JP7037810B2 - Image processing device, image processing program, and image processing method - Google Patents

Description

The present invention relates to an image processing apparatus, an image processing program, and an image processing method.

Endovascular treatment is a treatment for treating a lesion of a blood vessel using a treatment instrument inserted into a blood vessel (hereinafter referred to as "endovascular treatment instrument"). Usually, endovascular treatment is performed by operating an endovascular treatment instrument while viewing a transmission image (hereinafter referred to as "X-ray fluoroscopic image") obtained by a doctor (operator) performing surgery using X-rays. Will be.

The surgeon operates the endovascular treatment instrument by combining four types of operations: pushing (advancing), pulling (returning), rotating to the left, and rotating to the right. Therefore, the operator operates the endovascular treatment device for position information such as the distance from the insertion part of the endovascular treatment device to the lesion in the blood vessel and the bending angle / radius of the blood vessel to which the endovascular treatment device progresses. This is essential information for this.

Here, since the X-ray fluoroscopic image is a two-dimensional image, the operator cannot directly obtain information in the depth direction from the X-ray fluoroscopic image. Therefore, the surgeon operates the endovascular treatment instrument while imagining the above-mentioned position information by constructing a virtual three-dimensional structure of blood vessels in his / her own brain. However, in general, because the blood vessel has a complicated structure, the operator may misunderstand the position of the endovascular treatment device in the blood vessel while advancing the endovascular treatment device to the lesion. .. In this case, problems such as damage to the blood vessel by the endovascular treatment instrument are likely to occur.

In order to prevent the occurrence of such a problem, a technique for grasping the position and posture of the endovascular treatment device in the blood vessel by attaching a magnetic sensor to the endovascular treatment device has been proposed (for example, Patent Document 1). reference). In addition, a technique for grasping the position of the endovascular treatment device in the blood vessel from the three-dimensional data of the shape of the endovascular treatment device acquired in advance and the information such as the posture of the endovascular treatment device captured in the X-ray image. Has been proposed (see, for example, Patent Document 2).

Since the technique disclosed in Patent Document 1 attaches a magnetic sensor to an endovascular treatment instrument, it cannot deal with a lesion of a narrow blood vessel. The technique also requires a special device to read the position of the magnetic sensor in the operating room.

The technique disclosed in Patent Document 2 is different from the technique described in Patent Document 1, and can correspond to a lesion portion of a narrow blood vessel. However, in the field of endovascular treatment, the shape of the endovascular treatment instrument may be appropriately modified during the operation depending on the shape of the blood vessel and the like. Therefore, a special device is required in the operating room so that three-dimensional data on the shape of the endovascular treatment instrument can be acquired during the operation.

So far, a technique for grasping the position of an endovascular treatment instrument in a blood vessel has been proposed without the need for attaching a sensor to the endovascular treatment instrument or additionally arranging a special device in the operating room. (See, for example, Patent Document 3 and Patent Document 4).

Japanese Unexamined Patent Publication No. 2007-54246 Special Table 2017-507685 Japanese Unexamined Patent Publication No. 2011-50621 Japanese Unexamined Patent Publication No. 2006-167448

The technique disclosed in Patent Document 3 extracts a two-dimensional position of a surgical instrument (endovascular treatment instrument) from an X-ray fluoroscopic image, and determines the position where the extracted surgical instrument and the blood vessel extracted from the three-dimensional image overlap. It is estimated to be the position of the surgical instrument in the 3D image. In this estimation, the position of the extracted surgical tool is moved in parallel with the operator's line of sight on the three-dimensional image, and the position where the position of the surgical tool and the position of the blood vessel most coincide with each other, in other words, the position of the blood vessel 3 This is achieved by estimating the position where the surgical tool is most contained inside the 3D model as the position of the surgical tool on the 3D image.

This technology requires enormous calculations such as calculation of the imaging direction of the X-ray fluoroscopic image, calculation of the X-ray fluoroscopic image from the operator's line-of-sight direction, and estimation of the position of the surgical instrument in the three-dimensional image. In particular, the estimation of the position of the surgical tool in the 3D image determines whether or not the surgical tool is included in the 3D model of the blood vessel at one or more points on the 3D image. Therefore, the processing load required for the calculation is large.

The technique disclosed in Patent Document 4 identifies two coordinates (for example, X and Y coordinates) of an endovascular treatment device in the same direction by calculating the direction in which the fluoroscopic image is captured. Next, the technology is a three-dimensional model by narrowing down the candidates for blood vessels in which the endovascular treatment device is located on the axis perpendicular to the coordinates (X-ray irradiation axis) from multiple images acquired in time series. Estimate the position of the endovascular treatment device inside the.

The technique requires a time-series estimated position of the past endovascular treatment device in order to accurately estimate the position of the current endovascular treatment device inside the 3D model. Therefore, the processing load required for the calculation is large.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to reduce the processing load required for calculating the estimation of the position of the endovascular treatment device in the blood vessel.

The image processing apparatus according to the present invention stores the position information of the planar image of the tube formed by the radiation emitted from the radiation source passing through the tube and the position information of the stereoscopic image of the tube. A plane image and a three-dimensional image based on a storage unit, a shape line acquisition unit that acquires a shape line indicating the shape of a tube based on a three-dimensional image, position information of a plane image, and position information of a three-dimensional image. A registration part that aligns with, a plane position specifying part that specifies the position in the plane image of a moving body that moves inside the tube, a radiation source, and a moving body that specifies the position in the plane image. The position of the shortest point in the stereoscopic image of the moving object, which is the shortest distance from the shape line among the plurality of points included in the projection straight line and the projection straight line specifying part that specifies the projection straight line connecting It is characterized by having a three-dimensional position estimation unit for estimation.

According to the present invention, it is possible to reduce the processing load required for calculating the estimation of the position of the endovascular treatment device in the blood vessel.

It is a system block diagram which shows the embodiment of the image processing apparatus which concerns on this invention. It is a functional block diagram of the image processing apparatus of FIG. It is a schematic diagram which shows the center line of the blood vessel acquired by the shape line acquisition part provided in the image processing apparatus of FIG. It is a schematic diagram which shows the state which the position of the stereoscopic image of a blood vessel and the position of the plane image of a blood vessel are matched by the registration part provided in the image processing apparatus of FIG. It is a schematic diagram of the projection straight line specified by the projection straight line identification part provided in the image processing apparatus of FIG. It is a schematic diagram which shows the relationship between a center line and a projection straight line. It is a flowchart which shows the embodiment of the image processing method which concerns on this invention. It is a flowchart of the position determination processing which the image processing method of FIG. 7 has. It is a schematic diagram which shows the content of the estimation process executed in the position determination process of FIG. It is a schematic diagram which shows the relationship between the local coordinate system, the cross section of a blood vessel, and the shortest point at the shortest center point. It is a flowchart of the reliability determination processing which the image processing method of FIG. 7 has. It is a schematic diagram which shows the relationship between the blood vessel and the projection straight line in the reliability determination process of FIG. It is a schematic diagram which shows the example of the external apparatus controlled by the image processing apparatus of FIG. It is a schematic diagram which shows another example of the external apparatus controlled by the image processing apparatus of FIG.

Hereinafter, embodiments of the image processing apparatus, the image processing program, and the image processing method according to the present invention will be described with reference to the drawings.

The present invention is based on the distance between the shape line of the tube obtained from the stereoscopic image of the tube and the projected straight line connecting the source and the moving body whose position in the plane image is specified. It estimates the position of the moving object.

An embodiment described below is a guide wire that moves in a blood vessel by the image processing apparatus according to the present invention in the field of endovascular treatment using an X-ray irradiation device and an endovascular treatment device (for example, a guide wire). The content of the present invention will be described by taking as an example the case where the position is estimated and the same position is determined. That is, a blood vessel is an example of a tubular body in the present invention, a guide wire is an example of a moving body in the present invention, and an X-ray is an example of radiation in the present invention.

● Image processing equipment ●
First, the image processing apparatus according to the present invention will be described.

FIG. 1 is a system configuration diagram showing an embodiment of an image processing device (hereinafter referred to as “the device”) according to the present invention.

The figure shows that the present device 1, the X-ray irradiation device 2, and the stereoscopic image acquisition device 3 are connected to the image storage device 5 via the communication network 4. Further, the figure shows a state in which the present device 1 acquires an X-ray fluoroscopic image stored in the image storage device 5 from the X-ray irradiation device 2 and displays the X-ray fluoroscopic image on the display 6. show. Further, the figure shows that the blood vessel BV of the subject and the guide wire 7 moving in the blood vessel BV are displayed on the display 6, and the operator is operating the guide wire 7 while looking at the display 6.

The apparatus 1 estimates the position of the guide wire 7 in the blood vessel BV and determines the same position. The configuration and operation of the present device 1 will be described later.

The X-ray irradiation device 2 captures an X-ray fluoroscopic image of the blood vessel BV of the subject. The X-ray irradiation device 2 includes an X-ray source 21 and a screen 22. The X-ray source 21 irradiates X-rays. The screen 22 is a screen on which X-rays transmitted through the blood vessel BV of the subject are projected. The X-ray fluoroscopic image is an example of a planar image in the present invention in which X-rays emitted from the X-ray source 21 pass through the blood vessel BV and are formed on the screen 22. The fluoroscopic image is stored in the image storage device 5 via the communication network 4.

The stereoscopic image acquisition device 3 acquires a stereoscopic image of the blood vessel BV of the subject. The stereoscopic image acquisition device 3 is a device that acquires information inside a subject such as CT (Computed Tomography) or MRI (Magnetic Resonance Imaging) as an image. The stereoscopic image acquisition device 3 acquires a stereoscopic image of the blood vessel BV of the subject from the acquired information inside the subject. The stereoscopic image of the blood vessel BV of the subject is an example of the stereoscopic image of the tube body in the present invention.

The communication network 4 connects the apparatus 1, the X-ray irradiation device 2, the stereoscopic image acquisition device 3, and the image storage device 5, and realizes transmission / reception of an X-ray fluoroscopic image or a stereoscopic image between them. The communication network 4 is, for example, a LAN (Local Area Network).

The image storage device 5 stores an X-ray fluoroscopic image from the X-ray irradiation device 2 and a stereoscopic image from the stereoscopic image acquisition device 3. The image storage device 5 is, for example, a server or NAS (Network Attached Storage).

The display 6 is connected to the apparatus 1 and displays an X-ray fluoroscopic image, information based on control information from the apparatus 1, and the like. The display 6 is an example of an external device in the present invention. The control information will be described later.

The guide wire 7 is inserted into the blood vessel BV to guide the movement of the catheter (not shown) in the blood vessel BV.

The moving body in the present invention may be any endovascular treatment device inserted into the blood vessel, and is not limited to the guide wire. That is, for example, the moving body in the present invention may be a catheter, a stent, or a coil.

● Configuration of this device FIG. 2 is a functional block diagram of this device 1.
The apparatus 1 communicates with the storage unit 11, the shape line acquisition unit 12, the registration unit 13, the plane position specifying unit 14, the projection straight line specifying unit 15, the three-dimensional position estimation unit 16, and the determination unit 17. It has a portion 18 and.

The present device 1 is realized by a personal computer or the like. In the present apparatus 1, the information processing program according to the present invention (hereinafter referred to as “the present program”) operates, and the present program cooperates with the hardware resources of the present invention to process information according to the present invention described later. Realize the method (hereinafter referred to as "this method").

By having a computer (not shown) execute the program, the computer can function in the same manner as the device 1 and the computer can execute the method.

The storage unit 11 stores information necessary for the apparatus 1 to execute the method described later. The storage unit 11 is composed of, for example, a recording device such as an HDD (Hard Disk Drive) or SSD (Solid State Drive), a semiconductor memory element such as a RAM (Random Access Memory) or a flash memory, and the like.

The shape line acquisition unit 12 acquires the center line C1 of the blood vessel BV based on the stereoscopic image of the blood vessel BV. The center line C1 of the blood vessel BV is an example of a shape line showing the shape of the tubular body in the present invention. The shape line acquisition unit 12 acquires the center line C1 of the blood vessel BV from the stereoscopic image of the blood vessel BV by using a known thinning means such as a thinning algorithm.

The shape line acquisition unit 12 divides the center line C1 of the acquired blood vessel BV into a plurality of minute line segments (curves), and specifies the end points of each line segment as nodes connecting the line segments. As a result, the center line C1 includes a plurality of minute line segments and a plurality of nodes connecting the line segments.

The "small line segment" is, for example, an arc-shaped line segment having one radius of curvature.

The minute line segment may be a line segment obtained by evenly dividing the center line. That is, for example, the minute line segment may be a curved line segment having a plurality of radii of curvature.

FIG. 3 is a schematic diagram showing the center line C1 of the blood vessel BV acquired by the shape line acquisition unit 12.
In the figure, the black circle “●” indicates the node included in the center line C1, and the alternate long and short dash line indicates the outline of the stereoscopic image of the blood vessel BV. The figure shows that the center line C1 is divided into a plurality of minute line segments (curves), and the same line segments are connected by a plurality of nodes.

By dividing the center line C1 into a plurality of minute line segments in this way, the apparatus 1 can specify the local coordinate system at the end points (nodes) of each line segment and calculate the arc length parameter. .. The local coordinate system and arc length parameters will be described later.

Return to FIG.
The registration unit 13 performs positioning (registration) between the X-ray fluoroscopic image and the stereoscopic image based on the position information of the X-ray fluoroscopic image and the positional information of the stereoscopic image. The registration unit 13 extracts, for example, the position information of the contour line of the blood vessel BV in the X-ray fluoroscopic image and the position information of the contour line of the blood vessel BV in the stereoscopic image, and uses the extracted contour line position information. Based on this, the X-ray fluoroscopic image and the stereoscopic image are aligned. At this time, the registration unit 13 aligns the X-ray fluoroscopic image and the stereoscopic image by using, for example, a known 2D / 3D registration algorithm.

The "position information of the X-ray fluoroscopic image" and the "position information of the stereoscopic image" are, for example, information such as coordinates, brightness, and brightness assigned to pixels (pixels) constituting the image. The "position information of a stereoscopic image" is, for example, information such as coordinates assigned to so-called voxels constituting the image, brightness, and brightness.

FIG. 4 is a schematic diagram showing a state in which the position of the stereoscopic image and the position of the fluoroscopic image are aligned by the registration unit 13.
The figure shows a state in which the position (orientation) of the blood vessel BV in the stereoscopic image is aligned with the position of the blood vessel BV in the fluoroscopic image.

Return to FIG.
The plane position specifying portion 14 acquires the position of the guide wire 7 moving inside the blood vessel BV in the fluoroscopic image. The plane position specifying unit 14 acquires the position of the guide wire 7 in the fluoroscopic image by using a known image processing algorithm such as template matching.

The projection straight line specifying unit 15 is one of the X-ray source 21 of the X-ray irradiation device 2 and a part of the guide wire 7 whose position in the X-ray fluoroscopic image is specified (that is, one of the guide wires 7 projected on the screen 22). Part) and a straight line connecting them (hereinafter referred to as "projected straight line") C2 is specified. In the present embodiment, the projection straight line specifying portion 15 identifies the projection straight line C2 connecting the X-ray source 21 and the tip end portion 71 of the guide wire 7 in the traveling direction of the guide wire 7.

The projection straight line specifying unit 15 divides the specified projection straight line C2 into a plurality of minute line segments (straight lines), and sets the end points of each line segment as nodes connecting the line segments. As a result, the projected straight line C2 includes a plurality of minute line segments and a plurality of nodes connecting the line segments.

The projected straight line specifying portion in the present invention may specify the projected straight line according to the type and shape of the endovascular treatment instrument. That is, for example, the projection straight line specifying portion in the present invention may specify a straight line connecting the radiation source and a portion (unevenness, hole, etc.) characteristic of the shape of the endovascular treatment device as a projection straight line.

FIG. 5 is a schematic diagram of the projection straight line C2 specified by the projection straight line specifying unit 15.
In the figure, the black squares “■” indicate the nodes included in the projection straight line C2. The figure shows that the projection straight line C2 is divided into a plurality of minute line segments (straight lines), and the same line segments are connected by a plurality of nodes.

Return to FIG.
The stereoscopic position estimation unit 16 estimates the position of the endovascular treatment instrument (tip portion 71) in the stereoscopic image. The method of estimating the position of the tip portion 71 in the stereoscopic image will be described later.

The determination unit 17 determines whether or not the position estimated by the stereoscopic position estimation unit 16 is the position in the stereoscopic image (inside the blood vessel BV) of the endovascular treatment instrument (tip portion 71). The method for determining the position of the tip portion 71 will be described later.

The shape line acquisition unit 12, the registration unit 13, the plane position identification unit 14, the projection straight line identification unit 15, the stereoscopic position estimation unit 16, and the determination unit 17 are, for example, a CPU (Central Processing Unit) and an MPU. It is composed of processors such as (Micro Processing Unit) and DSP (Digital Signal Processor), and integrated circuits such as ASIC (Application Specific Integrated Circuit) and FPGA (Field Programmable Gate Array).

Even if the shape line acquisition unit, the registration unit, the plane position identification unit, the projection straight line identification unit, the stereoscopic position estimation unit, and the determination unit in the present invention are configured by a common processor or integrated circuit. It may be configured by individual processors or integrated circuits.

The communication unit 18 is connected to the image storage device 5 via the communication network 4 and receives (acquires) an X-ray fluoroscopic image and a stereoscopic image from the image storage device 5. The communication unit 18 is connected to the display 6 and transmits control information described later and an X-ray fluoroscopic image (aligned with the stereoscopic image) to the display 6. The communication unit 18 is an interface including, for example, a LAN connector, a DVI (Digital Visual Interface) connector, and the like.

● Local coordinate system and arc length parameters Next, the local coordinate system and arc length parameters will be explained.

FIG. 6 is a schematic diagram showing the relationship between the center line C1 and the arc length parameter and the local coordinate system.

The "arc length parameter" is a parameter indicating the distance from the reference point on the center line C1 to a predetermined node, and is calculated by applying differential geometry to the minute line segments constituting the center line C1 and the center line C1. Will be done. That is, the present device 1 can calculate the distance from the reference point to the predetermined node on the center line C1 by calculating the arc length parameter. The "reference point" is a point corresponding to the position of the blood vessel BV into which the guide wire 7 is inserted on the center line C1.

The "local coordinate system" is a coordinate system whose origin is a predetermined node included in the center line C1. The local coordinate system includes a first axis e1, a second axis e2, and a third axis e3. The "first axis e1" is an axis indicating the tangential direction at the node of the center line C1. The "second axis e2" is an axis indicating a direction toward the center of curvature at the node of the center line C1. The "third axis e3" is an axis orthogonal to the first axis e1 and the second axis e2, and is an axis indicating the bending angle (phase) of the center line C1. That is, the coordinate plane including the second axis e2 and the third axis e3 in the local coordinate system is a plane to which the cross section orthogonal to the length direction of the blood vessel BV including the node as the origin belongs. The size of each axis e1-e3 is calculated by applying differential geometry to the center line C1 and the minute line segments constituting the center line C1.

In the figure, the length along the center line C1 from the reference point P1 to the predetermined node P4, that is, the length of the blood vessel BV from the reference point P1 to the node P4 is the arc length parameter S of the node P4. Is shown.

● Image processing method ●
Next, an embodiment of the method executed by the present apparatus 1 will be described.

FIG. 7 is a flowchart showing an embodiment of the present method.

This method includes a position determination process (S1) and a reliability determination process (S2). The apparatus 1 determines the position of the tip portion 71 of the guide wire 7 in the stereoscopic image by the position determination process (S1), and determines the reliability (accuracy) of the determined position by the reliability determination process (S2). do.

● Position determination process First, the present device 1 executes a position determination process (S1) to determine the position of the tip portion 71 of the guide wire 7 in the stereoscopic image.

FIG. 8 is a flowchart of the position determination process (S1).

The present device 1 acquires a stereoscopic image of the blood vessel BV of the subject from the image storage device 5 by using the communication unit 18 (S101). The stereoscopic image of the blood vessel BV is acquired in advance by the stereoscopic image acquisition device 3 and stored in the image storage device 5. The acquired stereoscopic image of the blood vessel BV is stored in the storage unit 11 together with the position information of the stereoscopic image.

Next, the present device 1 acquires the center line C1 of the blood vessel BV by using the shape line acquisition unit 12 (S102). The shape line acquisition unit 12 acquires the center line C1 based on the stereoscopic image of the blood vessel BV, divides the center line C1 into a plurality of minute line segments, and specifies a plurality of nodes connecting the line segments. The center line C1 is stored in the storage unit 11 in association with the position information of the stereoscopic image that is the base of the center line C1 and the information of the line segment / node.

Next, the present device 1 acquires an X-ray fluoroscopic image (hereinafter referred to as “first image”) for aligning the stereoscopic image of the blood vessel BV from the image storage device 5 using the communication unit 18 (S103). ). The first image is stored in the storage unit 11 together with the position information of the first image. At this time, the present device 1 also acquires the position information of each of the X-ray source 21 and the screen 22 when the first image is captured, and stores the same position information in the storage unit 11 in association with the first image.

Next, the present apparatus 1 uses the registration unit 13 to align the stereoscopic image with the first image (S104). As described above, the registration unit 13 aligns the first image with the stereoscopic image by using a known 2D / 3D registration algorithm. The position information of the stereoscopic image aligned with the first image is stored in the storage unit 11.

Next, the present device 1 uses the communication unit 18 to obtain an X-ray fluoroscopic image (hereinafter referred to as “second image”) for identifying the position of the tip end 71 in the X-ray fluoroscopic image from the image storage device 5. Obtained from the image storage device 5 (S105). The second image is captured under the same conditions as the first image, that is, in a state where the positions of the X-ray source 21 and the screen 22 when the first image is captured are maintained. The second image is stored in the storage unit 11. At this time, the present device 1 also acquires the position information of each of the X-ray source 21 and the screen 22 when the second image is captured, and stores the same position information in the storage unit 11 in association with the second image.

The apparatus may use the already acquired first image as the second image.

Next, the present device 1 uses the plane position specifying portion 14 to identify the position of the tip portion 71 moving inside the blood vessel BV in the second image (S106). As described above, the plane position specifying unit 14 specifies the position of the tip portion 71 in the second image by using a known image processing algorithm. The position of the identified tip portion 71 in the second image is stored in the storage unit 11.

The plane position specifying portion may specify the position of the tip portion in the X-ray fluoroscopic image based on the change with time of the X-ray fluoroscopic image. That is, for example, the plane position specifying portion detects the difference between the two X-ray fluoroscopic images captured along the time series, and identifies the position having the same difference as the position of the tip portion.

Next, the present device 1 determines whether or not the tip portion 71 has moved by using the plane position specifying portion 14 (S107).

When the tip portion 71 has not moved (“No” in S107), the apparatus 1 repeats the processes 105-107.

When the tip portion 71 moves (“Yes” in S107), the apparatus 1 identifies the projection straight line C2 by using the projection straight line specifying portion 15 (S108). The projected straight line specifying unit 15 contains the position information of each of the X-ray source 21 and the screen 22 stored in the storage unit 11 in association with the second image, and the inside of the second image of the tip portion 71 specified by the plane position specifying unit 14. Based on the position of, the projection straight line C2 connecting the X-ray source 21 and the tip portion 71 in the second image (that is, the tip portion 71 projected on the screen 22) is specified. The projection straight line specifying unit 15 divides the projection straight line C2 into a plurality of minute line segments, and identifies a plurality of nodes connecting the line segments. The projected straight line C2 is associated with the information of the line segment / node and stored in the storage unit 11.

Next, the present device 1 estimates the position of the tip portion 71 in the stereoscopic image using the stereoscopic position estimation unit 16 (S109). The three-dimensional position estimation unit 16 identifies the node (hereinafter referred to as “shortest point”) k (see FIG. 8) having the shortest distance from the center line C1 among the plurality of nodes included in the projection straight line C2. The shortest point k is a position on the projection straight line C2 where the tip portion 71 is most likely to be present. The stereoscopic position estimation unit 16 estimates the position of the shortest point k as the position of the tip portion 71 in the stereoscopic image. The position information of the specified shortest point k is stored in the storage unit 11.

Next, the present device 1 uses the determination unit 17 to use the node whose distance from the shortest point k is the shortest among the nodes included in the center line C1 (hereinafter referred to as “shortest center point”) i (see FIG. 8). ) Is specified (S110). The position information of the specified shortest center point i is stored in the storage unit 11.

FIG. 9 is a schematic diagram showing the contents of the position estimation process of the tip portion 71 in the stereoscopic image by the stereoscopic position estimation unit 16.
In the figure, the shortest center point i among a plurality of nodes included in the center line C1 is indicated by a white circle, and the shortest point k among a plurality of nodes included in the projection straight line C2 is indicated by a white square.

Return to FIG.
Next, the present device 1 uses the determination unit 17 to specify the cross section of the blood vessel BV at the shortest center point i (S111). As described above, when the center line C1 is acquired by using the shape line acquisition unit 12, the apparatus 1 stores the information of each node and the position information of the stereoscopic image which is the base of the center line C1 in association with each other. Store in part 11. That is, the determination unit 17 can specify the cross section of the blood vessel BV at the shortest center point i by specifying the coordinate plane to which the cross section of the blood vessel BV at the shortest center point i belongs. As described above, the cross section of the blood vessel BV is located on the coordinate plane including the second axis e2 and the third axis e3 of the local coordinate system with the node as the origin. Therefore, the determination unit 17 can specify the cross section of the blood vessel BV at the shortest center point i by specifying the local coordinate system with the shortest center point i as the origin. The information on the cross section of the identified blood vessel BV is associated with the information on the shortest center point i and the local coordinate system, and is stored in the storage unit 11.

Next, the present device 1 uses the determination unit 17 to determine whether or not the shortest point k is included in the cross section of the blood vessel BV at the shortest center point i (S112). When the line segment dividing the center line C1 is sufficiently small, the shortest point k is located on the coordinate plane consisting of the second axis e2 and the third axis e3 in the local coordinate system with the shortest center point i as the origin. .. That is, the position of the shortest point k is expressed using the e2 vector and the e3 vector. In other words, the position of the shortest point k in the cross section in the local coordinate system is from the distance from the shortest center point i in the direction of the second axis e2 to the shortest point k and the shortest center point i in the direction of the third axis e3. Includes the distance to the shortest point k. The determination unit 17 calculates whether or not the shortest point k is included in the cross section of the blood vessel BV at the shortest center point i by calculating the coordinates (polar coordinates) of the shortest point k in the local coordinate system with the shortest center point i as the origin. To judge. The determination result is stored in the storage unit 11.

FIG. 10 is a schematic diagram showing the relationship between the local coordinate system, the cross section of the blood vessel BV, and the shortest point k at the shortest center point i.
In the figure, the alternate long and short dash line indicates the outline of the cross section of the blood vessel BV. In the figure, the cross section of the blood vessel BV is located on the coordinate plane consisting of the second axis e2 and the third axis e3 of the local coordinate system, and the shortest point k is the coordinate plane consisting of the second axis e2 and the third axis e3. Indicates that it is located on top.

Return to FIG.
When the shortest point k is included in the cross section of the blood vessel BV at the shortest center point i (“Yes” in S112), the determination unit 17 determines that the shortest point k is at the position of the tip portion 71 in the stereoscopic image (inside the blood vessel BV). It is determined that there is, and the shortest point k is determined as the position of the tip portion 71 in the stereoscopic image (S113). That is, when the shortest point k is included in the cross section of the blood vessel BV, the shortest point k is the position of the tip portion 71 inside the blood vessel BV at the shortest center point i.

As described above, the shortest point k is located on the coordinate plane including the second axis e2 and the third axis e3 of the local coordinate system with the shortest center point i as the origin, and within the cross section of the blood vessel BV. That is, the shortest point k is arranged alongside the shortest center point i in the cross section of the blood vessel BV centered on the shortest center point i. Therefore, the determination unit 17 advances the arc length parameter from the reference point to the shortest center point i (that is, the distance from the reference point to the shortest center point i on the center line C1), and the tip portion 71 advances inside the blood vessel BV. It is regarded as the distance.

As described above, the determination unit 17 has the position (arc length parameter) on the center line C1 from the reference point of the center line C1 to the shortest center point i and the position in the cross section in the local coordinate system with the shortest center point i as the origin. The position of the shortest point k (e2 vector: radius, e3 vector: angle (phase)) is specified, and the position on the center line C1 and the position of the shortest point k in the local coordinate system are the positions of the tip 71. To be determined as. The position information (arc length parameter, radius, angle) of the shortest point k is stored in the storage unit 11 as information indicating the position of the tip portion 71 in the stereoscopic image.

On the other hand, when the shortest point k is not included in the cross section of the blood vessel BV at the shortest center point i (“No” in S112), the determination unit 17 determines that the shortest point k is not the position in the stereoscopic image of the tip portion 71. (S114).

In this way, the present device 1 estimates the position of the tip portion 71 using the local coordinate system of the center line C1. As described above, the second axis e2 of the local coordinate system is an axis indicating the direction toward the center of curvature of the bending portion of the center line C1 (blood vessel BV), and the third axis e3 is the bending of the center line C1 (blood vessel BV). It is an axis indicating an angle (direction). Therefore, the present device 1 notifies the operator of the second axis e2 and the third axis e3 calculated by the present method to support the operation of the operator's endovascular treatment instrument and the blood vessel shape. It is possible to support the understanding of. Further, in the process of calculating the directions of the second axis e2 and the third axis e3, the present device 1 has the curvature of the center line C1, the radius of curvature (the distance from the shortest center point i to the center of curvature), and the torsion of a curve (second). It is possible to calculate (a value obtained by internally producting the value calculated by differentiating the axis e2 with the third axis e3). Therefore, the present device 1 alerts the operator to the operator by notifying the operator of the curvature, radius of curvature, and torsion of the center line C1, and assists the operator in operating the endovascular treatment instrument. be able to. In this case, the calculated information such as the curvature, the radius of curvature, and the torsion of a curve is associated with the information on the center line C1 and stored in the storage unit 11.

-Reliability determination process Next, the present device 1 executes the reliability determination process (S2) to determine the reliability of the position of the tip portion 71 determined by the position determination process (S1) in the stereoscopic image.

FIG. 11 is a flowchart of the reliability determination process (S2).
FIG. 12 is a schematic diagram showing the relationship between the blood vessel BV and the projected straight line C2 in the reliability determination process (S2).

First, the present device 1 uses the determination unit 17, and among the plurality of nodes included in the projection straight line C2, a plurality of nodes located on the contour line of the cross section of the blood vessel BV at the shortest center point i (two in the present embodiment). ) (Hereinafter referred to as “contour point”) is specified (S201).

The "node located on the contour line of the cross section of the blood vessel BV" is a node located on the contour line or a node closest to the contour line. That is, for example, when there is no node located on the contour line, the determination unit 17 specifies the node closest to the contour line as the contour point.

Next, the present device 1 uses the determination unit 17 to identify the contour point proximal to the X-ray source 21 as the proximal point p among the plurality of contour points, and the contour point distal to the X-ray source 21. Is specified as the distal point q (S202). The position information of each of the identified proximal point p and the distal point q is stored in the storage unit 11.

Next, the present device 1 uses the determination unit 17 to calculate the distance L1 on the projection straight line C2 between the proximal point p and the distal point q (hereinafter referred to as “contour distance”) (S203). The calculated contour distance L1 is stored in the storage unit 11.

Next, the present device 1 uses the determination unit 17 to determine the reliability of the position of the tip portion 71 based on the contour distance L1 (S204).

Here, the shortest point k estimated in the process S109 and determined in the process S113 is a position on the projection straight line C2 where the tip portion 71 is most likely to be present, as described above. On the other hand, between the proximal point p and the distal point q on the projection straight line C2 is a position where the tip portion 71 may exist on the projection straight line C2. That is, as the contour distance L1 becomes longer, the range in which the tip portion 71 may exist becomes wider. In other words, the reliability of the position of the tip portion 71 determined by the determination unit 17 decreases as the contour distance L1 increases, and increases as the contour distance L1 decreases.

The determination of the reliability of the position of the tip portion 71 based on the contour distance L1 is performed by various methods. That is, for example, the determination unit 17 determines the reliability that the shortest point k is the position in the stereoscopic image of the tip portion 71 based on the absolute value of the contour distance L1.

The determination unit in the present invention may compare the absolute value of the contour distance with a predetermined threshold value and determine the reliability of the position of the tip portion based on the magnitude thereof. In this case, the predetermined threshold value is stored in the storage unit in advance. Further, for example, the determination unit may determine the reliability of the position of the tip portion based on the relative ratio of the contour distance to the diameter of the cross section of the blood vessel. Further, for example, the determination unit may determine the reliability of the tip portion based on the number of nodes existing within the contour distance.

Next, the present device 1 stores the calculated contour distance L1 and the determination result of the reliability of the position of the tip portion 71 based on the contour distance L1 in the storage unit 11 in association with the position of the shortest point k (S205). ).

● Example ●
Next, a specific example based on the embodiment of the present apparatus 1 described above will be described by taking numerical analysis when the guide wire model is inserted into the blood vessel model as an example.

In this example, each condition used for the numerical analysis is as follows.
The diameter of the guide wire is 0.3 mm, and the Young's modulus of the guide wire is 20 GPa. Since the blood vessel model is developed on the YZ plane, the center line of the blood vessel model exists on the YZ plane. The X-ray source exists on the X-axis, and its position coordinates are X = 400 mm and Y, Z = 0 mm. That is, X-rays are emitted from the direction perpendicular to the YZ plane on which the blood vessel model is developed. The X-ray irradiation angle at this time is an ideal X-ray irradiation angle. The screen exists on the X axis, and its position coordinates are X = −400 mm and Y, Z = 0 mm. That is, the screen is arranged on the X-axis at a position 800 mm away from the X-ray source.

Here, the relationship between the position on the X-axis of the screen and the fluoroscopic image acquired by the screen is a similar relationship. Therefore, assuming that the position of the screen is a unit distance (1 mm) away from the position of the X-ray source, the position (x, y, z) of the tip of the guide wire in the three-dimensional space and the position projected on the screen. The following relationship of Equation 1 holds between the positions (u, v) of the tip.

(Equation 1)

In Equation 1, λ is an arbitrary constant and P is a 3-by-4 matrix.

Each element of the P-matrix of Equation 1 is calculated by finding the relationship between the three-dimensional position and the position projected on the screen for a point whose three-dimensional position is known.

In this embodiment, it is assumed that the X-ray source exists at X = 400 mm and Y, Z = 0 mm, and the screen exists at X = −400 mm and Y, Z = 0 mm. Therefore, the P-matrix is expressed by the following equation 2.

(Equation 2)

The P-matrix represented by Equation 2 means a transformation that projects a point in three-dimensional space onto a point on the screen. Therefore, a virtual X-ray fluoroscopic image can be obtained based on the three-dimensional position of the tip of the guide wire obtained by the numerical calculation.

In this embodiment, the position of the tip in the three-dimensional space estimated by using this method based on the position of the tip of the guide wire on the virtual X-ray fluoroscopic image (hereinafter referred to as “virtual position”). Is compared with the three-dimensional position of the tip portion determined as the correct answer value, and the error between the virtual position and the correct answer value and the reliability of the virtual position are evaluated. The evaluation results are shown in Table 1.

The angle in the table indicates an angle obtained by rotating the X-ray irradiation angle with the Y-axis and the Z-axis as rotation axes from the ideal X-ray irradiation angle (0 degree). In the table, the radius indicates the second axis e2 in the local coordinate system, and the angle indicates the third axis e3. The reliability index in the table indicates the length of the contour distance L1.

Generally, the diameter of the guide wire is about 0.3 mm, and the operator operates the guide wire in units of about 1 mm. As shown in Table 1, the arc length parameter and radius are estimated with sufficient accuracy at an ideal X-ray irradiation angle (0 degree), and X-rays rotated 50 degrees with respect to one axis. The same applies to the irradiation angle. On the other hand, the angle is estimated with sufficient accuracy at the ideal X-ray irradiation angle, but deviates by about 30 degrees at the X-ray irradiation angle rotated by 50 degrees with respect to one axis. However, a deviation of 30 degrees with respect to 360 degrees is a practically acceptable error. As shown in Table 1, the reliability index increases as the axis of rotation increases from the ideal X-ray irradiation angle. That is, the reliability of the virtual position estimated by this method decreases according to the angle at which the X-ray irradiation angle deviates from the ideal X-ray irradiation angle.

● Summary According to the embodiment described above, the present device 1 regards the blood vessel BV as a curve (center line C1) in the three-dimensional space, and positions the tip portion 71 in the blood vessel BV with the center line C1 and a projected straight line. By substituting the geometric relationship with C2, the position of the tip portion 71 in the stereoscopic image is estimated. In other words, the present device 1 sets two points (shortest point k, shortest center point i) that are the minimum distance between the curve (center line C1) and the straight line (projection straight line C2) existing in the three-dimensional space. By determining, the position of the tip portion 71 in the stereoscopic image is estimated. As a result, the present device 1 is used for calculating the estimation of the position of the endovascular treatment device (tip portion 71 of the guide wire 7) in the blood vessel BV, as compared with the conventional technique of grasping the blood vessel as a model having a three-dimensional shape. It is possible to reduce the processing load.

Further, according to the embodiment described above, the present device 1 determines the reliability that the shortest point k is the position in the stereoscopic image of the tip portion 71 based on the contour distance L1. That is, the present device 1 can reduce the processing load required for calculating the estimation of the position of the endovascular treatment instrument (tip portion 71 of the guide wire 7) in the blood vessel BV, and can determine the reliability of the estimation result. ..

Further, according to the embodiment described above, the present apparatus 1 identifies the second axis e2 and the third axis e3 of the local coordinate system in the process of estimating the position of the tip portion 71 in the stereoscopic image. Therefore, the present device 1 notifies the operator of the second axis e2 and the third axis e3 to support the operation of the operator's endovascular treatment instrument (for example, navigation) and to support the operation of the blood vessel shape. It is possible to support grasping.

Furthermore, the present device 1 calculates the curvature, radius of curvature (distance from the shortest center point i to the center of curvature), and torsion of a curve of the center line C1 in the process of calculating the directions of the second axis e2 and the third axis e3. can do. Therefore, the present device 1 alerts the operator to the operator by notifying the operator of the curvature, radius of curvature, and torsion of the center line C1, and assists the operator in operating the endovascular treatment instrument. be able to.

In the embodiment described above, the method executed by the apparatus 1 includes the reliability determination process (S2). Instead, the apparatus does not have to execute the reliability determination process.

Further, the present device may generate control information for controlling the operation of the external device by using the determination unit. That is, for example, the determination unit sends notification information to the display based on the distance (radius of curvature) from the same node to the center of curvature in the direction of the second axis of the local coordinate system with the predetermined node of the center line as the origin. Generate control information to be displayed. The notification information is, for example, information for notifying the operator of a portion of the blood vessel having a small curvature (that is, a portion where the blood vessel bends at a steep angle). The present device uses the communication unit to transmit the control information to the display and display the notification information on the display. By checking the broadcast information displayed on the display, the surgeon reduces the speed of movement of the endovascular treatment device in the blood vessel, for example, so as not to damage the blood vessel.

Further, the determination unit displays control information on the display based on the change over time in the distance from the shortest center point to the center of curvature in the direction of the second axis of the local coordinate system with the shortest center point as the origin. May be generated. In other words, the determination unit may generate control information according to the degree of curvature of the blood vessel at the current position of the endovascular treatment instrument. In this case, the broadcast information is, for example, information that calls attention to the operator regarding the operation of the endovascular treatment instrument. For example, the determination unit generates control information when the curvature of the blood vessel is equal to or less than a predetermined threshold value, and does not generate control information when the curvature of the blood vessel is larger than the predetermined threshold value. As a result, the present device can display the notification information on the display only when the curvature of the blood vessel is equal to or less than a predetermined threshold value, and alert the operator to the operation of the endovascular treatment instrument. The predetermined threshold value is stored in the storage unit in advance.

FIG. 13 is a schematic diagram showing an example of the display of the display controlled by the present device.
The figure shows that the curvature of the blood vessel is larger than a predetermined threshold value, and control information is not transmitted from the present device to the display.

FIG. 14 is a schematic diagram showing another example of the display of the display controlled by the present device.
In the figure, the curvature of the blood vessel is equal to or less than a predetermined threshold value, control information is transmitted from the device to the display, and "!" Is displayed as information to call the operator's attention to the operation of the endovascular treatment device. Show that it is.

Furthermore, the determination unit may generate control information based on the torsional curve of the center line and the change over time of the torsional curve calculated in the local coordinate system with the shortest center point as the origin. In other words, the determination unit may generate control information according to the degree of torsion of the blood vessel (shortest center point) at the current position (shortest point) of the endovascular treatment device. In this case, the present device can alert the operator to the operation of the endovascular treatment instrument according to the degree of torsion of the blood vessel, as in the case of utilizing the curvature of the blood vessel described above.

Furthermore, the device may be connected to a moving device (eg, a surgical robot) that moves the endovascular treatment device inside the blood vessel to generate control information that changes the moving action of the moving device. The mobile device is an example of an external device in the present invention. That is, for example, the determination unit generates control information for lowering the speed (movement speed) at which the moving device moves the endovascular treatment device when the curvature of the blood vessel is equal to or less than a predetermined threshold value, and the curvature of the blood vessel is larger than the predetermined threshold value. When the movement speed is returned (increased), control information is generated. As a result, the moving device can slowly move the endovascular treatment device in a part where the endovascular treatment device needs to be carefully moved, such as a portion where the blood vessel bends at a steep angle. The predetermined threshold value is stored in the storage unit in advance.

Furthermore, the shape line acquisition unit may acquire the position information of the center line of the blood vessel specified by the external device via the communication network.

● Summary of image processing equipment according to this embodiment ●
The features of the image processing apparatus according to the present embodiment described above are summarized below.

(Feature 1)
The position information of the plan image (X-ray fluoroscopic image) of the tube body formed by the radiation (X-ray) emitted from the radiation source (X-ray source 21) passing through the tube body (blood vessel BV), and
The position information of the stereoscopic image of the tube and
And the storage unit (storage unit 11) in which
A shape line acquisition unit (shape line acquisition unit 12) that acquires a shape line (center line C1) indicating the shape of the tube body based on the stereoscopic image,
A registration unit (registration unit 13) that aligns the plane image and the stereoscopic image based on the position information of the plane image and the position information of the stereoscopic image.
A plane position specifying portion (planar position specifying portion 14) that specifies a position in the plane image of a moving body (tip portion 71 of the guide wire 7) that moves inside the tube body,
A projection straight line specifying unit (projection straight line specifying unit 15) that specifies a projection straight line (projection straight line C2) connecting the radiation source and the moving body whose position in the plane image is specified.
Of the plurality of points (nodes) included in the projected straight line, the position of the shortest point (shortest point k) having the shortest distance from the shape line is estimated as the position of the moving body in the stereoscopic image. The position estimation unit (stereoscopic position estimation unit 16) and
Have
An image processing device (this device 1).

(Feature 2)
A determination unit (determination unit 17) that determines that the shortest point is the position of the moving object in the stereoscopic image.
Equipped with
The determination unit
Among the plurality of points included in the shape line, the shortest center point (shortest center point i) having the shortest distance from the shortest point is specified.
Identify the cross section of the tube at the shortest center point and
It is determined whether or not the shortest point is included in the cross section, and the result is determined.
When the shortest point is included in the cross section, the shortest point is determined as the position of the moving body in the stereoscopic image.
The image processing apparatus according to feature 1.

(Feature 3)
The determination unit
Among the plurality of points included in the projected straight line, a plurality of contour points located on the contour line of the cross section are identified.
Of the plurality of contour points, the contour point proximal to the radiation source is specified as the proximal point (proximal point p).
Of the plurality of contour points, the contour point distal to the radiation source is specified as a distal point (distal point q).
The contour distance (contour distance L1) on the projected straight line between the proximal point and the distal point is calculated.
Based on the contour distance, the reliability that the shortest point is the position of the moving object in the stereoscopic image is determined.
The image processing apparatus according to feature 2.

(Feature 4)
The determination unit
The position on the shape line from the reference point of the shape line to the shortest center point,
The position of the shortest point in the cross section in the local coordinate system with the shortest center point as the origin, and
Identify and
The position on the shape line and the position of the shortest point in the cross section in the local coordinate system are determined as the positions of the moving body.
The image processing apparatus according to feature 2.

(Feature 5)
The local coordinate system is
The first axis (first axis e1) indicating the tangential direction at the shortest center point of the shape line,
A second axis (second axis e2) indicating a direction toward the center of curvature at the shortest center point of the shape line, and
A third axis (third axis e3) orthogonal to the first axis and the second axis, and
including,
The image processing apparatus according to feature 4.

(Feature 6)
The position of the shortest point in the cross section in the local coordinate system is
The distance from the shortest center point to the shortest point in the direction of the second axis,
The distance from the shortest center point to the shortest point in the direction of the third axis,
including,
The image processing apparatus according to feature 5.

(Feature 7)
Connect to an external device (display 6, mobile device),
The determination unit operates the external device based on at least one of the distance from the shortest center point to the curvature center point in the direction of the second axis or the torsion at the shortest center point. Generate control information to control
The image processing apparatus according to feature 6.

(Feature 8)
The control information is generated based on at least the time course of either the distance from the shortest center point to the curvature center point in the direction of the second axis or the torsion at the shortest center point. ,
The image processing apparatus according to feature 7.

(Feature 9)
The external device is a display on which the planar image aligned with the stereoscopic image is displayed.
The control information is information for displaying the broadcast information on the display.
The image processing apparatus according to feature 7.

(Feature 10)
The external device is a moving device that moves the moving body inside the tube body.
The control information is information that causes the moving device to change the moving operation of the moving body.
The image processing apparatus according to feature 7.

(Feature 11)
The plane position specifying portion identifies the position of the moving body in the plane image based on the change with time of the plane image.
The image processing apparatus according to feature 1.

(Feature 12)
The projection straight line specifying unit identifies the projection straight line based on the position information of the radiation source and the position information of the moving body whose position in the plane image is specified.
The image processing apparatus according to feature 1.

(Feature 13)
The registration unit is
Based on the position information of the plane image, the position information of the contour line of the tube body is extracted.
Aligning the plane image and the stereoscopic image based on the position information of the contour line.
The image processing apparatus according to feature 1.

(Feature 14)
The radiation is an X-ray and
The tube is a blood vessel and
The shape line is the center line of the tube body.
The image processing apparatus according to feature 1.

(Feature 15)
The plane position specifying portion identifies a part of the moving body as a position in the plane image of the moving body.
The image processing apparatus according to feature 1.

1 Image processing device 11 Storage unit 12 Shape line acquisition unit 13 Registration unit 14 Plane position identification unit 15 Projection straight line identification unit 16 Solid position estimation unit 17 Judgment unit 18 Communication unit 2 X-ray irradiation device 21 X-ray source (radioactive source)
22 Screen 3 Stereoscopic image acquisition device 4 Communication network 5 Image storage device 6 Display (external device)
7 Guide wire 71 Tip BV Blood vessel C1 Center line C2 Projection straight line i Shortest center point k Shortest point p Proximal point q Distal point

Claims (16)

The position information of the planar image of the tube formed by the radiation emitted from the radiation source passing through the tube, and
The position information of the stereoscopic image of the tube and
And the storage part where
A shape line acquisition unit that acquires a shape line indicating the shape of the tube based on the stereoscopic image, and a shape line acquisition unit.
A registration unit that aligns the planar image and the stereoscopic image based on the positional information of the planar image and the positional information of the stereoscopic image.
A plane position specifying portion that specifies the position of a moving body that moves inside the tube body in the plane image, and a plane position specifying portion.
A projection straight line specifying part that specifies a projection straight line connecting the radiation source and the moving body whose position in the plane image is specified, and a projection straight line specifying portion.
A stereoscopic position estimation unit that estimates the position of the shortest point having the shortest distance from the shape line among the plurality of points included in the projection straight line as the position of the moving object in the stereoscopic image.
A determination unit that determines that the shortest point is the position of the moving object in the stereoscopic image, and
Have
An image processing device characterized by this. The determination unit
Among the plurality of points included in the shape line, the shortest center point having the shortest distance from the shortest point is specified.
Identify the cross section of the tube at the shortest center point and
It is determined whether or not the shortest point is included in the cross section, and the result is determined.
When the shortest point is included in the cross section, the shortest point is determined as the position of the moving body in the stereoscopic image.
The image processing apparatus according to claim 1. The determination unit
Among the plurality of points included in the projected straight line, a plurality of contour points located on the contour line of the cross section are identified.
Of the plurality of contour points, the contour point proximal to the radiation source is specified as the proximal point.
Of the plurality of contour points, the contour point distal to the radiation source is specified as the distal point.
The contour distance on the projected straight line between the proximal point and the distal point is calculated.
Based on the contour distance, the reliability that the shortest point is the position of the moving object in the stereoscopic image is determined.
The image processing apparatus according to claim 2. The determination unit
The position on the shape line from the reference point of the shape line to the shortest center point,
The position of the shortest point in the cross section in the local coordinate system with the shortest center point as the origin, and
Identify and
The position of the moving body is determined based on the position on the shape line and the position of the shortest point in the cross section in the local coordinate system.
The image processing apparatus according to claim 2. The local coordinate system is
The first axis indicating the tangential direction at the shortest center point of the shape line, and
A second axis indicating the direction of the shape line toward the center of curvature at the shortest center point,
A third axis orthogonal to the first axis and the second axis,
including,
The image processing apparatus according to claim 4. The position of the shortest point in the cross section in the local coordinate system is
The distance from the shortest center point to the shortest point in the direction of the second axis,
The distance from the shortest center point to the shortest point in the direction of the third axis,
including,
The image processing apparatus according to claim 5. Connect with an external device
The determination unit operates the external device based on at least one of the distance from the shortest center point to the curvature center point in the direction of the second axis or the torsion at the shortest center point. Generate control information to control
The image processing apparatus according to claim 6. The control information is generated based on at least the time course of either the distance from the shortest center point to the curvature center point in the direction of the second axis or the torsion at the shortest center point. ,
The image processing apparatus according to claim 7. The external device is a display on which the planar image aligned with the stereoscopic image is displayed.
The control information is information for displaying the broadcast information on the display.
The image processing apparatus according to claim 7. The external device is a moving device that moves the moving body inside the tube body.
The control information is information that causes the moving device to change the moving operation of the moving body.
The image processing apparatus according to claim 7. The plane position specifying portion identifies the position of the moving body in the plane image based on the change with time of the plane image.
The image processing apparatus according to claim 1. The projection straight line specifying unit identifies the projection straight line based on the position information of the radiation source and the position information of the moving body whose position in the plane image is specified.
The image processing apparatus according to claim 1. The radiation is an X-ray and
The tube is a blood vessel and
The shape line is the center line of the tube body.
The image processing apparatus according to claim 1. The plane position specifying portion identifies a part of the moving body as a position in the plane image of the moving body.
The image processing apparatus according to claim 1. The computer functions as the image processing device according to any one of claims 1 to 14 .
An image processing program characterized by this. The position information of the planar image of the tube formed by the radiation emitted from the radiation source passing through the tube, and
The position information of the stereoscopic image of the tube and
Is stored in the memory
It is a method of operating an image processing device provided with
The image processing device
A step of aligning the plane image and the stereoscopic image based on the position information of the plane image and the position information of the stereoscopic image.
A step of specifying a shape line indicating the shape of the tube body based on the stereoscopic image aligned with the plane image, and a step of specifying the shape line.
A step of identifying the position of the moving body moving inside the tube body in the plane image, and
A step of specifying a projection straight line connecting the radiation source and the moving body whose position in the plane image is specified.
A step of estimating the position of the shortest point having the shortest distance from the shape line among the plurality of points included in the projection straight line as the position of the moving body in the stereoscopic image.
A determination step for determining that the shortest point is the position of the moving object in the stereoscopic image, and
Have
A method of operating an image processing device , characterized in that.

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