Dynamic modeling method and apparatus for coronary artery, and device, medium, and program product

Abstract

The present application relates to a dynamic modeling method and apparatus for a coronary artery, and a device, a medium and a program product. The method comprises: constructing a vascular tree model of a target coronary artery (S101); on the basis of the vascular tree model, calculating the skin weight of the target coronary artery (S102); and tracking the centerline coordinates of the target coronary artery phase by phase, obtaining a plurality of key frames of the vascular tree model in view of the skin weight, and combining the plurality of key frames to obtain a dynamic sequence, so as to use the dynamic sequence to construct a dynamic model of the target coronary artery (S103). Therefore, the problems in the relevant art, such as it being impossible to obtain the time-varying 3D shape of a blood vessel, the accuracy and efficiency of CFD calculation performed at different moments and for mesh models having different topologies being low, and it being impossible to construct the intermediate shape of the blood vessel and corresponding numerical meshes when images are missing or are of poor quality, are solved.

Description

Method, device, equipment, medium and program product of dynamic modeling of coronary artery

[0001] Cross-reference to related applications

[0002] The present application claims priority to the Chinese patent application No. 202411007606.8, filed on July 25, 2024, with the title of "Method, device, equipment, medium and program product of dynamic modeling of coronary artery" and assigned to Tsinghua University. TECHNICAL FIELD

[0003] The present application relates to the field of medical and engineering cross technology, and in particular, relates to a method, device, equipment, medium and program product of dynamic modeling of coronary artery. BACKGROUND

[0004] Hemodynamic simulation can directly provide information about the time and spatial distribution of pressure and flow patterns within blood vessels, including not only wall shear stress oscillations, but also deformed shear stress distributions. The periodic nature of cardiac blood flow, the presence of branches, the separation and reconnection of blood flow, blood vessel motion, and the variable myocardial geometry within the cardiac cycle increase the complexity of blood flow patterns. Therefore, high-quality numerical grid partitioning is needed.

[0005] In the related art, in order to reflect the change of the geometric shape and embody the change of the numerical grid over time, MeshMorphing can be used in the CFD (Computational Fluid Dynamics) calculation process, by changing the numerical grid so that only the position of the boundary node changes, while the connection (connection matrix, topology) of the node and the element remains unchanged, thereby avoiding interpolation error between grids with different topologies; or based on the first point cloud data of the coronary artery reconstructed from multiple thoracic tomographic images collected, the coronary artery segment where the predicted position is located is determined, and then the cross section along the position of the center point in the coronary artery segment is generated to construct the second point cloud data, and the construction of the coronary artery is completed.

[0006] However, in the related art, the 3D shape of the blood vessel changing over time cannot be obtained, or the precision and efficiency of the CFD calculation of the grid model with inconsistent topologies at different time instants are low, and in addition, when images are lacking or the image quality is poor, the intermediate shape of the blood vessel and the corresponding numerical grid cannot be constructed, which needs to be improved.

[0007] SUMMARY

[0008] The application provides a method, device, equipment, medium and program product for dynamic modeling of coronary arteries, to solve the technical problems in the prior art that the 3D shape of blood vessels cannot be obtained over time, or the precision and efficiency of CFD calculation of the mesh model at different time instants are low, and in addition, the intermediate shape of the blood vessels and the corresponding numerical mesh cannot be constructed when images are lacking or the image quality is poor.

[0009] The first aspect of the application provides a method for dynamic modeling of coronary arteries, comprising the following steps: constructing a blood vessel tree model of a target coronary artery; calculating skinning weights of the target coronary artery based on the blood vessel tree model; tracking the centerline coordinates of the target coronary artery phase by phase, and obtaining a plurality of key frames of the blood vessel tree model in combination with the skinning weights, combining the plurality of key frames to obtain a dynamic sequence, and using the dynamic sequence to construct a dynamic model of the target coronary artery.

[0010] Optionally, in an embodiment of the application, the step of constructing the blood vessel tree model of the target coronary artery comprises: acquiring a preset image of the target coronary artery; reconstructing a three-dimensional surface model of the blood vessels of the target coronary artery based on the preset image; extracting the blood vessel centerline of the target coronary artery using the three-dimensional surface model of the blood vessels, and constructing the blood vessel tree model based on the blood vessel centerline.

[0011] Optionally, in an embodiment of the application, the step of calculating the skinning weights of the target coronary artery based on the blood vessel tree model comprises: determining the initial skinning weights of each vertex of the blood vessel tree model skeleton and the three-dimensional surface model of the blood vessels corresponding to the blood vessel centerline of the target coronary artery based on the blood vessel centerline; establishing a vertex group of the blood vessel tree model and the blood vessel tree model skeleton, so as to assign the vertices in the three-dimensional surface model of the blood vessels to the corresponding blood vessel tree model skeleton based on the vertex group; and calculating the skinning weights of each vertex relative to the blood vessel tree model skeleton using the initial skinning weights, the blood vessel tree model skeleton and a preset skinning weight formula, to obtain the skinning weights of the target coronary artery.

[0012] Optionally, in an embodiment of the application, the step of tracking the centerline coordinates of the target coronary artery phase by phase, and obtaining a plurality of key frames of the blood vessel tree model in combination with the skinning weights, combining the plurality of key frames to obtain a dynamic sequence, and using the dynamic sequence to construct a dynamic model of the target coronary artery comprises: tracking the centerline coordinates of the target coronary artery phase by phase to determine the pose of the blood vessel tree model skeleton in each key frame; obtaining the position of each vertex in each key frame according to the pose of the blood vessel tree model skeleton and the skinning weights; combining the plurality of key frames of all phases to obtain a dynamic sequence, and using the dynamic sequence to construct a dynamic model of the target coronary artery.

[0013] The second aspect embodiment of the present application provides a dynamic modeling device for coronary arteries, comprising: a construction module configured to construct a blood vessel tree model of a target coronary artery; a calculation module configured to calculate skinning weights of the target coronary artery based on the blood vessel tree model; and a generation module configured to track centerline coordinates of the target coronary artery phase by phase, and obtain a plurality of key frames of the blood vessel tree model in combination with the skinning weights, combine the plurality of key frames to obtain a dynamic sequence, and construct a dynamic model of the target coronary artery by using the dynamic sequence.

[0014] Optionally, in an embodiment of the present application, the construction module comprises: an acquisition unit configured to acquire a preset image of the target coronary artery; a reconstruction unit configured to reconstruct a three-dimensional blood vessel surface model of the target coronary artery based on the preset image; and a construction unit configured to extract a blood vessel centerline of the target coronary artery by using the three-dimensional blood vessel surface model, and construct the blood vessel tree model based on the blood vessel centerline.

[0015] Optionally, in an embodiment of the present application, the calculation module comprises: a first determination unit configured to determine initial skinning weights of each vertex of a blood vessel tree model skeleton and a three-dimensional blood vessel surface model corresponding to the blood vessel centerline of the target coronary artery; an establishment unit configured to establish a vertex group of the blood vessel tree model and the blood vessel tree model skeleton, so as to assign the vertices in the three-dimensional blood vessel surface model to corresponding blood vessel tree model skeletons based on the vertex group; and a calculation unit configured to calculate skinning weights of each vertex relative to the blood vessel tree model skeleton by using the initial skinning weights, the blood vessel tree model skeleton, and a preset skinning weight formula, so as to obtain the skinning weights of the target coronary artery.

[0016] Optionally, in an embodiment of the present application, the generation module comprises: a second determination unit configured to track the centerline coordinates of the target coronary artery phase by phase, so as to determine poses of the blood vessel tree model skeleton in each key frame; a first generation unit configured to obtain positions of each vertex in each key frame according to the poses of the blood vessel tree model skeleton and the skinning weights; and a second generation unit configured to combine the plurality of key frames of all phases to obtain a dynamic sequence, and construct a dynamic model of the target coronary artery by using the dynamic sequence.

[0017] The third aspect embodiment of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein the processor executes the program to implement the dynamic modeling method for coronary arteries as described in the above embodiments.

[0018] The fourth aspect of the present application provides a computer readable storage medium storing a computer program, which, when executed by a processor, implements the dynamic modeling method of the coronary artery as described above.

[0019] The fifth aspect of the present application provides a computer program product comprising a computer program, which, when executed, implements the dynamic modeling method of the coronary artery as described above.

[0020] The embodiments of the present application can calculate the skinning weight through the constructed blood vessel tree model of the target coronary artery, track the center line coordinates of the target coronary artery phase by phase, and use the skinning weight to generate a plurality of key frames of the blood vessel tree model to obtain a dynamic sequence, and then construct a dynamic model of the target coronary artery based on the dynamic sequence, generate a CFD grid with the same topology, avoid interpolation error between grids of different heart phases, and shorten the calculation time of hemodynamics. In addition, for dynamic tracking of the blood vessel tree model, even if the tracking of part of the blood vessels is lost at a certain phase, the adjacent frame data can be referred to to obtain a natural deformation effect of the target coronary artery. Thus, the technical problems in the related art that the 3D shape of the blood vessel cannot be obtained over time, or the precision and efficiency of the CFD calculation of the grid model with inconsistent topology at different time instants are low, and in addition, the intermediate shape of the blood vessel and the corresponding numerical grid cannot be constructed when the image is missing or the image quality is poor are solved.

[0021] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0022] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, including the accompanying drawings.

[0023] FIG. 1 is a flowchart of a dynamic modeling method of a coronary artery according to an embodiment of the present application;

[0024] FIG. 2 is a block diagram of the implementation effect of the dynamic modeling method of the coronary artery according to an embodiment of the present application;

[0025] FIG. 3 is a flowchart of extracting a blood vessel tree and an extraluminal section according to an embodiment of the present application;

[0026] FIG. 4 is a flowchart of calculating skinning weight using bounded biharmonic according to an embodiment of the present application;

[0027] FIG. 5 is a block diagram of the superimposed display effect of the dynamic coronary sequence according to an embodiment of the present application;

[0028] FIG. 6 is a flowchart of a method for constructing a dynamic model of a target coronary artery using a dynamic sequence according to an embodiment of the present application;

[0029] FIG. 7 is a flowchart of the working principle of a method for dynamic modeling of a coronary artery according to an embodiment of the present application;

[0030] FIG. 8 is a block diagram of a dynamic modeling device for a coronary artery according to an embodiment of the present application;

[0031] FIG. 9 is a structural diagram of an electronic device according to an embodiment of the present application.

[0032] Reference signs:

[0033] Wherein: 80 - a dynamic modeling device for a coronary artery; 100 - a construction module, 200 - a calculation module, 300 - a generation module; 901 - a memory, 902 - a processor, 903 - a communication interface. DETAILED DESCRIPTION

[0034] The embodiments of the present application are described in detail below with reference to the accompanying drawings, wherein the same or similar notations denote the same or similar elements throughout. The embodiments described below by reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as limiting the present application.

[0035] The dynamic modeling method, device, equipment, medium and program product for a coronary artery of the embodiments of the present application are described below with reference to the accompanying drawings. In view of the problems that the 3D shape of a blood vessel changing over time cannot be obtained, or the precision and efficiency of CFD calculation of a mesh model with inconsistent topology at different time instants are low, and in addition, the intermediate shape of a blood vessel and the corresponding numerical mesh cannot be constructed when images are missing or the image quality is poor, the present application provides a dynamic modeling method for a coronary artery. In the method, the skinning weight can be calculated based on a constructed blood vessel tree model of a target coronary artery, the centerline coordinates of the target coronary artery can be tracked phase by phase, and the skinning weight can be used to generate a plurality of key frames of the blood vessel tree model to obtain a dynamic sequence, and then a dynamic model of the target coronary artery is constructed based on the dynamic sequence, and by generating a CFD mesh with the same topology, interpolation errors between meshes at different heart phases are avoided, and the calculation time of hemodynamics is shortened. In addition, for dynamic tracking of the blood vessel tree model, even if the tracking of part of the blood vessels is lost at a certain phase, the adjacent frame data can be referred to to obtain a natural deformation effect of the target coronary artery. Thus, the problems that the 3D shape of a blood vessel changing over time cannot be obtained, or the precision and efficiency of CFD calculation of a mesh model with inconsistent topology at different time instants are low, and in addition, the intermediate shape of a blood vessel and the corresponding numerical mesh cannot be constructed when images are missing or the image quality is poor are solved.

[0036] Specifically, FIG. 1 is a flowchart of a method for dynamic modeling of a coronary artery according to an embodiment of the present application.

[0037] As shown in FIG. 1, the method for dynamic modeling of the coronary artery includes the following steps:

[0038] In step S101, a vessel tree model of a target coronary artery is constructed.

[0039] It can be understood that the vessel system formed by the target coronary artery and its branches is distributed in a "tree shape" on the surface of the heart, forming a complex vessel network, and therefore the vessel tree model of the target coronary artery can be constructed.

[0040] In some embodiments, the vessel tree model of the target coronary artery can be constructed by the embodiment of the present application, for example, the vessel tree model of the target coronary artery can be constructed by the angiography image at the end of diastole by the embodiment of the present application.

[0041] Further, it needs to be explained that at the end of diastole, the target coronary artery expands, the blood flow rate is relatively slow, and the development time of the contrast agent is short, which is beneficial to reduce artifacts and motion blur, so that the preset image has a higher definition.

[0042] Optionally, in an embodiment of the present application, the vessel tree model of the target coronary artery is constructed, including: obtaining a preset image of the target coronary artery; reconstructing a three-dimensional vessel surface model of the target coronary artery based on the preset image; extracting a vessel centerline of the target coronary artery using the three-dimensional vessel surface model, and constructing a vessel tree model based on the vessel centerline.

[0043] It can be understood that the embodiment of the present application can use medical imaging means such as CTA (Computed Tomography Angiography, CT angiography), magnetic resonance angiography, intravascular ultrasound, etc., and the present application does not make specific limitations to obtain the preset image of the target coronary artery.

[0044] For example, the embodiment of the present application takes the CTA image as an example for illustration, specifically, the embodiment of the present application can use the preset image of the target coronary artery of the CTA scan of the ECG (Electrocardiogram, electrocardiogram) gating.

[0045] In combination with the above, the embodiment of the present application can reconstruct the three-dimensional vessel surface model and the vessel tree model of the target coronary artery based on the CTA image at the end of diastole.

[0046] As a possible implementation manner, the embodiment of the present application can reconstruct a three-dimensional surface model of a target coronary artery based on a preset image of the target coronary artery, and extract a vessel centerline of the target coronary artery by using the three-dimensional surface model of the vessel to construct a vessel tree model.

[0047] In the embodiment of the present application, the vessel centerline is defined as a weighted shortest path between two end points. The extraction of the vessel centerline can be performed on a Voronoi diagram of the three-dimensional surface model of the vessel, which defines the centers of the largest inscribed spheres. The vessel centerline is determined as a path defined on the Voronoi diagram that minimizes the integral of the largest inscribed sphere radius along the path, which is equivalent to finding the shortest path in the radius metric. Further, in the embodiment of the present application, there are various methods for extracting the vessel centerline, which are not specifically limited in the present application.

[0048] For example, as shown in FIG. 2, the embodiment of the present application can obtain a CTA image at the end diastole as shown in FIG. 2(a), wherein FIG. 2(a) is a block schematic diagram of the CTA image at the end diastole according to an embodiment of the present application.

[0049] Further, the embodiment of the present application separates the target coronary artery from the surrounding tissues and vessels by using a segmentation algorithm to obtain the segmented target coronary artery, and reconstructs a three-dimensional surface model of the vessel of the target coronary artery as shown in FIG. 2(b), wherein FIG. 2(b) is a block schematic diagram of the three-dimensional surface model of the vessel of the target coronary artery according to an embodiment of the present application.

[0050] Further, the embodiment of the present application can extract a vessel centerline of the target coronary artery by using a skeleton extraction algorithm based on the three-dimensional surface model of the vessel to construct a vessel tree model as shown in FIG. 2(c), wherein FIG. 2(c) is a block schematic diagram of the constructed vessel tree model of the target coronary artery according to an embodiment of the present application.

[0051] In the embodiment of the present application, a method based on bidirectional minimum path propagation can be used to automatically extract the vessel tree and the extraluminal cross section, and the main flow is shown in FIG. 3, which can be as follows:

[0052] Step S301: Extract and optimize an initial path of a vessel.

[0053] That is, the embodiment of the present application can extract an initial path of a vessel, and optimize the initial path according to the path curvature, Laplace filtering and Dijkstra algorithm to obtain a corresponding optimal path, or other algorithms can be selected for optimization, which are not specifically limited in the present application.

[0054] Step S302: Generate a vessel centerline.

[0055] That is, the embodiment of the present application can use the iterative optimization algorithm based on the cubic spline interpolation algorithm to generate a blood vessel centerline by dynamically interpolating the optimal path obtained in step S301, and can also use other algorithms to generate a blood vessel centerline, which is not specifically limited in the present application.

[0056] Step S303: generating a plurality of blood vessel centerlines.

[0057] That is, the embodiment of the present application can obtain a plurality of blood vessel centerlines by repeating steps S301 and S302 several times.

[0058] Step S304: obtaining a blood vessel tree.

[0059] That is, the embodiment of the present application can combine the plurality of blood vessel centerlines in step S303 into a blood vessel tree.

[0060] Step S305: obtaining a more accurate blood vessel tree.

[0061] That is, the embodiment of the present application can optimize the blood vessel tree in step S304 using an evolution method based on the Open-Snake model to obtain a more accurate blood vessel tree. Wherein, the Open-Snake of the embodiment of the present application is a dynamic contour model for extracting a centerline, which is driven by two external forces of gradient vector flow and adaptive stretching force acting on both ends of the open curve, which can optimize each blood vessel centerline in the blood vessel tree. Other optimization methods can also be used, which are not specifically limited in the present application.

[0062] Step S306: generating an extraluminal cross section of the blood vessel.

[0063] That is, the embodiment of the present application can generate a series of extraluminal cross sections along the blood vessel centerline through the two-dimensional cross section of the blood vessel.

[0064] In step S102, the skinning weight of the target coronary artery is calculated based on the blood vessel tree model.

[0065] In some embodiments, the embodiment of the present application can calculate the skinning weight of the target coronary artery based on the blood vessel tree model.

[0066] It can be understood that in the skeletal animation of the three-dimensional surface model, the skinning weight can refer to the influence degree between each vertex and the skeleton, which can determine how the vertex follows the action of the skeleton during the animation process. In the field of computational geometry, bounded biharmonic weight as a kind of skinning weight is usually used in the parameterization process of surface reconstruction and subdivision surface, which can obtain smoother and more accurate surface results.

[0067] Optionally, in an embodiment of the present application, the skinning weight of the target coronary artery is calculated based on the vessel tree model, including: determining the initial skinning weight of each vertex of the vessel three-dimensional surface model corresponding to the vessel tree model skeleton and the vessel centerline based on the vessel centerline of the target coronary artery; establishing a vertex group of the vessel tree model and the vessel tree model skeleton, so as to assign the vertex in the vessel three-dimensional surface model to the corresponding vessel tree model skeleton based on the vertex group; and calculating the skinning weight of each vertex relative to the vessel tree model skeleton by using the initial skinning weight, the vessel tree model skeleton and a preset skinning weight formula, so as to obtain the skinning weight of the target coronary artery.

[0068] In actual implementation, in an embodiment of the present application, the initial skinning weight of each vertex of the vessel three-dimensional surface model corresponding to the vessel tree model skeleton and the vessel centerline can be determined based on the vessel centerline of the target coronary artery, the vertex in the vessel three-dimensional surface model can be assigned to the corresponding skeleton based on the vertex group of the vessel tree model and the vessel tree model skeleton, and further, the skinning weight of each vertex can be calculated by using a certain skinning weight formula, so as to obtain the skinning weight of the target coronary artery.

[0069] For example, in an embodiment of the present application, the skinning weight is calculated by using the bounded biharmonic, and the main process is shown in FIG. 4, which can be as follows:

[0070] Step S401: determining the skeleton of the vessel tree model and the initial skinning weight of each vertex in the skeleton.

[0071] It can be understood that, in an embodiment of the present application, the vessel centerline of the target coronary artery can be taken as the skeleton of the vessel tree model, and the initial skinning weight of each vertex of the vessel three-dimensional surface model corresponding to the vessel centerline can be determined.

[0072] Step S402: establishing a vertex group of the vessel tree model and the vessel tree model skeleton.

[0073] It can be understood that, in an embodiment of the present application, the vessel tree model can be discretized to disperse the surface of the vessel tree model into surface vertices, a vertex group corresponding to the skeleton is established, and the vertices in the group are assigned to the corresponding skeleton.

[0074] Step S403: calculating the weight between the vertex and the neighborhood vertex.

[0075] It can be understood that, in an embodiment of the present application, for each vertex v i , its neighborhood vertex set N(i) is found, and the weight ω i,j between the vertex v i and the neighborhood vertex v j is calculated.

[0076] Step S404: calculating the bounded biharmonic weight of the vertex.

[0077] It can be understood that the embodiment of the application can calculate the bounded biharmonic weight ω i of the vertex v i , and the calculation formula can be but is not limited to:

[0078] wherein ω j is the initial skinning weight of the vertex v j .

[0079] Step S405: converging the bounded biharmonic weight.

[0080] It can be understood that the embodiment of the application can repeatedly execute step S404 until the bounded biharmonic weight ω i converges. Wherein the embodiment of the application can use the conjugate gradient method or the like to solve, and the application does not make specific limitations.

[0081] Step S406: calculating the skinning weight.

[0082] It can be understood that the embodiment of the application can calculate the skinning weight of each target coronary artery bone through a certain skinning weight formula. For the bone k, its skinning weight ω i,k can be calculated through a certain skinning weight formula, and its expression can be but is not limited to:

[0083] wherein ω j,k represents the skinning weight of the vertex v j relative to the bone k.

[0084] Step S407: skinning weight normalization.

[0085] It can be understood that the embodiment of the application can normalize the skinning weight ω i , ω i,1 , …, ω i,2 of each vertex v i,k so that their sum is equal to 1.

[0086] As shown in FIG. 5, the embodiment of the application can use the blood vessel centerline as the bone of the blood vessel tree model, and calculate the skinning weight of the blood vessel tree model using the bounded biharmonic weight.

[0087] In step S103, the centerline coordinates of the target coronary artery are tracked phase by phase, and the skinning weight is combined to obtain a plurality of key frames of the blood vessel tree model, and the plurality of key frames are combined to obtain a dynamic sequence, so as to construct a dynamic model of the target coronary artery using the dynamic sequence.

[0088] In some embodiments, the embodiments of the present application can track the centerline coordinates of the target coronary artery phase by phase, and generate a plurality of key frames of the blood vessel tree model using skinning weights, and then obtain a dynamic sequence of the target coronary artery, and construct a dynamic model of the target coronary artery.

[0089] In the embodiments of the present application, the key frame can be used to describe a snapshot of the state of the blood vessel tree model at a certain phase, which can include but is not limited to the position, posture, filling condition, etc. of each branch of the target coronary artery, and the present application does not make specific limitations. In addition, the key frame of the embodiments of the present application can take time as the axis, and then the state of the blood vessel tree model at different time points can be determined.

[0090] Optionally, in one embodiment of the present application, the centerline coordinates of the target coronary artery are tracked phase by phase, and a plurality of key frames of the blood vessel tree model are obtained in combination with the skinning weights, the plurality of key frames are combined to obtain a dynamic sequence, and the dynamic sequence is used to construct a dynamic model of the target coronary artery, including: tracking the centerline coordinates of the target coronary artery phase by phase to determine the posture of the blood vessel tree model skeleton in each key frame; obtaining the position of each vertex in each key frame according to the posture of the blood vessel tree model skeleton and the skinning weight; combining the plurality of key frames of all phases to obtain a dynamic sequence, and using the dynamic sequence to construct a dynamic model of the target coronary artery.

[0091] As a possible implementation manner, the embodiments of the present application can track the centerline coordinates of the target coronary artery phase by phase, determine the posture of the blood vessel tree model skeleton in each key frame, and then the embodiments of the present application can obtain the position of each vertex in each key frame according to the posture of the blood vessel tree model skeleton and the skinning weight, and obtain a dynamic sequence by combining the plurality of key frames of all phases, and then construct a dynamic model of the target coronary artery.

[0092] For example, the main process of constructing a dynamic model of the target coronary artery using a dynamic sequence according to the embodiments of the present application is shown in FIG. 6, which can be as follows:

[0093] Step S601: determining the posture of the blood vessel tree model skeleton in each key frame.

[0094] It can be understood that in each key frame, the embodiments of the present application can set the posture of the skeleton according to the image information of the corresponding phase. In the embodiments of the present application, for each skeleton, the overall posture of the blood vessel tree model can be defined according to the rotation, translation, etc. in the key frame.

[0095] Step S602: determining the position of each vertex in each key frame.

[0096] It can be understood that the embodiment of the application can calculate the position of each vertex in each key frame. For each key frame, the position of each vertex relative to the skeleton needs to be calculated, that is, the position of each vertex in the key frame is calculated through the skinning weight.

[0097] Step S603: combine the plurality of key frames of all phases.

[0098] It can be understood that the embodiment of the application can connect the key frames, connect the plurality of key frames of all phases in time sequence, generate a complete dynamic sequence, and construct a dynamic model of the target coronary artery by using the dynamic sequence.

[0099] The working principle of the coronary artery dynamic modeling method proposed in the embodiment of the application will be described in detail below in combination with a specific embodiment.

[0100] FIG. 7 is a flowchart of the working principle of the coronary artery dynamic modeling method according to an embodiment of the application.

[0101] Step S701: construct a blood vessel tree model of the target coronary artery based on the CTA image at end diastole.

[0102] It can be understood that the embodiment of the application can separate the target coronary artery in the CTA image at end diastole as shown in FIG. 2(a) from the surrounding tissues and blood vessels by using a segmentation algorithm as shown in FIG. 2, obtain the segmented target coronary artery, reconstruct the three-dimensional surface model of the target coronary artery as shown in FIG. 2(b), and then extract the blood vessel centerline of the target coronary artery based on the three-dimensional surface model of the blood vessel by using a skeleton extraction algorithm, and construct the blood vessel tree model as shown in FIG. 2(c).

[0103] Step S702: calculate the skinning weight based on the blood vessel tree model.

[0104] It can be understood that the embodiment of the application can use the bounded biharmonic to calculate the skinning weight as shown in FIG. 4, and then obtain the effect diagram as shown in FIG. 5.

[0105] Step S703: track the skeleton centerline phase by phase, generate the key frame of the blood vessel tree model by using the skinning weight, obtain the dynamic sequence of the blood vessel tree model, and construct the dynamic model of the target coronary artery.

[0106] It can be understood that the embodiment of the application can construct the dynamic model of the target coronary artery by using the dynamic sequence as shown in FIG. 6.

[0107] According to the dynamic modeling method of the coronary artery provided in the embodiments of the present application, the skinning weight of the target coronary artery can be calculated by the constructed blood vessel tree model, the center line coordinates of the target coronary artery are tracked phase by phase, and the skinning weight is used to generate a plurality of key frames of the blood vessel tree model to obtain a dynamic sequence, and then a dynamic model of the target coronary artery is constructed based on the dynamic sequence, the CFD grid with the same topology is generated, the interpolation error between the grids of different heart phases is avoided, and the calculation time of the blood flow dynamics is shortened. In addition, for the dynamic tracking of the blood vessel tree model, even if the tracking of part of the blood vessels is lost at a certain phase, the adjacent frame data can be referred to to obtain a transition natural deformation effect of the target coronary artery. Thus, the technical problems in the related art that the 3D shape of the blood vessel cannot be obtained over time, or the precision and efficiency of the CFD calculation of the grid model with inconsistent topologies at different time instants are low, and in addition, the intermediate shape of the blood vessel and the corresponding numerical grid cannot be obtained when the image is missing or the image quality is poor are solved.

[0108] Secondly, the dynamic modeling device of the coronary artery provided in the embodiments of the present application is described with reference to the accompanying drawings.

[0109] FIG. 8 is a block schematic diagram of the dynamic modeling device of the coronary artery provided in the embodiments of the present application.

[0110] As shown in FIG. 8, the dynamic modeling device 80 of the coronary artery includes a construction module 100, a calculation module 200 and a generation module 300.

[0111] The construction module 100 is configured to construct a blood vessel tree model of a target coronary artery.

[0112] The calculation module 200 is configured to calculate a skinning weight of the target coronary artery based on the blood vessel tree model.

[0113] The generation module 300 is configured to track the center line coordinates of the target coronary artery phase by phase, and obtain a plurality of key frames of the blood vessel tree model in combination with the skinning weight, combine the plurality of key frames to obtain a dynamic sequence, and construct a dynamic model of the target coronary artery by using the dynamic sequence.

[0114] Optionally, in an embodiment of the present application, the construction module 100 includes an acquisition unit, a reconstruction unit and a construction unit.

[0115] The acquisition unit is configured to acquire a preset image of the target coronary artery.

[0116] The reconstruction unit is configured to reconstruct a three-dimensional surface model of the blood vessel of the target coronary artery based on the preset image.

[0117] The construction unit is configured to extract the blood vessel center line of the target coronary artery by using the three-dimensional surface model of the blood vessel, and construct the blood vessel tree model based on the blood vessel center line.

[0118] Optionally, in an embodiment of the present application, the calculating module 200 comprises a first determining unit, a establishing unit and a calculating unit.

[0119] The first determining unit is configured to determine initial skinning weights of each vertex of the three-dimensional surface model of the blood vessel corresponding to the blood vessel skeleton of the target coronary artery based on the blood vessel centerline of the target coronary artery.

[0120] The establishing unit is configured to establish a vertex group of the blood vessel tree model and the blood vessel skeleton, and assign the vertices in the three-dimensional surface model of the blood vessel to the corresponding blood vessel skeleton based on the vertex group.

[0121] The calculating unit is configured to calculate the skinning weights of each vertex relative to the blood vessel skeleton by using the initial skinning weights, the blood vessel skeleton and a preset skinning weight formula, so as to obtain the skinning weights of the target coronary artery.

[0122] Optionally, in an embodiment of the present application, the generating module 300 comprises a second determining unit, a first generating unit and a second generating unit.

[0123] The second determining unit is configured to track the centerline coordinates of the target coronary artery phase by phase, so as to determine the pose of the blood vessel skeleton in each key frame.

[0124] The first generating unit is configured to obtain the position of each vertex in each key frame according to the pose and the skinning weights of the blood vessel skeleton.

[0125] The second generating unit is configured to combine the plurality of key frames of all phases to obtain a dynamic sequence, and construct a dynamic model of the target coronary artery by using the dynamic sequence.

[0126] It should be noted that the above-mentioned explanation of the embodiment of the dynamic modeling method of the coronary artery is also applicable to the dynamic modeling device of the coronary artery of the embodiment, which will not be described here.

[0127] According to the dynamic modeling device for coronary arteries provided in the embodiments of the present application, the skinning weight can be calculated through the constructed blood vessel tree model of the target coronary artery, the center line coordinates of the target coronary artery are tracked phase by phase, and the skinning weight is used to generate a plurality of key frames of the blood vessel tree model to obtain a dynamic sequence, and then a dynamic model of the target coronary artery is constructed based on the dynamic sequence, the CFD grid with the same topology is generated, the interpolation error between the grids of different heart phases is avoided, and the calculation time of the blood flow dynamics is shortened. In addition, for the dynamic tracking of the blood vessel tree model, even if the tracking of part of the blood vessels is lost at a certain phase, the adjacent frame data can be referred to to obtain a natural deformation effect of the target coronary artery. Thus, the technical problems in the related art that the 3D shape of the blood vessel cannot be obtained over time, or the precision and efficiency of the CFD calculation of the grid model with inconsistent topology at different time instants are low, and in addition, the intermediate shape of the blood vessel and the corresponding numerical grid cannot be constructed when the image is missing or the image quality is poor are solved.

[0128] Fig. 9 is a structural schematic diagram of an electronic device provided by the embodiments of the present application. The electronic device can include:

[0129] The memory 901, the processor 902 and the computer program stored in the memory 901 and executable on the processor 902.

[0130] The processor 902 implements the dynamic modeling method for coronary arteries provided in the above embodiments when executing the program.

[0131] Further, the electronic device further includes:

[0132] The communication interface 903 is used for communication between the memory 901 and the processor 902.

[0133] The memory 901 is used to store the computer program executable on the processor 902.

[0134] The memory 901 can include a high-speed RAM memory, and can also include a non-volatile memory such as at least one disk memory.

[0135] If the memory 901, the processor 902 and the communication interface 903 are implemented independently, the communication interface 903, the memory 901 and the processor 902 can be connected with each other through a bus and complete communication between each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the convenience of representation, only one thick line is used in FIG. 9, but it does not mean that there is only one bus or only one type of bus.

[0136] Optionally, in a specific implementation, if the memory 901, the processor 902 and the communication interface 903 are integrated on a chip, the memory 901, the processor 902 and the communication interface 903 can complete communication between each other through an internal interface.

[0137] The processor 902 can be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement one or more embodiments of the present application.

[0138] The embodiments of the present application also provide a computer readable storage medium, which stores a computer program. The program is executed by a processor to implement the dynamic modeling method of the coronary artery.

[0139] The embodiments of the present application also provide a computer program product, which includes a computer program. The program is executed to implement the dynamic modeling method of the coronary artery.

[0140] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example" or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the present application and the features of the different embodiments or examples without contradiction.

[0141] Furthermore, the terms "first", "second", etc. are used herein only to describe different instances, and do not imply or suggest relative importance or a number of the indicated technical features. Thus, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "N" is at least two, for example, two, three, etc., unless otherwise explicitly and specifically limited.

[0142] Any process or method descriptions or descriptions of the flow diagrams herein, or otherwise described herein, can be understood as representing the steps of a method implemented by a computer or a processor, or otherwise embodied in computer-readable or computer-usable code instructions, or other instructions, or a combination thereof, and the scope of the preferred embodiments of the present application includes additional implementation involving the use of one or more computers or processors, or other instructions, or a combination thereof, in which the functions described can be implemented by one or more computers or processors, or other instructions, or a combination thereof, in different order, or with additional functions, or with different functions, or with different degrees of parallelism, or with different combinations of parallelism and sequential execution, or with other additional implementation, as will be understood by those skilled in the art.

[0143] The logic and / or steps represented in the flow diagrams, or otherwise described herein, for example, can be considered as a list of executable instructions for implementing the logic function, and can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor- based system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device, and execute the instructions, or in conjunction with which the instructions can be executed. For purposes of this specification, a "computer-readable medium" can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium include the following: an electrical connection having one or more wires (electrical apparatus), a portable computer diskette (magnetic apparatus), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber (optical apparatus), and a portable compact disc read-only memory (CDROM). In addition, the computer-readable medium can even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via the optical scan of the paper or other medium, then compiled, interpreted, or otherwise processed in a suitable manner, if necessary, and then stored in the computer memory.

[0144] It should be understood that portions of the application can be realized with a combination of hardware, software, firmware, or their combination. In the above-described embodiments, the N steps or methods can be realized with software or firmware stored in a memory and executed by a suitable instruction execution system. If realized with hardware and in another embodiment, it can be realized with any one or a combination of the following technologies known in the art: discrete logic circuit with logic gate circuit for implementing logic functions on data signals, application specific integrated circuit with suitable combination logic gate circuit, programmable gate array (PGA), field programmable gate array (FPGA), etc.

[0145] Those skilled in the art of the present technology can understand that all or part of the steps carried out by the above-mentioned embodiments can be completed by a program instructing the relevant hardware, and the program can be stored in a computer readable storage medium. When the program is executed, it includes one of the steps of the method embodiments or a combination thereof.

[0146] In addition, the functional units in each embodiment of the present application can be integrated into one processing module, or each unit can exist physically alone, or two or more units can be integrated into one module. The integrated module can be realized in the form of hardware or in the form of a software functional module. The integrated module, if realized in the form of a software functional module and sold or used as an independent product, can also be stored in a computer readable storage medium.

[0147] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it should be understood that the above-mentioned embodiments are exemplary and cannot be understood as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-mentioned embodiments within the scope of the present application.

Claims

A method of dynamic modeling of a coronary artery, characterized by The method comprises the following steps: constructing a blood vessel tree model of a target coronary artery; calculating skinning weights of the target coronary artery based on the blood vessel tree model; tracking centerline coordinates of the target coronary artery phase by phase, and obtaining a plurality of key frames of the blood vessel tree model in combination with the skinning weights, combining the plurality of key frames to obtain a dynamic sequence, and constructing a dynamic model of the target coronary artery by using the dynamic sequence. The method of dynamic modeling of coronary arteries according to claim 1, characterized in that, The constructing the blood vessel tree model of the target coronary artery comprises: acquiring preset images of the target coronary artery; reconstructing a blood vessel three-dimensional surface model of the target coronary artery based on the preset images; extracting a blood vessel centerline of the target coronary artery by using the blood vessel three-dimensional surface model, and constructing the blood vessel tree model based on the blood vessel centerline. The method of dynamic modeling of coronary arteries according to claim 1, characterized in that, The calculating the skinning weights of the target coronary artery based on the blood vessel tree model comprises: determining initial skinning weights of each vertex of a blood vessel three-dimensional surface model corresponding to a blood vessel tree model skeleton and the blood vessel centerline based on the blood vessel centerline of the target coronary artery; establishing a vertex group of the blood vessel tree model and the blood vessel tree model skeleton, so as to assign the vertices in the blood vessel three-dimensional surface model to corresponding blood vessel tree model skeletons based on the vertex group; calculating skinning weights of each vertex relative to the blood vessel tree model skeleton by using the initial skinning weights, the blood vessel tree model skeleton and a preset skinning weight formula, so as to obtain the skinning weights of the target coronary artery. The method of dynamic modeling of coronary arteries according to claim 1, characterized in that, The tracking the centerline coordinates of the target coronary artery phase by phase, and obtaining the plurality of key frames of the blood vessel tree model in combination with the skinning weights, combining the plurality of key frames to obtain the dynamic sequence, and constructing the dynamic model of the target coronary artery by using the dynamic sequence comprises: tracking the centerline coordinates of the target coronary artery phase by phase, so as to determine poses of the blood vessel tree model skeleton in each key frame; obtaining positions of each vertex in each key frame according to the poses of the blood vessel tree model skeleton and the skinning weights; combining the plurality of key frames of all phases to obtain a dynamic sequence, and constructing the dynamic model of the target coronary artery by using the dynamic sequence. A device for dynamic modeling of coronary arteries, characterized by The method comprises: a constructing module, configured to construct a blood vessel tree model of a target coronary artery; a calculating module, configured to calculate skinning weights of the target coronary artery based on the blood vessel tree model; a generating module, configured to track centerline coordinates of the target coronary artery phase by phase, and obtain a plurality of key frames of the blood vessel tree model in combination with the skinning weights, combine the plurality of key frames to obtain a dynamic sequence, and construct a dynamic model of the target coronary artery by using the dynamic sequence. The dynamic modeling device of the coronary artery according to claim 5, characterized in that, The constructing module comprises: an acquiring unit, configured to acquire preset images of the target coronary artery; a reconstructing unit, configured to reconstruct a blood vessel three-dimensional surface model of the target coronary artery based on the preset images; a constructing unit, configured to extract a blood vessel centerline of the target coronary artery by using the blood vessel three-dimensional surface model, and construct the blood vessel tree model based on the blood vessel centerline. The dynamic modeling device of the coronary artery according to claim 5, characterized in that, The calculating module comprises: The first determining unit is configured to determine a blood vessel tree model skeleton and initial skinning weights of each vertex of a blood vessel three-dimensional surface model corresponding to the blood vessel centerline of the target coronary artery based on the blood vessel centerline of the target coronary artery; The establishing unit is configured to establish a vertex group of the blood vessel tree model and the blood vessel tree model skeleton, and assign the vertices in the blood vessel three-dimensional surface model to corresponding blood vessel tree model skeletons based on the vertex group; The calculating unit is configured to calculate skinning weights of each vertex relative to the blood vessel tree model skeleton by using the initial skinning weights, the blood vessel tree model skeleton and a preset skinning weight formula, to obtain skinning weights of the target coronary artery. The dynamic modeling device of the coronary artery according to claim 5, characterized in that, The generation module comprises: The second determining unit is configured to track centerline coordinates of the target coronary artery phase by phase to determine poses of the blood vessel tree model skeleton in each key frame; The first generation unit is configured to obtain positions of each vertex in each key frame according to the poses of the blood vessel tree model skeleton and the skinning weights; The second generation unit is configured to combine a plurality of key frames of all phases to obtain a dynamic sequence, and construct a dynamic model of the target coronary artery by using the dynamic sequence. An electronic device, characterized by The computer program is executed by the processor to implement the dynamic modeling method of the coronary artery according to any one of claims 1-4. The program is executed by the processor to implement the dynamic modeling method of the coronary artery according to any one of claims 1-4. A computer-readable storage medium having stored thereon a computer program, characterized in that The computer program is executed to implement the dynamic modeling method of the coronary artery according to any one of claims 1-4. ​ A computer program product, characterized in that ​

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