JP2018164739A - X-ray diagnostic device, image processing device, and image processing program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily provide a stereoscopic image of parametric imaging. An X-ray diagnostic apparatus according to an embodiment generates a plurality of time-series first blood vessel images having a first observation direction as an observation direction, and at least one second image having a second observation direction as an observation direction. Generate a blood vessel image. The device deforms a plurality of first blood vessel images based on the blood vessel shape in the first blood vessel image and the blood vessel shape in the second blood vessel image data, so that the second observation direction is the observation direction and the plurality of second blood vessels. Generates a plurality of third blood vessel images corresponding to each time phase of one blood vessel image. The apparatus uses a plurality of first blood vessel images to generate a first color image reflecting the flow of a contrast medium with the first observation direction as the observation direction, and uses the plurality of third blood vessel images to generate a first color image. 2 Generates a second color image reflecting the flow of the contrast medium with the observation direction as the observation direction. The device causes the display unit to display a stereoscopic image based on the first color image and the second color image. [Selection diagram] Fig. 1

Description

  Embodiments described herein relate generally to an X-ray diagnostic apparatus, an image processing apparatus, and an image processing program.

  Conventionally, DSA (Digital Subtraction Angiography) is known as one of blood vessel imaging methods in an X-ray diagnostic apparatus. DSA is a technique for obtaining image data in which blood vessels stained with a contrast agent are selectively depicted by performing a difference between X-ray image data before and after the injection of the contrast agent into a subject. For example, in DSA, X-ray image data in the absence of a contrast agent is collected as mask image data by imaging before injecting the contrast agent. Then, X-ray image data in the presence of the contrast agent is collected as contrast image data by imaging while injecting the contrast agent. Then, DSA image data is generated by a difference process between the mask image data and the contrast image data.

  There is also a technique called parametric imaging that uses the DSA to image a parameter related to the inflow time of a contrast agent. In parametric imaging, for example, a change in pixel value at each position of DSA image data is regarded as a change in contrast agent concentration, and a time at which a time-series change in pixel value reaches a peak or a specific value is calculated as an inflow time. In parametric imaging, parametric imaging image data (also referred to as “parametric image data”) is generated by mapping a color corresponding to the calculated inflow time to each position.

  Various techniques for providing stereoscopic X-ray image data have been proposed for X-ray diagnostic apparatuses. For example, a technique for capturing parallax images for the right eye and the left eye by changing the angle of the C-arm is known.

Japanese Patent Laid-Open No. 2014-200339

  The problem to be solved by the present invention is to provide an X-ray diagnostic apparatus, an image processing apparatus, and an image processing program that can easily provide a stereoscopic image of parametric imaging.

  The X-ray diagnostic apparatus according to the embodiment includes a blood vessel image generation unit, an image processing unit, a color image generation unit, and a display control unit. The blood vessel image generation unit generates a plurality of time-series first blood vessel image data with the first observation direction as the observation direction, and generates at least one second blood vessel image data with the second observation direction as the observation direction. To do. The image processing unit includes the plurality of first blood vessels based on a blood vessel shape in at least one of the plurality of first blood vessel image data and a blood vessel shape in at least one of the at least one second blood vessel image data. By deforming a plurality of blood vessel image data, the second observation direction is set as the observation direction, and a plurality of third blood vessel image data corresponding to each time phase of the plurality of first blood vessel image data is generated. To do. The color image generation unit uses at least a plurality of the plurality of first blood vessel image data to generate first color image data that reflects the flow of the contrast agent, with the first observation direction as the observation direction. Second color image data reflecting the flow of the contrast agent is generated, with the second observation direction as the observation direction, using at least a plurality of the plurality of third blood vessel image data. The display control unit causes the display unit to display a stereoscopic image based on the first color image data and the second color image data.

FIG. 1 is a diagram illustrating an example of the configuration of the X-ray diagnostic apparatus according to the first embodiment. FIG. 2A is a diagram for explaining the rotation direction of the C-arm according to the first embodiment. FIG. 2B is a diagram for explaining the rotation direction of the C-arm according to the first embodiment. FIG. 3 is a flowchart showing a processing procedure of the X-ray diagnostic apparatus according to the first embodiment. FIG. 4 is a flowchart showing a processing procedure of DSA image generation processing according to the first embodiment. FIG. 5A is a diagram for explaining the DSA image generation processing according to the first embodiment. FIG. 5B is a diagram for explaining the DSA image generation processing according to the first embodiment. FIG. 6 is a flowchart illustrating a processing procedure of the warping process according to the first embodiment. FIG. 7A is a diagram for explaining the warping process according to the first embodiment. FIG. 7B is a diagram for explaining the warping process according to the first embodiment. FIG. 8 is a flowchart showing a processing procedure of DSA image generation processing according to the second embodiment. FIG. 9 is a diagram for explaining the DSA image generation processing according to the second embodiment. FIG. 10 is a flowchart illustrating a processing procedure of the warping process according to the second embodiment. FIG. 11A is a diagram for explaining a warping process according to the second embodiment. FIG. 11B is a diagram for explaining a warping process according to the second embodiment. FIG. 11C is a diagram for explaining a warping process according to the second embodiment. FIG. 12 is a diagram for explaining processing of the X-ray diagnostic apparatus according to the modification of the second embodiment. FIG. 13A is a diagram for explaining processing of the X-ray diagnostic apparatus according to the third embodiment. FIG. 13B is a diagram for explaining processing of the X-ray diagnostic apparatus according to the third embodiment. FIG. 13C is a diagram for explaining processing of the X-ray diagnostic apparatus according to the third embodiment. FIG. 13D is a diagram for explaining processing of the X-ray diagnostic apparatus according to the third embodiment. FIG. 14 is a diagram for explaining processing of the X-ray diagnostic apparatus according to the modification of the third embodiment.

  Hereinafter, an X-ray diagnostic apparatus, an image processing apparatus, and an image processing program according to embodiments will be described with reference to the drawings. Note that the embodiments are not limited to the following embodiments. In addition, the contents described in one embodiment can be applied to other embodiments in principle as well.

(First embodiment)
FIG. 1 is a diagram illustrating 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 according to the first embodiment includes an X-ray imaging mechanism 10 and an image processing apparatus 100.

  The X-ray imaging mechanism 10 includes an X-ray tube 11, a detector (Flat Panel Detector: FPD) 12, a C-type arm 13, and a bed 14, and an injector 60 is connected thereto.

  The injector 60 is a device for injecting a contrast medium from a catheter inserted into the subject P. Here, the start of contrast medium injection from the injector 60 may be performed in accordance with an injection start instruction received via the image processing apparatus 100 described later, or an operator such as an operator directly connects to the injector 60. Alternatively, it may be executed in accordance with the injection start instruction input to the terminal. Alternatively, the contrast agent may be manually injected by a doctor using a syringe.

  The C-type arm 13 supports an X-ray tube 11 and a detector 12 that detects X-rays emitted from the X-ray tube 11. The C-type arm 13 rotates at high speed like a propeller around a subject P lying on the bed 14 by a motor (not shown). Here, the C-shaped arm 13 is rotatably supported with respect to XYZ axes that are three orthogonal axes, and is individually rotated on each axis by a driving unit (not shown). The C-shaped arm 13 is an example of a support machine.

  2A and 2B are diagrams for explaining the rotation direction of the C-arm 13 according to the first embodiment. FIG. 2A illustrates a view of the subject P viewed from the positive direction of the Z axis, and FIG. 2B illustrates a view of the subject P viewed from the positive direction of the X axis.

  As shown in FIG. 2A, the left rotation of the subject P around the Z from the Y axis is called LAO (Left Anterior Oblique), and the rotation opposite to LAO is called RAO (Right Anterior Oblique). As shown in FIG. 2B, the rotation from the XY plane to the Z axis is called CRA (CRANIAL), and the opposite rotation of CRA is called CAU (CAUDAL). For example, when the X-ray detector 12 is positioned in the positive direction (that is, in front of the patient), the angle of the C-arm 13 is expressed as (RAO / LAO 0, CRA / CAU 0). This indicates that the RAO / LAO angle is 0 degree and the CRA / CAU angle is 0 degree.

  The X-ray tube 11 is an X-ray source that generates X-rays using a high voltage supplied from a high voltage generator (not shown). The detector 12 is an apparatus in which a plurality of X-ray detection elements for detecting X-rays transmitted through the subject P are arranged in a matrix. Each X-ray detection element included in the detector 12 outputs X-rays transmitted through the subject P to an A / D converter 21 described later.

  As shown in FIG. 1, the image processing apparatus 100 includes an A / D (Analog / Digital) converter 21, an image memory 22, a subtraction circuit 23, a filtering circuit 24, an affine transformation circuit 25, an LUT (Look). Up Table) 26, an imaging control circuit 27, a three-dimensional reconstruction circuit 31, a three-dimensional image processing circuit 32, a processing circuit 33, a display 40, and an input interface 50.

  The display 40 displays various types of information such as various images processed by the image processing apparatus 100 and GUI (Graphical User Interface). For example, the display 40 is a CRT (Cathode Ray Tube) monitor or a liquid crystal monitor.

  Here, the display 40 is a display dedicated to stereoscopic viewing that can display a stereoscopic image that can be stereoscopically viewed based on the image data for the left eye and the image data for the right eye. For example, the display 40 has a structure in which a lenticular sheet in which a plurality of substantially semi-cylindrical lenses such as kamaboko are arranged on a display surface or a fly-eye lens composed of a number of lenses such as fly-eye is attached. Therefore, it is possible to observe a stereoscopic image with the naked eye by changing the light trajectory with the lens without using the glasses dedicated to stereoscopic viewing. The display 40 may not be a display dedicated to autostereoscopic viewing. In such a case, the display 40 is a display that is synchronized with the glasses dedicated to stereoscopic viewing, and the time during which the image data for the left eye is displayed is transmitted only on the left side of the glasses, and the right side is not transmitted. Conversely, during the time when the image data for the right eye is displayed, only the right side of the glasses is transmitted and the left side is not transmitted. Alternatively, the display 40 has a structure in which a polarizing filter is attached to the display surface. For example, even-numbered pixel lines are horizontally polarized and odd-numbered pixel lines are vertically polarized. Stereo glasses are designed to transmit only horizontally polarized light on the left eye side and only vertically polarized light on the right eye side, and image data for the left eye on the even pixel lines and right eye image on the odd pixel lines. Display data. In this way, stereoscopic vision X-ray image data is displayed by using the glasses dedicated for stereoscopic vision. Note that the image data for the left eye and the image data for the right eye are defined by the parallax angle.

  The input interface 50 corresponds to an input device such as a mouse, a keyboard, a button, a panel switch, a touch command screen, a foot switch, a trackball, and a joystick. The input interface 50 receives various instructions from the operator and appropriately transfers the received various instructions to each circuit of the image processing apparatus 100.

  For example, the input interface 50 includes an X-ray trigger button for instructing X-ray irradiation. When the X-ray trigger button is pressed by the operator, the X-ray diagnostic apparatus 1 starts capturing X-ray image data. Further, for example, the input interface 50 includes an apparatus drive button for instructing a change in the X-ray irradiation direction. When the device driving button is pressed by the operator, the X-ray diagnostic apparatus 1 changes the X-ray irradiation direction by rotating the C-arm 13 in a preset direction.

  The A / D converter 21 is connected to the detector 12, converts the analog signal input from the detector 12 into a digital signal, and stores the converted digital signal in the image memory 22 as X-ray image data.

  The image memory 22 stores X-ray image data. The image memory 22 stores reconstruction data (volume data) reconstructed by a 3D reconstruction circuit 31 described later and a 3D image generated by the 3D image processing circuit 32. The image memory 22 can store a program that can be executed by a computer.

  The subtraction circuit 23 generates differential image data such as DSA (Digital Subtraction Angiography) image data. For example, the subtraction circuit 23 generates DSA image data using mask image data and contrast image data stored in the image memory 22, or volume data having a blood vessel structure using two volume data. Here, the mask image data corresponds to X-ray image data (non-contrast image data) captured before the contrast agent is injected. The contrast image data corresponds to X-ray image data (contrast image data) imaged while injecting a contrast agent.

  The filtering circuit 24 performs image processing filtering such as high-pass filtering and low-pass filtering. The affine transformation circuit 25 performs enlargement, reduction, and movement of the image. The LUT 26 stores a table for performing gradation conversion.

  The imaging control circuit 27 controls various processes related to imaging by the X-ray imaging mechanism 10 under the control of the processing circuit 33 described later. For example, the imaging control circuit 27 controls rotational imaging that captures an X-ray image at a predetermined frame rate while rotating the C-arm 13. For example, the imaging control circuit 27 controls rotational imaging of X-ray image data a plurality of times after a single contrast agent injection, triggered by a signal output from the injector 60 at the start of contrast agent injection. Here, the imaging control circuit 27 controls the start of a plurality of times of rotational imaging based on the elapsed time starting from the injection start time of a single contrast agent, and thereby the timing at which the contrast agent reaches each rotational imaging target. Rotate imaging in accordance with.

  In addition, the imaging control circuit 27 controls a high voltage generator (not shown) while rotating the C-arm 13 to generate X-rays continuously or intermittently from the X-ray tube 11, thereby detecting the detector. 12 is controlled to detect X-rays transmitted through the subject P. Here, the imaging control circuit 27 generates X-rays from the X-ray tube 11 based on the X-ray generation conditions set for each rotational imaging by the processing circuit 33 described later. In other words, the X-ray imaging mechanism 10 as an imaging mechanism includes an X-ray tube that generates X-rays and a detector that detects X-rays, and at least the X-ray tube is arranged so that the observation direction by X-rays is variable. Hold it movable. The imaging control circuit 27 as an imaging control unit controls the observation direction by the imaging mechanism and the imaging by the X-ray tube and the detector.

  The three-dimensional reconstruction circuit 31 reconstructs reconstruction data (volume data) from X-ray images collected by rotational imaging by the X-ray imaging mechanism 10. For example, the three-dimensional reconstruction circuit 31 uses the subtraction circuit 23 to generate the rotated X-ray image data as the mask image data and the X-ray image whose angle substantially matches the mask image data in the rotated X-ray image as the contrast image. Volume data having a blood vessel structure is reconstructed from the post-subtraction projection data that has been subtracted and stored by the image memory 22. Alternatively, the three-dimensional reconstruction circuit 31 reconstructs the volume data separately using the rotated X-ray image data as the mask image data and the rotated X-ray image data as the contrast image data stored in the image memory 22. Volume data having a blood vessel structure is generated by subtracting the two volume data. Then, the three-dimensional reconstruction circuit 31 stores the reconstructed volume data in the image memory 22.

  The three-dimensional image processing circuit 32 generates three-dimensional medical image data from the volume data stored by the image memory 22. For example, the three-dimensional image processing circuit 32 generates volume rendering image data and MPR (Multi Planar Reconstruction) image data from the volume data. Then, the 3D image processing circuit 32 stores the generated 3D medical image data in the image memory 22. The three-dimensional image processing circuit 32 refers to the LUT 26 and performs gradation conversion of the three-dimensional medical image data.

  The processing circuit 33 controls the entire X-ray diagnostic apparatus 1. Specifically, the processing circuit 33 controls various processes relating to imaging of X-ray image data by the X-ray imaging mechanism 10, generation of a display image, display of a display image on the display 40, and the like. For example, the processing circuit 33 generates three-dimensional image data from rotational imaging by the X-ray imaging mechanism 10 or X-ray image data captured by rotational imaging, and displays the three-dimensional image data on the display 40.

  Further, the processing circuit 33 executes a parametric image generation function 333 and a display control function 334 as shown in FIG. Here, for example, each processing function executed by the parametric image generation function 333 and the display control function 334 which are components of the processing circuit 33 shown in FIG. 1 is an X-ray diagnostic apparatus in the form of a program executable by a computer. 1 storage device (for example, the image memory 22). The processing circuit 33 is a processor that realizes a function corresponding to each program by reading each program from the storage device and executing the program. In other words, the processing circuit 33 in a state where each program is read has each function shown in the processing circuit 33 of FIG.

  The content illustrated in FIG. 1 is merely an example. For example, FIG. 1 shows a plurality of circuits (processors) of a subtraction circuit 23, a filtering circuit 24, an affine transformation circuit 25, an imaging control circuit 27, a three-dimensional reconstruction circuit 31, a three-dimensional image processing circuit 32, and a processing circuit 33. However, these circuits are not necessarily configured independently. For example, any circuit among these circuits may be appropriately combined.

  The term “processor” used in the above description is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an application specific integrated circuit (ASIC), a programmable logic device (for example, It means circuits such as a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), and a field programmable gate array (FPGA). The processor implements a function by reading and executing a program stored in the storage circuit. Instead of storing the program in the storage circuit, the program may be directly incorporated in the processor circuit. In this case, the processor realizes the function by reading and executing the program incorporated in the circuit. Note that each processor of the present embodiment is not limited to being configured as a single circuit for each processor, but may be configured as a single processor by combining a plurality of independent circuits to realize the function. Good. Furthermore, a plurality of components in each figure may be integrated into one processor to realize the function.

  Heretofore, an example of the configuration of the X-ray diagnostic apparatus 1 according to the first embodiment has been described. In the X-ray diagnostic apparatus 1 having such a configuration, the processing circuit 33 includes a DSA image generation function 331, a warping processing function 332, and a parametric image generation function 333 in order to easily provide a stereoscopic image for parametric imaging. And the display control function 334.

  That is, the DSA image generation function 331 generates first difference image data by subtracting the first non-contrast image data corresponding to the first observation direction from the first contrast image data corresponding to the first observation direction. Further, the DSA image generation function 331 calculates a second difference image by subtracting the second non-contrast image data corresponding to the second observation direction from the second contrast image data corresponding to the second observation direction different from the first observation direction. Generate data. The DSA image generation function 331 is an example of a difference image generation unit. The DSA image generation function 331 is an example of a blood vessel image generation unit.

  Subsequently, the warping processing function 332 uses the blood vessel shape drawn in the reference image data serving as a reference among the first difference image data and the second difference image data as a reference, and the blood vessel shape drawn in image data other than the reference image data. A deformation process for deforming is executed. The warping processing function 332 is an example of an image processing unit.

  Subsequently, the parametric image generation function 333 uses the image data after the deformation process, the first color image data corresponding to the first observation direction and assigned with the color according to the temporal change of the pixel value, and the first color image data The second color image data to which the color corresponding to the temporal change of the pixel value is assigned corresponding to the two observation directions is generated. The parametric image generation function 333 is an example of a color image generation unit.

  Then, the display control function 334 displays a stereoscopic image based on the first color image data and the second color image data. Thereby, the X-ray diagnostic apparatus 1 can easily provide a stereoscopic image of parametric imaging. The display control function 334 is an example of a display control unit.

  Each function executed by the processing circuit 33 is set in advance as, for example, an X-ray parametric imaging imaging program (hereinafter also referred to as “imaging program”). For example, the parallax angle is registered in advance in the imaging program. The parallax angle is an angle for determining the positions of two viewpoints (observation angle 1 and observation angle 2) set for performing stereo observation.

  For example, when the C-arm 13 is set at an angle of RAO30CRA0, RAO30CRA0 is rotated at observation angle 1, and RAO35CRA0 obtained by further rotating the observation angle 1 to the right by 5 degrees becomes observation angle 2. This rotation direction is preferably changed according to the traveling direction of the blood vessel to be observed. Therefore, an imaging program may be prepared for each rotation direction, or a GUI for determining the direction may be provided in the imaging program, and the rotation direction may be determined using the GUI. For example, when the joystick is tilted to the right, the C-arm 13 is moved to the LAO direction when tilted to the left, to the RAO direction when tilted to the left, to the CRA when tilted upward, and to the CAU when tilted downward. Rotate 5 degrees in the direction (the angle does not change and the direction of rotation changes). Specifically, when the joystick is tilted upward from the RAO 30 CRA 0 as the starting point, the RAO 30 CRA 0 is set to the observation angle 1, and the RAO 30 CRA 5 rotated 5 degrees upward from the RAO 30 CRA 0 is set to the observation angle 2. Alternatively, when the joystick is tilted to the right starting from the RAO 30 CRA 0, the RAO 30 CRA 0 is set to the observation angle 1, and the RAO 25 CRA 0 rotated 5 degrees to the left from the RAO 30 CRA 0 is set to the observation angle 2. Here, for the sake of clarity of explanation, the case where the joystick is tilted in either the up-down direction or the left-right direction has been described. However, for example, a combination of arbitrary directions (a combination of the upper direction and the right direction) (Oblique direction) may be designated as the rotation direction.

  FIG. 3 is a flowchart showing a processing procedure of the X-ray diagnostic apparatus 1 according to the first embodiment. The processing procedure shown in FIG. 3 is executed, for example, in an Angio examination or intervention treatment. In the first embodiment, a case will be described in which a target part such as a cerebral blood vessel is less affected by body movement.

  As shown in FIG. 3, the processing circuit 33 determines whether or not it is a processing timing (step S101). For example, when an instruction to start the imaging program is input by the operator, the processing circuit 33 determines that the processing timing is reached, and executes the processing after step S102. If step S101 is negative, the processing circuit 33 does not start imaging and the following processing is in a standby state.

  Subsequently, the processing circuit 33 moves the C-arm 13 to the observation angle 2 (step S102). Next, the DSA image generation function 331 executes DSA image generation processing (step S103). In the DSA image generation process, first DSA image data and second DSA image data are generated. The first DSA image data represents DSA image data corresponding to the observation angle 1. The second DSA image data represents DSA image data corresponding to the observation angle 2. DSA image data (subtraction image data) is an example of difference image data. DSA image data is an example of blood vessel image data.

  The DSA image generation process will be described with reference to FIGS. 4, 5A, and 5B. FIG. 4 is a flowchart showing a processing procedure of DSA image generation processing according to the first embodiment. FIG. 4 illustrates a processing procedure corresponding to the DSA image generation processing in step S102 illustrated in FIG. 5A and 5B are diagrams for explaining the DSA image generation processing according to the first embodiment. In FIG. 5A, the horizontal axis corresponds to time, and the vertical axis corresponds to the contrast agent injection amount. In FIG. 5B, the horizontal axis corresponds to time. In FIG. 5B, a circle represents DSA image data at that time.

  As shown in FIG. 4, the DSA image generation function 331 determines whether or not the X-ray imaging switch (X-ray trigger button) has been pressed (step S201). For example, when the X-ray imaging switch is pressed by the operator (Yes at Step S201), the DSA image generation function 331 starts the processing after Step S202. Until the X-ray trigger button is pressed (No at Step S201), the DSA image generation function 331 does not start the processing after Step S202. By this time, it is preferable that the operator prepares to inject the contrast agent, such as filling the contrast agent in a syringe.

  When the X-ray imaging switch is pressed by the operator, the DSA image generation function 331 collects second mask image data (step S202). The second mask image data represents mask image data corresponding to the observation angle 2. For example, the DSA image generation function 331 controls the imaging system devices such as the X-ray tube 11 and the detector 12 and collects the second mask image data of the number set in advance in the imaging program. The number of second mask image data may be one or plural. The number of second mask image data is set according to the noise level required for the mask image data. The number of second mask image data is preset in the imaging program. Then, the DSA image generation function 331 moves the C-arm 13 to the observation angle 1 (step S203).

  Then, the DSA image generation function 331 collects the first mask image data (step S204). The first mask image data represents mask image data corresponding to the observation angle 1. For example, the DSA image generation function 331 collects the first mask image data by the same process as the process of step S202.

  Then, the DSA image generation function 331 notifies the start of injection of the contrast agent (step 205. For example, the DSA image generation function 331 displays an icon indicating the injection start timing on the screen of the display 40, thereby the contrast agent. However, the present invention is not limited to this, and the notification of the start of injection may be performed by audio output, or a countdown indicating the timing of the start of injection may be displayed. The injection of the contrast medium is started using a syringe, or the injection of the contrast medium may be automatically started after the completion of the collection of the first mask image data using the injector 60.

  Then, the DSA image generation function 331 collects first contrast image data of a plurality of time phases at a predetermined frame rate (step S206). The first contrast image data represents contrast image data corresponding to the observation angle 1.

  As shown in FIG. 5A, for example, the DSA image generation function 331 starts collecting the first contrast image data at a frame rate of 10 fps. Then, the DSA image generation function 331 captures a total of seven pieces of first contrast image data at t1, t2, t3, t4, t5, t6, and t7. The frame rate for collecting the first contrast image data is preferably changed according to the blood flow velocity of the target site (target site). For example, 60 fps is set at a site where blood flow is fast, and 6 fps is set at a site where blood flow is slow.

  Then, the DSA image generation function 331 generates a plurality of time-phase first DSA image data (step S207). As shown in FIG. 5B, for example, the DSA image generation function 331 controls the subtraction circuit 23 to subtract the first mask image data from each of the seven first contrast image data corresponding to t1 to t7 (subtraction). Thus, seven first DSA image data corresponding to t1 to t7 are generated. Here, when there are a plurality of first mask image data, it is preferable to average the plurality of first mask image data to generate the first mask image data with reduced noise. . The generated first DSA image data is displayed on the display 40 in substantially real time by the display control function 334.

  Then, the DSA image generation function 331 moves the C-arm 13 to the observation angle 2 (step S208). For example, the operator observes the first DSA image data displayed on the display 40, and still has a sufficient contrast agent remaining in the blood vessel (artery), and the observation angle change switch at the timing when the target site is imaged. Press. As a result, the DSA image generation function 331 temporarily stops the X-ray irradiation and moves the C-arm 13 to the observation angle 2.

  Then, the DSA image generation function 331 collects at least one second contrast image data (step S209). As shown in FIG. 5A, for example, the DSA image generation function 331 images one piece of second contrast image data corresponding to t8 immediately after the C-arm 13 moves to the observation angle 2. One second contrast image data is sufficient as long as the blood vessel shape is depicted, but a plurality of second contrast image data may be captured in order to reduce noise. However, it is preferable to limit the number of images to about 3 even when capturing a plurality of images. Note that imaging by the DSA image generation function 331 is controlled by the imaging control circuit 27. In other words, the imaging control circuit 27 captures a plurality of time-series first contrast image data in a state where the observation direction by the imaging mechanism is set to the first observation direction, and after the imaging of the first contrast image data, At least one second contrast image data is imaged in the second observation direction. For example, the imaging control circuit 27 captures a plurality of first contrast image data during a predetermined time from the start of the injection of the contrast medium, moves the second contrast direction after the predetermined time has elapsed from the start of the injection of the contrast medium, and performs the injection At least one second contrast image data is captured immediately after or before the end.

  Then, the DSA image generation function 331 generates second DSA image data (step S210). As shown in FIG. 5B, for example, the DSA image generation function 331 controls the subtraction circuit 23 to subtract the second mask image data from one second contrast image data corresponding to t8, thereby to t8. One corresponding second DSA image data is generated. Here, when there are a plurality of second mask image data, it is preferable to average the plurality of second mask image data to generate second mask image data with reduced noise. . Further, when there are a plurality of pieces of second contrast image data, it is preferable to average the plurality of pieces of second contrast image data and generate second contrast image data with reduced noise. The generated second DSA image data is displayed on the display 40 by the display control function 334 in substantially real time.

  In other words, the DSA image generation function 331 as the blood vessel image generation unit generates a plurality of first blood vessel image data based on the plurality of first contrast image data, and based on at least one second contrast image data. At least one second blood vessel image data is generated. For example, the DSA image generation function 331 generates a plurality of first blood vessel image data by subtracting the first non-contrast image data having the first observation direction as the observation direction from each of the plurality of first contrast image data. . Further, the DSA image generation function 331 subtracts the second non-contrast image data having the second observation direction as the observation direction from each of the at least one second contrast image data, thereby obtaining at least one second blood vessel image data. Generate.

  Then, the DSA image generation function 331 transfers the first DSA image data and the second DSA image data having a plurality of time phases to the image memory 22 (step S211). For example, the DSA image generation function 331 transfers (stores) seven first DSA image data corresponding to t1 to t7 and one second DSA image data corresponding to t8 to the image memory 22.

  Note that the processing procedure illustrated in FIG. 4 is merely an example, and is not necessarily limited to the illustrated example. For example, the order of the processing procedures shown in FIG. 4 can be arbitrarily changed within a range in which there is no contradiction in processing contents. For example, the process of generating the first DSA image data (Step S207) may be executed simultaneously with the process of generating the second DSA image data (Step S210). Further, the process of transferring DSA image data (step S211) may be performed in parallel with the process of generating DSA image data (steps S207 and 210).

  FIG. 4 illustrates the case where the observation angle change (step S208) after the injection of the contrast agent is performed by an instruction from the operator (pressing the observation angle change switch), but is not limited thereto. . For example, immediately after the injection of the contrast medium is completed, it is considered that sufficient contrast medium remains in the blood vessel and the target site is imaged. Therefore, the C-arm 13 may be automatically moved to the observation angle 2 after a certain time (for example, after 5 seconds) after the notification of the start of contrast agent injection (step S205). Here, since the time required for injecting the contrast agent largely depends on the amount of contrast agent to be injected, it may be set in advance according to the amount of contrast agent and the target site. In addition, when the contrast medium is injected using the injector 60, the C-arm 13 may be automatically moved to the observation angle 2 a predetermined time before the contrast medium injection end time. This fixed time is preferably changed according to the blood flow velocity of the target site (target site). For example, it is set to 3 seconds at a site where the blood flow is fast, and is set to 1 second at a site where the blood flow is slow. That is, the DSA image generation function 331 collects the first contrast image data of a plurality of time phases from the start of the injection of the contrast agent, and moves in the second observation direction before the predetermined time elapses from the end of the injection of the contrast agent. Collect image data. In other words, the DSA image generation function 331 as the blood vessel image generation unit generates a plurality of time-series first blood vessel image data having the first observation direction as the observation direction, and sets the second observation direction as the observation direction. At least one second blood vessel image data is generated. For example, the imaging control circuit 27 images the first contrast image data of a plurality of time phases from the start of the injection of the contrast agent, and moves in the second observation direction before a predetermined time elapses from the end of the injection of the contrast agent. Image data.

  The contents shown in FIGS. 5A and 5B are merely examples, and are not necessarily limited to the illustrated examples. For example, the number of first DSA image data and second DSA image data to be generated is not limited to the illustrated example, and can be set to an arbitrary number.

  Returning to the description of FIG. When the first DSA image data and the second DSA image data are generated, the warping process function 332 executes a warping process (step S104). The warping processing function 332 executes a warping process for matching the blood vessel shape of the other image data with the blood vessel shape serving as a reference among the blood vessel shapes drawn in the first DSA image data and the second DSA image data. The warping process is an example of a deformation process.

  The warping process will be described with reference to FIGS. 6, 7A, and 7B. FIG. 6 is a flowchart illustrating a processing procedure of the warping process according to the first embodiment. FIG. 6 illustrates a processing procedure corresponding to the warping process of step S104 illustrated in FIG. 7A and 7B are diagrams for explaining the warping process according to the first embodiment. 7A and 7B, the horizontal axis corresponds to time. 7A and 7B, white circles represent DSA image data at that time, and black circles represent deformed image data at that time. The deformed image data represents image data deformed by warping processing.

  As shown in FIGS. 6 and 7A, the warping processing function 332 calculates a movement function (movement vector) using the first DSA image data at t7 and the second DSA image data at t8 (step S301). Here, the movement function represents a positional relationship in which each pixel is moved in order to match the blood vessel shape drawn in one image data with the other blood vessel shape. For example, the warping processing function 332 calculates a transfer function by performing local pattern matching between the first DSA image data at t7 and the second DSA image data at t8. Note that a maximum movement amount corresponding to the parallax angle is determined for the movement function, and a matching search exceeding the maximum movement amount is not performed. As a result, the calculation time can be shortened, and at the same time, an impossible matching result can be prevented.

  Subsequently, the warping processing function 332 deforms the blood vessel shape of each first DSA image data to match the blood vessel shape of the second DSA image data (reference image data) by using a movement function (step S302). As shown in FIG. 7B, for example, the warping processing function 332 uses the calculated movement function to deform each of the seven first DSA image data corresponding to t1 to t7, thereby corresponding to 7 corresponding to t1 to t7. A piece of deformed image data is generated. In other words, the warping processing function 332 is based on the blood vessel shape in at least one of the plurality of first blood vessel image data and the blood vessel shape in at least one of the at least one second blood vessel image data. A plurality of third blood vessel image data corresponding to respective time phases of the plurality of first blood vessel image data are generated by deforming a plurality of one blood vessel image data, with the second observation direction being the observation direction. . The deformed image data corresponding to the observation direction 2 is an example of third blood vessel image data.

  Then, the warping processing function 332 transfers the deformed image data having a plurality of time phases to the image memory 22 (step S303). For example, the warping processing function 332 transfers each of the seven pieces of modified image data corresponding to t1 to t7 to the image memory 22.

  Note that the processing procedure illustrated in FIG. 6 is merely an example, and is not necessarily limited to the illustrated example. For example, the process of transferring deformed image data (step S303) may be executed in parallel with the process of generating deformed image data (step S302).

  Returning to the description of FIG. When the deformed image data of a plurality of time phases is generated, the parametric image generation function 333 generates two parametric image data with different viewpoints (step S105). For example, the parametric image generation function 333 generates the first parametric image data and the second parametric image data by using the first blood vessel image data and the third blood vessel image data, respectively. The first parametric image data represents parametric image data corresponding to the observation direction 1. The second parametric image data represents parametric image data corresponding to the observation direction 2. Parametric image data is an example of color image data.

  For example, the parametric image generation function 333 generates first parametric image data using seven pieces of first DSA image data corresponding to t1 to t7. Further, the parametric image generation function 333 generates second parametric image data using the seven pieces of modified image data corresponding to t1 to t7.

  Specifically, the parametric image generation function 333 identifies the inflow time using the seven first DSA image data corresponding to t1 to t7. Here, the inflow time is a parameter defined on the basis of a time-series change of each pixel value by regarding a change in pixel value at each position of the DSA image data as a change in contrast agent concentration. As an inflow time identification method, any identification method can be selected from TTP (Time-to-Peak) and TTA (Time-to-Arrival). For example, TTP is a method of identifying a time at which a pixel value has a maximum time change as an inflow time. TTA is a method of identifying, as an inflow time, a time at which a time change of a pixel value reaches a predetermined value, or a time at which a predetermined ratio with respect to a maximum value in the time change of the pixel value is reached.

  When the inflow time is identified, the parametric image generation function 333 generates first parametric image data as a still image by assigning a color corresponding to the inflow time to each pixel position. The process for generating the second parametric image data is the same as the process for generating the first parametric image data except that the inflow time is identified using seven pieces of modified image data corresponding to t1 to t7. Therefore, explanation is omitted. Alternatively, instead of creating seven pieces of deformed image data, the inflow time obtained from the first DSA image data may be assigned to the inflow time obtained from the second DSA image data using a transfer function. In this case, the warping process only needs to be performed once, so that the processing time can be shortened. That is, the parametric image generation function 333 generates the first parametric image data using the first DSA image data having a plurality of time phases. The warping processing function 332 executes the deformation process based on the blood vessel shape drawn in the second DSA image data as the reference image data on the first parametric image data, thereby corresponding to the second observation direction. The second parametric image data is generated.

  As described above, the parametric image generation function 333 generates the first parametric image data and the second parametric image data. In other words, the parametric image generation function 333 generates first color image data that reflects the flow of the contrast agent, with the first observation direction as the observation direction, using a plurality of at least a plurality of first blood vessel image data. At the same time, the second color image data reflecting the flow of the contrast agent is generated with the second observation direction as the observation direction by using a plurality of at least a plurality of third blood vessel image data. The first parametric image data and the second parametric image data are not limited to still images and may be generated as moving images. For example, the parametric image generation function 333 uses the parametric imaging moving image display method described in, for example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2014-200396), for example, as the first parametric image data and the second parametric image data as moving images. May be generated.

  Then, the display control function 334 displays a stereoscopic image using two parametric image data with different viewpoints (step S106). For example, the display control function 334 displays a stereoscopic image on the display 40 using the first parametric image data and the second parametric image data.

  When the parallax angle is not in the left-right direction of the patient, when displaying the first parametric image data and the second parametric image data, it is necessary to rotate the first parametric image data and the second parametric image data using the affine transformation circuit 25. become. The rotation process is performed so that the projection direction of the rotation axis is the vertical direction. For example, when rotating in the vertical direction, specifically, when the first observation angle is RAO30CRA0 and the second observation angle is RAO30CRA5, the first parametric image data and the second parametric image data are 90 degrees to the right or left Is displayed in a state rotated 90 degrees. Further, for example, when rotating from the lower right direction of the patient to the upper left direction of the patient, specifically, when the first observation angle is RAO2CRA2 and the second observation angle is LAO2CAU2, the first parametric image data and the second parametric image data are It is displayed in a manner rotated 45 degrees to the right or 135 degrees to the left. That is, the parametric image generation function 333 changes the rotation axis when moving from the first observation direction to the second observation direction from the focal position of the X-ray tube when imaged from each observation direction to the detector position at that time. A rotation axis projection image that can be projected as if it was photographed is obtained, and first color image data and second color image data are generated so that the rotation axis projection image is directed vertically.

  Although an example of rotating parametric image data has been described here, the FPD may be rotated so that a similar parametric image can be obtained instead of rotating parametric image data. That is, the DSA image generation function 331 changes the rotation axis when moving from the first observation direction to the second observation direction from the focal position of the X-ray tube when imaged from each observation direction to the detector position at that time. A rotation axis projection image that can be projected as if it was taken is obtained, and the detector is rotated so that the rotation axis projection image is directed in the vertical direction, so that two-way contrast image data and two-way non-contrast image data are obtained. Generate. That is, the DSA image generation function 331 rotates the detector so that the rotation axis projection image is directed in the vertical direction, and the first contrast image data, the first non-contrast image data, the second contrast image data, and the second Non-contrast image data is generated.

  As described above, in the X-ray diagnostic apparatus 1 according to the first embodiment, the DSA image generation function 331 includes a plurality of time-phase first contrast image data collected from the start of contrast agent injection. From the first mask image data, the first DSA image data having a plurality of time phases is generated. The DSA image generation function 331 generates at least one second DSA image data by subtracting the second mask image data from at least one second contrast image data collected after collecting the first contrast image data. To do. The warping processing function 332 executes the deformation process based on the blood vessel shape drawn in the second DSA image data as the reference image data on the first DSA image data in a plurality of time phases, thereby corresponding to the second observation direction. A plurality of time phase modified image data is generated. The parametric image generation function 333 generates first parametric image data using the first DSA image data of a plurality of time phases, and generates second parametric image data using the deformed image data of the plurality of time phases. Alternatively, the parametric image generation function 333 generates second parametric image data by transforming the first parametric image data.

  That is, the X-ray diagnostic apparatus 1 according to the first embodiment performs a warping process for artificially generating time-series DSA image data in the other observation direction from time-series DSA image data in one observation direction. Run. According to this, the X-ray diagnostic apparatus 1 according to the first embodiment can easily provide a stereoscopic image of parametric imaging. For example, since the X-ray diagnostic apparatus 1 can generate two parametric image data with different viewpoints by one injection of a contrast agent, a stereoscopic image can be easily provided.

(Second Embodiment)
In the first embodiment described above, the case where the target site is a site that is less affected by body movement, such as a cerebral blood vessel, is described, but the embodiment is not limited to this. For example, the X-ray diagnostic apparatus 1 can also set a site with body movement as a target site, such as an abdominal blood vessel or a heart. Therefore, in the second embodiment, a case will be described in which a body motion part is a target part.

  The X-ray diagnostic apparatus 1 according to the second embodiment has the same configuration as the X-ray diagnostic apparatus 1 illustrated in FIG. 1, and the processes of the DSA image generation function 331, the warping processing function 332, and the parametric image generation function 333 are performed. A part of is different. Therefore, in the second embodiment, the description will focus on the points that are different from the first embodiment, and the description of the points having the same functions as the configuration described in the first embodiment will be omitted.

  That is, the DSA image generation function 331 includes a first mask of a plurality of time phases collected from a site where a structure other than a blood vessel changes due to body movement while switching between the first observation direction and the second observation direction is repeatedly performed. A first contrast image of a plurality of time phases collected from a part where both the structure and the blood vessel shape other than the blood vessel are changed by body movement while collecting the image data and the second mask image data of the plurality of time phases, and then injecting a contrast medium Data and second contrast image data of a plurality of time phases are collected. Thereafter, first difference image data having a plurality of time phases and second difference image data having a plurality of time phases are generated. At this time, as the first contrast image data of a plurality of time phases, an optimum image is selected from the first mask image data of a plurality of time phases, and the difference process is performed. The optimal image may be determined based on an electrocardiogram, a respiratory waveform, or the like, or the optimal image may be identified by a method shown in Japanese Patent Application Laid-Open Nos. 2004-112469, 2005-198330, and 2007-215925. Also good. Similarly, as the second contrast image data of a plurality of time phases, an optimum image is selected from the second mask image data of a plurality of time phases, and a difference process is performed.

  Then, the warping processing function 332 generates a reference among the first difference image data of the plurality of time phases based on the similarity between the first difference image data of the plurality of time phases and the second difference image data of the plurality of time phases. And the second reference image data serving as a reference among the second difference image data of a plurality of time phases are determined as the reference image data. Then, the warping processing function 332 executes the deformation processing based on the blood vessel shape drawn in the determined first reference image data on the first difference image data of a plurality of time phases in the first observation direction. Corresponding multiple time phase first modified image data is generated. In addition, the warping processing function 332 executes the deformation processing based on the blood vessel shape drawn in the determined second reference image data on the second difference image data of a plurality of time phases, so that the second observation direction is obtained. Corresponding multiple time phase second deformation image data is generated.

  Then, the parametric image generation function 333 generates first parametric image data and first color image data using the first modified image data of a plurality of time phases, and uses the second modified image data of a plurality of time phases, Second parametric image data and second color image data are generated.

  The processing procedure of the X-ray diagnostic apparatus 1 according to the second embodiment is the same as the processing procedure illustrated in FIG. 3, but the processes of steps S103 and S104 are different. Hereinafter, a processing procedure of the X-ray diagnostic apparatus 1 according to the second embodiment will be described.

  A DSA image generation process according to the second embodiment will be described with reference to FIGS. 8 and 9. FIG. 8 is a flowchart showing a processing procedure of DSA image generation processing according to the second embodiment. FIG. 8 illustrates a processing procedure corresponding to the DSA image generation processing in step S103 illustrated in FIG. FIG. 9 is a diagram for explaining the DSA image generation processing according to the second embodiment. In FIG. 9, the horizontal axis corresponds to time. In FIG. 9, circles represent the DSA image data at that time.

  As shown in FIG. 8, the DSA image generation function 331 starts the reciprocating motion of the C-arm 13 (step S401). This reciprocating motion may be a case of moving alternately only between the observation angle 1 and the observation angle 2, or an overrun may be considered for the observation angle 1 and the observation angle 2, respectively. That is, when the observation angle 1 is RAO30CRA0 and the observation angle 2 is RAO35CRA0, the reciprocating motion may be performed between RAO25CRA0 and RAO40CRA0. When reciprocating only between the observation angle 1 and the observation angle 2, the time required for image collection is shortened. On the other hand, when the overrun is taken into consideration, the possibility that the C-arm 13 vibrates due to a sudden stop during image capture is reduced.

  When the reciprocating motion of the C-arm 13 is started, the DSA image generation function 331 collects the first mask image data and the second mask image data (step S402). Then, the DSA image generation function 331 repeatedly executes the collection in step S402 until it is determined that the collection has been performed for a predetermined time (No in step S403). Here, the collection time (predetermined time) is determined by the movement time of the target part (cycle of body movement) and the imaging interval. For example, the collection time is determined in consideration of collecting a sufficient number of image data for a body motion cycle and collecting image data in various states (phases). Specifically, if the movement is respiratory movement (body movement), the influence of the body movement returns to the original state (phase) in about 5 seconds. If the shooting interval is once every 0.5 seconds, 10 images can be collected before returning to the original position. Therefore, in the case of respiratory movement, it is preferable to collect mask image data for at least one cycle. In the case of a heartbeat, it returns to the original position (phase) in 1 second. In this case, if the imaging interval (frame rate) is set to 0.5 seconds, the heart with the same phase is always imaged. Therefore, the rotation speed is adjusted (slowed down) and set at an interval of 0.6 seconds. As a result, 5 or 6 images having different phases can be collected in about 3 seconds. For example, the collection time may be registered in advance in the imaging program for each target region, or may be designated by the operator each time.

  If it is determined that the data has been collected for a predetermined time (Yes at step S403), the DSA image generation function 331 notifies the start of contrast agent injection (step S404). For example, the DSA image generation function 331 notifies the start of the injection of the contrast agent by displaying an icon indicating the injection start timing on the screen of the display 40. However, the present invention is not limited to this, and the notification of the injection start may be performed by voice output, or a countdown indicating the timing of the injection start may be displayed. Thereby, the operator starts injecting the contrast medium using the syringe. Alternatively, the contrast agent may be manually injected by a doctor using a syringe.

  Then, the DSA image generation function 331 collects the first contrast image data and the second contrast image data (step S405). Then, the DSA image generation function 331 repeatedly executes the collection in step S405 until the imaging is completed (No in step S406). Here, since the collection time and the frame rate are the same as those in step S402, the description thereof is omitted. The collected first contrast image data and second contrast image data are displayed on the display 40 by the display control function 334 in substantially real time. Then, for example, while observing the contrast image data displayed on the display 40, the operator finishes imaging at the timing when sufficient contrast agent still remains in the blood vessel (artery) and the target site is contrasted. The collected contrast image data is transferred to the image memory 22. Note that the transfer of the contrast image data may be performed in parallel with the collection.

  When the imaging is completed (Yes at Step S406), the DSA image generation function 331 generates first DSA image data having a plurality of time phases and second DSA image data having a plurality of time phases (Step S407). For example, the DSA image generation function 331 generates the first DSA image data using the first contrast image data and the first mask image data collected at the same observation angle 1. At this time, the DSA image generation function 331 generates the first DSA image data using a combination of the first contrast image data having the same tissue position and the first mask image data.

  An example of a specific method will be introduced here. First, a MinIP image is created from each of first mask image data having a plurality of time phases and first contrast image data having a plurality of time phases. The MinIP image of the first mask image data is an image in which the minimum value in the first mask image data of a plurality of time phases is obtained for each pixel and the minimum value is used as the pixel value. When the MinIP image of the first contrast image data is calculated in the same manner, difference image data is generated between the MinIP image of the first contrast image data and the MinIP image of the first mask image data. This difference image data is an image representing the movement of blood vessels. A threshold value process is performed on the difference image data to extract a blood vessel moving region. Next, for each image data of the first contrast image data of a plurality of time phases, an optimal time phase mask image data is identified from the first mask image data of the plurality of time phases. For example, a plurality of difference image data is generated from first contrast image data of a specific time phase and first mask image data of a plurality of time phases. The sum of squares of the pixel values of the difference image data is calculated in areas other than the previously identified blood vessel moving region. The first mask image data having the smallest calculated sum of squares is the optimal first mask image data of the first contrast image data in the target time phase. The first DSA image data is generated by performing the same processing on the first contrast image data of all time phases.

  Then, the DSA image generation function 331 transfers the first DSA image data having a plurality of time phases and the second DSA image data having a plurality of time phases to the image memory 22 (step S408). The transfer of the first DSA image data and the second DSA image data may be performed in parallel with the generation of the first DSA image data and the second DSA image data. In other words, the DSA image generation function 331 as the blood vessel image generation unit generates a plurality of time-series first blood vessel image data having the first observation direction as the observation direction, and sets the second observation direction as the observation direction. A plurality of time-series second blood vessel image data is generated.

  Here, the DSA image data of each time phase generated by the DSA image generation function 331 is in a state where errors due to body movement remain. For example, as shown in FIG. 9, motion artifacts (artifacts caused by subtraction) due to motion are reduced in the DSA image data of each time phase of t1, t2, t3, t4, t5, t6, t7, and t8. However, between the DS1 image data at t1 and the DSA image data at t3, the displacement of the blood vessel is not reduced, and it can be said that the blood vessel shape depicted in each image data includes the displacement. Therefore, the following warping process is executed in order to reduce the positional deviation between a plurality of time phases at the same observation angle.

  The warping process according to the second embodiment will be described with reference to FIGS. 10, 11A, 11B, and 11C. FIG. 10 is a flowchart illustrating a processing procedure of the warping process according to the second embodiment. FIG. 10 illustrates a processing procedure corresponding to the warping process in step S103 illustrated in FIG. 11A, 11B, and 11C are diagrams for explaining the warping process according to the second embodiment. In FIGS. 11A, 11B, and 11C, the horizontal axis corresponds to time. In FIGS. 11A, 11B, and 11C, white circles represent DSA image data at that time, and black circles represent deformed image data at that time.

  As shown in FIG. 10 and FIG. 11A, the warping processing function 332 is based on the similarity between the first DSA image data having a plurality of time phases and the second DSA image data having a plurality of time phases. Second reference image data is determined (step S501). As a result, the warping processing function 332 extracts a combination of DSA image data in which the blood vessel shape is uniform between the observation angle 1 and the observation angle 2.

  Specifically, the warping processing function 332 includes the DSA image data similarity between “t1” and “t2”, and the DSA image data similarity between “t1” and “t4”, “t1”. DSA image data similarity between “t6” and “t6”, and DSA image data similarity between “t1” and “t8”. Further, the warping processing function 332 includes the DSA image data similarity between “t3” and “t2”, the DSA image data similarity between “t3” and “t4”, and “t3” and “t6”. DSA image data similarity between "t3" and DSA image data similarity between "t3" and "t8". In addition, the warping processing function 332 includes the DSA image data similarity between “t5” and “t2”, the DSA image data similarity between “t5” and “t4”, “t5” and “t6”. DSA image data similarity between “t5” and DSA image data similarity between “t5” and “t8”. Further, the warping processing function 332 includes the DSA image data similarity between “t7” and “t2”, the DSA image data similarity between “t7” and “t4”, “t7” and “t6”. DSA image data similarity between "t7" and DSA image data similarity between "t7" and "t8".

  Then, the warping processing function 332 compares the calculated similarities. Here, for example, when the DSA image data similarity between “t3” and “t6” is the highest, it is considered that the blood vessel shapes rendered in these image data are aligned. In this case, the warping processing function 332 determines the first DSA image data at t3 as the first reference image data, and determines the second DSA image data at t6 as the second reference image data.

  Subsequently, as shown in FIG. 11B, the warping processing function 332 calculates a transfer function using each first DSA image data and first reference image data (step S502A). Specifically, the warping processing function 332 includes a transfer function between “t1” and “t3”, a transfer function between “t3” and “t5”, and “t3” and “t7”. And a transfer function between them.

  Then, as shown in FIG. 11C, the warping processing function 332 uses each movement function to transform the blood vessel shape of each first DSA image data to match the blood vessel shape of the first reference image data (step S503A). . Specifically, the warping processing function 332 uses the transfer function between “t1” and “t3” to deform the first DSA image data of “t1”, thereby converting the deformed image data of “t1”. Generate. Further, the warping processing function 332 generates the deformed image data of “t5” by deforming the first DSA image data of “t5” using a transfer function between “t3” and “t5”. Further, the warping processing function 332 generates the deformed image data of “t7” by deforming the first DSA image data of “t7” using the transfer function between “t3” and “t7”.

  As described above, the warping processing function 332 generates first modified image data having a plurality of time phases. The first modified image data represents modified image data corresponding to the observation direction 1. As a result, the blood vessel shapes rendered in the DSA image data at t1, t3, t5, and t7 at the observation angle 1 are aligned. In other words, the warping processing function 332 as an image processing unit deforms other image data of the plurality of first blood vessel image data with reference to at least one of the plurality of first blood vessel image data. Then, a plurality of time-series third blood vessel image data having the first observation direction as the observation direction are generated. That is, the first DSA image data at t3 and the first deformed image data at t1, t5, and t7 are examples of a plurality of time-series third blood vessel image data.

  Then, the warping processing function 332 causes the third blood vessel image data having a plurality of time phases to be transferred to the image memory 22 (step S504A). The transfer of the third blood vessel image data may be performed in parallel with the generation of the third blood vessel image data.

  In step S502B to step S504B, the warping processing function 332 as the image processing unit uses another image of the plurality of second blood vessel image data as a reference, based on at least one of the plurality of second blood vessel image data. By deforming the data, a plurality of time-series fourth blood vessel image data with the second observation direction as the observation direction is generated. That is, in FIG. 11C, the second DSA image data at t6 and the second deformed image data at t2, t4, and t8 are examples of a plurality of time-series fourth blood vessel image data. Note that the processes in steps S502B to S504B are the same as the processes in steps S502A to S504A except that the processes are related to image data corresponding to the observation angle 2, and thus the description thereof is omitted.

  As described above, the warping processing function 332 aligns the blood vessel shapes drawn in the DSA image data (deformed image data) from t1 to t8.

  Then, the parametric image generation function 333 generates two parametric image data with different viewpoints using each DSA image data (deformed image data) of t1 to t8. For example, the parametric image generation function 333 generates the first parametric image data by using the third blood vessel image data (first modified image data) in each time phase of t1, t3, t5, and t7. In addition, the parametric image generation function 333 generates second parametric image data using the fourth blood vessel image data (second modified image data) in each time phase of t2, t4, t6, and t8. In other words, the parametric image generation function 333 serving as the color image generation unit generates the first color image data reflecting the flow of the contrast agent with the first observation direction as the observation direction based on the plurality of third blood vessel image data. Generate. In addition, the parametric image generation function 333 generates second color image data reflecting the flow of the contrast agent with the second observation direction as the observation direction based on the plurality of fourth blood vessel image data.

  As described above, the X-ray diagnostic apparatus 1 according to the second embodiment executes the warping process for artificially aligning different blood vessel shapes at the respective observation angles. As a result, the X-ray diagnostic apparatus 1 according to the second embodiment allows two parametric image data with different viewpoints to be injected by one injection of a contrast medium even when a target part is a part with periodic movement. Since it can generate | occur | produce, a stereoscopic vision image can be provided easily.

  In the second embodiment, the periodic movement is described as an example, but the embodiment is not limited to this. For example, the X-ray diagnostic apparatus 1 according to the second embodiment can obtain a stereoscopic view by collecting a sufficient number of contrast image data and mask image data even in a region that is affected by a non-periodic motion. Images can be provided.

(Modification of the second embodiment)
In the second embodiment, the blood vessel shapes of the first DSA image data and the second DSA image data are deformed to match the blood vessel shapes of the first reference image data and the second reference image data, respectively. However, the X-ray diagnostic apparatus 1 according to the second embodiment adds the blood vessel shapes of the first DSA image data and the second DSA image data to the blood vessel shapes of the second reference image data and the first reference image data, respectively. May be deformed. This process doubles the warping process and takes time, but the time resolution can be improved in generating two parametric image data.

  Processing of the X-ray diagnostic apparatus 1 according to the modification of the second embodiment will be described with reference to FIG. FIG. 12 is a diagram for explaining processing of the X-ray diagnostic apparatus 1 according to a modification of the second embodiment. The X-ray diagnostic apparatus 1 according to the modification of the second embodiment executes a process described in FIG. 12 in addition to the processes described in FIGS. 11A to 11C.

  As shown in FIG. 12, in the X-ray diagnostic apparatus 1, the warping processing function 332 calculates a movement function using each second DSA image data and the first reference image data. Specifically, the warping processing function 332 includes a transfer function between “t2” and “t3”, a transfer function between “t3” and “t4”, and “t3” and “t6”. And a transfer function between “t3” and “t8” are calculated.

  Then, the warping processing function 332 transforms the blood vessel shape of each second DSA image data so as to match the blood vessel shape of the first reference image data by using each movement function. Specifically, the warping processing function 332 uses the transfer function between “t2” and “t3” to deform the second DSA image data of “t2”, thereby “t2 corresponding to the observation angle 1”. ”Is generated. Further, the warping processing function 332 uses the transfer function between “t3” and “t4” to deform the second DSA image data of “t4”, thereby deforming “t4” corresponding to the observation angle 1. Generate image data. Further, the warping processing function 332 uses the transfer function between “t3” and “t6” to deform the second DSA image data of “t6”, thereby deforming “t6” corresponding to the observation angle 1. Generate image data. Further, the warping processing function 332 uses the transfer function between “t3” and “t8” to deform the second DSA image data of “t8”, thereby deforming “t8” corresponding to the observation angle 1. Generate image data. Accordingly, the warping processing function 332 can generate image data (DSA image data or modified image data) corresponding to the observation angle 1 for each of t1, t2, t3, t4, t5, t6, t7, and t8. it can.

  Similarly, the warping processing function 332 generates DSA image data corresponding to the observation angle 2. That is, the warping processing function 332 calculates a transfer function using each first DSA image data and second reference image data. Then, the warping processing function 332 deforms the blood vessel shape of each first DSA image data so as to match the blood vessel shape of the second reference image data by using each movement function. Thereby, the warping processing function 332 can generate image data corresponding to the observation angle 2 for each of t1, t2, t3, t4, t5, t6, t7, and t8.

  That is, the warping processing function 332 executes the deformation process based on the blood vessel shape drawn in the determined first reference image data on the first difference image data and the second difference image data of a plurality of time phases. The first modified image data having a plurality of time phases corresponding to the first observation direction is generated. In addition, the warping processing function 332 executes the deformation process based on the blood vessel shape drawn in the determined second reference image data on the first difference image data and the second difference image data in a plurality of time phases. The second deformed image data having a plurality of time phases corresponding to the second observation direction is generated.

  Thus, the X-ray diagnostic apparatus 1 according to the modified example of the second embodiment can improve the time resolution. For example, in FIGS. 11A to 11C, the case where image data for four time phases (DSA image data or modified image data) is generated in each observation direction has been described. In each observation direction, the X-ray diagnostic apparatus 1 according to the modification of the second embodiment performs the process described in FIG. 12 in addition to the processes described in FIGS. 11A to 11C. Image data for 8 time phases is generated. For this reason, the X-ray diagnostic apparatus 1 according to the modification of the second embodiment can improve the time resolution.

(Third embodiment)
In the third embodiment, a case will be described in which X-ray image data at the observation angle 1 and the observation angle 2 is collected by the vibration of the C-shaped arm 13.

  The X-ray diagnostic apparatus 1 according to the third embodiment has the same configuration as the X-ray diagnostic apparatus 1 illustrated in FIG. 1, further includes an acceleration sensor, a DSA image generation function 331, a warping processing function 332, And part of the processing of the parametric image generation function 333 is different. Therefore, in the third embodiment, description will be made mainly on points different from the first embodiment, and description of points having the same functions as those of the configuration described in the first embodiment will be omitted.

  That is, the DSA image generation function 331 collects a plurality of data collected while the first observation direction and the second observation direction are repeatedly switched by the vibration of the C-arm 13 that supports the X-ray tube 11 and the X-ray detector 12. Using the first contrast image data in the time phase and the second contrast image data in the plurality of time phases, first difference image data in the plurality of time phases and second difference image data in the plurality of time phases are generated.

  Then, the warping processing function 332 uses the first reference image data serving as a reference among the first difference image data of a plurality of time phases and the second reference image data serving as a reference among the second difference image data of a plurality of time phases. Determined as reference image data. Then, the warping processing function 332 executes the deformation processing based on the blood vessel shape drawn in the determined first reference image data on the first difference image data of a plurality of time phases in the first observation direction. Corresponding multiple time phase third blood vessel image data is generated. In addition, the warping processing function 332 executes the deformation process based on the blood vessel shape drawn in the determined fourth result image data on the second difference image data of a plurality of time phases, thereby causing the second observation direction. Corresponding multiple time phase second deformation image data is generated.

  The parametric image generation function 333 generates first color image data using the first modified image data of a plurality of time phases, and uses the second modified image data of the plurality of time phases to convert the second color image data. Generate.

  Processing of the X-ray diagnostic apparatus 1 according to the third embodiment will be described with reference to FIGS. 13A, 13B, 13C, and 13D. 13A, 13B, 13C, and 13D are diagrams for explaining processing of the X-ray diagnostic apparatus 1 according to the third embodiment. In FIG. 13A, FIG. 13B, FIG. 13C, and FIG. 13D, the horizontal axis corresponds to time, white circles represent DSA image data at that time, and black circles represent deformed image data at that time.

  As illustrated in FIG. 13A, the DSA image generation function 331 alternately collects X-ray image data at the observation angle 1 and the observation angle 2 by the vibration of the C-arm 13. For example, the DSA image generation function 331 causes the C-type arm 13 to vibrate by driving a motor for rotation while applying a brake to the rotation of the C-type arm 13. Alternatively, the DSA image generation function 331 vibrates the C-type arm 13 by performing a sudden stop while rotating the C-type arm 13 at a high speed.

  When vibration occurs, the acceleration sensor provided in the C-type arm 13 detects peaks and valleys of vibration. For example, the acceleration sensor identifies a position where the acceleration of the C-type arm 13 is 0 (or minimal) as a mountain and a valley. Then, the DSA image generation function 331 collects mask image data at the identified peaks and valleys. In other words, the imaging control circuit 27 performs imaging while repeatedly changing the observation direction by the imaging mechanism between the first observation direction and the second observation direction, and thereby a plurality of time-series first contrast image data. A plurality of time-series second contrast image data are captured. Specifically, the imaging control circuit 27 performs imaging while repeatedly changing the observation direction by the imaging mechanism between the first observation direction and the second observation direction by vibrating the imaging mechanism.

  Note that the method of detecting the peaks and valleys of vibration is not limited to the acceleration sensor. For example, vibration peaks and valleys may be detected by an angle sensor or a position sensor. For example, the angle sensor and the position sensor measure the amount of change at short intervals such as 0.1 seconds, and are almost stationary (vibration valley and mountain) when the measured amount of change is below a certain value. judge. When the collection of the mask image data is completed, the DSA image generation function 331 notifies the start of contrast agent injection. As a result, the operator starts injecting the contrast medium. The DSA image generation function 331 collects contrast image data while the vibration of the C-arm 13 continues. Then, while observing the contrast image data displayed on the display 40, the operator ends imaging at the timing when the sufficient contrast agent still remains in the blood vessel (artery) and the target site is contrasted, The collected contrast image data is transferred to the image memory 22. Note that the transfer of the contrast image data may be performed in parallel with the collection.

  When imaging is completed, the DSA image generation function 331 generates first DSA image data using the first contrast image data and the first mask image data collected at the same observation angle 1. At this time, the DSA image generation function 331 generates the first DSA image data using a combination of the first contrast image data and the first mask image data with a small error due to vibration. Since the combination identification method of the first contrast image data and the first mask image data with little error due to vibration has been described in the second embodiment, the description thereof is omitted here. In addition, after identifying the first mask image data that matches the first contrast image data, the matching first mask image data is compared with the first contrast image data for the purpose of further reducing artifacts, and a movement function (movement vector) is compared. The first DSA image data may be generated after the matching first mask image data is transformed. As a result, a parametric image with little influence of artifacts can be created, which has an advantage of facilitating observation. The second DSA image data is generated in the same manner. In other words, the DSA image generation function 331 as the blood vessel image generation unit generates a plurality of first blood vessel image data based on the plurality of first contrast image data, and a plurality of the plurality of first contrast image data based on the plurality of second contrast image data. The second blood vessel image data is generated. The DSA image generation function 331 generates a plurality of first blood vessel image data by subtracting non-contrast image data corresponding to the first contrast image data from each of the plurality of first contrast image data, and generates a plurality of second contrast images. A plurality of second blood vessel image data is generated by subtracting non-contrast image data corresponding to the second contrast image data from each of the image data.

  As shown in FIG. 13A, the DSA image generation function 331 collects the first DSA image data in each time phase of t1, t3, t5, and t7, and in each time phase of t2, t4, t6, and t8, Collect 2DSA image data. Here, since these DSA image data are collected while the C-arm 13 vibrates, a slight change in the observation angle causes deformation of the blood vessel shape due to the influence of vibration attenuation or the like. Born. In other words, the DSA image generation function 331 as the blood vessel image generation unit generates a plurality of second blood vessel image data in time series.

  Then, as illustrated in FIG. 13B, the DSA image generation function 331 determines the first reference image data and the second reference image data. For example, the operator selects a frame in which the artery is most appropriately depicted in the first DSA image data and a frame in which the artery is most appropriately depicted in the second DSA image data. The DSA image generation function 331 determines the image data of the frame selected by the operator as the first reference image data and the second reference image data. Note that the first reference image data and the second reference image data may be automatically determined as image data estimated to be less blurred by checking the intensity of the high frequency component by Fourier transform of the image data.

  Then, as illustrated in FIG. 13C, the warping processing function 332 calculates a transfer function using each first DSA image data and first reference image data. Specifically, the warping processing function 332 includes a transfer function between “t1” and “t5”, a transfer function between “t3” and “t5”, and “t5” and “t7”. And a transfer function between them.

  Then, as illustrated in FIG. 13D, the warping processing function 332 deforms the blood vessel shape of each first DSA image data to match the blood vessel shape of the first reference image data by using the respective movement functions. Specifically, the warping processing function 332 uses the transfer function between “t1” and “t5” to deform the first DSA image data of “t1”, thereby converting the deformed image data of “t1”. Generate. Further, the warping processing function 332 generates deformed image data of “t3” by deforming the first DSA image data of “t3” using a transfer function between “t3” and “t5”. Further, the warping processing function 332 generates deformed image data of “t7” by deforming the first DSA image data of “t7” using a transfer function between “t5” and “t7”.

  As described above, the warping processing function 332 generates first modified image data having a plurality of time phases. Thereby, the observation angles drawn in the DSA image data at t1, t3, t5, and t7 at the observation angle 1 are aligned. Note that the second modified image data is also generated by the same processing as the first modified image data. In other words, the warping processing function 332 as an image processing unit generates third blood vessel image data by performing deformation processing on the plurality of first blood vessel image data, and performs deformation processing on the plurality of second blood vessel image data. Thus, the fourth blood vessel image data is generated.

  Then, the warping processing function 332 transfers the first modified image data having a plurality of time phases and the second modified image data having a plurality of time phases to the image memory 22. The transfer of the deformed image data may be performed in parallel with the generation of the deformed image data.

  Then, the parametric image generation function 333 generates first parametric image data by using the third blood vessel image data (first modified image data) of each time phase of t1, t3, t5, and t7. In addition, the parametric image generation function 333 generates second parametric image data using the fourth blood vessel image data (second modified image data) in each time phase of t2, t4, t6, and t8.

(Modification of the third embodiment)
In the third embodiment, as in the modification of the second embodiment, the blood vessel shapes of the first DSA image data and the second DSA image data are changed to the blood vessel shapes of the first reference image data and the second reference image data. It may be deformed. This process doubles the warping process and takes time, but the time resolution can be improved in generating two parametric image data.

  The process of the X-ray diagnostic apparatus 1 according to the modification of the third embodiment will be described with reference to FIG. FIG. 14 is a diagram for explaining processing of the X-ray diagnostic apparatus 1 according to a modification of the third embodiment. The X-ray diagnostic apparatus 1 according to the modification of the third embodiment executes a process described in FIG. 14 in addition to the processes described in FIGS. 13A to 13D.

  As shown in FIG. 14, in the X-ray diagnostic apparatus 1, the warping processing function 332 calculates a movement function using each second DSA image data and first reference image data. Specifically, the warping processing function 332 includes a transfer function between “t2” and “t5”, a transfer function between “t4” and “t5”, and “t5” and “t6”. And a transfer function between “t5” and “t8”.

  Then, the warping processing function 332 transforms the blood vessel shape of each second DSA image data so as to match the blood vessel shape of the first reference image data by using each movement function. Specifically, the warping processing function 332 uses the transfer function between “t2” and “t5” to deform the second DSA image data of “t2”, thereby “t2 corresponding to the observation angle 1”. ”Is generated. Further, the warping processing function 332 uses the transfer function between “t4” and “t5” to deform the second DSA image data of “t4”, thereby deforming “t4” corresponding to the observation angle 1. Generate image data. Further, the warping processing function 332 uses the transfer function between “t5” and “t6” to deform the second DSA image data of “t6”, thereby deforming “t6” corresponding to the observation angle 1. Generate image data. Further, the warping processing function 332 uses the transfer function between “t5” and “t8” to deform the second DSA image data of “t8”, thereby deforming “t8” corresponding to the observation angle 1. Generate image data. As a result, the warping processing function 332 generates third blood vessel image data (DSA image data or deformed image data) corresponding to the observation angle 1 for each of t1, t2, t3, t4, t5, t6, t7, and t8. can do. The deformed image data “t2,” “t4,” “t6,” and “t8” corresponding to the observation angle 1 is an example of third blood vessel image data. That is, the warping processing function 332 as the image processing unit is based on the blood vessel shape in at least one of the plurality of first blood vessel image data and the blood vessel shape in at least one of the plurality of second blood vessel image data. A plurality of fourth blood vessel images corresponding to respective time phases of the plurality of first blood vessel image data, with the first observation direction being the observation direction by deforming a plurality of the plurality of first blood vessel image data. Generate data.

  Similarly, the warping processing function 332 generates fourth blood vessel image data corresponding to the observation angle 2. That is, the warping processing function 332 calculates a transfer function between each first DSA image data and the second reference image data and a transfer function between each second DSA image data and the second reference image data. Then, the warping processing function 332 uses the respective movement functions to transform the blood vessel shapes of the first DSA image data and the second DSA image data to match the blood vessel shapes of the second reference image data and the first reference image data, respectively. Let Thereby, the warping processing function 332 can generate image data corresponding to the observation angle 2 for each of t1, t2, t3, t4, t5, t6, t7, and t8. The deformed image data of “t1”, “t3”, “t5”, and “t7” corresponding to the observation angle 2 is an example of third blood vessel image data. That is, the warping processing function 332 as the image processing unit is based on the blood vessel shape in at least one of the plurality of first blood vessel image data and the blood vessel shape in at least one of the plurality of second blood vessel image data. A plurality of third blood vessel images corresponding to respective time phases of the plurality of first blood vessel image data, with the second observation direction being set as the observation direction by deforming a plurality of the plurality of first blood vessel image data. Generate data.

  That is, the warping processing function 332 executes the deformation process based on the blood vessel shape drawn in the determined first reference image data on the first difference image data and the second difference image data of a plurality of time phases. The first modified image data having a plurality of time phases corresponding to the first observation direction is generated. In addition, the warping processing function 332 executes the deformation process based on the blood vessel shape drawn in the determined second reference image data on the first difference image data and the second difference image data in a plurality of time phases. The second deformed image data having a plurality of time phases corresponding to the second observation direction is generated.

  Thus, the X-ray diagnostic apparatus 1 according to the modification of the third embodiment can improve the time resolution. For example, in FIGS. 11A to 11C, the case where image data for four time phases is generated in each observation direction has been described. In each observation direction, the X-ray diagnostic apparatus 1 according to the modification of the second embodiment performs the process described in FIG. 12 in addition to the processes described in FIGS. 11A to 11C. Image data for 8 time phases is generated. For this reason, the X-ray diagnostic apparatus 1 according to the modification of the second embodiment can improve the time resolution.

  That is, the parametric image generation function 333 as a color image generation unit generates first color image data based on a plurality of third blood vessel image data. The parametric image generation function 333 generates second color image data based on a plurality of the plurality of fourth blood vessel image data.

  Furthermore, in the third embodiment, when the shooting time is sufficiently short and shooting is finished before the vibration is attenuated, the warping process may not be performed. This has the advantage that the processing time can be significantly reduced.

  As described above, the X-ray diagnostic apparatus 1 according to the third embodiment can easily generate a stereoscopic image even when collecting X-ray image data of the observation angle 1 and the observation angle 2 by the vibration of the C-arm 13. Can be provided.

(Other embodiments)
In addition to the above-described embodiment, various other forms may be implemented.

(Blood vessel image data)
In the above-described embodiment, the case where parametric imaging is performed using DSA image data has been described. However, the present invention is not limited to this. For example, the above-described embodiment can be applied when parametric imaging is performed using blood vessel image data. The DSA image data is an example of blood vessel image data.

  For example, the processing circuit 33 executes a blood vessel image generation function instead of the DSA image generation function 331. The blood vessel image generation function generates blood vessel image data by one of the following two methods. The blood vessel image generation function is an example of a blood vessel image generation unit.

  The first method is a method of generating blood vessel image data by machine learning. In machine learning, a learned model for obtaining an output from an input is generated by supervised learning using learning data with contrast image data as input and DSA image data as output. When contrast image data is input, the learned model generates blood vessel image data in which background components (bone tissue, soft tissue, etc.) other than blood vessels (contrast medium) are removed from the contrast image data. When the first method is used, the blood vessel image generation function includes the learned model described above. That is, the blood vessel image generation function generates the first blood vessel image data corresponding to the observation angle 1 by inputting the first contrast image data corresponding to the observation angle 1 to the learned model. The blood vessel image generation function generates second blood vessel image data corresponding to the observation angle 2 by inputting second contrast image data corresponding to the observation angle 2 to the learned model. The generated first blood vessel image data and second blood vessel image data can be used instead of the first DSA image data and the second DSA image data of the above-described embodiment.

  The second method is a method for generating blood vessel image data by extracting high-frequency components from contrast image data. In this case, the blood vessel image generation function generates low frequency component image data in which low frequency components (soft tissue or the like) of the contrast image data are extracted by applying a low pass filter to the contrast image data (filter processing). . The blood vessel image generation function generates high-frequency component image data in which the high-frequency component (contrast agent component) of the contrast image data is extracted by subtracting the low-frequency component image data from the original contrast image data (subtraction processing). To do. The high frequency component image data can be used as blood vessel image data. That is, the blood vessel image generation function generates the first blood vessel image data corresponding to the observation angle 1 by executing the above filtering process and subtraction process on the first contrast image data corresponding to the observation angle 1. Further, the blood vessel image generation function generates the second blood vessel image data corresponding to the observation angle 2 by executing the filtering process and the subtraction process on the second contrast image data corresponding to the observation angle 2. The generated first blood vessel image data and second blood vessel image data can be used instead of the first DSA image data and the second DSA image data of the above-described embodiment.

  Further, each component of each illustrated apparatus is functionally conceptual, and does not necessarily need to be physically configured as illustrated. In other words, the specific form of distribution / integration of each device is not limited to the one shown in the figure, and all or a part of the distribution / integration is functionally or physically distributed in arbitrary units according to various loads or usage conditions. Can be integrated and configured. Further, all or a part of each processing function performed in each device may be realized by a CPU and a program analyzed and executed by the CPU, or may be realized as hardware by wired logic.

  In addition, among the processes described in the above embodiment, all or a part of the processes described as being automatically performed can be manually performed, or the processes described as being manually performed All or a part of the above can be automatically performed by a known method. In addition, the processing procedure, control procedure, specific name, and information including various data and parameters shown in the above-described document and drawings can be arbitrarily changed unless otherwise specified.

  The image processing method described in the above embodiment can be realized by executing a prepared image processing 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. The image processing program can also be executed by being recorded on a computer-readable recording medium such as a hard disk, a flexible disk (FD), a CD-ROM, an MO, or a DVD, and being read from the recording medium by the computer. .

  Moreover, in said embodiment, substantially real time refers to performing each process immediately, whenever each data used as a process target generate | occur | produces. That is, the real time includes not only a case where the time when the subject is imaged and the time when the image is displayed completely matches, but also a case where the image is displayed with a slight delay depending on the time required for the image generation processing.

  According to at least one embodiment described above, a stereoscopic image of parametric imaging can be easily provided.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 X-ray diagnostic apparatus 33 Processing circuit 331 DSA image generation function 332 Warping processing function 333 Parametric image generation function 334 Display control function

Claims (14)

A blood vessel image generation unit that generates a plurality of time-series first blood vessel image data having the first observation direction as the observation direction, and generates at least one second blood vessel image data having the second observation direction as the observation direction; ,
Of the plurality of first blood vessel image data, based on a blood vessel shape in at least one of the plurality of first blood vessel image data and a blood vessel shape in at least one of the at least one second blood vessel image data. An image processing unit that generates a plurality of third blood vessel image data corresponding to respective time phases of the plurality of first blood vessel image data, wherein the second observation direction is an observation direction ,
Using at least a plurality of the plurality of first blood vessel image data, the first color image data reflecting the flow of the contrast agent is generated with the first observation direction as the observation direction, and at least the plurality of the second blood vessel image data is used. A color image generation unit that generates a second color image data that reflects the flow of the contrast agent, using a plurality of the three blood vessel image data, the second observation direction being the observation direction;
A display control unit that causes a display unit to display a stereoscopic image based on the first color image data and the second color image data;
An X-ray diagnostic apparatus comprising: An imaging mechanism including an X-ray tube that generates X-rays and a detector that detects the X-rays, and at least movably holds the X-ray tube so that an observation direction by the X-rays is variable;
An imaging control unit that controls the observation direction by the imaging mechanism and imaging by the X-ray tube and the detector;
Further comprising
The imaging control unit
A plurality of time-series first contrast image data is imaged in a state where the observation direction by the imaging mechanism is set to the first observation direction, and observation by the imaging mechanism is performed after the imaging of the first contrast image data Changing the direction to the second observation direction and capturing at least one second contrast image data;
The blood vessel image generation unit generates the plurality of first blood vessel image data based on the plurality of first contrast image data, and the at least one second contrast image data based on the at least one second contrast image data. Generating blood vessel image data,
The X-ray diagnostic apparatus according to claim 1. The blood vessel image generation unit
The first non-contrast image data having the first observation direction as an observation direction is subtracted from each of the plurality of first contrast image data to generate the plurality of first blood vessel image data, and the second Generating the at least one second blood vessel image data by subtracting the second non-contrast image data whose observation direction is the observation direction from each of the at least one second contrast image data;
The X-ray diagnostic apparatus according to claim 2. The imaging control unit captures the plurality of first contrast image data during a predetermined time from the start of contrast medium injection, and moves in the second observation direction after a predetermined time has elapsed since the start of contrast medium injection. Capturing at least one second contrast image data;
The X-ray diagnostic apparatus according to claim 3. The imaging control unit captures first contrast image data of a plurality of time phases from the start of contrast agent injection, and moves in the second observation direction after the contrast agent injection ends or before a predetermined time elapses. Imaging contrast image data,
The X-ray diagnostic apparatus according to claim 3. The blood vessel image generation unit generates a plurality of the second blood vessel image data in time series,
The image processing unit includes a plurality of second blood vessels based on a blood vessel shape in at least one of the plurality of first blood vessel image data and a blood vessel shape in at least one of the plurality of second blood vessel image data. By deforming a plurality of pieces of image data, a plurality of fourth blood vessel image data corresponding to the respective time phases of the plurality of second blood vessel image data are generated with the first observation direction as the observation direction. ,
The color image generation unit generates the first color image data based on a plurality of the plurality of first blood vessel image data and a plurality of the plurality of fourth blood vessel image data, and the plurality of first blood image data Generating the second color image data based on a plurality of two blood vessel image data and a plurality of the plurality of third blood vessel image data;
The X-ray diagnostic apparatus according to claim 1. An imaging mechanism including an X-ray tube that generates X-rays and a detector that detects the X-rays, and at least movably holds the X-ray tube so that an observation direction by the X-rays is variable;
An imaging control unit that controls the observation direction by the imaging mechanism and imaging by the X-ray tube and the detector;
Further comprising
The imaging control unit performs imaging while repeatedly changing the observation direction by the imaging mechanism between the first observation direction and the second observation direction, thereby a plurality of time-series first contrast image data. A plurality of second contrast image data in time series,
The blood vessel image generation unit generates the plurality of first blood vessel image data based on the plurality of first contrast image data, and the plurality of second blood vessel images based on the plurality of second contrast image data. Generate data,
The X-ray diagnostic apparatus according to claim 6. The blood vessel image generation unit
From each of the plurality of first contrast image data, non-contrast image data corresponding to the first contrast image data is subtracted to generate a plurality of first blood vessel image data,
From each of the plurality of second contrast image data, non-contrast image data corresponding to the second contrast image data is subtracted to generate a plurality of second blood vessel image data,
The image processing unit
Generating the third blood vessel image data by performing a deformation process on the plurality of first blood vessel image data;
Generating the fourth blood vessel image data by subjecting the plurality of second blood vessel image data to deformation processing;
The X-ray diagnostic apparatus according to claim 7. The imaging control unit performs imaging while repeatedly changing the observation direction by the imaging mechanism between the first observation direction and the second observation direction by vibrating the imaging mechanism.
The X-ray diagnostic apparatus according to claim 7 or 8. A plurality of time-series first blood vessel image data having the first observation direction as the observation direction and a plurality of time-series second blood vessel image data having the second observation direction as the observation direction. A generator,
A time series in which the first observation direction is the observation direction by deforming other image data of the plurality of first blood vessel image data on the basis of at least one of the plurality of first blood vessel image data. A plurality of typical third blood vessel image data, and
A time series in which the second observation direction is the observation direction by deforming other image data of the plurality of second blood vessel image data on the basis of at least one of the plurality of second blood vessel image data. An image processing unit that generates a plurality of typical fourth blood vessel image data;
Based on the plurality of third blood vessel image data, first color image data reflecting the flow of the contrast agent is generated with the first observation direction as an observation direction, and based on the plurality of fourth blood vessel image data. A color image generation unit that generates second color image data reflecting the flow of the contrast agent, the second observation direction being the observation direction;
A display control unit that causes a display unit to display a stereoscopic image based on the first color image data and the second color image data;
An X-ray diagnostic apparatus comprising: A blood vessel image generation unit that generates a plurality of time-series first blood vessel image data having the first observation direction as the observation direction, and generates at least one second blood vessel image data having the second observation direction as the observation direction; ,
Of the plurality of first blood vessel image data, based on a blood vessel shape in at least one of the plurality of first blood vessel image data and a blood vessel shape in at least one of the at least one second blood vessel image data. An image processing unit that generates a plurality of third blood vessel image data corresponding to respective time phases of the plurality of first blood vessel image data, wherein the second observation direction is an observation direction ,
Using at least a plurality of the plurality of first blood vessel image data, the first color image data reflecting the flow of the contrast agent is generated with the first observation direction as the observation direction, and at least the plurality of the second blood vessel image data is used. A color image generation unit that generates a second color image data that reflects the flow of the contrast agent, using a plurality of the three blood vessel image data, the second observation direction being the observation direction;
A display control unit that causes a display unit to display a stereoscopic image based on the first color image data and the second color image data;
An image processing apparatus comprising: A plurality of time-series first blood vessel image data having the first observation direction as the observation direction and a plurality of time-series second blood vessel image data having the second observation direction as the observation direction. A generator,
A time series in which the first observation direction is the observation direction by deforming other image data of the plurality of first blood vessel image data on the basis of at least one of the plurality of first blood vessel image data. A plurality of typical third blood vessel image data, and
A time series in which the second observation direction is the observation direction by deforming other image data of the plurality of second blood vessel image data on the basis of at least one of the plurality of second blood vessel image data. An image processing unit that generates a plurality of typical fourth blood vessel image data;
Based on the plurality of third blood vessel image data, first color image data reflecting the flow of the contrast agent is generated with the first observation direction as an observation direction, and based on the plurality of fourth blood vessel image data. A color image generation unit that generates second color image data reflecting the flow of the contrast agent, the second observation direction being the observation direction;
A display control unit that causes a display unit to display a stereoscopic image based on the first color image data and the second color image data;
An image processing apparatus comprising: Generating a plurality of time-series first blood vessel image data having the first observation direction as the observation direction, and generating at least one second blood vessel image data having the second observation direction as the observation direction;
Of the plurality of first blood vessel image data, based on a blood vessel shape in at least one of the plurality of first blood vessel image data and a blood vessel shape in at least one of the at least one second blood vessel image data. A plurality of third blood vessel image data corresponding to respective time phases of the plurality of first blood vessel image data, and the second observation direction as the observation direction,
Using at least a plurality of the plurality of first blood vessel image data, the first color image data reflecting the flow of the contrast agent is generated with the first observation direction as the observation direction, and at least the plurality of the second blood vessel image data is used. Using a plurality of the three blood vessel image data, generating the second color image data reflecting the flow of the contrast agent, with the second observation direction as the observation direction,
Displaying a stereoscopic image based on the first color image data and the second color image data on a display unit;
An image processing program that causes a computer to execute each process. Generating a plurality of time-series first blood vessel image data with the first observation direction as the observation direction, and generating a plurality of time-series second blood vessel image data with the second observation direction as the observation direction,
A time series in which the first observation direction is the observation direction by deforming other image data of the plurality of first blood vessel image data on the basis of at least one of the plurality of first blood vessel image data. A plurality of typical third blood vessel image data,
A time series in which the second observation direction is the observation direction by deforming other image data of the plurality of second blood vessel image data on the basis of at least one of the plurality of second blood vessel image data. A plurality of typical fourth blood vessel image data,
Based on the plurality of third blood vessel image data, first color image data reflecting the flow of the contrast agent is generated with the first observation direction as an observation direction, and based on the plurality of fourth blood vessel image data. Generating second color image data reflecting the flow of the contrast agent, wherein the second observation direction is the observation direction;
Displaying a stereoscopic image based on the first color image data and the second color image data on a display unit;
An image processing program that causes a computer to execute each process.

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