Electrical field ablation region determination method and apparatus, computer device, and storage medium

Abstract

The application relates to an electric field ablation region determination method and device, computer equipment and a storage medium. The method comprises the following steps: establishing a first three-dimensional model of a lesion region; establishing a first local coordinate system of the lesion region according to the first three-dimensional model; acquiring each plane field strength contour line in a reference surface, and establishing a second local coordinate system of the reference surface; mapping each plane field strength contour line on the first three-dimensional model according to a first center coordinate point of the lesion region, a common second center coordinate point of each plane field strength contour line, the first local coordinate system and the second local coordinate system; acquiring a target plane field strength contour line, and a target space field strength closed body obtained by extending the target plane field strength contour line along a main coordinate axis direction of the first local coordinate system surrounds the first three-dimensional model; and a space electric field ablation region corresponding to the target plane field strength contour line is a target electric field ablation region. The method can save the time for calculating the field strength contour line.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to an electric field ablation region determination method and device, computer equipment and storage medium. BACKGROUND

[0002] When irreversible electroporation ablates a lesion, the range of electric field strength isoline needs to be known. In the traditional scheme, the space is usually divided into a finite number of cubes, and the electric potential at the intersection coordinates of the cubes is calculated by iterative calculation using the finite element method. Then the electric field strength isoline is extracted by taking the gradient of the electric potential, and then visualized. Finally, it is observed whether the field strength surrounds the lesion region in the space.

[0003] The way of calculating the electric potential of each cube in the space by iterative calculation using the finite element method until convergence, and then extracting the electric field strength isoline, is very time-consuming. SUMMARY

[0004] Therefore, it is necessary to provide an electric field ablation region determination method and device, computer equipment, storage medium and computer program product capable of quickly extracting the target electric field strength isoline in order to solve the above technical problems.

[0005] In a first aspect, the present application provides an electric field ablation region determination method, which comprises:

[0006] establishing a first three-dimensional model of a lesion region;

[0007] establishing a first local coordinate system of the lesion region according to the first three-dimensional model;

[0008] obtaining each plane electric field strength isoline in a reference plane, and establishing a second local coordinate system of the reference plane, wherein the reference plane is an arbitrary plane;

[0009] mapping each plane electric field strength isoline on the first three-dimensional model according to the first center coordinate point of the lesion region, the common second center coordinate point of each plane electric field strength isoline, the first local coordinate system and the second local coordinate system;

[0010] obtaining a target plane electric field strength isoline, wherein a target space electric field strength closed body obtained by extending the target plane electric field strength isoline along the direction of the main coordinate axis of the first local coordinate system surrounds the first three-dimensional model, the direction of the main coordinate axis is parallel to the direction of needle insertion of the ablation needle, and the space electric field ablation region corresponding to the target plane electric field strength isoline is a target electric field ablation region.

[0011] In one of the embodiments, the obtaining of the target plane electric field strength isoline comprises:

[0012] obtaining each candidate plane field intensity contour, and a spatial field intensity closed body obtained by extending each candidate plane field intensity contour along a main axis direction of the first local coordinate system surrounds the first three-dimensional model;

[0013] determining a plane field intensity contour with the smallest enclosed area among each candidate plane field intensity contour as the target plane field intensity contour.

[0014] In one of the embodiments, before the target plane field intensity contour is obtained, the method further comprises:

[0015] obtaining a maximum projection value and a minimum projection value of each surface coordinate point of the first three-dimensional model on a main coordinate axis of the first local coordinate system;

[0016] constructing a spatial field intensity closed body corresponding to each plane field intensity contour according to the maximum projection value, the minimum projection value and each plane field intensity contour.

[0017] In one of the embodiments, before the target plane field intensity contour is obtained, the method further comprises:

[0018] if the number of intersection points of a ray along any direction of each surface coordinate point and the spatial field intensity closed body is an odd number, it is determined that the spatial field intensity closed body surrounds the first three-dimensional model.

[0019] In one of the embodiments, before the target plane field intensity contour surrounding the lesion area is obtained, the method further comprises:

[0020] obtaining a reference plane based on the surface coordinate point, and obtaining a cross section of the spatial field intensity closed body cut by the reference plane, wherein the surface coordinate point is located on the reference plane;

[0021] if the number of windings of the contour line of the cross section on the surface coordinate point is 1, it is determined that the surface coordinate point is inside the spatial field intensity closed body.

[0022] if it is determined that each surface coordinate point is inside the spatial field intensity closed body, the spatial field intensity closed body surrounds the first three-dimensional model.

[0023] In one of the embodiments, the method further comprises:

[0024] establishing a second three-dimensional model of important tissues located around the lesion area;

[0025] If each of the important tissues is not completely located outside the target spatial field strength enclosure according to the first three-dimensional model and the second three-dimensional model, adjusting a position and an ablation parameter of the target spatial field strength enclosure until each of the important tissues is completely located outside the target spatial field strength enclosure, wherein the ablation parameter comprises at least one of an electrode needle voltage, an ablation needle number, and an ablation needle spacing.

[0026] In one of the embodiments, the method further comprises:

[0027] If the target planar field strength contour does not exist, adjusting an ablation parameter to adjust a surrounding area of each planar field strength contour until the target planar field strength contour appears, wherein the ablation parameter comprises at least one of an electrode needle voltage, an ablation needle number, and an ablation needle spacing.

[0028] In one of the embodiments, the method further comprises:

[0029] Adjusting an ablation parameter to adjust a size of the target spatial field strength enclosure until a distance between the target spatial field strength enclosure and the closest surface coordinate point is within a preset range, wherein the ablation parameter comprises at least one of an electrode needle voltage, an ablation needle number, and an ablation needle spacing.

[0030] In one of the embodiments, the first local coordinate system of the lesion area is established according to the first three-dimensional model, comprising:

[0031] Obtaining a covariance matrix of the lesion area according to each surface coordinate point of the first three-dimensional model and the first center coordinate point;

[0032] Performing eigenvalue decomposition on the covariance matrix to obtain a maximum eigenvector and a second maximum eigenvector as a first coordinate axis and a second coordinate axis of the first local coordinate system, wherein the first coordinate axis is a principal coordinate axis of the first local coordinate system;

[0033] Performing a cross product on the maximum eigenvector and the second maximum eigenvector to obtain a third coordinate axis of the first local coordinate system.

[0034] In one of the embodiments, the second local coordinate system of the reference surface is established, comprising:

[0035] Establishing the second local coordinate system by taking a normal line of the reference surface as a first coordinate axis and taking a first vector and a second vector in the reference surface and perpendicular to each other as a second coordinate axis and a third coordinate axis respectively.

[0036] In one of the embodiments, the mapping of each planar field intensity contour onto the first three-dimensional model according to the first central coordinate point of the lesion region, the second central coordinate point common to each of the planar field intensity contours, the first local coordinate system and the second local coordinate system comprises:

[0037] acquiring a spatial conversion matrix corresponding to the second central coordinate point and the first central coordinate point and corresponding to each coordinate axis of the second local coordinate system and each coordinate axis of the first local coordinate system, wherein the first coordinate axis, the second coordinate axis and the third coordinate axis of the second local coordinate system correspond to the first coordinate axis, the second coordinate axis and the third coordinate axis of the first local coordinate system respectively;

[0038] mapping each planar field intensity contour onto the first three-dimensional model according to the spatial conversion matrix.

[0039] In a second aspect, the present application further provides an electric field ablation region determination device. The device comprises:

[0040] a first establishing module configured to establish a first three-dimensional model of a lesion region;

[0041] a second establishing module configured to establish a first local coordinate system of the lesion region according to the first three-dimensional model;

[0042] a third establishing module configured to acquire each planar field intensity contour in a reference plane and establish a second local coordinate system of the reference plane, wherein the reference plane is an arbitrary plane;

[0043] a mapping module configured to map each planar field intensity contour onto the first three-dimensional model according to the first central coordinate point of the lesion region, the second central coordinate point common to each of the planar field intensity contours, the first local coordinate system and the second local coordinate system;

[0044] a determination module configured to acquire a target planar field intensity contour, wherein a target spatial field intensity closed body obtained by extending the target planar field intensity contour along a main coordinate axis direction of the first local coordinate system encloses the first three-dimensional model, the main coordinate axis direction is parallel to an ablation needle insertion direction, and a spatial electric field ablation region corresponding to the target planar field intensity contour is a target electric field ablation region.

[0045] In a third aspect, the present application further provides a computer device. The computer device comprises a memory and a processor, the memory stores a computer program, and the processor realizes the following steps when executing the computer program:

[0046] establishing a first three-dimensional model of a lesion region;

[0047] establishing a first local coordinate system of the lesion area according to the first three-dimensional model;

[0048] obtaining each planar field strength contour in the reference plane, and establishing a second local coordinate system of the reference plane, wherein the reference plane is an arbitrary plane;

[0049] mapping each planar field strength contour to the first three-dimensional model according to the first center coordinate point of the lesion area, the common second center coordinate point of each planar field strength contour, the first local coordinate system, and the second local coordinate system;

[0050] obtaining a target planar field strength contour, the target planar field strength contour being enclosed by a target spatial field strength closed body extending along a main coordinate axis direction of the first local coordinate system, the main coordinate axis direction being parallel to the needle insertion direction of the ablation needle, and a spatial electric field ablation area corresponding to the target planar field strength contour being a target electric field ablation area.

[0051] In a fourth aspect, the present application further provides a computer readable storage medium. The computer readable storage medium has a computer program stored thereon, and the computer program is executed by a processor to implement the following steps:

[0052] establishing a first three-dimensional model of a lesion area;

[0053] establishing a first local coordinate system of the lesion area according to the first three-dimensional model;

[0054] obtaining each planar field strength contour in the reference plane, and establishing a second local coordinate system of the reference plane, wherein the reference plane is an arbitrary plane;

[0055] mapping each planar field strength contour to the first three-dimensional model according to the first center coordinate point of the lesion area, the common second center coordinate point of each planar field strength contour, the first local coordinate system, and the second local coordinate system;

[0056] obtaining a target planar field strength contour, the target planar field strength contour being enclosed by a target spatial field strength closed body extending along a main coordinate axis direction of the first local coordinate system, the main coordinate axis direction being parallel to the needle insertion direction of the ablation needle, and a spatial electric field ablation area corresponding to the target planar field strength contour being a target electric field ablation area.

[0057] In a fifth aspect, the present application further provides a computer program product. The computer program product comprises a computer program, and the computer program is executed by a processor to implement the following steps:

[0058] establishing a first three-dimensional model of a lesion area;

[0059] establishing a first local coordinate system of the lesion area according to the first three-dimensional model;

[0060] obtaining each plane field strength contour in the reference plane, and establishing a second local coordinate system of the reference plane, wherein the reference plane is an arbitrary plane;

[0061] mapping each plane field strength contour on the first three-dimensional model according to the first center coordinate point of the lesion area, the common second center coordinate point of each plane field strength contour, the first local coordinate system, and the second local coordinate system;

[0062] obtaining a target plane field strength contour, the target plane field strength contour being surrounded by a target space field strength closed body obtained by extending each plane field strength contour along a main coordinate axis direction of the first local coordinate system, the main coordinate axis direction being parallel to the needle insertion direction of the ablation needle, and the space electric field ablation area corresponding to the target plane field strength contour being a target electric field ablation area.

[0063] The electric field ablation area determination method, device, computer device, storage medium, and computer program product, by obtaining the plane field strength contour in the reference plane, only need to calculate the two-dimensional plane field strength contour, greatly saving the time for calculating the field strength contour. After establishing the first local coordinate system of the lesion area and the second local coordinate system of the reference plane, mapping each plane field strength contour on the first three-dimensional model according to the first center coordinate point of the lesion area, the common second center coordinate point of each plane field strength contour, the first local coordinate system, and the second local coordinate system, it can be accurately determined whether the space field strength closed body obtained by extending each plane field strength contour along the main coordinate axis direction of the first local coordinate system can surround the lesion area, and then the target space field strength closed body and the target plane field strength contour corresponding thereto are determined. Since the space electric field ablation area corresponding to the target plane field strength contour is the target electric field ablation area, the finally determined target electric field ablation area can completely ablate the lesion area. BRIEF DESCRIPTION OF DRAWINGS

[0064] Figure 1 It is a flowchart of the electric field ablation area determination method in one embodiment;

[0065] Figure 2 It is a schematic diagram of the first three-dimensional model in one embodiment;

[0066] Figure 3 It is a schematic diagram of establishing the first local coordinate system in one embodiment;

[0067] Figure 4 It is a schematic diagram of each plane field strength contour on the reference plane in one embodiment;

[0068] Figure 5 A schematic diagram of establishing a second local coordinate system in an embodiment;

[0069] Figure 6 A schematic diagram of mapping the plane field strength contour to the first three-dimensional model in an embodiment;

[0070] Figure 7 A schematic diagram of forming a spatial field strength closed body in an embodiment;

[0071] Figure 8 A schematic diagram of a spatial field strength closed body in an embodiment;

[0072] Figure 9 A schematic diagram of a flowchart of obtaining the target plane field strength contour in an embodiment;

[0073] Figure 10 A schematic diagram of obtaining the maximum projection value and the minimum projection value in an embodiment;

[0074] Figure 11 A schematic diagram of determining whether the surface coordinate point is located in the spatial field strength closed body by using the ray in an embodiment;

[0075] Figure 12 A schematic diagram of determining whether the surface coordinate point is located in the spatial field strength closed body by using the winding number in an embodiment;

[0076] Figure 13 A schematic diagram of adjusting the orientation of the spatial field strength closed body in an embodiment;

[0077] Figure 14 A schematic diagram of adjusting the orientation and the surrounding range of the spatial field strength closed body in an embodiment;

[0078] Figure 15 A schematic diagram of adjusting the surrounding range of the spatial field strength closed body in an embodiment;

[0079] Figure 16 A schematic diagram of a flowchart of the method for determining the electric field ablation region in another embodiment;

[0080] Figure 17 A schematic diagram of the structure of the device for determining the electric field ablation region in an embodiment;

[0081] Figure 18 An internal structure diagram of a computer device in an embodiment. DETAILED DESCRIPTION

[0082] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not intended to limit the present application.

[0083] In one embodiment, as shown in Figure 1 The present application provides an electric field ablation region determination method, which comprises:

[0084] S101: Establishing a first three-dimensional model of a lesion region.

[0085] In the application, as shown in Figure 2 The three-dimensional model can be obtained by three-dimensional reconstruction according to magnetic resonance imaging (MRI) data and / or ultrasound data of the lesion region. Exemplarily, the three-dimensional modeling process comprises: obtaining the vertex coordinates and the matrix of the topological relationship of the lesion region by segmenting and reconstructing the ultrasound or nuclear magnetic data, and then obtaining the data of the slice layer of the lesion and reconstructing.

[0086] S102: Establishing a first local coordinate system of the lesion region according to the first three-dimensional model.

[0087] Exemplarily, as shown in Figure 3 After the lesion region 32 is determined in the preoperative organization 31, the first local coordinate system of the lesion region 32 can be established by principal component analysis to improve the processing speed. Specifically, the coordinate mean of each surface coordinate point of the first three-dimensional model can be obtained to obtain the coordinate of the first center coordinate point 321; the covariance matrix of the lesion region 32 can be obtained according to each surface coordinate point of the first three-dimensional model and the first center coordinate point 321; the maximum eigenvalue and the second maximum eigenvalue are obtained by eigenvalue decomposition of the covariance matrix as the first coordinate axis and the second coordinate axis of the first local coordinate system, wherein the first coordinate axis is the principal coordinate axis of the first local coordinate system; the cross product of the maximum eigenvalue and the second maximum eigenvalue is obtained to obtain the third coordinate axis of the first local coordinate system. Wherein the first coordinate axis can be the Z axis, which is also the principal coordinate axis, and the second coordinate axis and the third coordinate axis can be the X axis and the Y axis respectively. Each surface coordinate point of the first three-dimensional model is a uniformly selected surface point of the first three-dimensional model containing coordinate information.

[0088] S103: Obtaining each plane field strength contour in the reference surface to establish a second local coordinate system of the reference surface, wherein the reference surface is an arbitrary plane.

[0089] Wherein, the plane field strength contour is the two-dimensional plane shape of the corresponding space field strength contour on the reference surface. For example,Figure 4 As shown, the planar field strength contour line 42 is formed on the reference plane 43 around the needle entry point 41.

[0090] Specifically, the process of calculating the planar field strength contour line 42 is as follows:

[0091] Figure 4 The potentials of the two needle entry points 41 are input potentials V1 and V2.

[0092] According to the Laplace equation

[0093]

[0094] where, is the divergence, and σ is the conductivity, is the gradient, is the potential. Assuming that the conductivity of the tissue is isotropic, in formula (1), its divergence is 0.

[0095] According to the input potentials V1 and V2, formula (1), and the first type of boundary condition or the second type of boundary condition, the potential of each grid point of the reference plane 43 (the reference plane 43 is pre-formed with a grid) can be solved by using the finite element method, and the planar field strength contour line 42 can be extracted by taking the derivative of the potential.

[0096] Alternatively, as shown in Figure 4 and Figure 5 , the normal of the reference plane 43 can be taken as the first coordinate axis, and the first vector and the second vector in the reference plane 43 that are perpendicular to each other can be taken as the second coordinate axis and the third coordinate axis respectively to establish a second local coordinate system of the reference plane 43. For example, the normal of the reference plane 43 is taken as the Z axis, and the first vector and the second vector are taken as the X axis and the Y axis respectively to construct the second local coordinate system.

[0097] S104: mapping each planar field strength contour line to the first three-dimensional model according to the first center coordinate point of the lesion area, the common second center coordinate point of each planar field strength contour line, the first local coordinate system, and the second local coordinate system.

[0098] wherein the first center coordinate point is the geometric center point of the lesion area containing coordinate information, and similarly, the second center coordinate point is the common geometric center point of each planar field strength contour line containing coordinate information.

[0099] In application, as shown in Figure 6As shown, by corresponding the coordinate axes of the first local coordinate system and the second local coordinate system, and by corresponding the first center coordinate point 321 and the second center coordinate point 44, the second local coordinate system can be transferred to the first three-dimensional model as a whole, and then it can be determined whether the plane field strength contour lines 42 in the second local coordinate system enclose the first three-dimensional model (i.e., the lesion region 32) in the same coordinate system, thereby ensuring the accuracy of the determination result.

[0100] S105: obtaining a target plane field strength contour line, the target plane field strength contour line being capable of enclosing the first three-dimensional model along a main coordinate axis direction of the first local coordinate system, the main coordinate axis direction being parallel to the needle insertion direction, and a spatial electric field ablation region corresponding to the target plane field strength contour line being a target electric field ablation region.

[0101] As shown in the application, Figure 7 and Figure 8 As shown, the needle insertion is parallel, that is, the axis directions of the needle insertion are parallel to each other. Since the needle insertion direction is also parallel to the main coordinate axis, the plane field strength contour lines 42 can be extended upward and downward along the main coordinate axis to construct the spatial field strength closed body 81. The extension length of each plane field strength contour line 42 in the main coordinate axis direction of the first local coordinate system is greater than the projection length of the first three-dimensional model (lesion region) in the main coordinate axis direction, so that the spatial field strength closed body corresponding to each plane field strength contour line can enclose the lesion region in the main coordinate axis direction. Specifically, whether the spatial field strength closed body 81 encloses the first three-dimensional model can be determined by determining whether each surface coordinate point 71 of the first three-dimensional model is within the spatial field strength closed body 81.

[0102] The above-mentioned electric field ablation region determination method can greatly save the time for calculating the field strength contour line by obtaining the plane field strength contour line in the reference plane, and by mapping each plane field strength contour line on the first three-dimensional model according to the first center coordinate point of the lesion region, the common second center coordinate point of each plane field strength contour line, the first local coordinate system, and the second local coordinate system, it can be accurately determined whether the spatial field strength closed body obtained by extending each plane field strength contour line in the main coordinate axis direction of the first local coordinate system can enclose the lesion region, and then the target spatial field strength closed body and the target plane field strength contour line corresponding thereto can be determined. Since the spatial electric field ablation region corresponding to the target plane field strength contour line is the target electric field ablation region, the finally determined target electric field ablation region can completely ablate the lesion region.

[0103] In one embodiment, as shown in Figure 9 the method for obtaining the target plane field strength contour line comprises:

[0104] S901: Obtain each candidate plane field strength contour, and a spatial field strength closed body corresponding to each candidate plane field strength contour is capable of enclosing the first three-dimensional model.

[0105] It can be understood that there can be multiple plane field strength contours corresponding to the spatial field strength closed body capable of enclosing the first three-dimensional model (i.e., the lesion region). Therefore, in order to determine the final target plane field strength contour, the plane field strength contour corresponding to the spatial field strength closed body capable of enclosing the lesion region is determined as the candidate plane field strength contour, and the target plane field strength contour is further selected from each candidate plane field strength contour.

[0106] S902: Determine the plane field strength contour with the smallest enclosed area among each candidate plane field strength contour as the target plane field strength contour.

[0107] It can be understood that the plane field strength contour with the smallest enclosed area among each candidate plane field strength contour is determined as the target plane field strength contour, the spatial electric field ablation region corresponding to the target plane field strength contour is the target electric field ablation region, so that the target electric field ablation region is capable of enclosing the lesion region and the ablation range is the smallest, which is beneficial to reduce the ablation area of the benign tissue.

[0108] In one embodiment, before the target plane field strength contour is obtained, the method for determining the electric field ablation region further comprises: obtaining the maximum projection value and the minimum projection value of each surface coordinate point of the first three-dimensional model on the main coordinate axis of the first local coordinate system; and constructing the spatial field strength closed body corresponding to each plane field strength contour according to the maximum projection value, the minimum projection value, and each plane field strength contour.

[0109] As shown in Figure 10 , the coordinate of the projection point of each surface coordinate point on the main coordinate axis is the projection value, each surface coordinate point has a corresponding projection value, and the maximum projection value and the minimum projection value are the coordinate boundaries of the lesion region on the first coordinate axis of the first local coordinate system. As shown in Figure 7 and 8 , the plane field strength contour is extended upwards and downwards along the main axis of the lesion; the extended plane field strength is enclosed to exceed the maximum projection value and the minimum projection value of the lesion region on the main coordinate axis, and they exceed the maximum projection value and the minimum projection value by a very small value, and the top and bottom field strength contours are connected to form a spatial field strength closed body, so that the spatial field strength closed body corresponding to each plane field strength contour is capable of enclosing the lesion region in the direction of the main coordinate axis.

[0110] In one embodiment, before the step of obtaining the target planar field strength contour surrounding the lesion region, the method further comprises: if the number of intersection points of the ray along any direction of each surface coordinate point with the spatial field strength closed body is odd, then determining that the spatial field strength closed body surrounds the first three-dimensional model.

[0111] It can be understood that, as shown in FIG. 7, when the surface coordinate point 71 is inside the spatial field strength closed body 81, a ray is emitted from the surface coordinate point 71 along any direction in space, and the ray only intersects the boundary of the spatial field strength closed body 81 once, that is, the number of intersection points of the surface coordinate point 71 with the spatial field strength closed body 81 is odd. When the surface coordinate point 71 is outside the spatial field strength closed body 81, the ray only intersects the boundary of the spatial field strength closed body 81 twice, that is, the number of intersection points of the surface coordinate point 71 with the spatial field strength closed body 81 is even. Figure 11

[0112] In one embodiment, before the step of obtaining the target planar field strength contour surrounding the lesion region, the method further comprises: obtaining a reference plane based on the surface coordinate points, and obtaining a cross section of the spatial field strength closed body intercepted by the reference plane, wherein the surface coordinate points are located on the reference plane; if the number of windings of the contour line of the cross section with respect to the surface coordinate point is 1, then determining that the surface coordinate point is inside the spatial field strength closed body; and if it is determined that each surface coordinate point is inside the spatial field strength closed body, then the step of determining that the spatial field strength closed body surrounds the first three-dimensional model.

[0113] In one embodiment, the reference plane is any plane containing the surface coordinate points, and each surface coordinate point has a corresponding reference plane.

[0114] It can be understood that, as shown in FIG. 7, when the surface coordinate point 71 is inside the spatial field strength closed body 81, a ray is emitted from the surface coordinate point 71 along any direction in space, and the ray only intersects the boundary of the spatial field strength closed body 81 once, that is, the number of intersection points of the surface coordinate point 71 with the spatial field strength closed body 81 is odd. When the surface coordinate point 71 is outside the spatial field strength closed body 81, the ray only intersects the boundary of the spatial field strength closed body 81 twice, that is, the number of intersection points of the surface coordinate point 71 with the spatial field strength closed body 81 is even. Figure 12 Figure 12 As shown in FIG. 12, after obtaining the cross section of the spatial field strength closed body 81 intercepted by the reference plane 121, we can imagine that the contour line 122 of the cross section is the motion trajectory of an object, the motion direction is counterclockwise, and the number of windings of the curve is the total number of times the object passes through the origin counterclockwise. When the surface coordinate point 71 is inside the cross section, the contour line 122 of the cross section passes through the surface coordinate point 71 once counterclockwise, and the number of windings of the contour line 122 of the cross section with respect to the surface coordinate point 71 is 1 (as shown in FIG. 7A and FIG. 7B). When the surface coordinate point 71 is outside the cross section, the contour line 122 of the cross section does not pass through the surface coordinate point 71, and the number of windings of the cross section with respect to the surface coordinate point 71 is 0 (as shown in FIG. 7C and FIG. 7D). Figure 12 ​​C) in FIG. 6. Therefore, by judging the winding number of the profile line 122 of the cross section with respect to the surface coordinate point 71, it can be determined whether the surface coordinate point 71 is located in the cross section, i.e., in the spatial field strength closed body 81. By judging whether each surface coordinate point 71 is located in the spatial field strength closed body 81, it can be understood that each surface coordinate point 71 is located in the spatial field strength closed body 81, and thus the spatial field strength closed body 81 encloses the first three-dimensional model. Further, it can be determined that the planar field strength contour corresponding to the spatial field strength closed body 81 is the candidate planar field strength contour.

[0115] In one embodiment, the electric field ablation region determination method further comprises: establishing a second three-dimensional model of important tissues located around the lesion region; and adjusting the position and ablation parameters of the target spatial field strength closed body until the important tissues are completely located outside the target spatial field strength closed body, in the case that each important tissue is not completely located outside the target spatial field strength closed body according to the first three-dimensional model and the second three-dimensional model, wherein the ablation parameters include at least one of the electrode needle voltage, the number of ablation needles, and the ablation needle spacing.

[0116] In one embodiment, the electric field ablation region determination method further comprises: establishing a second three-dimensional model of important tissues located around the lesion region; and adjusting the position and ablation parameters of the target spatial field strength closed body until the important tissues are completely located outside the target spatial field strength closed body, in the case that each important tissue is not completely located outside the target spatial field strength closed body according to the first three-dimensional model and the second three-dimensional model, wherein the ablation parameters include at least one of the electrode needle voltage, the number of ablation needles, and the ablation needle spacing.

[0117] Specifically, first, the image sequence of the important tissues around the lesion region is segmented; and a second three-dimensional model is established based on the segmented image data of the important tissues. After the second three-dimensional model is established, the positional relationship between the lesion region and the important tissue region can be determined by comprehensively considering the first three-dimensional model and the second three-dimensional model, and then a three-dimensional model including the lesion region and the important tissue region can be formed. After the target planar field strength contour is determined, it can be judged whether each surface coordinate point of the important tissue region is located in the target spatial field strength closed body, and the judgment manner can be the same as that for judging whether the surface coordinate point of the lesion region is located in the target spatial field strength closed body.

[0118] Illustratively, a ray is emitted in an arbitrary direction of space with the surface coordinate point of the important tissue region as the starting point. If the number of intersection points of the surface coordinate point with the spatial field strength closed body is odd, it is determined that the spatial field strength closed body encloses the surface coordinate point.

[0119] Illustratively, a reference plane is obtained based on the surface coordinate point of the important tissue region, and a cross section of the spatial field strength closed body is obtained by the reference plane, wherein the surface coordinate point is located on the reference plane. If the winding number of the cross section with respect to the surface coordinate point is 1, it is determined that the surface coordinate point is in the spatial field strength closed body.

[0120] In the application, for example,Figure 13 and Figure 14 As shown, if the important tissue 131 is not completely located outside the target spatial field strength enclosure 81, a manual fine-tuning interface can be output to allow the user to adjust the orientation of the target spatial field strength enclosure 81 and adjust the ablation parameters to adjust the enclosing area of ​​each planar field strength contour line 42, that is, to adjust the enclosing range of the target spatial field strength enclosure 81, so that the target spatial field strength enclosure 81 avoids the important tissue 131, thereby avoiding ablation of the important tissue 131. In addition, the number of planar field strength contour lines extending on the main axis of the field strength body can also be changed by changing the insertion depth of the ablation needle, so as to make corresponding adjustments.

[0121] In one embodiment, the method for determining the electric field ablation region further includes: if the target planar field strength contour line does not exist, adjusting the ablation parameters to adjust the area enclosed by the planar field strength contour line until the target planar field strength contour line appears, wherein the ablation parameters include at least one of electrode needle voltage, number of ablation needles, and ablation needle spacing.

[0122] Among them, such as Figure 15 As shown, there is no target planar field strength contour line, meaning there is no spatial field strength enclosure 81 that completely surrounds the lesion area. Adjusting the ablation parameters can adjust the enclosure area of ​​each planar field strength contour line 42. For example, increasing the electrode needle voltage or increasing the number of ablation needles can increase the enclosure area of ​​each planar field strength contour line 42. Therefore, the ablation parameters can be adjusted to continuously increase the size of the spatial field strength enclosure 81 corresponding to the planar field strength contour line 42 until a spatial field strength enclosure 81 that completely surrounds the lesion area appears. The planar field strength contour line corresponding to this spatial field strength enclosure 81 is the target planar field strength contour line. The determination method described in the above embodiment can be used to detect whether the spatial field strength enclosure completely surrounds the lesion area, which will not be repeated here.

[0123] In one embodiment, the method for determining the electric field ablation region further includes: adjusting ablation parameters to adjust the size of the target spatial field strength enclosure until the distance between the target spatial field strength enclosure and the nearest surface coordinate point is within a preset range, wherein the ablation parameters include at least one of electrode needle voltage, number of ablation needles, and ablation needle spacing.

[0124] Among them, the minimum distance between the surface coordinate point and each surface of the target spatial field strength closed body is the distance between the two.

[0125] In this embodiment, the encirclement range of the target spatial field strength enclosure can be reduced by adjusting the ablation parameters. When the distance between the target spatial field strength enclosure and the nearest surface coordinate point is within a preset range, the target spatial field strength enclosure can encircle the lesion area while minimizing the ablation area of ​​benign tissue in the lesion area.

[0126] In one embodiment, the mapping of each planar field intensity contour line to the first three-dimensional model according to the first center coordinate point of the lesion region, the second center coordinate point common to each planar field intensity contour line, the first local coordinate system and the second local coordinate system comprises: obtaining a space conversion matrix by corresponding the second center coordinate point to the first center coordinate point and corresponding each coordinate axis of the second local coordinate system to each coordinate axis of the first local coordinate system, wherein the first coordinate axis, the second coordinate axis and the third coordinate axis of the second local coordinate system correspond to the first coordinate axis, the second coordinate axis and the third coordinate axis of the first local coordinate system respectively; and mapping each planar field intensity contour line to the first three-dimensional model according to the space conversion matrix.

[0127] Specifically, the first center coordinate point is converted to the corresponding point of the first local coordinate system as the second center coordinate point, a positioning point of space translation is determined, each coordinate axis of the second local coordinate system is corresponding to each coordinate axis of the first local coordinate system, a space translation direction is determined, and each planar field intensity contour line is translated into the first three-dimensional model, so as to facilitate the judgment of whether each candidate planar field intensity contour line encloses the lesion region.

[0128] Based on the above embodiments, in one embodiment, as shown in Figure 16 The application also provides a method for determining an electric field ablation region, comprising:

[0129] S1601: establishing a first three-dimensional model of a lesion region;

[0130] S1602: establishing a first local coordinate system of the lesion region by principal component analysis according to the first three-dimensional model;

[0131] S1603: obtaining each planar field intensity contour line in a reference plane, establishing a second local coordinate system by taking the normal line of the reference plane as a first coordinate axis, and taking a first vector and a second vector perpendicular to each other in the reference plane as a second coordinate axis and a third coordinate axis respectively, wherein the reference plane is an arbitrary plane;

[0132] S1604: mapping each planar field intensity contour line to the first three-dimensional model according to the first center coordinate point common to each planar field intensity contour line, the second center coordinate point of the lesion region, the first local coordinate system and the second local coordinate system;

[0133] S1605: obtaining the maximum projection value and the minimum projection value of each surface coordinate point of the first three-dimensional model on the principal coordinate axis of the first local coordinate system;

[0134] S1606: constructing a spatial field strength closed body corresponding to each of the plane field strength contour lines according to the maximum projection value, the minimum projection value, and each of the plane field strength contour lines;

[0135] S1607: if the number of intersection points of a ray along any direction of each of the surface coordinate points and the spatial field strength closed body is an odd number, determining that the spatial field strength closed body encloses each of the first three-dimensional models;

[0136] S1608: obtaining each candidate plane field strength contour line, a spatial field strength closed body obtained by extending each of the candidate plane field strength contour lines along a main axis direction of the first local coordinate system enclosing the first three-dimensional model, and the main coordinate axis direction being parallel to the ablation needle insertion direction;

[0137] S1609: determining the plane field strength contour line with the smallest enclosed area among each of the candidate plane field strength contour lines as the target plane field strength contour line, and the spatial electric field ablation region corresponding to the target plane field strength contour line being a target electric field ablation region;

[0138] S1610: if there is no candidate plane field strength contour line, adjusting the ablation parameters to adjust the enclosed area of each plane field strength contour line until the target plane field strength contour line appears, wherein the ablation parameters include at least one of the electrode needle voltage, the number of ablation needles, and the ablation needle spacing;

[0139] S1611: establishing a second three-dimensional model of important tissues located around the lesion region;

[0140] S1612: according to the first three-dimensional model and the second three-dimensional model, if each of the important tissues is not completely located outside the target spatial field strength closed body, adjusting the position and the ablation parameters of the target spatial field strength closed body until the important tissues are completely located outside the target spatial field strength closed body.

[0141] The above-mentioned electric field ablation region determination method, by obtaining the planar field strength contour in the reference plane, only needs to calculate the two-dimensional planar field strength contour, greatly saving the time for calculating the field strength contour; after establishing the first local coordinate system of the lesion region and the second local coordinate system of the reference plane, the planar field strength contour is mapped to the first three-dimensional model according to the first center coordinate point of the lesion region, the common second center coordinate point of each planar field strength contour, the first local coordinate system and the second local coordinate system, so that it can be accurately judged whether the spatial field strength closed body obtained by extending each planar field strength contour along the main coordinate axis direction of the first local coordinate system can surround the lesion region, and then the target spatial field strength closed body and the target planar field strength contour corresponding thereto are determined; in the case where the target planar field strength contour does not exist, the ablation parameters can be adjusted to continuously increase the size of the spatial field strength closed body corresponding to the planar field strength contour, until the spatial field strength closed body completely surrounding the lesion region appears, and the planar field strength contour corresponding to the spatial field strength closed body is the target planar field strength contour; since the spatial electric field ablation region corresponding to the target planar field strength contour is the target electric field ablation region, the finally determined target electric field ablation region can completely ablate the lesion region and has the smallest ablation range. In addition, in the case where the important tissue is not completely located outside the target spatial field strength closed body, the surrounding area of each planar field strength contour is adjusted by adjusting the ablation parameters, that is, the surrounding range of the target spatial field strength closed body is adjusted, so that the target spatial field strength closed body can avoid the important tissue to avoid ablation of the important tissue.

[0142] It should be understood that, although each step in the flowchart involved in each of the above-mentioned embodiments is displayed in sequence according to the arrow, these steps are not necessarily executed in sequence according to the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, at least part of the steps in the flowchart involved in each of the above-mentioned embodiments can include multiple steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or stages.

[0143] Based on the same inventive concept, the embodiments of the present application also provide an electric field ablation region determination device for implementing the above-mentioned electric field ablation region determination method. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above-mentioned method, and therefore the specific limitations in one or more electric field ablation region determination device embodiments provided below can refer to the limitations of the electric field ablation region determination method described above, which will not be repeated here.

[0144] In one embodiment, as shown in FIG. 17, an electric field ablation region determination apparatus 170 is provided, comprising a first establishing module 1701, a second establishing module 1702, a third establishing module 1703, a mapping module 1704 and a determination module 1705, wherein: Figure 17

[0145] The first establishing module 1701 is configured to establish a first three-dimensional model of a lesion region.

[0146] The second establishing module 1702 is configured to establish a first local coordinate system of the lesion region according to the first three-dimensional model.

[0147] The third establishing module 1703 is configured to obtain each plane field strength contour in a reference plane, and establish a second local coordinate system of the reference plane, wherein the reference plane is an arbitrary plane.

[0148] The mapping module 1704 is configured to map each plane field strength contour to the first three-dimensional model according to a first center coordinate point of the lesion region, a common second center coordinate point of each plane field strength contour, the first local coordinate system and the second local coordinate system.

[0149] The determination module 1705 is configured to obtain a target plane field strength contour, wherein a target spatial field strength closed body obtained by extending the target plane field strength contour along a main coordinate axis direction of the first local coordinate system encloses the first three-dimensional model, the main coordinate axis direction is parallel to a needle insertion direction of an ablation needle, and a spatial electric field ablation region corresponding to the target plane field strength contour is a target electric field ablation region.

[0150] In one embodiment, the determination module 1705 comprises:

[0151] A first obtaining unit is configured to obtain each candidate plane field strength contour, wherein a spatial field strength closed body obtained by extending each candidate plane field strength contour along a main axis direction of the first local coordinate system encloses the first three-dimensional model.

[0152] A first determination unit is configured to determine a plane field strength contour with the smallest enclosed area among each candidate plane field strength contour as the target plane field strength contour.

[0153] In one embodiment, the electric field ablation region determination apparatus 170 further comprises:

[0154] A first obtaining module is configured to obtain a maximum projection value and a minimum projection value of each surface coordinate point of the first three-dimensional model on a main coordinate axis of the first local coordinate system.

[0155] ​The constructing module is configured to construct a spatial field strength closed body corresponding to each of the plane field strength contour lines according to the maximum projection value, the minimum projection value, and the plane field strength contour lines.

[0156] In one embodiment, the electric field ablation region determining apparatus 170 further comprises:

[0157] The first determining module is configured to determine that the spatial field strength closed body encloses the first three-dimensional model when the number of intersection points of a ray in any direction of each of the surface coordinate points and the spatial field strength closed body is odd.

[0158] In one embodiment, the electric field ablation region determining apparatus 170 further comprises:

[0159] The second obtaining module is configured to obtain a reference plane based on a surface coordinate point, and obtain a cross section of the spatial field strength closed body intercepted by the reference plane, wherein the surface coordinate point is located on the reference plane.

[0160] The second determining module is configured to determine that the surface coordinate point is inside the spatial field strength closed body when the number of windings of the contour line of the cross section with respect to the surface coordinate point is 1.

[0161] The third determining module is configured to determine that the spatial field strength closed body encloses the first three-dimensional model when it is determined that each of the surface coordinate points is inside the spatial field strength closed body.

[0162] In one embodiment, the electric field ablation region determining apparatus 170 further comprises:

[0163] The first establishing module is configured to establish a second three-dimensional model of important tissues located around the lesion region.

[0164] The first adjusting module is configured to adjust the position and ablation parameters of the target spatial field strength closed body until the important tissues are completely located outside the target spatial field strength closed body when it is determined that each of the important tissues is not completely located outside the target spatial field strength closed body according to the first three-dimensional model and the second three-dimensional model, wherein the ablation parameters include at least one of an electrode needle voltage, an ablation needle number, and an ablation needle spacing.

[0165] In one embodiment, the electric field ablation region determining apparatus 170 further comprises:

[0166] The second adjusting module is configured to adjust the ablation parameters to adjust the enclosed area of each of the plane field strength contour lines until the target plane field strength contour line appears when the target plane field strength contour line does not exist, wherein the ablation parameters include at least one of an electrode needle voltage, an ablation needle number, and an ablation needle spacing.

[0167] In one embodiment, the electric field ablation region determining apparatus 170 further comprises:

[0168] a third adjusting module, configured to adjust an ablation parameter to adjust a size of the target space field strength enclosure until a distance between the target space field strength enclosure and the closest surface coordinate point is within a preset range, wherein the ablation parameter comprises at least one of an electrode needle voltage, a number of ablation needles, and an ablation needle spacing.

[0169] In one embodiment, the second establishing module 1702 comprises:

[0170] a fourth obtaining unit, configured to obtain a covariance matrix of the lesion region according to each surface coordinate point of the first three-dimensional model and the first center coordinate point;

[0171] a characteristic decomposition unit, configured to perform eigenvalue decomposition on the covariance matrix to obtain a maximum eigenvector and a second maximum eigenvector as a first coordinate axis and a second coordinate axis of the first local coordinate system, wherein the first coordinate axis is a principal coordinate axis of the first local coordinate system;

[0172] a cross product unit, configured to perform cross product on the maximum eigenvector and the second maximum eigenvector to obtain a third coordinate axis of the first local coordinate system.

[0173] In one embodiment, the third establishing module 1703 comprises:

[0174] an establishing unit, configured to establish the second local coordinate system by taking a normal of the reference surface as a first coordinate axis, and taking a first vector and a second vector in the reference surface and perpendicular to each other as a second coordinate axis and a third coordinate axis respectively.

[0175] In one embodiment, the mapping module 1704 comprises:

[0176] a second obtaining unit, configured to obtain a space conversion matrix by taking the second center coordinate point corresponding to the first center coordinate point and each coordinate axis of the second local coordinate system corresponding to each coordinate axis of the first local coordinate system, wherein the first coordinate axis, the second coordinate axis, and the third coordinate axis of the second local coordinate system correspond to the first coordinate axis, the second coordinate axis, and the third coordinate axis of the first local coordinate system respectively;

[0177] a mapping unit, configured to map each plane field strength contour line on the first three-dimensional model according to the space conversion matrix.

[0178] Each of the modules in the above electric field ablation region determination apparatus can be implemented by software, hardware, and combinations thereof, in whole or in part. The modules can be embedded in or independent of a processor in a computer device in hardware form, or stored in a memory in a computer device in software form, so as to be invoked by a processor to perform operations corresponding to the modules.

[0179] In one embodiment, a computer device is provided, which can be a terminal, and an internal structure diagram thereof can be as shown in Figure 18 The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit, and an input device. The processor, the memory, and the input / output interface are connected through a system bus, and the communication interface, the display unit, and the input device are connected to the system bus through the input / output interface. The processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for running of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is configured to exchange information between the processor and external devices. The communication interface of the computer device is configured to perform wired or wireless communication with external terminals, and the wireless communication can be achieved through WIFI, mobile cellular network, NFC (near field communication), or other technologies. The computer program is executed by the processor to implement an electric field ablation region determination method. The display unit of the computer device is configured to form a visually visible picture, which can be a display screen, a projection device, or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer surrounding the display screen, or a key, a trackball, or a touchpad arranged on the shell of the computer device, or an external keyboard, a touchpad, a mouse, or the like.

[0180] Those skilled in the art can understand that Figure 18 The structure shown in the above embodiment is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. Specifically, the computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0181] In one embodiment, a computer device is provided, which includes a memory and a processor, and the memory stores a computer program. The processor executes the computer program to implement the steps of the electric field ablation region determination method according to any one of the above embodiments.

[0182] In one embodiment, a computer readable storage medium is provided, and a computer program is stored on the computer readable storage medium, and the computer program is executed by a processor to implement the steps of the electric field ablation region determination method according to any one of the above embodiments.

[0183] In one embodiment, a computer program product is provided, and the computer program product comprises a computer program, and the computer program is executed by a processor to implement the steps of the electric field ablation region determination method according to any one of the above embodiments.

[0184] It should be noted that the user information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the present application are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of related data need to comply with relevant laws, regulations and standards of relevant countries and regions.

[0185] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when the computer program is executed, the processes of the above-mentioned embodiments of the methods can be included. Any reference to memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (Read-Only Memory, ROM), magnetic tape, floppy disk, flash memory, optical storage, high-density embedded non-volatile memory, resistive memory (ReRAM), magnetoresistive random access memory (Magnetoresistive Random Access Memory, MRAM), ferroelectric memory (Ferroelectric Random Access Memory, FRAM), phase change memory (Phase Change Memory, PCM), graphene memory, etc. Volatile memory can include random access memory (Random Access Memory, RAM) or external cache memory, etc. As an illustration but not limitation, RAM can be in various forms, such as static random access memory (Static Random Access Memory, SRAM) or dynamic random access memory (Dynamic Random Access Memory, DRAM), etc. The database involved in the embodiments provided in the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in the embodiments provided in the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., without being limited thereto.

[0186] Any combination of the technical features of the above embodiments can be made. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0187] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. An electric field ablation zone determination apparatus, characterized by, The device comprises: A first establishing module for establishing a first three-dimensional model of a lesion area; A second establishing module for establishing a first local coordinate system of the lesion area according to the first three-dimensional model; A third establishing module for obtaining each plane field strength contour in a reference plane, and establishing a second local coordinate system of the reference plane, wherein the reference plane is an arbitrary plane; A mapping module for mapping each plane field strength contour on the first three-dimensional model according to a first center coordinate point of the lesion area, a common second center coordinate point of each plane field strength contour, the first local coordinate system, and the second local coordinate system; A determining module for obtaining a target plane field strength contour, wherein a target spatial field strength closed body obtained by extending the target plane field strength contour along a main coordinate axis direction of the first local coordinate system encloses the lesion area, the main coordinate axis direction is parallel to an ablation needle insertion direction, and a spatial electric field ablation area corresponding to the target plane field strength contour is a target electric field ablation area; The determining module comprises: a first obtaining unit for obtaining each candidate plane field strength contour, wherein a spatial field strength closed body obtained by extending each candidate plane field strength contour along a main axis direction of the first local coordinate system encloses the first three-dimensional model; and a first determining unit for determining a plane field strength contour with the smallest enclosed area among each candidate plane field strength contour as the target plane field strength contour; The second establishing module comprises: a fourth obtaining unit for obtaining a covariance matrix of the lesion area according to each surface coordinate point of the first three-dimensional model and the first center coordinate point; an eigenvalue decomposition unit for performing eigenvalue decomposition on the covariance matrix to obtain a maximum eigenvector and a second maximum eigenvector as a first coordinate axis and a second coordinate axis of the first local coordinate system, wherein the first coordinate axis is a main coordinate axis of the first local coordinate system; and a cross product unit for performing cross product on the maximum eigenvector and the second maximum eigenvector to obtain a third coordinate axis of the first local coordinate system; The third establishing module comprises: an establishing unit for establishing the second local coordinate system by taking a normal line of the reference plane as a first coordinate axis, and taking a first vector and a second vector that are perpendicular to each other in the reference plane as a second coordinate axis and a third coordinate axis, respectively; The mapping module comprises: a second obtaining unit for obtaining a spatial conversion matrix corresponding to the second center coordinate point and the first center coordinate point, and corresponding to each coordinate axis of the second local coordinate system and each coordinate axis of the first local coordinate system, wherein the first coordinate axis, the second coordinate axis, and the third coordinate axis of the second local coordinate system correspond to the first coordinate axis, the second coordinate axis, and the third coordinate axis of the first local coordinate system, respectively; and a mapping unit for mapping each plane field strength contour on the first three-dimensional model according to the spatial conversion matrix.

2. The electric field ablation region determination apparatus according to claim 1, wherein The electric field ablation area determination device further comprises: A first obtaining module for obtaining a maximum projection value and a minimum projection value of each surface coordinate point of the first three-dimensional model on a main coordinate axis of the first local coordinate system; The constructing module is configured to construct a spatial field strength closed body corresponding to each of the planar field strength contour lines according to the maximum projection value, the minimum projection value, and the planar field strength contour lines.

3. The electric field ablation region determination apparatus of claim 2, wherein, The electric field ablation region determination apparatus further comprises: The first determining module is configured to determine that the spatial field strength closed body encloses the first three-dimensional model when the number of intersection points of a ray in any direction of each of the surface coordinate points and the spatial field strength closed body is odd.

4. The electric field ablation zone determination apparatus of claim 2, wherein, The electric field ablation region determination apparatus further comprises: The second obtaining module is configured to obtain a reference plane based on a surface coordinate point, and obtain a cross section of the spatial field strength closed body intercepted by the reference plane, wherein the surface coordinate point is located on the reference plane. The second determining module is configured to determine that the surface coordinate point is inside the spatial field strength closed body when the number of windings of the contour line of the cross section with respect to the surface coordinate point is 1. The third determining module is configured to determine that the spatial field strength closed body encloses the first three-dimensional model when it is determined that each of the surface coordinate points is inside the spatial field strength closed body.

5. The electric field ablation zone determination apparatus of claim 1, wherein, The electric field ablation region determination apparatus further comprises: The first establishing module is configured to establish a second three-dimensional model of important tissues located around the lesion region. The first adjusting module is configured to adjust the position and ablation parameters of the target spatial field strength closed body until the important tissues are completely located outside the target spatial field strength closed body when it is determined that each of the important tissues is not completely located outside the target spatial field strength closed body according to the first three-dimensional model and the second three-dimensional model, wherein the ablation parameters include at least one of an electrode needle voltage, an ablation needle number, and an ablation needle spacing.

6. The electric field ablation zone determination apparatus of claim 1, wherein, The electric field ablation region determination apparatus further comprises: The second adjusting module is configured to adjust the ablation parameters to adjust the enclosed area of each of the planar field strength contour lines until the target planar field strength contour line appears when the target planar field strength contour line does not exist, wherein the ablation parameters include at least one of an electrode needle voltage, an ablation needle number, and an ablation needle spacing.

7. The electric field ablation zone determination apparatus of claim 1, wherein, The electric field ablation region determination apparatus further comprises: The third adjusting module is configured to adjust the ablation parameters to adjust the size of the target spatial field strength closed body until the distance between the target spatial field strength closed body and the closest surface coordinate point is within a preset range, wherein the ablation parameters include at least one of an electrode needle voltage, an ablation needle number, and an ablation needle spacing.

Images