Method and device for identifying a bifurcation position of a blood vessel, medical imaging apparatus and medium

Abstract

The present application relates to the technical field of position recognition, and discloses a kind of recognition method, device, medical imaging equipment and medium of vascular bifurcation position.First, the tissue image containing including first blood vessel segment and second blood vessel segment vascular tree is acquired.Then, based on the blood vessel center line of vascular tree, the bifurcation starting position of first blood vessel segment and second blood vessel segment is acquired.Finally, based on the blood vessel center line of tissue image and vascular tree, the bifurcation end position of first blood vessel segment and second blood vessel segment is acquired.The above-mentioned embodiment utilizes both blood vessel center line information and tissue information containing vascular tree, can accurately determine the starting position and end position of vascular bifurcation, to improve the quality of bifurcation image.Determine the starting position and end position of vascular bifurcation, more convenient for blood vessel analysis, provide reliable basis for diagnosis and treatment.

Description

Technical Field

[0001] This invention relates to the field of location recognition technology, and in particular to a method, device, medical imaging equipment, and medium for identifying the location of blood vessel bifurcation. Background Technology

[0002] Blood flow tends to become turbulent at vascular bifurcation points, causing significant impact on the local vessel walls and increasing the risk of atherosclerotic lipid deposition at these locations. This leads to plaque formation and ultimately, arterial stenosis. Therefore, a method for identifying vascular bifurcation points is needed. Summary of the Invention

[0003] The embodiments described in this specification aim to at least partially solve one of the technical problems in the related art. To this end, the embodiments of this specification propose a method, apparatus, medical imaging device, and medium for identifying the location of blood vessel bifurcation.

[0004] This specification provides a method for identifying the location of blood vessel bifurcation, the method comprising:

[0005] Acquire a tissue image containing a vascular tree, the vascular tree including a first vascular segment and a second vascular segment;

[0006] Based on the vascular centerline of the vascular tree, the bifurcation start positions of the first vascular segment and the second vascular segment are obtained;

[0007] Based on the tissue image and the vascular centerline of the vascular tree, the bifurcation ends of the first and second vascular segments are obtained.

[0008] In one embodiment, obtaining the bifurcation start position of the first blood vessel segment and the second blood vessel segment includes:

[0009] Based on the blood vessel centerline, preliminary location data of the blood vessel bifurcation point are determined;

[0010] Using the preliminary location data as a traversal reference point, the minimum value of the distance between the first blood vessel segment and the second blood vessel segment is calculated to obtain the bifurcation starting position.

[0011] In one embodiment, the vascular centerline includes a first vascular centerline of the first vascular segment and a second vascular centerline of the second vascular segment; the preliminary location data for determining the vascular bifurcation includes:

[0012] Multiple main sampling points on the centerline of the first blood vessel and multiple designated branch sampling points on the centerline of the second blood vessel are determined; wherein, the multiple designated branch sampling points are a portion of the multiple branch sampling points on the centerline of the second blood vessel.

[0013] Along the blood flow direction, the distance between the main trunk sampling point and the nearest branch sampling point is sequentially obtained. Based on the positions of the first branch sampling point with a distance greater than a first distance threshold and the corresponding main trunk sampling point, the preliminary position data is determined. The first distance threshold is determined by the maximum preset distance between the center line of the first blood vessel and the center line of the second blood vessel.

[0014] In one embodiment, the vascular centerline includes a first vascular centerline of the first vascular segment and a second vascular centerline of the second vascular segment; the step of using the preliminary position data as a traversal reference point to calculate the minimum value of the distance between the first vascular segment and the second vascular segment to obtain the bifurcation starting position includes:

[0015] Along the opposite direction of blood flow, starting from the preliminary position data, the distance between the main sampling point of the first blood vessel centerline and the branch sampling point of the second blood vessel centerline is traversed to obtain the minimum distance value;

[0016] The bifurcation starting position is obtained based on the branch sampling point and the main trunk sampling point corresponding to the first minimum distance value that is less than the third distance threshold; wherein, the third distance threshold is determined by the minimum preset distance between the center line of the first blood vessel and the center line of the second blood vessel.

[0017] In one embodiment, the step of obtaining the bifurcation end position of the first and second vascular segments is as follows:

[0018] Using the bifurcation start position as a reference point, multiple orthogonal visual planes are determined along the first vessel centerline of the first vessel segment, and the orthogonal visual planes are perpendicular to the first vessel centerline.

[0019] Based on the tissue images, separation evaluation data of the first and second vascular segments are obtained on each of the orthogonal planes of the field of view;

[0020] The position corresponding to the orthogonal plane of the field of view that satisfies the separation evaluation threshold is determined as the bifurcation end position.

[0021] In one embodiment, acquiring separation assessment data of the first and second vascular segments on each orthogonal plane of the field of view based on the tissue image includes:

[0022] Determine the first intersection point of the first vessel centerline of the first vessel segment with a designated field of view, and the second intersection point of the second vessel centerline of the second vessel segment with the designated field of view; wherein, the designated field of view is the orthogonal field of view corresponding to the separation evaluation data to be solved;

[0023] Based on the tissue image, determine the specified pixel data corresponding to the line connecting the first intersection point and the second intersection point, the pixel data at the first intersection point, and the pixel data at the second intersection point;

[0024] The separation evaluation data is determined based on the degree of difference between the specified pixel data and the pixel data at the first intersection point and the pixel data at the second intersection point; or, the separation evaluation data is determined based on the degree of difference between the specified pixel data and the pixel data at the first intersection point and the pixel data at the second intersection point, as well as the distance between the first intersection point and the second intersection point.

[0025] In one embodiment, the specified pixel data is the minimum grayscale or CT value of the pixels traversed by the line connecting the first intersection point and the second intersection point.

[0026] In one implementation, the second intersection point is determined in the following manner:

[0027] Determine adjacent first and second sampling points on the center line of the second blood vessel segment in the second blood vessel segment;

[0028] If the first sampling point and the second sampling point are located on different sides of the specified field of view based on the position data of the first sampling point, the position data of the second sampling point, and the normal vector of the specified field of view, the intersection of the line segment between the first sampling point and the second sampling point and the specified field of view is taken as the second intersection point.

[0029] In one embodiment, the method further includes:

[0030] Along the direction of blood flow, determine the starting and ending sampling points on the center line of multiple undetermined second vascular segments;

[0031] For any of the undetermined second blood vessel segments, determine the initial closest distance between the starting sampling point and the center line of the first blood vessel segment, and the final closest distance between the ending sampling point and the end of the first blood vessel segment;

[0032] The undetermined second vascular segment whose starting nearest distance is less than the fourth distance threshold and whose ending nearest distance is greater than the fourth distance threshold is determined as a branch vascular segment that originates from the first vascular segment.

[0033] This specification provides a device for identifying the location of blood vessel bifurcation, the device comprising:

[0034] An acquisition module is used to acquire a tissue image containing a vascular tree, wherein the vascular tree includes a first vascular segment and a second vascular segment;

[0035] The bifurcation start position determination module is used to obtain the bifurcation start positions of the first blood vessel segment and the second blood vessel segment based on the blood vessel centerline of the blood vessel tree.

[0036] The bifurcation end position determination module is used to obtain the bifurcation end positions of the first blood vessel segment and the second blood vessel segment based on the tissue image and the blood vessel centerline of the blood vessel tree.

[0037] This specification provides a medical imaging device, which includes: a memory, and one or more processors communicatively connected to the memory; the memory stores instructions executable by the one or more processors, which, when executed by the one or more processors, cause the one or more processors to perform the steps of the method described in any of the above embodiments.

[0038] This specification provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in any of the above embodiments.

[0039] This specification provides a computer program product that includes instructions that, when executed by a processor of a computer device, enable the computer device to perform the steps of the method described in any of the above embodiments.

[0040] In the above-described embodiment, firstly, a tissue image containing a vascular tree including a first vascular segment and a second vascular segment is acquired. Then, based on the vascular centerline of the vascular tree, the bifurcation start positions of the first and second vascular segments are obtained. Finally, based on the tissue image and the vascular centerline of the vascular tree, the bifurcation end positions of the first and second vascular segments are obtained. This embodiment utilizes both vascular centerline information and tissue information containing the vascular tree, enabling precise determination of the start and end positions of vascular bifurcation, thereby improving the image quality at the bifurcation points. Determining the start and end positions of vascular bifurcation facilitates vascular analysis, providing a reliable basis for diagnosis and treatment. Attached Figure Description

[0041] Figure 1a A flowchart of a method for identifying the location of blood vessel bifurcation provided in the embodiments of this specification;

[0042] Figure 1b A flowchart illustrating the method for identifying the location of blood vessel bifurcation provided in the embodiments of this specification;

[0043] Figure 1c A schematic diagram showing the starting and ending positions of the fork in the embodiment of this specification;

[0044] Figure 2 A flowchart illustrating the method for identifying the location of blood vessel bifurcation provided in the embodiments of this specification;

[0045] Figure 3a A flowchart illustrating the preliminary location data for determining the bifurcation of a blood vessel, provided for the embodiments of this specification;

[0046] Figure 3b A flowchart illustrating the preliminary location data for determining the bifurcation of a blood vessel, provided for the embodiments of this specification;

[0047] Figure 4a A flowchart illustrating the determination of preliminary location data provided for embodiments of this specification;

[0048] Figure 4b A schematic diagram illustrating the determination of a specified branch sampling point and a first preset distance range for the purposes of this specification;

[0049] Figure 4c A schematic diagram illustrating the determination of preliminary location data provided for embodiments of this specification;

[0050] Figure 5a A flowchart illustrating the determination of the fork start position provided for the implementation of this specification;

[0051] Figure 5b A schematic diagram illustrating the determination of the bifurcation start position for embodiments of this specification;

[0052] Figure 6a A flowchart illustrating the process of determining separation evaluation data provided in this specification for implementation methods;

[0053] Figure 6b A schematic diagram illustrating the determination of the orthogonal plane of the field of view for the purposes of this specification;

[0054] Figure 6c A schematic diagram illustrating the determination of separation evaluation data provided for the implementation of this specification;

[0055] Figure 7 A flowchart illustrating the determination of the bifurcation end position provided for the implementation of this specification;

[0056] Figure 8a A flowchart illustrating the determination of the second intersection point provided for embodiments of this specification;

[0057] Figure 8b A schematic diagram for determining the second intersection point provided for the implementation of this specification;

[0058] Figure 9A flowchart illustrating the process for determining whether a non-main coronary artery segment originates from a main coronary artery segment, provided for the implementation of this specification.

[0059] Figure 10a A schematic diagram provided for the implementation of this specification to determine that a non-main coronary artery segment does not originate from a main coronary artery segment;

[0060] Figure 10b A schematic diagram provided for the implementation of this specification to determine that a non-main coronary artery segment does not originate from a main coronary artery segment;

[0061] Figure 10c A schematic diagram provided for the implementation of this specification to determine that a non-main coronary artery segment does not originate from a main coronary artery segment;

[0062] Figure 10d A schematic diagram provided for the implementation of this specification to determine that a non-main coronary artery segment does not originate from a main coronary artery segment;

[0063] Figure 10e A schematic diagram provided for the implementation of this specification to determine that a non-main coronary artery segment originates from a main coronary artery segment;

[0064] Figure 11 A flowchart illustrating the method for identifying the location of blood vessel bifurcation provided in the embodiments of this specification;

[0065] Figure 12 A schematic diagram of a blood vessel bifurcation location identification device provided for embodiments of this specification;

[0066] Figure 13 A schematic diagram of a blood vessel bifurcation location identification device provided for embodiments of this specification. Detailed Implementation

[0067] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0068] Taking the coronary artery as an example, the blood flow in the coronary artery is prone to turbulence at the branching points, which can cause a greater impact on the local blood vessel wall, increasing the risk of atherosclerotic lipids depositing at the bifurcation point, leading to the formation of atherosclerotic plaques and thus causing coronary artery stenosis.

[0069] Because the coronary arteries have many branches, special handling is required for bifurcation locations when using coronary CT technology for coronary vascular analysis and repair of coronary artery motion artifacts. Specifically, bifurcation locations need to be marked within the entire coronary tree for further processing and analysis. Therefore, a method for identifying vascular bifurcation locations is needed.

[0070] Based on this, this specification provides a method for identifying the location of blood vessel bifurcation. First, a tissue image containing a vascular tree including a first vascular segment and a second vascular segment is acquired. Then, based on the vascular centerline of the vascular tree, the bifurcation start positions of the first and second vascular segments are obtained. Finally, based on the tissue image and the vascular centerline of the vascular tree, the bifurcation end positions of the first and second vascular segments are obtained. This embodiment utilizes both vascular centerline information and tissue information containing the vascular tree, enabling precise determination of the start and end positions of blood vessel bifurcation, thereby improving the image quality at the bifurcation point. Determining the start and end positions of blood vessel bifurcation facilitates vascular analysis, providing a reliable basis for diagnosis and treatment.

[0071] This specification provides an example scenario for identifying the location of a blood vessel bifurcation. A blood vessel tree is generated based on a known image, and the location data of each sampling point on the blood vessel tree, along with the first blood vessel segment and its marker, are recorded. Please refer to... Figure 1a First, the bifurcation position of the second vessel segment on the first vessel segment is analyzed. The validity of the second vessel segment is determined based on the beginning-end relationship to identify abnormal branches. If valid, a piecewise approximation method is used to coarsely locate the bifurcation position. Then, a piecewise approximation method is used to accurately calculate the bifurcation start position. Finally, starting from the initial bifurcation position, the bifurcation end position is accurately calculated by combining the vascular features on the orthogonal plane image corresponding to each sampling point.

[0072] For example, taking the coronary artery tree as an example, the coronary artery tree is first generated based on the known image. The first segment of the coronary artery tree can be the right coronary artery Trunk_RCA, the left anterior descending artery Trunk_LAD, and the left circumflex artery Trunk_LCX. The second segment can be the right coronary artery branch Branch_RCA, the left anterior descending artery branch Branch_LAD, and the left circumflex artery branch Branch_LCX.

[0073] Based on the coronary tree, determine the centerlines corresponding to the right coronary artery Trunk_RCA, the left anterior descending artery Trunk_LAD, the left circumflex artery Trunk_LCX, the right coronary artery branch Branch_RCA, the left anterior descending artery branch Branch_LAD, and the left circumflex artery branch Branch_LCX.

[0074] Taking the right coronary artery trunk_RCA and its branch_RCA_1 as examples: Along the blood flow direction, determine the starting and ending sampling points on the centerline corresponding to branch_RCA_1. Determine the initial closest distance between the starting sampling point and the right coronary artery trunk_RCA, and the final closest distance between the ending sampling point and the right coronary artery trunk_RCA. If the initial closest distance is less than a fourth distance threshold, and the final closest distance is greater than the fourth distance threshold, then branch_RCA_1 is determined to be an abnormal branch, and branch_RCA_1 is a branch vessel segment originating from the right coronary artery trunk_RCA.

[0075] Based on the sampling point location data on the centerline corresponding to the right coronary artery branch Branch_RCA_1 and the specified traversal step size 5, a designated branch sampling point is determined on the centerline corresponding to the right coronary artery branch Branch_RCA_1. Based on the location data of the designated branch sampling point and the sampling point location data on the centerline corresponding to the right coronary artery trunk_RCA, at least one trunk sample located within a first preset distance range is determined on the centerline corresponding to the right coronary artery trunk_RCA.

[0076] Determine the minimum distance between a specified branch sampling point and at least one main branch sampling point within a first preset distance range. Perform preliminary location analysis on the specified branch sampling points and main branch sampling points corresponding to the minimum distances greater than the first distance threshold to obtain preliminary location data.

[0077] Along the reverse direction of blood flow, starting from the initial location data, the distance between the right coronary artery Trunk_RCA and its branch Branch_RCA_1 is traversed to obtain the minimum distance value. Based on the branch sampling points and trunk sampling points corresponding to the minimum distance values ​​less than the third distance threshold, the bifurcation starting position is obtained.

[0078] Multiple orthogonal view planes orthogonal to the centerline corresponding to the right coronary artery Trunk_RCA are identified, and these orthogonal view planes are sequentially designated as the specified view planes along the direction. The first intersection point between the centerline corresponding to the right coronary artery Trunk_RCA and the specified view plane, and the second intersection point between the centerline corresponding to the right coronary artery branch Branch_RCA_1 and the specified view plane are determined. Based on the degree of difference between the specified pixel data corresponding to the line connecting the first and second intersection points and the pixel data at the first and second intersection points, as well as the distance between the first and second intersection points, separation evaluation data corresponding to the specified view plane is obtained. The first intersection point corresponding to separation evaluation data below the separation evaluation threshold is determined as the bifurcation end position.

[0079] This specification provides a method for identifying the location of blood vessel bifurcation. Please refer to [link to relevant documentation]. Figure 1b The method for identifying the bifurcation location of the blood vessel may include the following steps:

[0080] S110. Obtain a tissue image containing a vascular tree, wherein the vascular tree includes a first vascular segment and a second vascular segment.

[0081] S120. Based on the vascular centerline of the vascular tree, obtain the bifurcation start position of the first and second vascular segments.

[0082] S130. Based on the tissue image and the vascular centerline of the vascular tree, obtain the bifurcation end position of the first and second vascular segments.

[0083] The vascular tree can be a three-dimensional structural model representing the branching structure of the vascular system. The first vascular segment can be a segment in the vascular tree that has branching vessels. The second vascular segment can be a branching vessel segment that branches off from the first segment relative to it. The bifurcation start point can be the location along the blood flow direction where the second vascular segment first branches off from the first segment. The bifurcation end point can be the location along the blood flow direction where the second vascular segment ends branching off from the first segment. Due to image resolution limitations, the bifurcation end point may be located at the actual bifurcation end point, or it may be downstream of, and adjacent to, the actual bifurcation end point along the blood flow direction. The actual bifurcation end point can be understood as the bifurcation end point of the physical blood vessel. The vascular centerline can be a dashed line, with the solid line position representing the sampling position. The vascular centerline can be located at the center of the vascular cross-section. Due to image resolution limitations, the clarity of the vascular cross-section contour is difficult to guarantee accurately; therefore, the vascular centerline can also be located outside the center of the vascular cross-section, but within the contour of the vessel. The vascular centerline represents the trend of the vascular extension direction.

[0084] Specifically, tissue images requiring vascular bifurcation location identification are acquired based on actual needs. Image processing techniques are used to identify and process the tissue images, obtaining the vascular tree within them. Image processing algorithms and manual labeling are combined to analyze and label the vascular tree in the tissue images, identifying and distinguishing the first and second vascular segments. Image processing algorithms (such as pixel-based analysis or mathematical morphology operations) are used to calculate and identify the vascular tree, determining the vascular centerline of each vessel. Analysis of the vascular centerline determines the bifurcation start point as the location where the first vascular segment begins to branch off into the second vascular segment. Further analysis of the vascular centerline, based on its relationship with the tissue image, determines the bifurcation end point as the location where the first vascular segment ends and branches off into the second vascular segment.

[0085] In some implementations, multiple sampling points are determined on the vascular tree at certain intervals and according to certain rules to represent the morphology of the vascular tree. Using the selected sampling point data, the vascular centerline of the vascular tree can be constructed by interpolation algorithms (such as linear interpolation, spline interpolation), curve fitting (such as polynomial fitting, Bézier curve fitting), and other methods.

[0086] For example, please refer to Figure 1c , Figure 1c 102 in the text refers to the first vascular segment. Figure 1c 104 in the diagram represents the second vascular segment. Please continue reading. Figure 1c The bifurcation start point is the location where the first vascular segment begins to branch into the second vascular segment. The bifurcation end point is the location where the first vascular segment ends and branches into the second vascular segment.

[0087] In the above implementation, firstly, a tissue image containing a vascular tree including a first vascular segment and a second vascular segment is acquired. Then, based on the vascular centerline of the vascular tree, the bifurcation start positions of the first and second vascular segments are obtained. Finally, based on the tissue image and the vascular centerline of the vascular tree, the bifurcation end positions of the first and second vascular segments are obtained. This implementation utilizes both vascular centerline information and tissue information containing the vascular tree, enabling precise determination of the start and end positions of vascular bifurcation, thereby improving the image quality at the bifurcation points. Determining the start and end positions of vascular bifurcation facilitates vascular analysis, providing a reliable basis for diagnosis and treatment.

[0088] This specification also provides a method for identifying the location of a blood vessel bifurcation, wherein the first vessel segment can be a main vessel segment, and the second vessel segment can be a branch vessel segment. Please refer to... Figure 2 The method for identifying the bifurcation location of the blood vessel may include the following steps:

[0089] S210. Determine the preliminary location data of the bifurcation point of the blood vessel.

[0090] S220. Using the preliminary location data as a reference point, calculate the minimum distance between the main vessel segment and the branch vessel segment to obtain the bifurcation starting position.

[0091] S230. Determine the bifurcation end position based on the separation assessment data between the main vessel segment and the branch vessel segment.

[0092] The term "bifurcation point" indicates the point where branching segments originate from the main trunk segment in a vascular tree. Preliminary location data can be a rough estimate of the bifurcation point's location. Separation assessment data describes the degree of separation between the main trunk segment and the branching segments.

[0093] Specifically, before determining the start and end positions of vascular bifurcation, preliminary location data is determined based on the bifurcation point markers identified through prior segmentation and bifurcation point detection of the vascular tree. This data indicates the bifurcation points where branch segments originating from the main trunk segment of the vascular tree branch off. Using this preliminary location data as a reference point for determining the bifurcation start position, the minimum distance between the main trunk segment and the branch segment is calculated. When the minimum distance between the main trunk segment and the branch segment meets the requirements, the precise bifurcation start position is determined. Next, based on specific needs, an appropriate separation assessment index is selected to describe the degree of separation between the main trunk segment and the branch segment. Separation assessment data is determined based on the separation assessment index to evaluate the degree of separation between the main trunk segment and the branch segment. If the separation assessment data is large, indicating a high degree of separation between the main trunk segment and the branch segment, this position is considered to be on a branch vessel and is some distance from the bifurcation point. If the degree of separation is small, this position is considered the bifurcation end position.

[0094] It should be noted that each main trunk segment has a unique identifier (such as an index number) to distinguish different main trunk segments.

[0095] In the above implementation, firstly, preliminary location data is determined to indicate the bifurcation points of branch vessels originating from the main trunk segment in the vascular tree. Then, using this preliminary location data as a reference point, the distance between the main trunk segment and the branch vessel segment is minimized to obtain the precise bifurcation initiation position. Next, separation assessment data is determined to describe the degree of separation between the main trunk segment and the branch vessel segment. Finally, the bifurcation end position is determined based on the separation assessment data. Through this implementation, the initiation and end positions of vascular bifurcation can be accurately determined, thereby improving the image quality at the bifurcation point. Determining the initiation and end positions of vascular bifurcation facilitates vascular analysis and provides a reliable basis for diagnosis and treatment.

[0096] In some implementations, obtaining the bifurcation start position of the first and second vascular segments includes: determining preliminary position data of the bifurcation location based on the vascular centerline; and using the preliminary position data as a traversal reference point, calculating the minimum value of the distance between the first and second vascular segments to obtain the bifurcation start position.

[0097] Specifically, before determining the start and end positions of vascular bifurcation, preliminary positional data is determined based on the bifurcation point markers and vascular centerlines identified through prior segmentation and bifurcation point detection of the vascular tree. This data is used to indicate the bifurcation location of the second vascular segment arising from the first vascular segment in the vascular tree. Using this preliminary positional data as a traversal reference point for the bifurcation start position, the minimum distance between the first and second vascular segments is calculated. When the minimum distance between the first and second vascular segments meets the requirements, the precise bifurcation start position is determined.

[0098] In the above embodiments, preliminary location data of the bifurcation of the blood vessel is determined based on the blood vessel centerline; using the preliminary location data as a traversal reference point, the distance between the first blood vessel segment and the second blood vessel segment is minimized to accurately determine the bifurcation starting position of the blood vessel, thereby improving the image quality at the bifurcation point.

[0099] In some implementations, please refer to Figure 3a The vascular centerline includes the first vascular centerline of the first vascular segment and the second vascular centerline of the second vascular segment. Determining the preliminary location data of the vascular bifurcation point may include the following steps:

[0100] S302. Determine multiple main sampling points on the center line of the first blood vessel and multiple designated branch sampling points on the center line of the second blood vessel.

[0101] Among them, the multiple designated branch sampling points are a part of the multiple branch sampling points on the center line of the second blood vessel.

[0102] Specifically, multiple main sampling points are determined at certain intervals and according to a certain pattern on the first vascular segment to represent its morphology. Using the selected sampling point data, the first vascular centerline of the first vascular segment can be constructed using interpolation algorithms (such as linear interpolation and spline interpolation) and curve fitting methods (such as polynomial fitting and Bézier curve fitting). Similarly, multiple branch sampling points are determined at certain intervals and according to a certain pattern on the second vascular segment to represent its morphology. Using the selected sampling point data, the second vascular centerline of the second vascular segment can be constructed using interpolation algorithms (such as linear interpolation and spline interpolation) and curve fitting methods (such as polynomial fitting and Bézier curve fitting). To reduce computational load and conserve computational resources, a specified traversal step size can be determined. Starting from the initial sampling point on the second vascular centerline, multiple specified branch sampling points are determined from the branch sampling points on the second vascular centerline at intervals of the specified traversal step size, based on the second sampling position data on the second vascular centerline. Because the sampling points on the first and second vessel centerlines differ in density, a second distance threshold is set when calculating the corresponding distances between specified branch sampling points and main vessel sampling points to improve the accuracy of the initial location data. Based on the location data of the specified branch sampling point, the distance between that branch sampling point and the first vessel centerline is calculated. When the distance between the branch sampling point and the first vessel centerline is equal to the second distance threshold, a first preset distance range can be determined. Based on the first sampling location data on the first vessel centerline, it is determined that at least one main vessel sampling point is included within the first preset distance range.

[0103] S304. Along the blood flow direction, sequentially obtain the distance between the main trunk sampling point and the nearest branch sampling point. Based on the positions of the first designated branch sampling point and the main trunk sampling point whose distance is greater than the first distance threshold, determine the preliminary position data.

[0104] The first distance threshold is determined by the maximum preset distance between the center line of the first blood vessel and the center line of the second blood vessel.

[0105] Specifically, along the blood flow direction, the distance between a designated branch sampling point and each main trunk sampling point within a first preset distance range is calculated, and the shortest calculated distance is taken as the minimum distance corresponding to the designated branch sampling point. The minimum distance corresponding to the designated branch sampling point is compared with a first distance threshold. If the minimum distance corresponding to the designated branch sampling point is greater than the first distance threshold, preliminary bifurcation location can be performed, and the position data of the main trunk sampling point corresponding to the minimum distance of the designated branch sampling point is taken as preliminary position data. If the minimum distance corresponding to the designated branch sampling point is less than the first distance threshold, the minimum distance corresponding to the next designated branch sampling point is calculated along the blood flow direction. This process is repeated to sequentially obtain the distance between the nearest main trunk sampling point to the designated branch sampling point until the minimum distance corresponding to a certain designated branch sampling point is greater than the first distance threshold. At this point, the position data of the main trunk sampling point corresponding to the minimum distance of the designated branch sampling point is taken as preliminary position data.

[0106] In the above implementation, multiple main trunk sampling points on the centerline of the first blood vessel and multiple designated branch sampling points on the centerline of the second blood vessel are determined. Along the blood flow direction, the distances between the main trunk sampling points closest to the designated branch sampling points are sequentially acquired. Based on the positions corresponding to the first designated branch sampling point with a distance greater than a first distance threshold and the main trunk sampling point, preliminary position data is determined to accurately determine the starting and ending positions of the blood vessel bifurcation, thereby improving the image quality at the bifurcation point. Simultaneously, using designated branch sampling points reduces computational load and enables a "large-small-precise" determination process. "Large-small" means finding a small range (preliminary position data) that includes the bifurcation position within a large range, and then accurately determining the bifurcation position within that small range.

[0107] In some implementations, the first vascular segment can be a main vascular segment, and the second vascular segment can be a branch vascular segment.

[0108] Please see Figure 3b Determining the preliminary location data of the bifurcation point of a blood vessel may include the following steps:

[0109] S310. Determine the centerline of the first vessel of the main trunk segment and the centerline of the second vessel of the branch segment.

[0110] Specifically, the vascular tree and its main and branch segments are first determined. Then, multiple sampling points are determined at certain intervals and according to a specific pattern on the main vascular segment to represent its morphology. Using the selected sampling point data, the first vascular centerline of the main vascular segment can be constructed using interpolation algorithms (such as linear interpolation and spline interpolation) and curve fitting methods (such as polynomial fitting and Bézier curve fitting). Similarly, multiple sampling points are determined at certain intervals and according to a specific pattern on the branch vascular segments to represent their morphology. Using the selected sampling point data, the second vascular centerline of the branch vascular segment can be constructed using interpolation algorithms (such as linear interpolation and spline interpolation) and curve fitting methods (such as polynomial fitting and Bézier curve fitting).

[0111] S320. Based on the first distance threshold, the first sampling position data on the center line of the first blood vessel, and the second sampling position data on the center line of the second blood vessel, the bifurcation position is initially located to obtain preliminary position data.

[0112] The first distance threshold is determined by the maximum preset distance between the center line of the first blood vessel and the center line of the second blood vessel.

[0113] Specifically, along the blood flow direction, based on the first sampling position data on the centerline of the first blood vessel and the second sampling position data on the centerline of the second blood vessel, the distance between the sampling points on the centerline of the first blood vessel and the sampling points on the centerline of the second blood vessel is determined. This distance is then compared with a first distance threshold. When the distance is greater than the first distance threshold, preliminary location of the bifurcation point is achieved, obtaining preliminary location data.

[0114] In the above embodiments, the first vessel centerline of the main vessel segment and the second vessel centerline of the branch vessel segment are determined. Based on the first distance threshold, the first sampling position data on the first vessel centerline, and the second sampling position data on the second vessel centerline, the bifurcation position is initially located to obtain preliminary position data, so as to accurately determine the starting position and ending position of the vessel bifurcation in the subsequent process, thereby improving the image quality at the bifurcation point.

[0115] In some implementations, the first vascular segment may be a main vascular segment, and the second vascular segment may be a branch vascular segment. Please refer to [link / reference]. Figure 4a The preliminary location of the bifurcation point is determined based on a first distance threshold, first sampling position data on the center line of the first blood vessel, and second sampling position data on the center line of the second blood vessel. This preliminary location data may include the following steps:

[0116] S410. Determine the designated branch sampling point on the center line of the second blood vessel based on the second sampling position data and the specified traversal step size.

[0117] The specified traversal step size can refer to the interval distance between sampling points selected on the center line of the second blood vessel. For example, the specified traversal step size can be 5 or 8.

[0118] Specifically, to reduce computational load and conserve computational resources, a specified traversal step size can be determined. Starting from the initial sampling point on the center line of the second blood vessel, multiple specified branch sampling points are determined at intervals of the specified traversal step size, based on the second sampling position data on the center line of the second blood vessel.

[0119] For example, please refer to Figure 4b The specified traversal step size can be 5. On the second vessel centerline (Branch), T1 is the specified branch sampling point. Based on the position data of the specified branch sampling point T1, the next specified branch sampling point T2, with an interval of 5, is determined at the specified traversal step size. Then, based on the position data of the specified branch sampling point T2, the next specified branch sampling point T3, with an interval of 5, is determined again at the specified traversal step size. This process continues, and a series of equally spaced specified branch sampling points with an interval of 5 can be determined from multiple second sampling position data.

[0120] S420. Based on the location data of the specified branch sampling point and the first sampling location data, determine at least one main trunk sampling point located within a first preset distance range on the center line of the first blood vessel.

[0121] The first preset distance range is determined based on the location data of the specified branch sampling points and the second distance threshold.

[0122] Specifically, because the density of sampling points on the first and second vessel centerlines differs, a second distance threshold is set when calculating the corresponding distances between specified branch sampling points and main vessel sampling points to improve the accuracy of the initial location data. Based on the location data of the specified branch sampling point, the distance between that branch sampling point and the first vessel centerline is calculated. When the distance between the branch sampling point and the first vessel centerline is equal to the second distance threshold, a first preset distance range can be determined. Based on the first sampling location data on the first vessel centerline, it is determined that at least one main vessel sampling point is included within the first preset distance range.

[0123] For example, please continue reading Figure 4b The second distance threshold is Dis Thresh1 Specify branch sampling point T2. Based on the position data of the specified branch sampling point T2, when the distance between the specified branch sampling point T2 and the first vessel centerline Trunk is equal to the second distance threshold Dis... Thresh1When the above requirements are met, point A is determined that is located on the centerline of the first blood vessel. Based on the position data of the specified branch sampling point T2, when the distance between the specified branch sampling point T2 and the centerline of the first blood vessel is the second distance threshold Dis... Thresh1 At that time, point B, which meets the above requirements and is located on the center line of the first blood vessel, is determined. The line segment between point A and point B is represented as the first preset distance range.

[0124] S430. Determine the minimum distance between the specified branch sampling point and at least one main sampling point within the first preset distance range.

[0125] S440. Based on the specified branch sampling point and trunk sampling point corresponding to the minimum distance greater than the first distance threshold, perform preliminary location of the bifurcation position to obtain preliminary position data.

[0126] Specifically, the distance between a specified branch sampling point and each main trunk sampling point within a first preset distance range is calculated, and the shortest calculated distance is taken as the minimum distance corresponding to the specified branch sampling point. The minimum distance corresponding to the specified branch sampling point is compared with a first distance threshold. If the minimum distance corresponding to the specified branch sampling point is greater than the first distance threshold, preliminary bifurcation location can be performed, and the location data of the main trunk sampling point corresponding to the minimum distance of the specified branch sampling point is taken as preliminary location data. If the minimum distance corresponding to the specified branch sampling point is less than the first distance threshold, the minimum distance corresponding to the next specified branch sampling point is calculated along the blood flow direction. This process is repeated until the minimum distance corresponding to a certain specified branch sampling point is greater than the first distance threshold; at this point, the location data of the main trunk sampling point corresponding to the minimum distance of the specified branch sampling point is taken as preliminary location data.

[0127] For example, please refer to Figure 4c The specified traversal step size is represented as Step. Branch Set the first distance threshold Dis ThreshMax This is used to control the number of calculations. For accurate calculations, it is necessary to sequentially traverse the specified branch sampling points along the blood flow direction and calculate the minimum distance corresponding to each specified branch sampling point until a minimum distance value corresponding to a specified branch sampling point is found that is greater than a first distance threshold Dis. ThreshMax If the calculation stops, the location data of the main sampling point at this time is recorded as the preliminary location data.

[0128] In the above embodiments, a designated branch sampling point is determined on the center line of the second blood vessel based on the second sampling position data and the specified traversal step size. Based on the position data of the designated branch sampling point and the first sampling position data, at least one main trunk sampling point located within a first preset distance range is determined on the center line of the first blood vessel. The minimum distance between the designated branch sampling point and at least one main trunk sampling point within the preset distance range is determined. The bifurcation position is initially located based on the designated branch sampling point and the main trunk sampling point corresponding to the minimum distance greater than the first distance threshold, so as to obtain preliminary position data for subsequent accurate determination of the start position and end position of the blood vessel bifurcation.

[0129] In some implementations, please refer to Figure 5a The vascular centerline includes the first vascular centerline of the first vascular segment and the second vascular centerline of the second vascular segment. Using preliminary location data as a traversal reference point, the distance between the first and second vascular segments is minimized to obtain the bifurcation starting position. This may include the following steps:

[0130] S510. Following the opposite direction of blood flow, starting from the preliminary location data, traverse the distance between the main sampling point of the first blood vessel centerline and the branch sampling point of the second blood vessel centerline to obtain the minimum distance value.

[0131] S520. Based on the branch sampling point and the trunk sampling point corresponding to the first minimum distance value that is less than the third distance threshold, the starting position of the fork is obtained.

[0132] The third distance threshold is determined by the minimum preset distance between the center lines of the first and second blood vessels.

[0133] Specifically, in the opposite direction of blood flow, for accuracy, starting from the initial position data, the distances between branch sampling points on the second vessel centerline and the first vessel centerline are calculated sequentially. When the distance between the branch sampling point and the first vessel centerline is a preset distance, a second preset distance range can be determined. The distance between the branch sampling point and each main trunk sampling point within the second preset distance range is calculated, and the distances between the branch sampling point and each main trunk sampling point within the second preset distance range are traversed. The shortest distance among the calculated distances is determined and used as the minimum distance value corresponding to the branch sampling point. The minimum distance value corresponding to the branch sampling point is compared with a third distance threshold. If the minimum distance value corresponding to the branch sampling point is less than the third distance threshold, the position data of the main trunk sampling point corresponding to the minimum distance value is used as the starting position of the bifurcation. If the minimum distance value corresponding to the branch sampling point is greater than the third distance threshold, the minimum distance value corresponding to the next branch sampling point is calculated in the opposite direction of blood flow. Repeat the above operation until the minimum distance value corresponding to a certain branch sampling point is less than the third distance threshold. Then, determine that branch sampling point as the first branch sampling point corresponding to a minimum distance value less than the third distance threshold. Use the location data of the main branch sampling point corresponding to the minimum distance value of that branch sampling point as the starting position of the fork.

[0134] For example, please refer to Figure 5b Set the third distance threshold Dis ThreshMin This is used to control the number of calculations. For accurate calculations, the reverse calculation needs to iterate through the branch sampling points before the initial position data until a minimum distance corresponding to a certain branch sampling point is found that is less than the third distance threshold Dis. ThreshMin If the calculation stops, the location data of the main sampling point at this time is recorded as the bifurcation starting point. Begin .

[0135] In the above implementation, the distance between the main sampling point of the first blood vessel centerline and the branch sampling point of the second blood vessel centerline is traversed along the opposite direction of blood flow, starting from the preliminary position data, to obtain the minimum distance value. Based on the branch sampling point and the main sampling point corresponding to the first minimum distance value that is less than the third distance threshold, the bifurcation start position is obtained. The starting position of blood vessel bifurcation can be accurately determined, thereby improving the quality and accuracy of the image at the bifurcation point.

[0136] In some implementations, the bifurcation end position of the first and second vascular segments is obtained as follows: taking the bifurcation start position as a reference point, multiple orthogonal visual planes are determined along the first vascular centerline of the first vascular segment, with the orthogonal visual planes perpendicular to the first vascular centerline; based on the tissue image, separation evaluation data of the first and second vascular segments are obtained on each orthogonal visual plane; the position corresponding to the orthogonal visual plane where the separation evaluation data meets the separation evaluation threshold is determined as the bifurcation end position.

[0137] Among them, the separation assessment threshold can be used as a standard to determine the degree of separation between the first vascular segment and the second vascular segment.

[0138] Specifically, taking the bifurcation initiation position as a reference point, and using the main trunk sampling point on the first vessel centerline as the center point, a plane perpendicular to the first vessel centerline is determined as the orthogonal plane of the field of view. Since there are multiple main trunk sampling points on the first vessel centerline starting from the bifurcation initiation position (as the reference point), each main trunk sampling point along the first vessel centerline of the first vessel segment corresponds to a field of view orthogonal plane, thus determining multiple field of view orthogonal planes. Based on specific needs and tissue images, an appropriate separation evaluation index is selected to describe the degree of separation between the first and second vessel segments. According to the separation evaluation index, separation evaluation data between the first and second vessel segments on each field of view orthogonal plane is determined to assess the degree of separation between them. If the separation evaluation data meets the separation evaluation threshold, the position corresponding to the field of view orthogonal plane that meets the separation evaluation threshold is determined as the bifurcation end position. The separation evaluation threshold can be determined based on specific application requirements and actual conditions.

[0139] In the above embodiments, taking the bifurcation start position as a reference point, multiple orthogonal visual planes are determined along the first vessel centerline of the first vessel segment, and the orthogonal visual planes are perpendicular to the first vessel centerline; based on the tissue image, separation evaluation data of the first and second vessel segments are obtained on each orthogonal visual plane; the position corresponding to the orthogonal visual plane where the separation evaluation data meets the separation evaluation threshold is determined as the bifurcation end position, which can accurately determine the end position of the vessel bifurcation, thereby improving the quality and accuracy of the image at the bifurcation point.

[0140] In some embodiments, the first vascular segment can be a main vascular segment, and the second vascular segment can be a branch vascular segment. Based on tissue images, separation assessment data of the first and second vascular segments are acquired on each orthogonal plane of the field of view. Accordingly, in this embodiment, please refer to... Figure 6a The separation assessment data were determined in the following ways:

[0141] S610. Determine the first intersection point of the first vessel centerline of the main vessel segment with the designated visual field, and the second intersection point of the second vessel centerline of the branch vessel segment with the designated visual field.

[0142] The designated field of view is one of a plurality of orthogonal fields of view orthogonal to the center line of the first blood vessel.

[0143] Specifically, the main sampling point on the centerline of the first blood vessel is taken as the center point, and a plane orthogonal to the centerline of the first blood vessel is determined as the orthogonal plane of the field of view. There are multiple main sampling points on the centerline of the first blood vessel. Since each main sampling point corresponds to a corresponding orthogonal plane of the field of view, there are multiple orthogonal planes of the field of view. Any one of these orthogonal planes of the field of view is selected as the designated field of view. The intersection of the centerline of the first blood vessel segment of the main blood vessel segment and the designated field of view is taken as the first intersection point, and the first intersection of the centerline of the second blood vessel segment of the branch blood vessel segment and the designated field of view is taken as the second intersection point.

[0144] For example, a series of images parallel to the xoy plane are reconstructed into several orthogonal view planes centered on the main sampling points on the centerline of the first blood vessel and orthogonal to the centerline of the first blood vessel. Please refer to [link to relevant documentation]. Figure 6b , Figure 6b The blue rectangle in the image represents the orthogonal plane of the field of view.

[0145] S620. Based on the tissue image, determine the specified pixel data corresponding to the line connecting the first intersection point and the second intersection point, as well as the pixel data at the first intersection point and the pixel data at the second intersection point.

[0146] S630. Determine separation evaluation data based on the degree of difference between the specified pixel data and the pixel data at the first intersection point and the pixel data at the second intersection point; or, obtain separation evaluation data based on the degree of difference between the specified pixel data and the pixel data at the first intersection point and the pixel data at the second intersection point, as well as the distance between the first intersection point and the second intersection point.

[0147] The separation assessment data can be an assessment of vascular bifurcation based on the intersection of a specified field of view and the vascular centerline, as well as related pixel data.

[0148] Specifically, in the tissue image, pixel data at the first intersection point and pixel data at the second intersection point are determined based on the pixel values ​​corresponding to various locations in the tissue image. Furthermore, depending on the specific situation and actual needs, the specified pixel data corresponding to the line connecting the first and second intersection points (e.g., the minimum pixel data corresponding to the line connecting the first and second intersection points) is determined. In some implementations, appropriate methods (such as Euclidean distance, difference, etc.) are used to calculate the degree of difference between the specified pixel data and the pixel data at the first and second intersection points, and the separation evaluation data corresponding to the specified field of view is determined based on the degree of difference. For example, the ratio between the specified pixel data and the pixel data at the first and second intersection points is calculated, and this ratio can be used to judge the degree of difference. When the ratio is close to 1, the degree of difference can be considered small; when the ratio is greater than or less than 1, the degree of difference can be considered large.

[0149] In other implementations, a distance metric (such as Euclidean distance or Manhattan distance) is used to calculate the distance between the first and second intersection points. Then, the degree of difference between the specified pixel data and the pixel data at the first and second intersection points, along with the distance between the first and second intersection points, is substituted into a formula to perform a separation evaluation, obtaining separation evaluation data corresponding to the specified field of view. The pixel data can be CT values.

[0150] For example, please refer to Figure 6c CT Value0 CT represents the pixel data at the first intersection point. Value1 This represents the pixel data at the second intersection point, CT. ValueMin Dis represents specified pixel data. 0-1 The distance between the first and second intersection points is represented by , and the Score represents the separation evaluation data. The formula for determining the separation evaluation data corresponding to a given field of view is as follows:

[0151]

[0152] Please continue reading. Figure 6c There are multiple orthogonal view planes. The first orthogonal view plane corresponds to the separation evaluation data Score1, the second orthogonal view plane corresponds to the separation evaluation data Score2, and the nth orthogonal view plane corresponds to the separation evaluation data Score. n .

[0153] In the above embodiments, the first intersection point of the first vessel centerline of the main vessel segment and the designated field of view, and the second intersection point of the second vessel centerline of the branch vessel segment and the designated field of view are determined. Based on the tissue image, the designated pixel data corresponding to the line connecting the first and second intersection points, the pixel data at the first intersection point, and the pixel data at the second intersection point are determined. Separation evaluation data are determined according to the degree of difference between the designated pixel data and the pixel data at the first and second intersection points; or, separation evaluation data are obtained according to the degree of difference between the designated pixel data and the pixel data at the first and second intersection points, as well as the distance between the first and second intersection points, so as to subsequently determine a more accurate bifurcation end position.

[0154] Determining the bifurcation location using the vessel centerline and distance threshold is potentially inaccurate because it doesn't consider vessel contour (or diameter) information and is easily affected by the distance threshold setting. For example, if the distance threshold is set too low, the first and second vessel segments may not yet be separated. Or, at the same distance threshold, the first and second vessel segments with smaller contours may be determined to be separated, while the first and second vessel segments with larger contours may still be in a state of separation. The above embodiment utilizes not only vessel centerline information but also pixel information from the tissue image. By using differences in pixel information to determine the bifurcation end position, it avoids the potential inaccuracies of using only the vessel centerline and distance threshold, thus improving the accuracy of bifurcation end position determination. Specifically, the pixel data at the first and second intersection points represent the positional information within the blood vessel, while the specified pixel data represents the positional information between blood vessels. If the specified field of view is located upstream of the bifurcation end point, it indicates that the specified pixel data represents blood vessel information. In this case, the specified pixel data and the pixel data at the first and second intersection points are all blood vessel information with minimal differences, indicating that the first and second blood vessel segments are not separated at this specified field of view. If the specified field of view is located at or downstream of the bifurcation end point, the specified pixel data represents the tissue information outside the blood vessel, generally with a smaller CT value, less than the CT value of the blood vessel. In this case, the specified pixel data and the pixel data at the first and second intersection points have significant differences, indicating that the first and second blood vessel segments are separated at this specified field of view.

[0155] In some implementations, please refer to Figure 7 Determining the bifurcation termination location based on separation assessment data between the main vessel segment and branch vessel segments may include the following steps:

[0156] S710, Obtain the separation evaluation threshold.

[0157] S720. Determine the location of the end sampling point corresponding to the separation evaluation data that is less than the separation evaluation threshold.

[0158] S730, Determine the end position of the bifurcation based on the position of the end sampling point.

[0159] The separation assessment threshold can be a critical value obtained by observing and measuring blood vessels to determine the end position of blood vessel bifurcation, such as the shape, size, and location of the blood vessel.

[0160] Specifically, based on the actual situation and specific needs, a separation assessment threshold (Score) is determined to identify the end position of a vessel bifurcation. Thresh Along the blood flow direction, starting from the first orthogonal visual field, the separation assessment data corresponding to each orthogonal visual field is compared with the separation assessment threshold, until the separation assessment data corresponding to a certain orthogonal visual field is less than the separation assessment threshold (Score). Thresh At that time, the location data of the main trunk sampling point located on the orthogonal plane of the field of view and simultaneously on the center line of the first blood vessel is used as the end sampling point location (Bifurcation). End The location of the end sampling point (Bifurcation) End It serves as the bifurcation point between the main vascular segment and the branch vascular segment.

[0161] In the above embodiments, a separation evaluation threshold is obtained, the end sampling point position corresponding to the separation evaluation data that is less than the separation evaluation threshold is determined, and the bifurcation end position is determined based on the end sampling point position. This can accurately determine the end position of blood vessel bifurcation, thereby improving the quality and accuracy of the image at the bifurcation point.

[0162] In some implementations, the specified pixel data is the minimum grayscale or CT value of the pixels traversed by the line connecting the first and second intersection points. The second intersection point is determined as follows: adjacent first and second sampling points are determined on the center line of the second blood vessel segment; if the first and second sampling points are located on different sides of the specified field of view based on the position data of the first and second sampling points and the normal vector of the specified field of view, the intersection point of the line segment between the first and second sampling points and the specified field of view is taken as the second intersection point.

[0163] The first vascular segment can be a main vascular segment, and the second vascular segment can be a branch vascular segment. Accordingly, in this embodiment, please refer to... Figure 8a The second intersection point is determined in the following way:

[0164] S810. Determine the adjacent first and second sampling points on the center line of the second blood vessel of the branch vessel segment.

[0165] S820. If the first sampling point and the second sampling point are located on different sides of the specified field of view based on the position data of the first sampling point, the position data of the second sampling point, and the normal vector of the specified field of view, the intersection of the line segment between the first sampling point and the second sampling point with the specified field of view is taken as the second intersection point.

[0166] In some cases, the centerline of the second vessel in a branch vessel segment consists of a series of discrete points, making it impossible to accurately determine the intersection point with a specified field of view using a defined curve equation.

[0167] Specifically, when calculating the intersection point of the second vessel centerline and the specified visual field plane, since the second vessel centerline is a curve with an uncertain trajectory, the number of intersection points may not be unique. Therefore, the first intersection point of the second vessel centerline and the specified visual field plane is taken as the second intersection point. The normal vector of the specified visual field plane is calculated to determine whether two adjacent sampling points are located on different sides of the specified visual field plane. Along the blood flow direction, adjacent sampling points on the second vessel centerline are traversed, and adjacent sampling points are taken as the first sampling point and the second sampling point, respectively.

[0168] Based on the position data of the first sampling point and the normal vector of the specified field of view, calculate the directed distance between the first sampling point and the normal vector of the specified field of view. Based on the position data of the second sampling point and the normal vector of the specified field of view, calculate the directed distance between the second sampling point and the normal vector of the specified field of view. If the directed distances between the first sampling point and the normal vector of the specified field of view and the directed distances between the second sampling point and the normal vector of the specified field of view are in opposite directions, then the first sampling point and the second sampling point are determined to be on different sides of the specified field of view.

[0169] If the directed distances between the first sampling point and the normal vector of the specified field of view, and the directed distances between the second sampling point and the normal vector of the specified field of view, are in the same direction, then continue traversing the subsequent adjacent sampling points along the blood flow direction. These adjacent sampling points are then designated as the first and second sampling points, respectively. The directed distances between the first and second sampling points and the normal vector of the specified field of view are then recalculated. This process is repeated until the directed distances between the first and second sampling points and the normal vector of the specified field of view are found to be in opposite directions, thus determining that the first and second sampling points are located on different sides of the specified field of view.

[0170] After determining that the first sampling point and the second sampling point are located on different sides of the specified field of view, the intersection point of the line segment between the first sampling point and the second sampling point and the specified field of view is determined and taken as the second intersection point.

[0171] For example, please refer to Figure 8bThe intersection point between the centerline of the second blood vessel and the designated visual field is not unique. Therefore, the first intersection point between the centerline of the second blood vessel and the designated visual field is taken as the second intersection point.

[0172] Orthogonal plane normal vector of specified view plane The location data of the first sampling point is (x0, y0, z0), and the location data of the second sampling point is (x1, y1, z1). Based on the location data of the first sampling point and the normal vector of the specified view surface, the directed distance Dis between the first sampling point and the normal vector of the specified view surface is calculated. point-plane0 Based on the position data of the second sampling point and the normal vector of the specified field of view, the directed distance between the second sampling point and the normal vector of the specified field of view is calculated as Dis. point-plane1 Directed distance Dis point-plane0 With directed distance Dis point-plane1 If the directions are opposite, then the intersection point A0 of the line segment between the first sampling point and the second sampling point and the specified field of view is the first intersection point between the center line of the second blood vessel and the specified field of view, so intersection point A0 is taken as the second intersection point. Although intersection points A1 and A2 are intersection points between the center line of the second blood vessel and the specified field of view, they are not the first intersection points along the blood flow direction, so intersection points A1 and A2 cannot be taken as the second intersection points.

[0173] In the above embodiments, adjacent first and second sampling points are determined on the center line of the second blood vessel of the branch vessel segment. If the first and second sampling points are located on different sides of the specified field of view based on the position data of the first sampling point, the position data of the second sampling point, and the normal vector of the specified field of view, the intersection of the line segment between the first and second sampling points and the specified field of view is taken as the second intersection point, which provides a basis for subsequent determination of separation evaluation data so as to determine the end position of the bifurcation.

[0174] In some embodiments, the method may further include: determining a starting sampling point and an ending sampling point along the blood flow direction on the vascular centerline of a plurality of undetermined second vascular segments; for any undetermined second vascular segment, determining the initial closest distance between the starting sampling point and the vascular centerline of the first vascular segment, and the ending closest distance between the ending sampling point and the first vascular segment; determining undetermined second vascular segments whose initial closest distance is less than a fourth distance threshold and whose ending closest distance is greater than the fourth distance threshold as undetermined second vascular segments that are branch vascular segments that originate from the first vascular segment.

[0175] The "undetermined second vessel segment" may be a segment whose branching nature is yet to be determined and requires further analysis and assessment. The starting sampling point can be a point selected along the blood flow direction at the beginning of the undetermined second vessel segment. The ending sampling point can be a point selected along the blood flow direction at the end of the undetermined second vessel segment. The starting and ending sampling points can be determined based on factors such as the location and morphology of the vessel branch. The closest starting distance can be the distance between the starting sampling point on the undetermined second vessel segment and the closest sampling point on the first vessel segment. The closest ending distance can be the distance between the ending sampling point on the undetermined second vessel segment and the closest sampling point on the first vessel segment.

[0176] Specifically, multiple potential second vascular segments are determined based on the structure of the vascular tree. Then, along the blood flow direction, a point is selected at the beginning of each potential second vascular segment as the starting sampling point, and a point is selected at the end of each potential second vascular segment as the ending sampling point. Along the blood flow direction, sampling points near the starting sampling points are determined on the vascular centerline of the first vascular segment. For any potential second vascular segment, a distance metric (such as Euclidean distance) is used to calculate the distance between each sampling point near the starting sampling point on the vascular centerline of the first vascular segment and the starting sampling point. Then, the shortest distance is selected from the calculated distances as the initial closest distance between the starting sampling point and the vascular centerline of the first vascular segment. Similarly, along the blood flow direction, sampling points near the ending sampling points are determined on the vascular centerline of the first vascular segment. A distance metric (such as Euclidean distance) is used to calculate the distance between each sampling point near the ending sampling point on the vascular centerline of the first vascular segment and the ending sampling point. Finally, the shortest distance is selected from the calculated distances as the final closest distance between the ending sampling point and the vascular centerline of the first vascular segment. When the initial nearest distance is less than the fourth distance threshold, the undetermined second vascular segment can be considered to be close to and continuous with the first vascular segment. When the final nearest distance is greater than the fourth distance threshold, it indicates that the distance between the two gradually increases as the undetermined second vascular segment extends outward from the first vascular segment. In summary, the undetermined second vascular segment is determined to be a branch segment originating from the first vascular segment.

[0177] In the above embodiments, along the blood flow direction, starting and ending sampling points are determined on the vessel centerline of multiple undetermined second vessel segments. For any undetermined second vessel segment, the starting closest distance between the starting sampling point and the vessel centerline of the first vessel segment, and the ending closest distance between the ending sampling point and the first vessel segment are determined. Undetermined second vessel segments whose starting closest distance is less than a fourth distance threshold and whose ending closest distance is greater than the fourth distance threshold are determined as branch vessel segments that originate from the first vessel segment. This is used to determine whether the undetermined second vessel segment needs to participate in the subsequent identification of vessel bifurcation positions, thereby reducing the amount of computation and improving the accuracy of vessel bifurcation position identification.

[0178] In some implementations, please refer to Figure 9 The vascular tree is the coronary tree; the main trunk segment is any one of the main coronary artery segments from the right coronary artery, the left anterior descending artery, and the left circumflex artery; the method may also include:

[0179] S910. Along the direction of blood flow, determine the starting and ending sampling points on the non-main coronary artery segments of the coronary tree.

[0180] The initial sampling point can be a point selected along the blood flow direction at the beginning of a non-main coronary artery segment on the coronary tree. The final sampling point can be a point selected along the blood flow direction at the end of a non-main coronary artery segment on the coronary tree.

[0181] Specifically, non-major coronary artery segments are identified on the coronary tree. Then, along the blood flow direction, a point is selected at the beginning of the non-major coronary artery segment as the starting sampling point, and a point is selected at the end of the non-major coronary artery segment as the ending sampling point.

[0182] For example, a neural network model is used to identify the coronary artery tree and determine the non-main coronary artery segments and main coronary artery segments on the tree. Then, based on the non-main coronary artery segments, multiple sampling points can be determined, and these multiple sampling points constitute the centerline of the non-main coronary artery segments. Based on the main coronary artery segments, multiple sampling points can be determined, and these multiple sampling points constitute the centerline of the main coronary artery segments. Along the blood flow direction, the sampling point at the foremost point on the centerline of the non-main coronary artery segment is determined as the starting sampling point, and the sampling point at the end point on the centerline of the non-main coronary artery segment is determined as the ending sampling point.

[0183] S920. Determine the closest distance between the starting sampling point and the main coronary artery segment, and the closest distance between the ending sampling point and the ending of the main coronary artery segment.

[0184] The initial nearest distance can be the distance between the initial sampling point on the non-main coronary artery segment and the nearest sampling point on the main coronary artery segment. The final nearest distance can be the distance between the final sampling point on the non-main coronary artery segment and the nearest sampling point on the main coronary artery segment.

[0185] Specifically, along the blood flow direction, sampling points are determined near the initial sampling point on the centerline of the main coronary artery segment. The distance between each sampling point near the initial sampling point on the centerline of the main coronary artery segment and the initial sampling point is calculated using a distance metric (such as Euclidean distance). Then, the shortest distance among the calculated distances is selected as the initial closest distance Dis between the initial sampling point and the main coronary artery segment. begin Along the blood flow direction, identify sampling points near the end sampling point on the centerline of the main coronary artery segment. Calculate the distance between each sampling point near the end sampling point on the centerline of the main coronary artery segment and the end sampling point using a distance metric (such as Euclidean distance). Then, select the shortest distance from the calculated distances as the nearest distance Dis between the end sampling point and the end of the main coronary artery segment. end .

[0186] S930. Identify non-main coronary artery segments on the coronary tree based on the closest starting distance and the closest ending distance to determine whether the non-main coronary artery segments originate from the main coronary artery segments.

[0187] Specifically, to ensure sufficient proximity and continuity between the bifurcation points of non-main coronary artery segments and main coronary artery segments, the initial nearest distance is used to determine whether a non-main coronary artery segment originates from a main coronary artery segment. Since non-main coronary artery segments originate from main coronary artery segments, the distance between them gradually increases. Therefore, the final nearest distance is used to identify non-main coronary artery segments on the coronary tree to determine whether they extend beyond the main coronary artery segment. In summary, both the initial and final nearest distances are used to identify non-main coronary artery segments on the coronary tree to determine whether they are branch segments originating from main coronary artery segments.

[0188] In the above embodiments, along the blood flow direction, a starting sampling point and an ending sampling point are determined on the non-main coronary artery segments on the coronary tree. The starting closest distance between the starting sampling point and the main coronary artery segment, and the ending closest distance between the ending sampling point and the main coronary artery segment are determined. Based on the starting closest distance and the ending closest distance, the non-main coronary artery segments on the coronary tree are identified to determine whether the non-main coronary artery segments originate from the main coronary artery segments. This is used to determine whether the non-main coronary artery segments need to participate in the subsequent identification of vessel bifurcation positions, thereby reducing the amount of computation and improving the accuracy of vessel bifurcation position identification.

[0189] In some implementations, identifying non-main coronary artery segments on the coronary tree based on the starting nearest distance and the ending nearest distance may include: if the starting nearest distance is greater than a fourth distance threshold and the ending nearest distance is greater than a fourth distance threshold, determining that the non-main coronary artery segment does not originate from a main coronary artery segment.

[0190] The fourth distance threshold is used to determine whether a non-main coronary artery segment branches off from the main coronary artery segment. The fourth distance threshold is set according to the actual situation and specific needs. For example, the fourth distance threshold can be 2mm.

[0191] Specifically, in order to ensure that there is sufficient proximity and continuity between the bifurcation location of the non-main coronary artery segment and the main coronary artery segment, a fourth distance threshold is determined to determine whether the non-main coronary artery segment is a branch segment that originates from the main coronary artery segment.

[0192] When the closest distance between the starting sampling point on a non-main coronary artery segment and the starting point of the main coronary artery segment is greater than the fourth distance threshold, it indicates that the non-main coronary artery segment branches off from outside the main coronary artery segment and does not meet the definition of a bifurcation segment. Since the non-main coronary artery segment originates from the main coronary artery segment, the distance between the non-main coronary artery segment and the main coronary artery segment gradually increases. Therefore, when the closest distance between the ending sampling point on the non-main coronary artery segment and the ending point of the main coronary artery segment is greater than the fourth distance threshold, it indicates that the distance between them gradually increases as the non-main coronary artery segment extends outward from the main coronary artery segment. In summary, when both the closest starting and ending distances are greater than the fourth distance threshold, the non-main coronary artery segment is determined not to be a branch segment originating from the main coronary artery segment.

[0193] For example, please refer to Figure 10a If the initial nearest distance Dis begin Greater than the fourth distance threshold Dis Thresh And the closest distance to the end Dis end Greater than the fourth distance threshold Dis Thresh This confirms that the non-main coronary artery segment Branch is not a branch segment that originates from the main coronary artery segment Trunk.

[0194] Please see Figure 10b If the initial nearest distance Dis begin Greater than the fourth distance threshold Dis Thresg And the closest distance to the end Dis end Greater than the fourth distance threshold Dis Tgresh This confirms that the non-main coronary artery segment Branch is not a branch segment that originates from the main coronary artery segment Trunk.

[0195] In the above implementation, if the starting nearest distance is greater than the fourth distance threshold and the ending nearest distance is greater than the fourth distance threshold, it is determined that the non-main coronary artery segment does not originate from the main coronary artery segment. In this case, the non-main coronary artery segment does not need to participate in the subsequent identification of the bifurcation position, thereby reducing the amount of computation and improving the accuracy of the identification of the bifurcation position.

[0196] In some implementations, identifying non-main coronary artery segments on the coronary tree based on the starting nearest distance and the ending nearest distance may include: if the starting nearest distance is greater than a fourth distance threshold and the ending nearest distance is less than the fourth distance threshold, determining that the non-main coronary artery segment does not originate from a main coronary artery segment.

[0197] Specifically, when the closest distance between the starting sampling point on a non-main coronary artery segment and the starting point of the main coronary artery segment is greater than the fourth distance threshold, it indicates that the non-main coronary artery segment branches off from outside the main coronary artery segment and does not meet the definition of a bifurcation segment. Since the non-main coronary artery segment originates from the main coronary artery segment, the distance between the non-main coronary artery segment and the main coronary artery segment gradually increases. Therefore, when the closest distance between the ending sampling point on a non-main coronary artery segment and the ending point of the main coronary artery segment is less than the fourth distance threshold, it indicates that the non-main coronary artery segment does not extend beyond the main coronary artery segment. In summary, when the closest starting distance is greater than the fourth distance threshold and the closest ending distance is less than the fourth distance threshold, the non-main coronary artery segment is determined not to be a branch segment originating from the main coronary artery segment.

[0198] For example, please refer to Figure 10c If the initial nearest distance Dis begin Greater than the fourth distance threshold Dis Thresh And the closest distance to the end Dis end Less than the fourth distance threshold Dis Thresh This confirms that the non-main coronary artery segment Branch is not a branch segment that originates from the main coronary artery segment Trunk.

[0199] Please see Figure 10d If the initial nearest distance Dis begin Greater than the fourth distance threshold Dis Thresg And the closest distance to the end Dis end Less than the fourth distance threshold Dis Tgresh This confirms that the non-main coronary artery segment Branch is not a branch segment that originates from the main coronary artery segment Trunk.

[0200] In the above implementation, if the starting nearest distance is greater than the fourth distance threshold and the ending nearest distance is less than the fourth distance threshold, it is determined that the non-main coronary artery segment does not originate from the main coronary artery segment. In this case, the non-main coronary artery segment does not need to participate in the subsequent identification of the bifurcation position, thereby reducing the amount of computation and improving the accuracy of the identification of the bifurcation position.

[0201] In some implementations, identifying non-main coronary artery segments on the coronary tree based on the starting nearest distance and the ending nearest distance may include: if the starting nearest distance is less than a fourth distance threshold and the ending nearest distance is less than a fourth distance threshold, determining that the non-main coronary artery segment does not originate from a main coronary artery segment.

[0202] Specifically, when the closest initial sampling point on a non-main coronary artery segment is less than the fourth distance threshold between the initial sampling point and the initial sampling point on the main coronary artery segment, the non-main coronary artery segment can be considered close to and continuous with the main coronary artery segment. Since the non-main coronary artery segment originates from the main coronary artery segment, the distance between them gradually increases. Therefore, when the closest initial sampling point on a non-main coronary artery segment is less than the closest initial sampling point on the initial sampling point and the closest initial sampling point on the initial sampling point is less than the fourth distance threshold, it indicates that the non-main coronary artery segment does not extend beyond the main coronary artery segment. In summary, when both the initial closest sampling point and the final closest sampling point are less than the fourth distance threshold, the non-main coronary artery segment is determined not to be a branch segment originating from the main coronary artery segment.

[0203] In the above implementation, if the starting nearest distance is less than the fourth distance threshold and the ending nearest distance is less than the fourth distance threshold, it is determined that the non-main coronary artery segment does not originate from the main coronary artery segment. In this case, the non-main coronary artery segment does not need to participate in the subsequent identification of the bifurcation position, thereby reducing the amount of computation and improving the accuracy of the identification of the bifurcation position.

[0204] In some implementations, identifying non-main coronary artery segments on the coronary tree based on the starting nearest distance and the ending nearest distance may include: if the starting nearest distance is less than a fourth distance threshold and the ending nearest distance is greater than the fourth distance threshold, determining that the non-main coronary artery segment originates from a main coronary artery segment.

[0205] Specifically, when the closest initial sampling point on a non-main coronary artery segment is less than the fourth distance threshold between the initial sampling point and the main coronary artery segment, the non-main coronary artery segment and the main coronary artery segment can be considered close and continuous. Since the non-main coronary artery segment originates from the main coronary artery segment, the distance between them gradually increases. Therefore, when the closest initial sampling point on a non-main coronary artery segment is greater than the closest initial distance between the final sampling point and the main coronary artery segment, it indicates that the distance between them gradually increases as the non-main coronary artery segment extends outward from the main coronary artery segment. In summary, when the closest initial distance is less than the fourth distance threshold and the closest initial final distance is greater than the fourth distance threshold, the non-main coronary artery segment is determined to be a branch segment originating from the main coronary artery segment.

[0206] For example, please refer to Figure 10e If the initial nearest distance Dis begin Less than the fourth distance threshold Dis Thresh And the closest distance to the end Dis end Greater than the fourth distance threshold Dis Thresh It was determined that the non-main coronary artery segment Branch is a branch segment that originates from the main coronary artery segment Trunk.

[0207] In the above implementation, if the initial nearest distance is less than the fourth distance threshold and the final nearest distance is greater than the fourth distance threshold, it is determined that the non-main coronary artery segment originates from the main coronary artery segment, providing a data basis for subsequent identification of the bifurcation location and reducing the computational workload of identifying the bifurcation location.

[0208] This specification also provides a method for identifying the location of blood vessel bifurcation. The vascular tree is a coronary artery tree; the main trunk segment is any one of the main coronary artery segments: the right coronary artery, the left anterior descending artery, or the left circumflex artery. For example, please refer to... Figure 11 The method for identifying the bifurcation location of the blood vessel may include the following steps:

[0209] S1102. Along the direction of blood flow, determine the starting and ending sampling points on the non-main coronary artery segments of the coronary tree.

[0210] S1104. Determine the closest distance between the starting sampling point and the main coronary artery segment, and the closest distance between the ending sampling point and the ending coronary artery segment.

[0211] S1106. If the initial nearest distance is less than the fourth distance threshold and the final nearest distance is greater than the fourth distance threshold, it is determined that the non-main coronary artery segment originates from the main coronary artery segment.

[0212] S1108. Determine the center line of the first vessel of the main coronary artery segment and the center line of the second vessel of the non-main coronary artery segment.

[0213] S1110. Determine the specified branch sampling point on the center line of the second blood vessel based on the second sampling position data and the specified traversal step size.

[0214] S1112. Based on the location data of the specified branch sampling points and the first sampling location data, determine at least one main trunk sampling point located within a first preset distance range on the center line of the first blood vessel.

[0215] The first preset distance range is determined based on the location data of the specified branch sampling point and the second distance threshold.

[0216] S1114. Determine the minimum distance between the specified branch sampling point and at least one main sampling point within the first preset distance range.

[0217] S1116. Based on the specified branch sampling points and trunk sampling points corresponding to the minimum distance greater than the first distance threshold, perform preliminary location of the bifurcation position to obtain preliminary position data.

[0218] The first distance threshold is determined by the maximum preset distance between the center line of the first blood vessel and the center line of the second blood vessel.

[0219] S1118. Following the opposite direction of blood flow, starting from the initial location data, traverse the distance between the main coronary artery segment and the non-main coronary artery segment to obtain the minimum distance value.

[0220] S1120. Based on the branch sampling points and trunk sampling points corresponding to the minimum distance values ​​less than the third distance threshold, the starting position of the bifurcation is obtained.

[0221] The third distance threshold is determined by the minimum preset distance between the center lines of the first and second blood vessels.

[0222] S1122. Determine the first intersection point between the first vessel centerline of the main coronary artery segment and the designated visual field plane, wherein the designated visual field plane is one of a plurality of orthogonal visual field planes orthogonal to the first vessel centerline.

[0223] S1124. Determine the adjacent first and second sampling points on the center line of the second vessel in the non-main coronary artery segment.

[0224] S1126. If the first sampling point and the second sampling point are located on different sides of the specified field of view based on the position data of the first sampling point, the position data of the second sampling point, and the normal vector of the specified field of view, the intersection of the line segment between the first sampling point and the second sampling point with the specified field of view is taken as the second intersection point.

[0225] S1128. Determine the specified pixel data corresponding to the line connecting the first intersection point and the second intersection point, and the distance between the first intersection point and the second intersection point.

[0226] S1130. Based on the specified pixel data, the pixel data at the first intersection point, the pixel data at the second intersection point, and the distance between the first and second intersection points, a separation evaluation is performed to obtain the separation evaluation data corresponding to the specified field of view.

[0227] Among them, the separation assessment data is used to describe the degree of separation between the main coronary artery segment and the non-main coronary artery segment.

[0228] S1132. Obtain the separation evaluation threshold.

[0229] S1134. Determine the location of the end sampling point corresponding to the separation evaluation data that is less than the separation evaluation threshold.

[0230] S1136. Determine the end position of the bifurcation based on the position of the end sampling point.

[0231] This specification provides a device 1200 for identifying the location of blood vessel bifurcation. Please refer to [link to relevant documentation]. Figure 12 The blood vessel bifurcation location identification device 1200 includes: a preliminary location data determination module 1210, a bifurcation start location determination module 1220, and a bifurcation end location determination module 1230.

[0232] The preliminary location data determination module 1210 is used to determine the preliminary location data of the bifurcation site of the blood vessel; wherein, the bifurcation site is used to indicate the bifurcation point of the branch blood vessel segment growing from the main blood vessel segment in the blood vessel tree;

[0233] The bifurcation start position determination module 1220 is used to calculate the minimum value of the distance between the main vessel segment and the branch vessel segment using the preliminary position data as a reference point, so as to obtain the bifurcation start position.

[0234] The bifurcation end position determination module 1230 is used to determine the bifurcation end position based on the separation assessment data between the main trunk segment and the branch segment; wherein, the separation assessment data is used to describe the degree of separation between the main trunk segment and the branch segment.

[0235] This specification provides a device 1300 for identifying the location of blood vessel bifurcation. Please refer to [link to relevant documentation]. Figure 13 The blood vessel bifurcation location identification device 1300 includes: an acquisition module 1310, a bifurcation start position determination module 1320, and a bifurcation end position determination module 1330.

[0236] The acquisition module 1310 is used to acquire a tissue image containing a vascular tree, wherein the vascular tree includes a first vascular segment and a second vascular segment;

[0237] The bifurcation start position determination module 1320 is used to obtain the bifurcation start positions of the first blood vessel segment and the second blood vessel segment based on the blood vessel centerline of the blood vessel tree.

[0238] The bifurcation end position determination module 1330 is used to obtain the bifurcation end positions of the first blood vessel segment and the second blood vessel segment based on the tissue image and the blood vessel centerline of the blood vessel tree.

[0239] For a detailed description of the device for identifying the location of blood vessel bifurcation, please refer to the description of the method for identifying the location of blood vessel bifurcation above, which will not be repeated here.

[0240] This specification provides a medical imaging device, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the method steps described above.

[0241] This specification provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method in any of the above embodiments.

[0242] One embodiment of this specification provides a computer program product including instructions that, when executed by a processor of a computer device, enable the computer device to perform the steps of the method described in any of the above embodiments.

[0243] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). In addition, computer-readable media can even be paper or other suitable media on which programs can be printed, because programs can be obtained electronically, for example, by optically scanning paper or other media, followed by editing, interpreting or otherwise processing as necessary, and then stored in computer memory.

Claims

1. A method for identifying the location of blood vessel bifurcation, characterized in that, The method includes: Acquire a tissue image containing a vascular tree, the vascular tree including a first vascular segment and a second vascular segment; Based on the vascular centerline of the vascular tree, the bifurcation start positions of the first vascular segment and the second vascular segment are obtained; Using the bifurcation start position as a reference point, multiple orthogonal visual planes are determined along the first vessel centerline of the first vessel segment, and the orthogonal visual planes are perpendicular to the first vessel centerline. Determine the first intersection point of the first vessel centerline of the first vessel segment with a designated field of view, and the second intersection point of the second vessel centerline of the second vessel segment with the designated field of view; wherein, the designated field of view is the orthogonal field of view corresponding to the separation evaluation data to be solved; Based on the tissue image, determine the specified pixel data corresponding to the line connecting the first intersection point and the second intersection point, the pixel data at the first intersection point, and the pixel data at the second intersection point; The separation evaluation data is determined based on the degree of difference between the specified pixel data and the pixel data at the first intersection point and the pixel data at the second intersection point; or, the separation evaluation data is determined based on the degree of difference between the specified pixel data and the pixel data at the first intersection point and the pixel data at the second intersection point, as well as the distance between the first intersection point and the second intersection point. The position corresponding to the orthogonal plane of the field of view that satisfies the separation evaluation threshold is determined as the bifurcation end position.

2. The method according to claim 1, characterized in that, The step of obtaining the bifurcation start position of the first blood vessel segment and the second blood vessel segment includes: Based on the blood vessel centerline, preliminary location data of the blood vessel bifurcation point are determined; Using the preliminary location data as a traversal reference point, the minimum value of the distance between the first blood vessel segment and the second blood vessel segment is calculated to obtain the bifurcation starting position.

3. The method according to claim 2, characterized in that, The vascular centerline includes the first vascular centerline of the first vascular segment and the second vascular centerline of the second vascular segment; the preliminary location data for determining the vascular bifurcation includes: Multiple main sampling points on the centerline of the first blood vessel and multiple designated branch sampling points on the centerline of the second blood vessel are determined; wherein, the multiple designated branch sampling points are a portion of the multiple branch sampling points on the centerline of the second blood vessel. Along the blood flow direction, the distance between the main trunk sampling point and the nearest branch sampling point is sequentially obtained. Based on the positions of the first branch sampling point with a distance greater than a first distance threshold and the corresponding main trunk sampling point, the preliminary position data is determined. The first distance threshold is determined by the maximum preset distance between the center line of the first blood vessel and the center line of the second blood vessel.

4. The method according to claim 2, characterized in that, The vascular centerline includes the first vascular centerline of the first vascular segment and the second vascular centerline of the second vascular segment; the step of using the preliminary position data as a traversal reference point to calculate the minimum value of the distance between the first vascular segment and the second vascular segment to obtain the bifurcation starting position includes: Along the opposite direction of blood flow, starting from the preliminary position data, the distance between the main sampling point of the first blood vessel centerline and the branch sampling point of the second blood vessel centerline is traversed to obtain the minimum distance value; The bifurcation starting position is obtained based on the branch sampling point and the main trunk sampling point corresponding to the first minimum distance value that is less than the third distance threshold; wherein, the third distance threshold is determined by the minimum preset distance between the center line of the first blood vessel and the center line of the second blood vessel.

5. The method according to claim 1, characterized in that, The specified pixel data is the minimum grayscale or CT value of the pixels traversed by the line connecting the first intersection point and the second intersection point.

6. The method according to claim 1, characterized in that, The second intersection point is determined in the following manner: Determine adjacent first and second sampling points on the center line of the second blood vessel segment in the second blood vessel segment; If the first sampling point and the second sampling point are located on different sides of the specified field of view based on the position data of the first sampling point, the position data of the second sampling point, and the normal vector of the specified field of view, the intersection of the line segment between the first sampling point and the second sampling point and the specified field of view is taken as the second intersection point.

7. The method according to any one of claims 1 to 6, characterized in that, The method further includes: Along the direction of blood flow, determine the starting and ending sampling points on the center line of multiple undetermined second vascular segments; For any of the undetermined second blood vessel segment, determine the initial closest distance between the starting sampling point and the center line of the first blood vessel segment, and the final closest distance between the ending sampling point and the end of the first blood vessel segment; The undetermined second vascular segment whose starting nearest distance is less than the fourth distance threshold and whose ending nearest distance is greater than the fourth distance threshold is determined as a branch vascular segment that originates from the first vascular segment.

8. A device for identifying the location of blood vessel bifurcation, characterized in that, The device includes: An acquisition module is used to acquire a tissue image containing a vascular tree, wherein the vascular tree includes a first vascular segment and a second vascular segment; The bifurcation start position determination module is used to obtain the bifurcation start positions of the first blood vessel segment and the second blood vessel segment based on the blood vessel centerline of the blood vessel tree. The bifurcation end position determination module is used to determine multiple orthogonal visual fields along the first vessel centerline of the first vessel segment, using the bifurcation start position as a reference point. These orthogonal visual fields are perpendicular to the first vessel centerline. The module determines the first intersection point of the first vessel centerline of the first vessel segment with a designated visual field plane, and the second intersection point of the second vessel centerline of the second vessel segment with the designated visual field plane. The designated visual field plane is the orthogonal visual field plane corresponding to the separation evaluation data to be solved. Based on the tissue image, the module determines designated pixel data corresponding to the line connecting the first and second intersection points, the pixel data at the first intersection point, and the pixel data at the second intersection point. The module determines the separation evaluation data based on the degree of difference between the designated pixel data and the pixel data at the first and second intersection points; or, based on the degree of difference between the designated pixel data and the pixel data at the first and second intersection points, and the distance between the first and second intersection points. The module determines the position corresponding to the orthogonal visual field plane where the separation evaluation data satisfies the separation evaluation threshold as the bifurcation end position.

9. A medical imaging device, comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 7.

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