C-arm 15 is positioned so that the X-ray tube 12, the X-ray aperture 13, and the X-ray detector 16 sandwich the subject P from the +X direction. That is, the C-arm 15 is positioned on the side of the subject P. In this case, the C-arm 15 can rotate around the X-axis direction as the rotation axis or around the Z-axis direction as the rotation axis. Note that FIG. 1 is merely an example, and the position of the C-arm 15 relative to the subject P and the number and direction of the rotation axes of the C-arm 15 can be changed as desired.

The X-ray detector 16 is, for example, an X-ray flat panel detector (FPD) having detection elements arranged in a matrix. The X-ray detector 16 detects X-rays emitted from the X-ray tube 12 and transmitted through the subject P, and outputs a detection signal corresponding to the detected X-ray amount to the processing circuit 20. Here, the X-ray detector 16 may be an indirect conversion type detector having a grid, a scintillator array, and a photosensor array, or may be a direct conversion type detector having semiconductor elements that convert incident X-rays into electrical signals.

The memory 17 is realized by, for example, a semiconductor memory element such as a RAM (Random Access Memory), a flash memory, a hard disk, an optical disk, or the like. For example, the memory 17 accepts and stores various data collected by the processing circuit 20. The memory 17 also stores programs corresponding to various functions executed by the circuits included in the X-ray diagnostic apparatus 1. The memory 17 may also be realized by a group of servers (cloud) connected to the X-ray diagnostic apparatus 1 via a network. The memory 17 is also an example of a storage unit.

The display 18 displays various types of information. For example, under the control of the processing circuit 20, the display 18 displays a GUI (Graphical User Interface) and various images for receiving instructions from an operator. For example, the display 18 is a liquid crystal display or a CRT (Cathode Ray Tube) display. The display 18 may be a desktop type, or may be configured as a tablet terminal or the like capable of wireless communication with the processing circuit 20.

The input interface 19 receives various input operations from an operator, converts the received input operations into electrical signals, and outputs the electrical signals to the processing circuit 20. For example, the input interface 19 is realized by a mouse, a keyboard, a trackball, a switch, a button, a joystick, a touchpad that performs input operations by touching the operation surface, a touch screen in which a display screen and a touchpad are integrated, a non-contact input circuit using an optical sensor, a voice input circuit, and the like. The input interface 19 may be configured as a tablet terminal or the like that can wirelessly communicate with the processing circuit 20. The input interface 19 is not limited to only those that have physical operating parts such as a mouse and a keyboard. For example, an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the X-ray diagnostic apparatus 1 and outputs the electrical signal to the processing circuit 20 is also included as an example of the input interface 19.

The processing circuit 20 controls the operation of the entire X-ray diagnostic apparatus 1 by executing a control function 201, a reception function 202, an image processing function 203, and a display control function 204. Here, the control function 201 is an example of a control unit. The reception function 202 is an example of a reception unit. The image processing function 203 is an example of an image acquisition unit, a trajectory designation unit, and an image processing unit. The display control function 204 is an example of a display control unit.

For example, the processing circuit 20 reads out a program corresponding to the control function 201 from the memory 17 and executes it to control various functions of the processing circuit 20. The control function 201 also controls the X-ray high voltage device 11 to supply a tube voltage to the X-ray tube 12, causing the X-ray tube 12 to generate X-rays. The control function 201 also controls the operation of the X-ray aperture 13, and adjusts the opening of the aperture blades of the collimator to narrow the irradiation range of the X-rays generated by the X-ray tube 12. The control function 201 also controls the operation of the X-ray aperture 13, and adjusts the position of the filter to control the distribution of the X-ray dose. The control function 201 also controls the operation of the C-arm 15, and rotates and moves the C-arm 15 to control the irradiation position and irradiation angle of the X-rays. The control function 201 also controls the operation of the bed drive device, and moves and tilts the top board 14 to control the irradiation position and irradiation angle of the X-rays.

The control function 201 can perform various types of imaging by controlling the operation of the X-ray high voltage device 11, X-ray tube 12, X-ray aperture 13, tabletop 14, C-arm 15, and X-ray detector 16. For example, the control function 201 collects multiple projection data by irradiating X-rays from the X-ray tube 12 onto the subject P while changing the X-ray irradiation angle by controlling the operation of the C-arm 15. That is, the control function 201 performs tomosynthesis imaging of the subject P. Note that tomosynthesis imaging by the control function 201 will be described later.

The processing circuit 20 also reads out from the memory 17 a program corresponding to the reception function 202 and executes it to receive various input operations from the operator via the input interface 19. For example, the reception function 202 receives input operations of shooting conditions from the operator. The input operations received by the reception function 202 will be described later.

The processing circuit 20 also generates a two-dimensional X-ray image based on the detection signal output from the X-ray detector 16 by reading out a program corresponding to the image processing function 203 from the memory 17 and executing it, and stores the generated X-ray image in the memory 17. That is, the image processing function 203 acquires a two-dimensional X-ray image. The image processing function 203 also specifies at least one trajectory along which the X-ray tube 12 moves in tomosynthesis imaging. The image processing function 203 also performs prediction processing to predict artifacts that will occur when the second imaging is performed on the specified trajectory. For example, the image processing function 203 performs image processing on the two-dimensional X-ray image according to the trajectory of the X-ray tube 12 in tomosynthesis imaging, thereby generating a processed image as a result of the prediction processing. The prediction processing by the image processing function 203 will be described later.

In addition, in tomosynthesis imaging, the image processing function 203 generates multiple pieces of projection data based on the detection signal output from the X-ray detector 16, and stores the generated multiple pieces of projection data in the memory 17. In addition, the image processing function 203 reconstructs multiple tomographic images based on the multiple pieces of projection data. The process of generating the tomographic images by the image processing function 203 will be described later.

The processing circuit 20 also reads out a program corresponding to the display control function 204 from the memory 17 and executes it to display various information on the display 18. For example, the display control function 204 displays a GUI for receiving instructions from an operator on the display 18. The display control function 204 also displays the results of prediction processing by the image processing function 203 on the display 18. As an example, the display control function 204 displays the processed image generated by the image processing function 203 on the display 18. The control function 201 also controls the transmission and reception of data between the X-ray diagnostic apparatus 1 and other devices. For example, the control function 201 transmits various images generated by the image processing function 203 to an image storage device (not shown).

In the X-ray diagnostic apparatus 1 shown in FIG. 1, each processing function is stored in the memory 17 in the form of a program executable by a computer. The processing circuit 20 is a processor that realizes the function corresponding to each program by reading and executing the program from the memory 17. In other words, the processing circuit 20 in a state in which a program has been read has the function corresponding to the read program. Note that in FIG. 1, the control function 201, the reception function 202, the image processing function 203, and the display control function 204 are realized by a single processing circuit 20, but the processing circuit 20 may be configured by combining multiple independent processors, and each processor may realize the function by executing a program. In addition, each processing function of the processing circuit 20 may be realized by being appropriately distributed or integrated into a single or multiple processing circuits.

The term "processor" used in the above description refers to circuits such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an Application Specific Integrated Circuit (ASIC), a programmable logic device (e.g., a Simple Programmable Logic Device (SPLD), a Complex Programmable Logic Device (CPLD), and a Field Programmable Gate Array (FPGA)). The processor achieves its functions by reading and executing a program stored in memory 17.

In FIG. 1, a single memory 17 is described as storing a program corresponding to each processing function. However, the embodiment is not limited to this. For example, a plurality of memories 17 may be distributed and the processing circuit 20 may be configured to read out the corresponding program from each individual memory 17. Also, instead of storing the program in the memory 17, the program may be directly built into the circuit of the processor. In this case, the processor realizes the function by reading and executing the program built into the circuit.

The processing circuitry 20 may also realize functions by using a processor of an external device connected via a network. For example, the processing circuitry 20 reads out and executes a program corresponding to each function from the memory 17, and realizes each function shown in FIG. 1 by using a group of servers (cloud) connected to the X-ray diagnostic apparatus 1 via a network as a computing resource.

The overall configuration of the X-ray diagnostic apparatus 1 has been described above. With this configuration, the X-ray diagnostic apparatus 1 according to the first embodiment facilitates the selection of a trajectory in tomosynthesis imaging through processing by the processing circuitry 20.

First, an example of tomosynthesis imaging performed by the X-ray diagnostic apparatus 1 will be described. When performing tomosynthesis imaging, the control function 201 first sets various imaging conditions related to tomosynthesis imaging. Here, imaging conditions related to tomosynthesis imaging include, for example, the trajectory of the X-ray tube 12, the X-ray dose, and the frame rate. As an example, the operator performs an input operation of imaging conditions via the input interface 19 based on the examination information of the subject P. In addition, the reception function 202 accepts the input operation of imaging conditions by the operator. In addition, the control function 201 sets the imaging conditions based on the input operation accepted by the reception function 202.

Here, the trajectory of the X-ray tube 12 in tomosynthesis imaging will be described with reference to FIG. 2A. FIG. 2A is a diagram showing an example of the trajectory of the X-ray tube 12 according to the first embodiment. For example, as shown in FIG. 2A, the control function 201 sets the trajectory T11 on the XZ plane as the imaging condition. Note that the trajectory T11 is a linear trajectory along the X-axis direction. After setting the imaging condition, the control function 201 performs tomosynthesis imaging by moving the X-ray tube 12 along the trajectory T11 while irradiating X-rays from the X-ray tube 12 to the subject P.

For example, the control function 201 rotates the C-arm 15 to move the X-ray tube 12 along the trajectory T11. As an example, the control function 201 first rotates and moves the C-arm 15 to place the X-ray tube 12 at position X1 shown in FIG. 2B, and to make the X-ray tube 12 and the X-ray detector 16 face each other across the subject P. Next, the control function 201 rotates the C-arm 15 around the Z-axis as the rotation axis. As a result, the X-ray tube 12 moves along the trajectory T11 to position X2 shown in FIG. 2C. At this time, as shown in FIG. 2B and FIG. 2C, the irradiation angle of the X-ray changes with the change in the position of the X-ray tube 12. Note that FIG. 2B and FIG. 2C are diagrams showing an example of the trajectory of the X-ray tube 12 according to the first embodiment.

When the X-ray tube 12 is moved by rotating the C-arm 15, as shown in Figures 2B and 2C, the X-ray tube 12 moves along a curve that includes changes in the Y-axis direction. However, when viewed from the Y-axis direction, this curve appears as a straight line along the X-axis direction. In other words, the control function 201 can move the X-ray tube 12 along the trajectory T11 set in the XZ plane by rotating the C-arm 15.

The control function 201 also controls the supply of tube voltage from the X-ray high voltage device 11 to the X-ray tube 12 while moving the X-ray tube 12 along the trajectory T11, and repeatedly irradiates the subject P with X-ray pulses according to the set frame rate. That is, the control function 201 repeatedly irradiates the subject P with X-ray pulses while changing the X-ray irradiation angle. Here, the X-ray detector 16 detects the X-rays that have passed through the subject P, and outputs a detection signal corresponding to the detected X-ray amount to the processing circuit 20. The image processing function 203 also generates projection data based on the detection signal output from the X-ray detector 16. That is, the image processing function 203 generates multiple projection data with the X-ray irradiation angle changed.

Next, the image processing function 203 reconstructs multiple tomographic images based on the multiple projection data. For example, the image processing function 203 first performs various image processing on the multiple projection data. As an example, the image processing function 203 removes DC components (direct current components) from the multiple projection data. Then, the image processing function 203 performs back projection processing by the FBP (Filtered Back Projection) method on the multiple projection data after processing, thereby reconstructing multiple tomographic images parallel to the XZ plane, as shown in FIG. 3A. That is, the image processing function 203 reconstructs multiple tomographic images with the reconstruction plane shifted in the Y-axis direction based on the multiple projection data. Note that FIG. 3A is a diagram showing an example of reconstruction processing according to the first embodiment.

The display control function 204 displays the multiple tomographic images reconstructed by the image processing function 203. For example, the display control function 204 displays one of the multiple tomographic images on the display 18, or displays the multiple tomographic images sequentially. As an example, the display control function 204 displays the tomographic image B1 shown in FIG. 3B and the tomographic image B2 shown in FIG. 3C on the display 18. Note that FIGS. 3B and 3C are diagrams showing examples of tomographic images according to the first embodiment.

For example, when the area R1 shown in FIG. 3B is the area to be inspected, the display control function 204 causes the display 18 to display the tomographic image B1. Also, when the area R2 shown in FIG. 3C is the area to be inspected, the display control function 204 causes the display 18 to display the tomographic image B2. This allows the operator to observe the area to be inspected by focusing on the tomographic image in which the area to be inspected appears.

As shown in Figures 3B and 3C, the tomographic image reconstructed by the image processing function 203 may contain artifacts. Specifically, when the X-ray absorption rate of the parts R1 and R2 is high (such as when the parts R1 and R2 are bone or metal), artifacts extending in a direction corresponding to the trajectory of the X-ray tube 12 are generated around the parts R1 and R2. For example, when tomosynthesis imaging is performed using a linear trajectory T11 along the X-axis direction, artifacts extending in the X-axis direction from the parts R1 and R2 are generated as shown in Figures 3B and 3C. Such artifacts are also referred to as shadow defects.

Depending on the direction in which the artifact occurs, it may interfere with observation of the area to be examined. For example, when the area R1 shown in FIG. 3B is the area to be examined and a tomographic image B1 is displayed, if attention is paid to position C1 around the area R1, the artifact shown in FIG. 3B interferes with observation. On the other hand, if attention is paid to position C2 around the area R1, the artifact shown in FIG. 3B does not interfere with observation. Here, since the artifact occurs in a direction according to the trajectory of the X-ray tube 12, by appropriately selecting the trajectory of the X-ray tube 12, it is possible to avoid a situation in which the artifact interferes with observation. However, it is not easy to predict the artifacts that will occur and appropriately select the trajectory of the X-ray tube 12 at the stage of setting the imaging conditions.

The X-ray diagnostic apparatus 1 according to the first embodiment specifies at least one trajectory along which the X-ray tube 12 moves in tomosynthesis imaging, and performs a prediction process to predict artifacts that will occur when tomosynthesis imaging is performed on the specified trajectory based on two-dimensional X-ray images previously collected from the subject P and the specified trajectory, thereby facilitating the selection of a trajectory in tomosynthesis imaging. Specifically, the X-ray diagnostic apparatus 1 generates a processed image by performing image processing according to the trajectory of the X-ray tube 12 on two-dimensional X-ray images previously collected from the subject P, and displays the generated processed image, thereby facilitating the selection of a trajectory in tomosynthesis imaging. This point will be described in detail below.

First, the image processing function 203 acquires a two-dimensional X-ray image collected in advance from the subject P. That is, the image processing function 203 acquires a two-dimensional X-ray image collected from the subject P before performing tomosynthesis imaging. As an example, the image processing function 203 acquires an X-ray image collected for positioning the subject P before performing tomosynthesis imaging as a two-dimensional X-ray image collected in advance from the subject P. The imaging performed for positioning is an example of the first imaging. Also, the tomosynthesis imaging performed after the first imaging is an example of the second imaging.

Now, the positioning of the subject P will be described with reference to FIG. 4A. FIG. 4A is a diagram showing an example of the positioning of the subject P according to the first embodiment. First, the control function 201 rotates and moves the C-arm 15 to place the X-ray tube 12 at position X3 shown in FIG. 4A, and opposes the X-ray tube 12 and the X-ray detector 16 so as to sandwich the subject P from the Y-axis direction. As a result, the control function 201 controls the X-ray irradiation angle to match the Y-axis direction. That is, the control function 201 places the X-ray tube 12 at the acquisition reference position for tomosynthesis imaging.

Next, the control function 201 irradiates the subject P with X-rays in the arrangement shown in FIG. 4A. For example, the control function 201 controls the supply of tube voltage from the X-ray high voltage device 11 to the X-ray tube 12, thereby repeatedly irradiating the subject P with X-ray pulses. Here, the X-ray detector 16 detects X-rays that have passed through the subject P, and outputs a detection signal corresponding to the detected X-ray amount to the processing circuit 20. The image processing function 203 generates an X-ray image based on the detection signal output from the X-ray detector 16. For example, the image processing function 203 generates X-ray images sequentially each time the subject P is irradiated with an X-ray pulse. The display control function 204 displays the generated X-ray images sequentially on the display 18 each time an X-ray image is generated. In the following, the X-ray images displayed sequentially in parallel with the irradiation of X-rays are referred to as fluoroscopic images.

The operator refers to the fluoroscopic image displayed on the display 18 and determines whether or not the area to be examined is included in the fluoroscopic image. If the area to be examined is not included in the fluoroscopic image, the control function 201, under input operations by the operator, changes the position of the tabletop 14 or the C-arm 15 so that the area to be examined is included in the fluoroscopic image. On the other hand, if the area to be examined is included in the fluoroscopic image, the control function 201 ends positioning of the subject P.

The image processing function 203 also acquires the last fluoroscopic image collected during positioning of the subject P as a two-dimensional X-ray image. That is, the image processing function 203 acquires the last image hold (LIH) as a two-dimensional X-ray image. Here, as an example, the two-dimensional X-ray image I1 is shown in FIG. 4B. As shown in FIG. 4B, the two-dimensional X-ray image I1 is an image that includes both the part R1 and the part R2. That is, unlike the tomographic images (tomographic images B1, B2, etc.) obtained by tomosynthesis imaging, the two-dimensional X-ray image I1 is an image that includes multiple parts at different positions in the Y-axis direction. Note that FIG. 4B is a diagram showing an example of the two-dimensional X-ray image I1 according to the first embodiment.

Next, the image processing function 203 performs image processing on the two-dimensional X-ray image I1 according to the trajectory of the X-ray tube 12. For example, the image processing function 203 performs image processing on the two-dimensional X-ray image I1 according to the trajectory T11 to generate a processed image I21 shown in FIG. 5A. Such image processing is performed based on, for example, a pre-set image processing setting. As an example, the memory 17 stores a kernel used for the filter processing as an image processing setting corresponding to the trajectory T11. Then, the image processing function 203 reads out a kernel from the memory 17 according to the trajectory T11, and performs filter processing on the two-dimensional X-ray image I1 using the read out kernel to generate the processed image I21 shown in FIG. 5A. In addition, the display control function 204 causes the display 18 to display the generated processed image I21. FIG. 5A is a diagram showing an example of a processed image according to the first embodiment.

For example, trajectory T11 is a preset trajectory and is stored in memory 17. The image processing function 203 can read out trajectory T11 from memory 17 and specify it as the trajectory along which the X-ray tube 12 moves in tomosynthesis imaging. The same applies to trajectory T12, trajectory T13, trajectory T14, etc., which will be described later.

As shown in FIG. 5A, in the processed image I21, shadows are generated around the parts R1 and R2, similar to the tomographic images shown in FIG. 3B and FIG. 3C. That is, the processed image I21 is a prediction of artifacts that will occur in a tomographic image obtained by tomosynthesis imaging. That is, the image processing shown in FIG. 5A is a prediction process that predicts artifacts that will occur when tomosynthesis imaging is performed on the trajectory T11, based on a two-dimensional X-ray image and the trajectory T11. Moreover, the processed image I21 is an example of the result of the prediction process.

The processed image I21 allows the operator to determine whether or not trajectory T11 is appropriate as the trajectory of the X-ray tube 12. For example, when focusing on position C1 around region R1, the operator can determine that trajectory T11 is not appropriate because the artifacts predicted in processed image I21 interfere with observation. Also, when focusing on position C2 around region R1, the operator can determine that trajectory T11 is appropriate because the artifacts predicted in processed image I22 do not interfere with observation. That is, the operator can easily determine whether trajectory T11 is appropriate based on processed image I21.

The display control function 204 may display a trajectory T11 corresponding to the processed image I21 in addition to the processed image I21. For example, the display control function 204 illustrates the trajectory T11 as viewed from the Y-axis direction. As an example, the display control function 204 illustrates the position and orientation of the trajectory T11 relative to the tabletop 14, as shown in the upper diagram of FIG. 5A.

The display control function 204 may also display the acquisition time corresponding to the processed image I21 in addition to the processed image I21. That is, the display control function 204 may display the acquisition time required to acquire multiple projection data when performing tomosynthesis imaging based on the trajectory T11 corresponding to the processed image I21. For example, the display control function 204 displays "4 seconds" as the acquisition time, as shown in the upper diagram of FIG. 5A.

Similarly, the image processing function 203 performs image processing according to the trajectory T12 shown in FIG. 5B on the two-dimensional X-ray image I1 to generate a processed image I22. Note that the trajectory T12 is a linear trajectory along the Z-axis direction, and when tomosynthesis imaging is performed using the trajectory T12, artifacts extending in the Z-axis direction are generated in the tomographic image. For example, the image processing function 203 reads out a kernel according to the trajectory T12 from the memory 17, and uses the read out kernel to perform filter processing on the two-dimensional X-ray image I1 to generate a processed image I22. The display control function 204 also displays the generated processed image I22 on the display 18. Note that FIG. 5B is a diagram showing an example of a processed image according to the first embodiment.

The processed image I22 allows the operator to determine whether or not trajectory T12 is appropriate as the trajectory of the X-ray tube 12. For example, when focusing on position C1 around region R1, the operator can determine that trajectory T12 is appropriate because the artifacts predicted in the processed image I22 do not interfere with observation. Also, for example, when focusing on position C2 around region R1, the artifacts predicted in the processed image I22 interfere with observation, so the operator can determine that trajectory T12 is not appropriate. That is, the operator can easily determine whether or not trajectory T12 is appropriate based on the processed image I22.

The display control function 204 may display a trajectory T12 corresponding to the processed image I22 in addition to the processed image I22. For example, the display control function 204 illustrates the trajectory T12 as viewed from the Y-axis direction as shown in the upper diagram of FIG. 5B. The display control function 204 may display a collection time corresponding to the processed image I22 in addition to the processed image I22. For example, the display control function 204 displays "4 seconds" as the collection time as shown in the upper diagram of FIG. 5B.

Similarly, the image processing function 203 generates a processed image I23 by performing image processing according to the trajectory T13 shown in FIG. 5C on the two-dimensional X-ray image I1. The trajectory T13 is an eight-shaped trajectory that is long in the X-axis direction. When tomosynthesis imaging is performed using the trajectory T13, artifacts extending in the X-axis direction occur in the tomographic image because the trajectory T13 is long in the X-axis direction. However, since the trajectory T13 also includes movement in the Z-axis direction, the artifacts are reduced compared to when tomosynthesis imaging is performed using the trajectory T11. For example, the image processing function 203 reads out a kernel corresponding to the trajectory T13 from the memory 17 and performs filter processing on the two-dimensional X-ray image I1 using the read kernel to generate a processed image I23. The display control function 204 also displays the generated processed image I23 on the display 18. FIG. 5C is a diagram showing an example of a processed image according to the first embodiment.

The processed image I23 allows the operator to determine whether or not trajectory T13 is appropriate as the trajectory of the X-ray tube 12. For example, if position C2 is more attention-grabbing than position C1, the artifacts predicted in the processed image I23 may interfere with the observation of position C1 but will not interfere with the observation of position C2, so the operator can determine that trajectory T13 is appropriate. Also, for example, if position C1 is more attention-grabbing than position C2, the artifacts predicted in the processed image I23 may interfere with the observation of position C1, so the operator can determine that trajectory T13 is not appropriate. That is, the operator can easily determine whether trajectory T13 is appropriate based on the processed image I23.

The display control function 204 may display a trajectory T13 corresponding to the processed image I23 in addition to the processed image I23. For example, the display control function 204 illustrates the trajectory T13 as viewed from the Y-axis direction as shown in the upper diagram of FIG. 5C. The display control function 204 may display the collection time corresponding to the processed image I23 in addition to the processed image I23. For example, the display control function 204 displays "8 seconds" as the collection time as shown in the upper diagram of FIG. 5C.

Similarly, the image processing function 203 generates a processed image I24 by performing image processing according to the trajectory T14 shown in FIG. 5D on the two-dimensional X-ray image I1. The trajectory T14 is an eight-shaped trajectory that is long in the Z-axis direction. When tomosynthesis imaging is performed using the trajectory T14, artifacts extending in the Z-axis direction occur in the tomographic image because the trajectory T14 is long in the Z-axis direction. However, since the trajectory T14 also includes movement in the X-axis direction, the artifacts are reduced compared to when tomosynthesis imaging is performed using the trajectory T12. For example, the image processing function 203 reads out a kernel corresponding to the trajectory T14 from the memory 17 and performs filter processing on the two-dimensional X-ray image I1 using the read kernel to generate a processed image I24. The display control function 204 also displays the generated processed image I24 on the display 18. FIG. 5D is a diagram showing an example of a processed image according to the first embodiment.

The processed image I24 allows the operator to determine whether or not trajectory T14 is appropriate as the trajectory of the X-ray tube 12. For example, if position C2 is more attention-grabbing than position C1, the artifacts predicted in the processed image I24 will not interfere with the observation of position C1, but may interfere with the observation of position C2, so the operator can determine that trajectory T14 is not appropriate. Also, for example, if position C1 is more attention-grabbing than position C2, the artifacts predicted in the processed image I24 will not interfere with the observation of position C1, so the operator can determine that trajectory T14 is appropriate. That is, the operator can easily determine whether trajectory T14 is appropriate based on the processed image I24.

The display control function 204 may display a trajectory T14 corresponding to the processed image I24 in addition to the processed image I24. For example, the display control function 204 illustrates the trajectory T14 as viewed from the Y-axis direction as shown in the upper diagram of FIG. 5D. The display control function 204 may display the collection time corresponding to the processed image I24 in addition to the processed image I24. For example, the display control function 204 displays "8 seconds" as the collection time as shown in the upper diagram of FIG. 5D.

For example, the image processing function 203 performs image processing according to trajectory T11, image processing according to trajectory T12, image processing according to trajectory T13, and image processing according to trajectory T14 on the two-dimensional X-ray image I1 to generate processed images I21, I22, I23, and I24, respectively. That is, the image processing function 203 performs image processing according to multiple trajectories on the two-dimensional X-ray image I1 to generate multiple processed images. In addition, the display control function 204 displays the processed images I21, I22, I23, and I24 on the display 18. For example, the display control function 204 displays multiple processed images in parallel, or switches between the processed images in response to an input operation from the operator.

Next, the reception function 202 receives an operation from the operator to select one of the multiple processed images, and the control function 201 sets the trajectory corresponding to the selected processed image as the imaging condition. Here, the operator can easily select an appropriate processed image while referring to the artifacts predicted in each processed image. In other words, the operator can easily select a trajectory for tomosynthesis imaging based on the processed images.

After various imaging conditions (the trajectory of the X-ray tube 12, the X-ray dose, the frame rate, etc.) related to the tomosynthesis imaging are set, the control function 201 executes the tomosynthesis imaging based on the set imaging conditions. Specifically, the control function 201 moves the X-ray tube 12 along the set trajectory and causes the X-ray tube 12 to irradiate the subject P with X-rays. The image processing function 203 generates multiple projection data based on the detection signal output from the X-ray detector 16, and reconstructs multiple tomographic images based on the multiple projection data. The display control function 204 then displays the multiple tomographic images reconstructed by the image processing function 203 on the display 18. Here, although the displayed tomographic image may contain artifacts according to the trajectory of the X-ray tube 12, the trajectory of the X-ray tube 12 is appropriately selected based on the processed image, so that it is possible to avoid a situation in which artifacts interfere with observation.

Next, an example of the processing procedure by the X-ray diagnostic apparatus 1 will be described with reference to FIG. 6. FIG. 6 is a flowchart for explaining a series of processing flows of the X-ray diagnostic apparatus 1 according to the first embodiment. Steps S105, S106, and S109 correspond to the control function 201. Step S104 corresponds to the reception function 202. Steps S101, S102, and S107 correspond to the image processing function 203. Steps S103 and S108 correspond to the display control function 204.

First, the processing circuitry 20 acquires a two-dimensional X-ray image I1 previously collected from the subject P (step S101). Next, the processing circuitry 20 generates a plurality of processed images by performing a plurality of image processes corresponding to a plurality of trajectories on the two-dimensional X-ray image I1 (step S102). Next, the processing circuitry 20 displays the generated plurality of processed images on the display 18 (step S103).

The processing circuitry 20 then determines whether or not an operation to select one of the multiple processed images has been received (step S104), and goes into a standby state if a selection operation has not been received (step S104: No). On the other hand, if a selection operation has been received (step S104: Yes), the processing circuitry 20 sets the trajectory corresponding to the selected processed image as the shooting condition (step S105).

Next, the processing circuitry 20 performs tomosynthesis imaging according to the set imaging conditions (step S106). The processing circuitry 20 also reconstructs multiple tomographic images from multiple projection data collected by tomosynthesis imaging (step S107) and displays the reconstructed tomographic images on the display 18 (step S108). Here, the processing circuitry 20 determines whether or not to end the examination (step S109), and if it is determined that the examination should not be ended (step S109: No), it enters a standby state. On the other hand, if it is determined that the examination should be ended (step S109: Yes), the processing circuitry 20 ends the processing.

As described above, according to the first embodiment, the X-ray tube 12 irradiates the subject P with X-rays. The control function 201 controls the X-ray tube 12 to move relative to the subject P and irradiate X-rays from multiple positions, thereby performing tomosynthesis imaging. The image processing function 203 performs image processing according to the trajectory of the X-ray tube 12 on a two-dimensional X-ray image I1 of the subject P collected in advance, thereby generating a processed image. The display control function 204 displays the generated processed image. Therefore, the X-ray diagnostic apparatus 1 according to the first embodiment can easily select a trajectory in tomosynthesis imaging.

As described above, according to the first embodiment, the display control function 204 displays, in addition to the processed image, the acquisition time when performing tomosynthesis imaging based on the trajectory corresponding to the processed image. Therefore, according to the X-ray diagnostic apparatus 1 according to the first embodiment, it is possible to more appropriately select a trajectory for tomosynthesis imaging, taking into account the acquisition time.

As described above, according to the first embodiment, the image processing function 203 acquires a fluoroscopic image of the subject P as a two-dimensional X-ray image I1, and generates a processed image by performing image processing on the acquired fluoroscopic image according to the trajectory of the X-ray tube 12. That is, the image processing function 203 can acquire a two-dimensional X-ray image I1 and generate a processed image without performing additional imaging. Therefore, according to the X-ray diagnostic apparatus 1 according to the first embodiment, the radiation dose to which the subject P is exposed can be reduced.

Second Embodiment
In the above-described first embodiment, a case has been described in which a plurality of processed images based on a two-dimensional X-ray image are displayed and an operation to select one of the plurality of processed images is received, thereby setting the trajectory of the X-ray tube 12 in tomosynthesis imaging. In contrast, in the second embodiment, a case will be described in which an input operation of the trajectory of the X-ray tube 12 is received, and a processed image corresponding to the received trajectory is displayed.

The X-ray diagnostic apparatus 1 according to the second embodiment has a similar configuration to the X-ray diagnostic apparatus 1 according to the first embodiment shown in FIG. 1, with some differences in the processing by the reception function 202 and the image processing function 203. The same reference numerals as in FIG. 1 are used for the components having the same configuration as those described in the first embodiment, and the description thereof will be omitted.

First, the image processing function 203 acquires a two-dimensional X-ray image I1 that has been collected in advance from the subject P. For example, the image processing function 203 acquires a fluoroscopic image collected during positioning of the subject P as the two-dimensional X-ray image I1. Next, the display control function 204 causes the display 18 to display the two-dimensional X-ray image I1 acquired by the image processing function 203.

Here, the reception function 202 receives an input operation of the trajectory of the X-ray tube 12 from the operator who has referred to the two-dimensional X-ray image I1. For example, the reception function 202 receives an operation of setting a trajectory T21 on the two-dimensional X-ray image I1 as shown in FIG. 7. As an example, the operator specifies two points on the two-dimensional X-ray image I1, and the reception function 202 receives the straight line connecting the specified two points as the trajectory T21. Furthermore, based on the input operation received by the reception function 202, the image processing function 203 specifies the trajectory T21 as the trajectory along which the X-ray tube 12 moves in tomosynthesis imaging. Note that FIG. 7 is a diagram showing an input operation of the trajectory of the X-ray tube 12 according to the second embodiment.

For example, while referring to the two-dimensional X-ray image I1, the operator inputs a trajectory T21 that follows an edge of interest in region R1 or region R2. That is, since artifacts that appear in a tomographic image occur in a direction along the trajectory of the X-ray tube 12, typically no artifacts occur at edges along the trajectory of the X-ray tube 12 in region R1 or region R2. Therefore, by performing tomosynthesis imaging on a trajectory that follows the edge of interest, it is possible to avoid a situation in which the edge of interest becomes difficult to observe due to artifacts.

Next, the image processing function 203 performs image processing on the two-dimensional X-ray image I1 according to the trajectory T21 accepted by the acceptance function 202. For example, the image processing function 203 reads image processing settings from the memory 17 according to the trajectory T21, and performs image processing on the two-dimensional X-ray image I1 based on the read image processing settings. As a result, the image processing function 203 generates a processed image I25 (not shown).

If the memory 17 does not store image processing settings corresponding to the trajectory T21, the image processing function 203 may read and synthesize a plurality of image processing settings, and perform image processing based on the synthesized image processing settings on the two-dimensional X-ray image I1. For example, as shown in FIG. 7, the trajectory T21 is a straight line that intersects with the X-axis direction and the Z-axis direction at an angle of approximately 45 degrees. That is, the trajectory T21 is a straight line in the middle direction between the X-axis direction and the Z-axis direction. Therefore, the image processing function 203 reads and synthesizes an image processing setting corresponding to a linear trajectory (trajectory T11, etc.) along the X-axis direction and an image processing setting corresponding to a linear trajectory (trajectory T12, etc.) along the Z-axis direction. Then, the image processing function 203 performs image processing based on the synthesized image processing settings on the two-dimensional X-ray image I1 to generate a processed image I25.

Next, the display control function 204 displays the generated processed image I25 on the display 18. Here, if a trajectory along the edge of interest is input as the trajectory T21, typically the artifacts predicted in the processed image I25 do not occur at the edge of interest. Then, if no artifacts occur at the edge of interest in the processed image I25, the operator can determine that the trajectory T21 is appropriate. In this case, the control function 201 sets the trajectory T21 as the shooting condition.

On the other hand, it is also possible that an artifact may occur at the edge of interest, such as when multiple edges are adjacent. In such a case, the operator can determine that the trajectory T21 is inappropriate based on the processed image I25, and perform the input operation of the trajectory of the X-ray tube 12 again. Here, the reception function 202 receives the input operation of the trajectory of the X-ray tube 12 again. Furthermore, the image processing function 203 specifies the trajectory again based on the input operation received by the reception function 202. Furthermore, the image processing function 203 generates a processed image again by executing image processing on the two-dimensional X-ray image I1 according to the trajectory specified again. Then, the display control function 204 causes the display 18 to display the processed image generated again.

Alternatively, if the operator determines that trajectory T21 is not appropriate, the display control function 204 displays multiple processed images (processed image I21, processed image I22, processed image I23, processed image I24, etc.). Here, the display control function 204 may display multiple processed images instead of processed image I25, or may display multiple processed images in addition to processed image I25. Then, the reception function 202 receives an operation to select one of the multiple processed images displayed by the display control function 204, and the control function 201 sets the trajectory corresponding to the selected processed image as the shooting condition.

Next, an example of the processing procedure by the X-ray diagnostic apparatus 1 will be described with reference to FIG. 8. FIG. 8 is a flowchart for explaining a series of processing flows of the X-ray diagnostic apparatus 1 according to the second embodiment. Steps S206, S207, and S210 correspond to the control function 201. Steps S202 and S205 correspond to the reception function 202. Steps S201, S203, and S208 correspond to the image processing function 203. Steps S204 and S209 correspond to the display control function 204.

First, the processing circuitry 20 acquires a two-dimensional X-ray image previously collected from the subject P (step S201). Next, the processing circuitry 20 accepts an input operation of the trajectory of the X-ray tube 12 (step S202), specifies a trajectory based on the accepted input operation, and performs image processing according to the specified trajectory on the two-dimensional X-ray image to generate a processed image (step S203). Next, the processing circuitry 20 displays the generated processed image on the display 18 (step S204).

Next, the processing circuitry 20 determines whether or not an input operation to change the trajectory has been received from an operator who has referred to the processed image (step S205). If an input operation to change the trajectory has been received, the processing circuitry 20 again proceeds to step S202. On the other hand, if an input operation to change the trajectory has not been received, the processing circuitry 20 sets the trajectory received in step S202 as the shooting condition (step S206).

Next, the processing circuitry 20 performs tomosynthesis imaging according to the set imaging conditions (step S207). The processing circuitry 20 also reconstructs multiple tomographic images from multiple projection data collected by tomosynthesis imaging (step S208), and displays the reconstructed tomographic images on the display 18 (step S209). Here, the processing circuitry 20 determines whether or not to end the examination (step S210), and if it is determined that the examination should not be ended (step S210: No), it enters a standby state. On the other hand, if it is determined that the examination should be ended (step S210: Yes), the processing circuitry 20 ends the process.

As described above, the reception function 202 according to the second embodiment receives an input operation for the trajectory of the X-ray tube 12. The image processing function 203 specifies a trajectory based on the input operation received by the reception function 202. The image processing function 203 also generates a processed image by performing image processing on the two-dimensional X-ray image according to the specified trajectory. Therefore, the X-ray diagnostic apparatus 1 according to the second embodiment can indicate whether the trajectory desired by the operator is appropriate using the processed image, and can assist in the selection of a trajectory in tomosynthesis imaging.

Although the above describes a case where a trajectory is specified based on an input operation received by the reception function 202, various modifications are possible regarding the method of specifying a trajectory. For example, the image processing function 203 can also specify a trajectory based on a two-dimensional X-ray image I1. As one example, the image processing function 203 extracts an area R1 from the two-dimensional X-ray image I1, and specifies a trajectory along the edge of the area R1.

Third Embodiment
Although the first and second embodiments have been described above, the present invention may be embodied in various different forms other than the above-described embodiments.

In the above-described embodiment, the case where image processing is performed according to the shape of the trajectory of the X-ray tube 12 has been described. For example, FIG. 5A describes a case where image processing is performed according to a linear trajectory T11 along the X-axis direction, FIG. 5B describes a case where image processing is performed according to a linear trajectory T12 along the Z-axis direction, FIG. 5C describes a case where image processing is performed according to an eight-shaped trajectory T13 that is long in the X-axis direction, and FIG. 5D describes a case where image processing is performed according to an eight-shaped trajectory T14 that is long in the Z-axis direction. However, the embodiment is not limited to this. For example, the image processing function 203 may perform image processing on the two-dimensional X-ray image I1 according to the shape and angle range of the trajectory of the X-ray tube 12.

Here, the angular range of the trajectory of the X-ray tube 12 will be described with reference to FIG. 9. FIG. 9 is a diagram showing an example of the angular range of the trajectory according to the third embodiment. The trajectory T31 shown in FIG. 9 is a linear trajectory along the X-axis direction. When moving the X-ray tube 12 along the trajectory T31, the control function 201 first rotates and moves the C-arm 15 to place the X-ray tube 12 at position X4 shown in FIG. 9 and to make the X-ray tube 12 and the X-ray detector 16 face each other across the subject P. Next, the control function 201 rotates the C-arm 15 by an angular range θ1 around an axis that passes through position X5 and is parallel to the Z-axis direction as the rotation axis. As a result, the X-ray tube 12 moves along the trajectory T31 to position X6 shown in FIG. 9.

That is, the angular range θ1 is a parameter that indicates the size of the trajectory T31. In tomosynthesis imaging, the larger the angular range θ1, the greater the change in the X-ray irradiation angle of the multiple projection data collected. In turn, the larger the angular range θ1, the greater the reduction in artifacts in the multiple tomographic images reconstructed from the multiple projection data. On the other hand, the larger the angular range θ1, the longer the collection time required to collect the multiple projection data.

In addition, in tomosynthesis imaging, the angular range of the trajectory of the X-ray tube 12 is narrower than 180 degrees. In other words, the trajectory of the X-ray tube 12 in tomosynthesis imaging is an trajectory with an angular range narrower than 180 degrees. According to tomosynthesis imaging, it is possible to collect tomographic images with a lower dose than imaging methods (such as CT scans) that irradiate X-rays from an angular range wider than 180 degrees.

Below, a case where image processing is performed according to the shape and angle range of the trajectory of the X-ray tube 12 will be described with reference to Figs. 10A and 10B. Note that Figs. 10A and 10B are diagrams showing an example of a processed image according to the third embodiment.

The trajectory T32 shown in FIG. 10A is a linear trajectory along the X-axis direction, and has an angular range of "40 degrees." The image processing function 203 generates a processed image I26 by performing image processing according to the trajectory T32 on the two-dimensional X-ray image I1. The trajectory T33 shown in FIG. 10B is a linear trajectory along the X-axis direction, and has an angular range of "20 degrees." The image processing function 203 generates a processed image I27 by performing image processing according to the trajectory T33 on the two-dimensional X-ray image I1.

Here, as shown in Figures 10A and 10B, the artifacts predicted in processed image I26 corresponding to trajectory T32 with an angle range of "40 degrees" are fewer than the artifacts predicted in processed image I27 corresponding to trajectory T33 with an angle range of "20 degrees". In addition, the acquisition time corresponding to processed image I26 is "8 seconds", and the acquisition time corresponding to processed image I27 is "4 seconds". In other words, the acquisition time when performing tomosynthesis imaging with trajectory T32 with an angle range of "40 degrees" is longer than the acquisition time when performing tomosynthesis imaging with trajectory T33 with an angle range of "20 degrees".

For example, the display control function 204 displays the processed image and the acquisition time shown in FIG. 10A and FIG. 10B on the display 18. Then, the operator can select the trajectory of the X-ray tube 12 by selecting either the processed image I26 or the processed image I27 based on the processed image and the acquisition time. For example, when prioritizing reduction of artifacts, the operator selects the processed image I26. In this case, the control function 201 sets the trajectory T32 as the imaging condition. Also, for example, when prioritizing shortening the acquisition time, the operator selects the processed image I27. In this case, the control function 201 sets the trajectory T33 as the imaging condition. Note that the display control function 204 may display the trajectory and angle range corresponding to the processed image in addition to the processed image and the acquisition time, as shown in FIG. 10A and FIG. 10B.

In the above-described embodiment, the image processing is performed according to the trajectory of the X-ray tube 12. However, the embodiment is not limited to this. For example, the image processing function 203 may perform image processing on the two-dimensional X-ray image I1 according to the trajectory of the X-ray tube 12 and various imaging conditions other than the trajectory.

For example, the image processing function 203 performs image processing on the two-dimensional X-ray image I1 according to the trajectory of the X-ray tube 12 and the X-ray dose. For example, the image processing function 203 first performs image processing on the two-dimensional X-ray image I1 according to the trajectory T11 to generate the processed image I21 shown in FIG. 5A. Next, the image processing function 203 performs image processing on the processed image I21 according to the X-ray dose D1 to generate a processed image I28 (not shown). The image processing function 203 also performs image processing on the processed image I21 according to the X-ray dose D2, which is higher than the X-ray dose D1, to generate a processed image I29 (not shown).

As an example, the image processing function 203 generates a processed image I28 by adding a noise component corresponding to the X-ray dose D1 to the processed image I21. The image processing function 203 also generates a processed image I29 by adding a noise component corresponding to the X-ray dose D2, which is less than the noise component corresponding to the X-ray dose D1, to the processed image I21. That is, the image processing function 203 generates the processed image I28 and the processed image I29 so that the noise of the processed image I29 is less than that of the processed image I28. Next, the display control function 204 displays the processed image I28 and the processed image I29 on the display 18. Then, the operator selects the X-ray dose by selecting either the processed image I28 or the processed image I29.

For example, if the noise shown in processed image I28 is within the acceptable range, the operator selects processed image I28. In this case, the control function 201 sets the X-ray dose D1 as the imaging condition. This allows the X-ray diagnostic apparatus 1 to reduce the radiation dose to which the subject P is exposed during tomosynthesis imaging. On the other hand, if it is determined that the noise shown in processed image I28 interferes with the observation of the area to be examined, the operator selects processed image I29. In this case, the control function 201 sets the X-ray dose D2 as the imaging condition.

As another example, the image processing function 203 performs image processing on the two-dimensional X-ray image I1 according to the trajectory of the X-ray tube 12 and the frame rate. Note that the frame rate may be the number of projection data collected per unit time in tomosynthesis imaging, or the number of projection data collected per unit angle range.

For example, the image processing function 203 first performs image processing according to the trajectory T11 on the two-dimensional X-ray image I1 to generate the processed image I21 shown in FIG. 5A. Next, the image processing function 203 performs image processing according to the frame rate F1 on the processed image I21 to generate a processed image I30 (not shown). Also, the image processing function 203 performs image processing according to a frame rate F2 higher than the frame rate F1 on the processed image I21 to generate a processed image I31 (not shown). As an example, the image processing function 203 generates the processed image I30 and the processed image I31 by increasing or decreasing the artifacts predicted in the processed image I21 so that the artifacts predicted in the processed image I31 are less than the artifacts predicted in the processed image I30. Next, the display control function 204 displays the processed image I30 and the processed image I31 on the display 18. Then, the operator selects the frame rate by selecting either Processed Image I30 or Processed Image I31.

For example, when the operator refers to the predicted artifacts in the processed image I30 and determines that the artifacts will not interfere with the observation of the area to be examined, he or she selects the processed image I30. In this case, the control function 201 sets the frame rate F1 as the imaging condition. This allows the X-ray diagnostic apparatus 1 to reduce the radiation dose to which the subject P is exposed during tomosynthesis imaging. On the other hand, when the operator refers to the predicted artifacts in the processed image I30 and determines that the artifacts will interfere with the observation of the area to be examined, he or she selects the processed image I31. In this case, the control function 201 sets the frame rate F2 as the imaging condition.

As another example, the image processing function 203 performs image processing on the two-dimensional X-ray image I1 according to the trajectory of the X-ray tube 12 and the reconstruction conditions. For example, the image processing function 203 first performs image processing on the two-dimensional X-ray image I1 according to the trajectory T11 to generate the processed image I21 shown in FIG. 5A.

Here, the processed image I21 corresponds to the reconstruction condition "DC component present". In other words, the processed image I21 is a prediction of artifacts in a tomographic image when back projection processing is performed by the FBP method without removing the DC component of the projection data. Next, the image processing function 203 performs image processing to remove the DC component from the processed image I21, thereby generating a processed image I32 (not shown). Here, the processed image I32 corresponds to the reconstruction condition "DC component absent". In other words, the processed image I32 is a prediction of artifacts in a tomographic image when back projection processing is performed by the FBP method after removing the DC component from the projection data.

Next, the display control function 204 displays the processed image I21 and the processed image I32 on the display 18. Then, the operator can select the reconstruction condition by selecting either the processed image I21 or the processed image I32. For example, if the operator selects the processed image I21, the control function 201 sets "DC component present" as the reconstruction condition. This allows the X-ray diagnostic device 1 to reconstruct a tomographic image containing a DC component. Such a tomographic image has a natural appearance because it contains a DC component like a fluoroscopic image, and is often easy for the operator to observe. Also, for example, if the operator selects the processed image I32, the control function 201 sets "no DC component" as the reconstruction condition. This allows the X-ray diagnostic device 1 to perform back projection processing after removing the DC component, and improve the resolution in the Y-axis direction of the tomographic image.

In the above-described embodiment, a case has been described in which image processing is performed on the two-dimensional X-ray image I1 based on the image processing settings stored in the memory 17. However, the embodiment is not limited to this. For example, the memory 17 stores a trained model that is functionalized to perform image processing based on the trajectory of the X-ray tube 12. In this case, the image processing function 203 generates a processed image by having the trained model perform image processing on the two-dimensional X-ray image I1 based on the trajectory of the X-ray tube 12.

For example, the image processing function 203 generates a trained model using the results of previously performed tomosynthesis imaging as training data. As one example, the image processing function 203 acquires, as training data, fluoroscopic images collected for positioning in previously performed tomosynthesis imaging, the trajectory of the X-ray tube 12 in that tomosynthesis imaging, and tomographic images collected by that tomosynthesis imaging. Then, the image processing function 203 executes machine learning by inputting these training data into a machine learning engine.

Specifically, the image processing function 203 inputs the fluoroscopic image and the trajectory of the X-ray tube 12 as input data and the collected tomographic image as output data to the machine learning engine. As a result, the machine learning engine determines image processing parameters so that the fluoroscopic image after image processing approximates the tomographic image, and generates a trained model. For example, the machine learning engine determines the image processing parameters using various algorithms such as deep learning, neural network, logistic regression analysis, nonlinear discriminant analysis, support vector machine (SVM), random forest, and naive Bayes.

Then, when setting the imaging conditions for tomosynthesis imaging of the subject P, the image processing function 203 inputs the two-dimensional X-ray image I1 to the trained model. As a result, the trained model performs image processing on the two-dimensional X-ray image I1 based on the determined parameters. In other words, the image processing function 203 causes the trained model to perform image processing on the two-dimensional X-ray image I1 to generate a processed image.

In the above-described embodiment, a case has been described in which, in addition to a processed image, a trajectory corresponding to the processed image, the collection time required to collect multiple projection data based on the trajectory corresponding to the processed image, the angle range of the trajectory corresponding to the processed image, etc. are displayed. However, examples of information displayed in addition to the processed image are not limited to this.

As an example, as shown in FIG. 11, the display control function 204 displays, in addition to the processed image I33, a trajectory T34 corresponding to the processed image I33, the acquisition time "8 seconds" required to acquire multiple projection data based on the trajectory T34, and the angular range of the trajectory T34 "20 degrees". Furthermore, the display control function 204 displays an area (interference area) where the imaging system of the X-ray diagnostic device 1 interferes when the X-ray tube 12 moves according to the trajectory T34. Here, the imaging system includes, for example, the X-ray tube 12, the X-ray aperture 13, the C-arm 15, the X-ray detector 16, etc. FIG. 11 is a diagram showing the interference area according to the third embodiment.

In other words, in tomosynthesis imaging, other components in the imaging system also move in conjunction with the movement of the X-ray tube 12, so the operator must move away from the area where the imaging system interferes. In other words, in tomosynthesis imaging, the operator cannot use the area where the imaging system interferes as a workspace. Therefore, by referring to the interference area in addition to the processed image I33, the operator can determine whether or not trajectory T34 is appropriate from the perspective of securing a workspace.

In the above-described embodiment, the X-ray tube 12 is described as being movable in multiple directions. However, the embodiment is not limited to this, and the X-ray tube 12 may be movable in only one direction. In this case, the image processing function 203 can generate multiple processed images by performing multiple image processing on the two-dimensional X-ray image I1 according to the angular range of the trajectory of the X-ray tube 12.

In the above-described embodiment, the X-ray diagnostic apparatus 1 is described as having a C-arm 15, and the X-ray tube 12 moves due to the rotation of the C-arm 15. However, the embodiment is not limited to this. That is, the mechanism for moving the X-ray tube 12 is not limited to the C-arm 15. In other words, the above-described embodiment is applicable to any X-ray diagnostic apparatus capable of performing tomosynthesis imaging. As an example, the above-described embodiment is applicable to a mammography apparatus capable of performing tomosynthesis imaging.

2B, 2C, and 9, the trajectory of the X-ray tube 12 as viewed from the Z-axis direction has been described as being an arc-shaped curve including changes in the Y-axis direction. However, the embodiment is not limited to this. For example, the trajectory of the X-ray tube 12 as viewed from the Z-axis direction may be a trajectory of another shape including changes in the Y-axis direction. For example, the trajectory of the X-ray tube 12 as viewed from the Z-axis direction may be another curved shape such as a quadratic curve or a catenary curve, or a broken line shape. Alternatively, the trajectory of the X-ray tube 12 as viewed from the Z-axis direction may be a linear trajectory that does not include changes in the Y-axis direction. In other words, the trajectory of the X-ray tube 12 as viewed from the Z-axis direction may be any shape that can perform tomosynthesis imaging. Also, in FIGS. 2B, 2C, and 9, the X-ray tube 12 has been described as being located above the X-ray detector 16, but the X-ray tube 12 may be located below the X-ray detector 16.

2B and 2C, the X-ray detector 16 has been described as moving in a state facing the X-ray tube 12. That is, the trajectory of the X-ray detector 16 as viewed from the Z-axis direction has been described as a curve including changes in the Y-axis direction. However, the embodiment is not limited to this. For example, the trajectory of the X-ray detector 16 as viewed from the Z-axis direction may be an trajectory of another shape including changes in the Y-axis direction, or may be a linear trajectory not including changes in the Y-axis direction. As an example, when the X-ray tube 12 moves linearly in the +X direction as viewed from the Z-axis direction, the X-ray detector 16 may move linearly in the -X direction. Alternatively, the X-ray detector 16 may not move. For example, the size and position of the X-ray detector 16 are adjusted so that the X-rays transmitted through the subject P can be detected while the X-ray tube 12 irradiates X-rays from multiple positions.

In the above-described embodiment, the case where the results of the prediction processing by the image processing function 203 are displayed has been described. For example, in Figs. 5A to 5D, the case where processed images I21 to I24 are generated and displayed on the display 18 has been described. However, the embodiment is not limited to this. For example, the processing circuitry 20 may further include a specification function 205 as shown in Fig. 12, and the display control function 204 may display the recommended trajectory specified by the specification function 205. Fig. 12 is a block diagram showing an example of the configuration of an X-ray diagnostic apparatus 1 according to the third embodiment.

The identification function 205 identifies a recommended trajectory based on the results of prediction processing by the image processing function 203. For example, the identification function 205 identifies a recommended trajectory based on the processed images I21 to I24 shown in Figures 5A to 5D. Specifically, when the operator focuses on position C1, no artifacts occur at position C1 in the processed image I22 in Figure 5B and the processed image I24 in Figure 5D, so the identification function 205 can identify trajectories T12 and T14 as recommended trajectories.

The display control function 204 displays the recommended trajectory identified by the identification function 205 on the display 18. As an example, the display control function 204 displays only the processed image I22 and the processed image I24 of the processed images I21 to I24, together with the trajectories T12 and T14. Alternatively, the display control function 204 may display the processed images I21 to I24 together with the trajectories T11 to T14, and may further display information indicating that the trajectories T12 and T14 of the trajectories T11 to T14 are the recommended trajectories. Alternatively, the display control function 204 may omit displaying the processed images I21 to I24, and display the trajectories T12 and T14 as the recommended trajectories.

The identification function 205 may also identify a single recommended trajectory based on the results of prediction processing by the image processing function 203. For example, when the operator focuses on position C1, no artifacts occur at position C1 in the processed image I22 of FIG. 5B and the processed image I24 of FIG. 5D, and furthermore, the collection time of the processed image I22 is shorter, so the identification function 205 identifies trajectory T12 as the recommended trajectory. Then, the display control function 204 causes the display 18 to display the recommended trajectory identified by the identification function 205.

Alternatively, the display of the recommended trajectory by the display control function 204 may be omitted. For example, the identification function 205 identifies a single recommended trajectory based on the result of the prediction processing by the image processing function 203. Then, the control function 201 sets the recommended trajectory as the shooting condition and performs tomosynthesis shooting. In other words, the control function 201 may automatically set the trajectory for tomosynthesis shooting based on the result of the prediction processing by the image processing function 203.

In the above-described embodiment, a case has been described in which a recommended trajectory is identified based on the results of prediction processing by the image processing function 203. However, the embodiment is not limited to this. That is, the X-ray diagnostic device 1 can omit the prediction processing by the image processing function 203 and identify a recommended trajectory based on a two-dimensional X-ray image.

Identification of a recommended trajectory based on a two-dimensional X-ray image can be achieved, for example, by a machine learning technique. For example, the memory 17 stores a trained model that is functionalized to receive an input of a two-dimensional X-ray image and output a recommended trajectory. Such a trained model may be generated by the identification function 205 or an external device other than the X-ray diagnostic device 1.

As an example, the identification function 205 acquires, as learning data, a large number of pairs of two-dimensional X-ray images and correct trajectories used in tomosynthesis imaging performed after the collection of the two-dimensional X-ray images. The identification function 205 also inputs the two-dimensional X-ray images as input data and the correct trajectory as output data to the machine learning engine. In this way, the identification function 205 can train the machine learning engine to eliminate inconsistencies between the recommended trajectory estimated based on the two-dimensional X-ray images and the correct trajectory, thereby generating a trained model. For example, the machine learning engine can be configured using a neural network or the like.

Then, when setting the imaging conditions for tomosynthesis imaging of the subject P, the identification function 205 inputs the two-dimensional X-ray image I1 into the learned model. As a result, the identification function 205 identifies a recommended trajectory that is recommended as the trajectory along which the X-ray tube 12 moves in tomosynthesis imaging of the subject P. Furthermore, the display control function 204 causes the display 18 to display the recommended trajectory identified by the identification function 205. Alternatively, the control function 201 may automatically set the trajectory for tomosynthesis imaging based on the recommended trajectory identified by the identification function 205.

In addition, in the above-described embodiment, the processing circuit 20 has the reception function 202, the image processing function 203, the display control function 204, and the specific function 205, but the embodiment is not limited to this. For example, a processing circuit provided in an apparatus other than the X-ray diagnostic apparatus 1 may have functions equivalent to the reception function 202, the image processing function 203, the display control function 204, and the specific function 205.

As an example, as shown in FIG. 13, the X-ray diagnostic apparatus 1 is connected to a medical image processing apparatus 3 via a network NW. The medical image processing apparatus 3 also includes an input interface 31, a display 32, a memory 33, and a processing circuit 34. FIG. 13 is a block diagram showing an example of the configuration of the medical image processing apparatus 3 according to the third embodiment.

The input interface 31 accepts various input operations from the operator, converts the accepted input operations into electrical signals, and outputs the electrical signals to the processing circuitry 34. For example, the input interface 31 is realized by a mouse, a keyboard, a trackball, a switch, a button, a joystick, a touchpad that performs input operations by touching the operation surface, a touch screen that integrates a display screen and a touchpad, a non-contact input circuit using an optical sensor, a voice input circuit, and the like. The input interface 31 may be configured as a tablet terminal or the like that can wirelessly communicate with the processing circuitry 34. The input interface 31 is not limited to only those that have physical operating parts such as a mouse and a keyboard. For example, an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the medical image processing device 3 and outputs the electrical signal to the processing circuitry 34 is also included as an example of the input interface 31.

The memory 33 is realized, for example, by a semiconductor memory element such as a RAM or a flash memory, a hard disk, an optical disk, etc. For example, the memory 33 stores programs corresponding to various functions executed by circuits included in the medical image processing device 3. Note that the memory 33 may also be realized by a group of servers (cloud) connected to the medical image processing device 3 via a network NW.

The display 32 displays various types of information. For example, under the control of the processing circuitry 34, the display 32 displays a GUI for receiving instructions from an operator and various X-ray images. For example, the display 32 is a liquid crystal display or a CRT display. The display 32 may be a desktop type, or may be configured as a tablet terminal or the like capable of wireless communication with the processing circuitry 34.

The processing circuitry 34 controls the operation of the entire medical image processing device 3 by executing the image processing function 341, the output function 342, the reception function 343, and the identification function 344. For example, the image processing function 341 first acquires a two-dimensional X-ray image I1 from the X-ray diagnostic device 1 via the network NW. The image processing function 341 also specifies at least one trajectory of the X-ray tube 12 in tomosynthesis imaging. Next, the image processing function 341 performs image processing on the two-dimensional X-ray image I1 according to the trajectory of the X-ray tube 12, thereby generating a processed image.

For example, the image processing function 341 generates multiple processed images by performing multiple image processes on the two-dimensional X-ray image I1 according to multiple trajectories. Next, the output function 342 displays the generated multiple processed images on the display 32. Next, the reception function 343 receives an operation from the operator to select one of the multiple processed images, and identifies the trajectory corresponding to the selected processed image. Next, the output function 342 outputs the trajectory of the X-ray tube 12 identified by the reception function 343 to the X-ray diagnostic device 1. Then, the X-ray diagnostic device 1 sets the trajectory of the X-ray tube 12 received from the medical image processing device 3 as an imaging condition.

Alternatively, the output function 342 outputs the multiple processed images generated by the image processing function 341 to the X-ray diagnostic apparatus 1. In this case, the display control function 204 in the X-ray diagnostic apparatus 1 causes the multiple processed images received from the medical image processing device 3 to be displayed on the display 18. Next, the reception function 202 receives an operation from the operator to select one of the multiple processed images. Then, the control function 201 sets the trajectory corresponding to the selected processed image as the shooting condition.

As another example, first, the reception function 343 receives an input operation of the trajectory of the X-ray tube 12 from the operator. Next, the image processing function 341 generates a processed image by executing image processing on the two-dimensional X-ray image I1 according to the trajectory received by the reception function 343. Next, the output function 342 displays the generated processed image on the display 32. Here, if the operator determines that the trajectory is appropriate, the output function 342 outputs the trajectory received by the reception function 343 to the X-ray diagnostic device 1. Then, the X-ray diagnostic device 1 sets the trajectory of the X-ray tube 12 received from the medical image processing device 3 as the imaging condition.

Alternatively, the identification function 344 identifies a recommended trajectory based on the processed image generated by the image processing function 341. Alternatively, the generation process of the processed image by the image processing function 341 is omitted, and the identification function 344 identifies a recommended trajectory based on the two-dimensional X-ray image I1. Then, the output function 342 displays the recommended trajectory on the display 32. Alternatively, the output function 342 outputs the recommended trajectory to the X-ray diagnostic device 1. In this case, the X-ray diagnostic device 1 can display the recommended trajectory on the display 18, or automatically set the recommended trajectory as an imaging condition.

In the above-described embodiment, tomosynthesis imaging has been described as the second imaging. However, the embodiment is not limited to this, and can be similarly applied to various X-ray imaging methods that collect multiple projection data with different X-ray irradiation angles.

For example, there is known an X-ray imaging method in which two projection data from different directions are collected from a subject P, and a reconstructed image is obtained from these two projection data. When such an X-ray imaging method is executed as the second imaging, the above-mentioned embodiments can be similarly applied. That is, when collecting two projection data, X-rays are irradiated from two different positions, and the line segment connecting these two positions can be treated as the trajectory of the X-ray tube 12. Then, the X-ray diagnostic device 1 or the medical image processing device 3 can perform a prediction process to predict artifacts that will occur when the two projection data are collected on this trajectory. Alternatively, the X-ray diagnostic device 1 or the medical image processing device 3 can also identify a recommended trajectory for collecting the two projection data.

The components of each device according to the first to third embodiments are conceptual and functional, and do not necessarily have to be physically configured as shown in the figures. In other words, the specific form of distribution and integration of each device is not limited to that shown in the figures, and all or part of the devices can be functionally or physically distributed and integrated in any unit depending on various loads and usage conditions. Furthermore, all or any part of the processing functions performed by each device can be realized by a CPU and a program analyzed and executed by the CPU, or can be realized as hardware using wired logic.

The image processing methods described in the first to third embodiments can be realized by executing a prepared control program on a computer such as a personal computer or a workstation. This image processing program can be distributed via a network such as the Internet. This image processing program can also be recorded on a computer-readable recording medium such as a hard disk, flexible disk (FD), CD-ROM, MO, or DVD, and executed by being read from the recording medium by a computer.

At least one of the embodiments described above can facilitate the selection of a trajectory for X-ray imaging.

Although several embodiments of the present invention 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, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are within the scope of the invention and its equivalents as set forth in the claims, as well as the scope and gist of the invention.

REFERENCE SIGNS LIST 1 X-ray diagnostic apparatus 12 X-ray tube 15 C-arm 17 Memory 18 Display 19 Input interface 20 Processing circuit 201 Control function 202 Reception function 203 Image processing function 204 Display control function 205 Specific function 3 Medical image processing apparatus 31 Input interface 32 Display 33 Memory 34 Processing circuit 341 Image processing function 342 Output function 343 Reception function 344 Specific function

Claims (22)

an image acquisition unit that acquires a two-dimensional X-ray image of the subject captured in the first imaging;
a trajectory designation unit that designates at least one trajectory along which the X-ray generation unit moves in a second imaging operation that is performed after the first imaging operation;
and an image processing unit that performs a prediction process to predict, based on the two-dimensional X-ray image and the trajectory, an artifact that will occur when the second imaging is performed on the trajectory, the artifact extending from a part of the subject having a relatively high X-ray absorption rate in a direction corresponding to the trajectory . The X-ray diagnostic device according to claim 1, further comprising a display control unit that displays the results of the prediction process. the image processing unit generates a processed image by performing image processing on the two-dimensional X-ray image according to the trajectory;
The X-ray diagnostic apparatus according to claim 2 , wherein the display control unit causes the processed image to be displayed as a result of the prediction process. the image processing unit generates a plurality of the processed images by executing a plurality of the image processing operations corresponding to the plurality of the trajectories on the two-dimensional X-ray image;
The X-ray diagnostic apparatus according to claim 3 , wherein the display control unit causes a plurality of the processed images to be displayed as a result of the prediction process. A reception unit that receives an input operation of the trajectory is further provided,
The X-ray diagnostic apparatus according to claim 3 , wherein the trajectory designation unit designates the trajectory based on the input operation. A storage unit is further provided to store image processing settings corresponding to each of the plurality of trajectories,
5. The X-ray diagnostic apparatus according to claim 4, wherein the image processing unit reads out image processing settings from the storage unit in accordance with the trajectory, and performs image processing based on the read image processing settings on the two-dimensional X-ray image to generate the processed image. The X-ray diagnostic device according to claim 6, wherein the image processing unit reads out and synthesizes a plurality of image processing settings from the storage unit according to the trajectory, and performs image processing based on the synthesized plurality of image processing settings on the two-dimensional X-ray image to generate the processed image. Further comprising a storage unit configured to store a trained model that is functionalized to perform image processing based on the trajectory,
The X-ray diagnostic apparatus according to any one of claims 3 to 5, wherein the image processing unit generates the processed image by having the trained model perform image processing on the two-dimensional X-ray image based on the trajectory. The X-ray diagnostic device according to any one of claims 3 to 8, wherein the image processing unit generates the processed image by performing image processing on the two-dimensional X-ray image according to the shape and angle range of the trajectory. The X-ray diagnostic device according to any one of claims 3 to 9, wherein the image processing unit generates the processed image by performing image processing on the two-dimensional X-ray image according to the trajectory and the X-ray dose. The X-ray diagnostic device according to any one of claims 3 to 10, wherein the image processing unit generates the processed image by performing image processing on the two-dimensional X-ray image according to the trajectory and frame rate. an image acquisition unit that acquires a two-dimensional X-ray image of the subject captured in the first imaging;
a trajectory designation unit that designates at least one trajectory along which the X-ray generation unit moves in a second imaging operation that is performed after the first imaging operation;
an image processing unit that performs a prediction process to predict an artifact that will occur when the second imaging is performed on the trajectory, based on the two-dimensional X-ray image and the trajectory;
a display control unit that displays a result of the prediction process,
the image processing unit performs image processing on the two-dimensional X-ray image in accordance with the trajectory and the frame rate to generate a processed image;
The display control unit displays the processed image as a result of the prediction processing. The X-ray diagnostic apparatus according to any one of claims 3 to 12 , wherein the image processing unit generates the processed image by executing image processing on the two-dimensional X-ray image according to the trajectory and reconstruction conditions. The X-ray diagnostic apparatus according to any one of claims 3 to 13 , wherein the display control unit further causes the trajectory corresponding to the processed image to be displayed. The X-ray diagnostic apparatus according to any one of claims 3 to 14 , wherein the display control unit further displays a region in which an imaging system interferes when the X-ray generation unit moves along the trajectory corresponding to the processed image. an image acquisition unit that acquires a two-dimensional X-ray image of the subject captured in the first imaging;
a trajectory designation unit that designates at least one trajectory along which the X-ray generation unit moves in a second imaging operation that is performed after the first imaging operation;
an image processing unit that performs a prediction process to predict an artifact that will occur when the second imaging is performed on the trajectory, based on the two-dimensional X-ray image and the trajectory;
a display control unit that displays a result of the prediction process,
the image processing unit generates a processed image by performing image processing on the two-dimensional X-ray image according to the trajectory;
the display control unit displays the processed image as a result of the prediction processing, and further displays a region in which an imaging system interferes when the X-ray generation unit moves along the trajectory corresponding to the processed image. 17. The X-ray diagnostic apparatus according to claim 3 , wherein the display control unit further causes an acquisition time required to acquire a plurality of projection data based on the trajectory corresponding to the processed image to be displayed. an image acquisition unit that acquires a two-dimensional X-ray image of the subject captured in the first imaging;
a trajectory designation unit that designates at least one trajectory along which the X-ray generation unit moves in a second imaging operation that is performed after the first imaging operation;
an image processing unit that performs a prediction process for predicting an artifact that will occur when the second imaging is performed on the trajectory, based on the two-dimensional X-ray image and the trajectory;
a display control unit that displays a result of the prediction process,
the image processing unit generates a processed image by performing image processing on the two-dimensional X-ray image according to the trajectory;
The display control unit displays the processed image as a result of the prediction processing, and further displays an acquisition time required to acquire a plurality of projection data based on the trajectory corresponding to the processed image. The X-ray diagnostic apparatus according to any one of claims 3 to 18 , wherein the image processing unit generates the processed image by performing image processing on the two-dimensional X-ray image according to the trajectory in an angular range narrower than 180 degrees. The X-ray diagnostic device according to claim 1, further comprising a determination unit that determines a recommended trajectory based on the results of the prediction process. The X-ray diagnostic apparatus according to claim 20 , further comprising a display control unit that displays the recommended trajectory. 22. The X-ray diagnostic apparatus according to claim 1 , wherein the two-dimensional X-ray image is an image of the subject captured in the first imaging performed for positioning.

Images