A method and system for three-dimensional cardiac modeling based on three-dimensional cardiac mapping

Abstract

The present invention provides a method and system for three-dimensional cardiac modeling based on three-dimensional cardiac mapping, comprising: MRI modeling of a target heart; obtaining a local endocardial model; translating, rotating and scaling the MRI three-dimensional endocardial model so that the local endocardial model overlaps with the endocardium of the MRI three-dimensional endocardial model; obtaining a first slicing line segment and a second slicing line segment; calculating the similarity of the first slicing line segment and the second slicing line segment; when the similarity of the first slicing line segment and the second slicing line segment is less than a first threshold, displaying a point to be mapped at the middle position of the first slicing line segment and the second slicing line segment; using a mapping catheter to map the point to be mapped and obtaining the position data of the point to be mapped; and correcting the MRI three-dimensional endocardial model according to the position data of the point to be mapped and the first slicing line segment and the second slicing line segment. The above scheme improves the accuracy of the model.

Description

Technical Field

[0001] The present invention relates to the field of medical data processing, and in particular to a method and system for three-dimensional cardiac modeling based on three-dimensional cardiac mapping. Background Art

[0002] There are many technologies for three-dimensional modeling of the heart, such as cardiac mapping technology, echocardiography, magnetic resonance imaging (MRI), etc.

[0003] Magnetic resonance imaging technology is the most widely used three-dimensional imaging technology for human organs in existing technologies because of its better imaging effect on soft tissues. Magnetic resonance imaging technology based on MRI requires an MRI scan first. Each MRI scan will produce hundreds or thousands of slices, which can be observed in different directions (such as sagittal, coronal and axial). If the slices are too fine, the amount of calculation for three-dimensional modeling will increase dramatically. Therefore, the distance between slices is usually 0.3-0.5cm. After obtaining the slices, the unknown data between the slices also need to be interpolated and supplemented to obtain a complete three-dimensional model of the heart. Magnetic resonance imaging technology has the problem that the complete endocardial surface obtained by interpolation method usually has a certain error.

[0004] The basic principle of mapping technology is to place three pairs of electrodes with orthogonal spatial positions on the patient's body surface. The usual positions are the front chest-back, left armpit-right armpit, and back of the neck-inner thigh. These three pairs of electrodes form a three-dimensional space in space, similar to the xyz three-axis of three-dimensional coordinates. When performing mapping, the catheter is sent to the heart through the thigh vein, and the catheter head has a device for collecting ECG signals. When performing mapping, the physician operates the catheter head to move forward, backward, bend, and rotate so that the catheter head can touch the heart's endothelium and determine the position of the catheter head in the coordinate system formed by the three pairs of electrodes. After obtaining the positions of multiple endothelium, the unmeasured positions can be interpolated through triangulation and other technologies to obtain the completed endothelium surface. Due to the limited position of the actual measured data points and the large variation range of the endothelium surface, the complete endothelium surface obtained by the interpolation method usually has a certain error. In addition, the risk factor of mapping surgery is high, and it is usually performed simultaneously with other diagnostic and treatment processes. The operation time is tight, and too much time cannot be used for mapping. The biggest advantage of mapping technology is that it is the most accurate test for a specific location and can provide more detailed measurements of the lesion location. Summary of the invention

[0005] In order to solve the problem of inaccurate modeling of a single MRI method in the prior art, the present invention provides a method and system for three-dimensional cardiac modeling based on three-dimensional cardiac mapping.

[0006] In one aspect of the present invention, a method for three-dimensional modeling of a heart based on three-dimensional mapping of the heart is provided, characterized in that the method comprises the following steps: performing MRI modeling on a target heart to obtain an MRI three-dimensional endocardial model and corresponding MRI slice data; performing preliminary mapping on the target heart to obtain a local endocardial model; taking the local endocardial model as a reference, translating, rotating and scaling the MRI three-dimensional endocardial model so that the local endocardial model overlaps with the endocardium of the MRI three-dimensional endocardial model; obtaining a first slice line segment and a second slice line segment according to the MRI three-dimensional endocardial model, the MRI slice data and a first spatial window, the slice line segment being an intersection line between an MRI slice and the MRI three-dimensional endocardial model, the first slice line segment and the second slice line segment being two adjacent slice line segments; calculating the similarity between the first slice line segment and the second slice line segment; When the similarity between the first slicing line segment and the second slicing line segment is less than a first threshold, a point to be marked is displayed in the middle position between the first slicing line segment and the second slicing line segment; the point to be marked is marked using a marking catheter to obtain position data of the point to be marked; and the MRI three-dimensional endothelial model is corrected according to the position data of the point to be marked and the first slicing line segment and the second slicing line segment.

[0007] The MRI three-dimensional endothelial model is segmented by using the segmentation function. The image segmentation function is expressed as:

[0008]

[0009]

[0010]

[0011] in, represents the positioning function, Represents the horizontal coordinate of the image pixel. Indicates the direction of the horizontal coordinate of the image pixel point, Represents the vertical coordinate of the image pixel. represents the image noise coefficient, represents the Gaussian white noise of the image, Indicates the size of the MRI three-dimensional endothelium, m represents the number of MRI slices, Indicates the size of the image after segmentation is completed. Represents the number of image segmentation targets, Represents the grayscale value of the image, represents the image segmentation speed, represents the tube side of the three-dimensional image, j Represents a constant, which is related to the image clarity. Represents the intimal overlap rate of the MRI three-dimensional intimal model.

[0012] The present invention segments the MRI image through the image segmentation function, so that the segmented image is easier to process subsequently. The establishment of the function involves image pixels, image noise, MRI slice number, image grayscale value, etc. By fusing these variables, the segmented image is more convenient to process. The function is based on existing theories, is simple and easy to understand, and can effectively improve the accuracy of three-dimensional coordinate modeling of the heart.

[0013] Furthermore, the first spatial window is a cuboid in the local endothelial model coordinate system, and the cuboid moves in the MRI three-dimensional endothelial model coordinate system with a first step length.

[0014] Furthermore, acquiring the first slice line segment and the second slice line segment according to the MRI three-dimensional endothelial model, the MRI slice data and the first spatial window includes: obtaining an intersection curve of the MRI three-dimensional endothelial model and the MRI slice according to the MRI three-dimensional endothelial model and the MRI slice data, and the portion of the intersection curve of the MRI three-dimensional endothelial model and the MRI slice within the cuboid is the slice line segment.

[0015] Furthermore, displaying a point to be marked at a middle position between the first slice line segment and the second slice line segment includes: displaying the point to be marked in a mapping system operation interface in a color different from that of the MRI three-dimensional endothelial model.

[0016] Furthermore, the correction of the MRI three-dimensional endocardial model based on the position data of the point to be marked and the first slicing line segment and the second slicing line segment includes: interpolating the data between the first slicing line segment and the second slicing line segment based on the position data of the point to be marked and the coordinate points of the first slicing line segment and the second slicing line segment.

[0017] In another embodiment, the present invention further provides a cardiac three-dimensional modeling system based on cardiac three-dimensional mapping, characterized in that the system includes the following modules: a modeling module, used to perform MRI modeling of the target heart to obtain an MRI three-dimensional endocardial model and corresponding MRI slice data; a mapping module, used to perform preliminary mapping of the target heart to obtain a local endocardial model; a matching module, used to translate, rotate and scale the MRI three-dimensional endocardial model based on the local endocardial model, so that the local endocardial model overlaps with the endocardium of the MRI three-dimensional endocardial model; a first calculation module, used to obtain a first slice line according to the MRI three-dimensional endocardial model, the MRI slice data and the first spatial window. a first slice line segment and a second slice line segment, wherein the slice line segment refers to the intersection line of the MRI slice and the MRI three-dimensional endocardial model, and the first slice line segment and the second slice line segment are two adjacent slice line segments; a second calculation module, used for calculating the similarity between the first slice line segment and the second slice line segment; when the similarity between the first slice line segment and the second slice line segment is less than a first threshold, a point to be marked is displayed at the middle position of the first slice line segment and the second slice line segment; the marking module is further used for marking the point to be marked by using a marking catheter to obtain the position data of the point to be marked; and a correction module, used for correcting the MRI three-dimensional endocardial model according to the position data of the point to be marked and the first slice line segment and the second slice line segment.

[0018] Furthermore, the first spatial window is a cuboid in the local endothelial model coordinate system, and the cuboid moves in the MRI three-dimensional endothelial model coordinate system with a first step length.

[0019] Furthermore, acquiring the first slice line segment and the second slice line segment according to the MRI three-dimensional endothelial model, the MRI slice data and the first spatial window includes: obtaining an intersection curve of the MRI three-dimensional endothelial model and the MRI slice according to the MRI three-dimensional endothelial model and the MRI slice data, and the portion of the intersection curve of the MRI three-dimensional endothelial model and the MRI slice within the cuboid is the slice line segment.

[0020] Furthermore, displaying a point to be marked at a middle position between the first slice line segment and the second slice line segment includes: displaying the point to be marked in a mapping system operation interface in a color different from that of the MRI three-dimensional endothelial model.

[0021] Furthermore, the correction of the MRI three-dimensional endocardial model based on the position data of the point to be marked and the first slicing line segment and the second slicing line segment includes: interpolating the data between the first slicing line segment and the second slicing line segment based on the position data of the point to be marked and the coordinate points of the first slicing line segment and the second slicing line segment.

[0022] The present invention, through the above technical solution, after obtaining a part of the heart's endocardial model, superimposes the MRI three-dimensional model on the endocardial model, and determines the points that need further mapping by calculating the similarity between two slice segments in the MRI model, and corrects the MRI model according to the further mapping, thereby obtaining a more accurate three-dimensional model. In addition, since the three-dimensional model is mainly based on the MRI model, the present invention only needs to map the points prompted by the system, so when performing three-dimensional modeling, it is faster than the ordinary mapping method.

[0023] The present invention segments the MRI image through the image segmentation function, so that the segmented image is easier to process subsequently. The establishment of the function involves image pixels, image noise, MRI slice number, image grayscale value, etc. By fusing these variables, the segmented image is more convenient to process. The function is based on existing theories, is simple and easy to understand, and can effectively improve the accuracy of three-dimensional coordinate modeling of the heart. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 Schematic diagram of the method of the present invention. Implementation

[0026] Below, the invention is preferably described in conjunction with the accompanying drawings and specific implementation methods.

[0027] This embodiment solves the above problem through the following steps:

[0028] In one embodiment, reference Figure 1 The present invention provides a three-dimensional cardiac modeling method based on three-dimensional cardiac mapping.

[0029] The method of this embodiment is a further improvement on the existing mapping system. It can be implemented by modifying the source code of the existing mapping system, or by an interface or plug-in program provided by the system. The mapping system described in this embodiment refers to the improved mapping system according to the method of this embodiment.

[0030] Perform MRI modeling on the target heart to obtain an MRI three-dimensional endocardial model and corresponding MRI slice data.

[0031] The target heart refers to the heart to be three-dimensionally modeled. MRI modeling of the target heart first requires RMI scanning. The scanned structure is usually a plurality of RMI slice image data. And the scanned results are preprocessed, such as removing artifacts, image smoothing, grayscale standardization, etc. These steps can be completed by image processing software. However, the heart is segmented, and the heart is separated from the MRI image using a segmentation algorithm. Traditional threshold segmentation, edge detection, region growth, horizontal line segmentation and other algorithms can be used, or deep learning methods such as U-Net can be used. After that, the segmented heart data is three-dimensionally reconstructed, and common three-dimensional visualization software such as Amira, Mimics, 3D Slicer, etc. can be used. During the reconstruction process, the slice data needs to be interpolated. It should be noted that the steps and techniques listed in the above MRI modeling are all conventional means in the prior art. As long as cardiac MRI modeling can be achieved, this embodiment does not make too many restrictions.

[0032] Image segmentation function, the expression is:

[0033]

[0034]

[0035]

[0036] in, represents the positioning function, Represents the horizontal coordinate of the image pixel. Indicates the direction of the horizontal coordinate of the image pixel point, Represents the vertical coordinate of the image pixel. represents the image noise coefficient, represents the Gaussian white noise of the image, Indicates the size of the MRI three-dimensional endothelium, m represents the number of MRI slices, Indicates the size of the image after segmentation is completed. Represents the number of image segmentation targets, Represents the grayscale value of the image, represents the image segmentation speed, represents the tube side of the three-dimensional image, j Represents a constant, which is related to the image clarity. Represents the intimal overlap rate of the MRI three-dimensional intimal model.

[0037] The present invention segments the MRI image through the image segmentation function, so that the segmented image is easier to process subsequently. The establishment of the function involves image pixels, image noise, MRI slice number, image grayscale value, etc. By fusing these variables, the segmented image is more convenient to process. The function is based on existing theories, is simple and easy to understand, and can effectively improve the accuracy of three-dimensional coordinate modeling of the heart.

[0038] This embodiment mainly models the endocardium of the heart, so the MRI modeling of this embodiment must include the endocardium model of the heart. In addition, the MRI slice data is the data used in modeling, which is needed in the following steps, and the MRI slice data corresponding to the establishment of the MRI three-dimensional endocardium model must be retained.

[0039] Perform preliminary mapping of the target heart and obtain a local endocardial model.

[0040] When mapping the patient's heart, the catheter is sent into the heart through the vein. When the catheter head contacts the heart's endothelium, the absolute coordinates of the catheter head relative to each electrode can be obtained based on the change in potential, thereby establishing a three-dimensional model of the contact part of the catheter head.

[0041] For example, taking Carto3 as an example, the catheter usually enters the lower cavity first. By bending and rotating the catheter, a three-dimensional model of the lower cavity can be established. The first model of the lower cavity is the local endothelial model. A three-dimensional image of the lower cavity curved surface can be seen from the interface of the Carto3 system. The three-dimensional model of the lower cavity curved surface is the local endothelial model.

[0042] The size of the local endothelial model can be freely determined by the operating physician. It is known that the larger the local endothelial model is (the larger the curved surface is), the more accurate the matching result will be when the local endothelial model is matched with a three-dimensional model.

[0043] The local endothelial model is a model established in real time by the mapping system, and its coordinate system is determined according to the position of each electrode. Therefore, the coordinates of the local endothelial model are relative to the position of each electrode.

[0044] The local endocardial model can be acquired in real time. After each change of the endocardial model, the previously acquired endocardial model can be regarded as the local endocardial model, and the subsequent steps are executed after each change of the endocardial model. The local endocardial model can also be determined actively by the user. For example, when the doctor obtains a preliminary endocardial model and determines that the endocardial model can match the standard heart model, the doctor confirms on the operation interface that the acquired endocardial model is the local endocardial model.

[0045] The local endocardial model is used as a reference to translate, rotate and scale the MRI three-dimensional endocardial model so that the local endocardial model overlaps with the endocardium of the MRI three-dimensional endocardial model.

[0046] The local endocardial model is a real-time model displayed on the mapping system, which is a true reflection of the real heart. Therefore, the local endocardial model needs to be used as a reference, and the standard heart 3D model needs to be loaded into the same coordinate system as the local endocardial model, and have the same rotation and scaling level as the local endocardial model. For example, when the model of the upper chamber of the heart is determined using the mapping system, the upper chamber of the heart is displayed on the operation interface, and the standard heart 3D model is rotated, scaled, and translated so that the upper chamber of the standard heart 3D model coincides with the upper chamber of the local endocardial model.

[0047] Exemplarily, automatically rotating and scaling the inner model of the standard three-dimensional heart model so that the local endocardial model overlaps with the inner model of the standard three-dimensional heart model can be achieved by using the following method:

[0048] Since the heart structure is complex and the endocardial curvature varies greatly, the curvature can be used as a feature. First, the feature points of the local endocardial model and the standard heart 3D model are extracted using the Harris Corner Detection algorithm. The similarity of the feature points of the local endocardial model and the standard heart 3D model is calculated, and the feature point pairs with a similarity greater than a certain threshold are determined as corresponding point pairs.

[0049] After obtaining the feature point pairs of the two models, the feature point matching algorithm can be used to calculate the transformation matrix; any matching algorithm in the prior art can be used to determine the transformation matrix, such as the RANSAC (RANdom SAmpleConsensus) algorithm, the Iterative Closest Point (ICP) algorithm, the Least Squares algorithm, etc. The specific algorithm is not specifically limited in this embodiment, and any other algorithm other than the above examples can also be used as long as the transformation matrix can be calculated. Based on the transformation matrix, the scaling, translation, and rotation parameters of the standard heart three-dimensional model relative to the local endothelial model can be determined; the standard heart three-dimensional model can be superimposed on the local endothelial model by scaling, translating, and rotating the standard heart three-dimensional model accordingly.

[0050] It should be noted that the above operations are all completed by program automation based on the mapping system, and can be achieved by modifying the source code of the mapping system, calling the API of the mapping system, or using plug-in programs.

[0051] Acquire a first slice line segment and a second slice line segment according to the MRI three-dimensional endocardial model, the MRI slice data, and the first spatial window, wherein the slice line segment refers to a portion of an intersection line between the MRI slice and the MRI three-dimensional endocardial model within the first spatial window, and the first slice line segment and the second slice line segment are two adjacent slice line segments;

[0052] After aligning the MRI three-dimensional endothelial model with the local endothelial model, the MRI three-dimensional endothelial model is mapped to the coordinate system of the local endothelial model (that is, the coordinate system composed of several pairs of different adhesive electrodes mentioned in the background technology). The MRI three-dimensional endothelial model is saved in the coordinate system in the form of a surface, and the corresponding MRI slice data is scaled and rotated at the same scale. The MRI slices are represented as plane data in the three-dimensional coordinate system. According to the knowledge of spatial geometry, the intersection of the MRI three-dimensional endothelial model and the MRI slice data is a curve. Since MRI slices usually divide organs into equal intervals, the intersection of the MRI three-dimensional endothelial model and the MRI slice data is similar to the contour lines on a mountain.

[0053] Similar to the sliding window in image processing, this embodiment uses a spatial window to intercept the lines to be processed. The spatial window refers to an area in space, such as a sphere, a cuboid, etc. in space. The data falling within the spatial range is regarded as the data in the first spatial window. When the curve where the MRI three-dimensional endocardial model intersects with the MRI slice data intersects with the spatial window, there is a line segment surrounded by the spatial window, and this line segment is the slice line segment.

[0054] Further, for the convenience of calculation, the first spatial window is a cuboid (including a special cuboid such as a cube). The size of the cuboid can be selected according to the data scale of the heart model, and this embodiment does not specify an absolute value. The cuboid moves in the MRI three-dimensional endothelial model coordinate system with the first step length. For example, the cuboid starts from the origin, first keeps the y-axis and z-axis stationary, and moves one unit along the x-axis each time. When the x-axis moves to the maximum position (the maximum x of the MRI three-dimensional endothelial model), it moves one unit on the y-axis, the z-axis does not move, and x moves from the initial to the maximum again, and so on, until the entire space is traversed. It can be predicted by those skilled in the art that such iterative movement of the window in space will have a high probability of encountering a time when there is no intersection with the MRI three-dimensional endothelial model. Those skilled in the art can further optimize the algorithm to skip such cases to achieve a faster traversal speed.

[0055] The intersection curve of the MRI 3D endothelial model and the MRI slice is obtained according to the MRI 3D endothelial model and the MRI slice data, and the portion of the intersection curve of the MRI 3D endothelial model and the MRI slice within the cuboid is the slice line segment. For subsequent steps, when obtaining the slice line segment, two adjacent first slice line segments and second slice line segments need to be obtained.

[0056] Calculating the similarity between the first slicing line segment and the second slicing line segment; when the similarity between the first slicing line segment and the second slicing line segment is less than a first threshold, displaying a point to be marked at a middle position between the first slicing line segment and the second slicing line segment;

[0057] When the similarity between two slice segments is large, it means that the surface between the two slices is flat and the changes are small, such as two slice segments on a smooth surface, the overall trend is similar; the interpolation surface obtained by conventional interpolation can better simulate the real inner membrane. However, when the similarity between two slice segments is small, it means that the part between the two slices is severely distorted, such as a pothole appears on a smooth slope, one slice segment is outside the pothole, and another slice segment is inside the pothole; the rough surface is usually caused by lesions. If the conventional interpolation method is still used at this time, a large error may occur, leading to misdiagnosis. The calculation of similarity can adopt any method in the prior art, such as Euclidean distance, Pearson correlation coefficient, cosine similarity, etc.

[0058] In order to reduce the error of the three-dimensional model, in the case of a large change between two slices, the user is prompted to map the area once, and a point to be mapped is displayed at the middle position of the first slice line segment and the second slice line segment to obtain more accurate surface data between the two slices. Specifically, the point to be mapped can be displayed in a color different from the MRI three-dimensional endocardial model in the mapping system operation interface to facilitate the operator to use the catheter head to map the corresponding position.

[0059] It should be noted that the aforementioned middle position is not the exact middle in mathematical terms, but a position roughly in the middle. For example, the middle position can be regarded as within 10% to the left or right of the center line.

[0060] The mapping catheter is used to map the point to be mapped to obtain position data of the point to be mapped.

[0061] After the point to be measured is determined, the doctor operating the catheter can send the catheter head to the point to be measured, thereby obtaining the precise position of the point to be measured and determining the specific coordinates of the rough position on the intima.

[0062] The MRI three-dimensional endocardial model is corrected according to the position data of the to-be-marked point and the first slice line segment and the second slice line segment.

[0063] In the above steps, it is determined that there is a large change between the first slice line segment and the second slice line segment, and the position data of the point to be marked between the two segments is obtained, then a new precise point is added between the two segments, and these data can be used to re-interpolate, and the rough points on the endothelium and their coordinates can be found to achieve the purpose of improving the MRI three-dimensional endothelium model. At the same time, since the overall model uses the MRI model, the mapping only needs to map the prompted points to be marked, which greatly reduces the number of mapping times, facilitates the doctor's operation, and reduces the mapping time.

[0064] It can be predicted that the aforementioned steps are only a method for updating one model point, and in the entire mapping process, the aforementioned steps can be repeated for any number of points that need to be corrected.

[0065] In another embodiment, the present invention further provides a three-dimensional cardiac modeling system based on three-dimensional cardiac mapping, characterized in that the system comprises the following modules:

[0066] A modeling module, used to perform MRI modeling of the target heart to obtain an MRI three-dimensional endocardial model and corresponding MRI slice data;

[0067] A mapping module is used to perform preliminary mapping of the target heart and obtain a local endocardial model;

[0068] A matching module, used to translate, rotate and scale the MRI three-dimensional endothelial model based on the local endothelial model, so that the local endothelial model overlaps with the endothelial of the MRI three-dimensional endothelial model;

[0069] a first calculation module, configured to obtain a first slice line segment and a second slice line segment according to the MRI three-dimensional endocardial model, the MRI slice data, and a first spatial window, wherein the slice line segment refers to an intersection line between the MRI slice and the MRI three-dimensional endocardial model, and the first slice line segment and the second slice line segment are two adjacent slice line segments;

[0070] A second calculation module is used to calculate the similarity between the first slicing line segment and the second slicing line segment; when the similarity between the first slicing line segment and the second slicing line segment is less than a first threshold, a point to be marked is displayed at a middle position between the first slicing line segment and the second slicing line segment;

[0071] The mapping module is further used to map the to-be-mapped point using a mapping catheter to obtain position data of the to-be-mapped point;

[0072] A correction module is used to correct the MRI three-dimensional endocardial model according to the position data of the point to be marked and the first slice line segment and the second slice line segment.

[0073] It should be noted that the detailed implementation principle and further improvement measures for the above-mentioned cardiac three-dimensional modeling system based on cardiac three-dimensional mapping are the same as the aforementioned cardiac three-dimensional modeling method based on cardiac three-dimensional mapping, and will not be described in detail in this embodiment. Those skilled in the art can implement the cardiac three-dimensional modeling method based on cardiac three-dimensional mapping in the cardiac three-dimensional modeling system based on cardiac three-dimensional mapping according to the prior art.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

[0075] The present invention does not particularly specify the structure of some modules, which shall be subject to the contents recorded in the prior art. The prior art mentioned in the above background technology section and the specific embodiment section of the present invention can be used as part of the present invention to understand the meaning of some technical features or parameters. The scope of protection of the present invention shall be subject to the contents actually recorded in the claims.

Claims

1. A method for three-dimensional cardiac modeling based on three-dimensional cardiac mapping, characterized in that The method comprises the following steps: Acquire an MRI three-dimensional endocardial model and corresponding MRI slice data obtained after MRI modeling of the target heart; Acquire a local endocardial model obtained after preliminary mapping of the target heart; Taking the local endothelial model as a reference, translating, rotating and scaling the MRI three-dimensional endothelial model so that the local endothelial model overlaps with the endothelial of the MRI three-dimensional endothelial model; Acquire a first slice line segment and a second slice line segment according to the MRI three-dimensional endocardial model, the MRI slice data, and the first spatial window, wherein the slice line segment refers to a portion of an intersection line between the MRI slice and the MRI three-dimensional endocardial model within the first spatial window, and the first slice line segment and the second slice line segment are two adjacent slice line segments; Calculating the similarity between the first slice line segment and the second slice line segment; When the similarity between the first slicing line segment and the second slicing line segment is less than a first threshold, a point to be marked is displayed at a middle position between the first slicing line segment and the second slicing line segment; Using a mapping catheter to map the point to be mapped, and obtaining position data of the point to be mapped; The MRI three-dimensional endocardial model is corrected according to the position data of the to-be-marked point and the first slice line segment and the second slice line segment.

2. A method for three-dimensional cardiac modeling based on three-dimensional cardiac mapping according to claim 1, characterized in that: The first spatial window is a cuboid in the local endothelial model coordinate system, and the cuboid moves in the MRI three-dimensional endothelial model coordinate system with a first step length.

3. A method for three-dimensional cardiac modeling based on three-dimensional cardiac mapping according to claim 2, characterized in that The method of acquiring the first slice line segment and the second slice line segment according to the MRI three-dimensional endothelial model, the MRI slice data and the first spatial window includes: obtaining an intersection curve between the MRI three-dimensional endothelial model and the MRI slice according to the MRI three-dimensional endothelial model and the MRI slice data, wherein the portion of the intersection curve between the MRI three-dimensional endothelial model and the MRI slice within the cuboid is a slice line segment.

4. A method for three-dimensional cardiac modeling based on three-dimensional cardiac mapping according to claim 1, characterized in that Displaying a point to be marked at a middle position between the first slice line segment and the second slice line segment includes: displaying the point to be marked in a mapping system operation interface in a color different from the MRI three-dimensional endocardial model.

5. A method for three-dimensional cardiac modeling based on three-dimensional cardiac mapping according to claim 1, characterized in that The correction of the MRI three-dimensional endocardial model based on the position data of the point to be marked and the first slicing line segment and the second slicing line segment includes: interpolating the data between the first slicing line segment and the second slicing line segment based on the position data of the point to be marked and the coordinate points of the first slicing line segment and the second slicing line segment.

6. A cardiac three-dimensional modeling system based on cardiac three-dimensional mapping, characterized in that The system includes the following modules: The first acquisition module is used to acquire the MRI three-dimensional endocardial model and the corresponding MRI slice data obtained after MRI modeling of the target heart; the second acquisition module is used to acquire the local endocardial model obtained after preliminary mapping of the target heart; A matching module, used to translate, rotate and scale the MRI three-dimensional endothelial model based on the local endothelial model, so that the local endothelial model overlaps with the endothelial of the MRI three-dimensional endothelial model; a first calculation module, configured to obtain a first slice line segment and a second slice line segment according to the MRI three-dimensional endocardial model, the MRI slice data, and a first spatial window, wherein the slice line segment refers to a portion of an intersection line between the MRI slice and the MRI three-dimensional endocardial model within the first spatial window, and the first slice line segment and the second slice line segment are two adjacent slice line segments; A second calculation module, configured to calculate the similarity between the first slicing line segment and the second slicing line segment; When the similarity between the first slicing line segment and the second slicing line segment is less than a first threshold, a point to be marked is displayed at a middle position between the first slicing line segment and the second slicing line segment; A mapping module, used for mapping the points to be mapped using a mapping catheter to obtain position data of the points to be mapped; A correction module is used to correct the MRI three-dimensional endocardial model according to the position data of the point to be marked and the first slice line segment and the second slice line segment.

7. A cardiac three-dimensional modeling system based on cardiac three-dimensional mapping according to claim 6, characterized in that: The first spatial window is a cuboid in the local endothelial model coordinate system, and the cuboid moves in the MRI three-dimensional endothelial model coordinate system with a first step length.

8. A cardiac three-dimensional modeling system based on cardiac three-dimensional mapping according to claim 7, characterized in that The method of acquiring the first slice line segment and the second slice line segment according to the MRI three-dimensional endothelial model, the MRI slice data and the first spatial window includes: obtaining an intersection curve between the MRI three-dimensional endothelial model and the MRI slice according to the MRI three-dimensional endothelial model and the MRI slice data, wherein the portion of the intersection curve between the MRI three-dimensional endothelial model and the MRI slice within the cuboid is a slice line segment.

9. A cardiac three-dimensional modeling system based on cardiac three-dimensional mapping according to claim 6, characterized in that Displaying a point to be marked at a middle position between the first slice line segment and the second slice line segment includes: displaying the point to be marked in a mapping system operation interface in a color different from the MRI three-dimensional endocardial model.

10. A cardiac three-dimensional modeling system based on cardiac three-dimensional mapping according to claim 6, characterized in that The correction of the MRI three-dimensional endocardial model based on the position data of the point to be marked and the first slicing line segment and the second slicing line segment includes: interpolating the data between the first slicing line segment and the second slicing line segment based on the position data of the point to be marked and the coordinate points of the first slicing line segment and the second slicing line segment.

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