Registration method and device

Abstract

The invention provides a registration method and device. According to the method, a source polygon is selected from a registration point set acquired by second medical equipment, and a target polygon corresponding to the source polygon is acquired according to a side length difference range, so that a first conversion matrix is acquired, and initial conversion of coordinate systems of the registration point set and a target point set is realized. In order to improve registration accuracy, the method comprises the following steps: determining a point pair relationship between coordinates in a registration point set and coordinates in a target point set at least according to a first conversion matrix to form a point pair set; and obtaining a second conversion matrix according to the point pair set. Furthermore, according to the method, a verification point set is adopted to verify the matching degree of the second conversion matrix, and conversion errors are converged to be within a preset range through repeated screening, so that the second conversion matrix with better registration accuracy is obtained. Therefore, according to the registration method and device provided by the invention, the markers do not need to be registered one by one in sequence, automatic and efficient registration is realized, and the registration precision is high.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a registration method and device. Background Art

[0002] The surgical robot is a medical device that integrates a number of modern high-tech means, with the advantages of high precision and low trauma. At this stage, surgical robots mainly assist doctors in performing surgical operations and have become increasingly popular. Among them, the surgical robot needs to complete spatial registration with the medical imaging device before the operation. That is, the correspondence between the spatial coordinates in the medical imaging device system and the coordinates of the patient in the physical space is obtained, and the registration of the surgical robot and the medical imaging device is completed through the correspondence, so that the surgical robot can accurately navigate to the target position of the patient.

[0003] The existing registration scheme requires attaching multiple markers on the patient's body and registering them one by one in a fixed order. In the registration process, the doctor needs to strictly follow the order on the display screen to obtain the position of the markers in the surgical space one by one. The doctor needs to repeatedly switch his sight between the display screen and the patient, resulting in low efficiency of intraoperative registration. In addition, if the doctor does not obtain the positions of the markers one by one in the corresponding order, it will directly lead to registration failure.

[0004] Therefore, a new registration method is urgently needed to solve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a registration method and device to solve the problem of how to improve the efficiency and accuracy of coordinate conversion between medical devices.

[0006] In order to solve the above technical problems, the present invention provides a registration method for coordinate registration between medical devices, comprising:

[0007] Step 1: Install multiple markers at corresponding target locations at intervals;

[0008] Step 2: using a first medical device to obtain the coordinates of each of the markers to form a target point set; using a second medical device to obtain the coordinates of some of the markers to form a registration point set;

[0009] Step 3: selecting at least three coordinate points of the markers in the registration point set to form a source polygon; and forming a plurality of target polygons from the coordinate points of each marker in the target point set;

[0010] Step 4: traverse and compare the side lengths of each of the target polygons and the source polygons, and obtain the target polygons that meet the side length difference range to form a target polygon set;

[0011] Step 5: Obtain a first transformation matrix according to the source polygon and the target polygon set;

[0012] Step six: determining the point pair relationship between the coordinates of the marker in the registration point set and the coordinates of the marker in the target point set at least according to the first transformation matrix, and forming a point pair set;

[0013] Step 7: Obtain a second transformation matrix according to the point pair set;

[0014] Step 8: using the second medical device to obtain the coordinates of the remaining markers to form a verification point set;

[0015] Step nine: Use the second transformation matrix to transform the coordinates of the markers in the verification point set, and determine whether the transformation error is within a preset range. If so, use the second transformation matrix to perform coordinate alignment between the first medical device and the second medical device; if not, repeat steps two to eight until the transformation error is within a preset range.

[0016] Optionally, in the registration method, the source polygon and each of the target polygons have the same number of vertices.

[0017] Optionally, in the registration method, in step three, three coordinate points of the markers are selected from the registration point set to form a source triangle; and all coordinate points of the markers in the target point set are arranged into multiple target triangles.

[0018] Optionally, in the alignment method, in step four and step five, the side lengths of each target triangle and the source triangle are traversed and compared, and the target triangles that meet the side length difference range are obtained to form the target polygon set; and, based on the source triangle and the target polygon set, the first transformation matrix is ​​obtained.

[0019] Optionally, in the registration method, in step six, the coordinates of each vertex of the source polygon in the registration point set are removed, and the coordinates of the remaining markers in the registration point set are transformed using the first transformation matrix to form a transformation point set;

[0020] The coordinate points in the target point set that belong to the target polygon set are removed, and the distance between each coordinate point in the conversion point set and each remaining coordinate point in the target point set is obtained, and the coordinate point in the target point set with the smallest distance is used as the pairing point of the corresponding coordinate point in the conversion point set;

[0021] According to the pairing points of each coordinate point in the conversion point set, the source polygon and the target polygon set, the point pair relationship between the coordinates of the marker in the registration point set and the coordinates of the marker in the target point set is determined, and the point pair set is formed.

[0022] Optionally, in the registration method, in step one, the number of the markers is greater than or equal to 4, and any three of the markers are not collinear, and any four of the markers are not coplanar.

[0023] Optionally, in the registration method, in step 2, the number of coordinates of the markers acquired by the second medical device is greater than or equal to 3, and any three acquired markers are not collinear.

[0024] Optionally, in the registration method, the first medical device includes a computer tomography device or a magnetic resonance device; the second medical device includes a surgical robot or an infrared laser positioning device.

[0025] Optionally, in the alignment method, the second medical device is an infrared laser positioning device, and after step nine, the alignment method further includes: using a target to convert the coordinate system of the surgical robot into the coordinate system of the infrared laser positioning device to enable coordinate alignment between the surgical robot and the first medical device.

[0026] Based on the same inventive concept, the present invention also provides a registration device, comprising:

[0027] A data storage module, for storing at least the coordinates of each marker acquired by the first medical device to form a target point set; the coordinates of some of the markers acquired by the second medical device to form a registration point set; and the coordinates of the remaining markers acquired by the second medical device to form a verification point set;

[0028] A coordinate matching module is used to select at least three coordinate points of the markers in the registration point set to form a source polygon; the coordinate points of each marker in the target point set are used to form a plurality of target polygons; traverse and compare the side lengths of each target polygon with the source polygon, and obtain the target polygons that meet the side length difference range to form a target polygon set; and obtain a first transformation matrix according to the source polygon and the target polygon set;

[0029] A coordinate registration module, configured to determine, at least according to the first transformation matrix, a point pair relationship between the coordinates of the marker in the registration point set and the coordinates of the marker in the target point set, and form a point pair set; and, according to the point pair set, obtain a second transformation matrix;

[0030] A registration verification module is used to use the second transformation matrix to transform the coordinates of the markers in the verification point set, and determine whether the transformation error is within a preset range. If so, the second transformation matrix is ​​used to perform coordinate registration between the first medical device and the second medical device; if not, the data storage module, the coordinate matching module and the coordinate registration module are repeatedly operated in sequence until the transformation error is within a preset range.

[0031] In summary, the present invention provides a registration method and device. The method randomly selects a source polygon from the registration point set acquired by the second medical device, and acquires a target polygon in the target point set corresponding to the source polygon according to a preset side length difference range, thereby acquiring a first transformation matrix, realizing the initial transformation of the coordinate system corresponding to the registration point set and the target point set, without paying attention to the order of the markers. To improve the registration accuracy, the method at least determines the point pair relationship between the coordinates of the markers in the registration point set and the coordinates of the markers in the target point set according to the first transformation matrix, and forms a point pair set; and, according to the point pair set, acquires a second transformation matrix. Furthermore, the method also uses the verification point set to verify the matching accuracy of the second transformation matrix, and after repeated screening, converges the conversion error to a preset range, thereby acquiring the second transformation matrix with better accuracy, realizing the automatic registration of coordinates between the first medical device and the second medical device. Therefore, the registration method and device provided by the present invention do not need to register the markers one by one in sequence, and thus achieve automatic and efficient registration between medical devices with high registration accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Those skilled in the art will appreciate that the accompanying drawings are provided for a better understanding of the present invention and do not constitute any limitation on the scope of the present invention.

[0033] Figure 1 4 is a flow chart of the registration method in an embodiment of the present invention.

[0034] Figure 2 Schematic diagram of the distribution of markers in the embodiment of the present invention.

[0035] Figure 3 Schematic diagram of the structure of the first medical device and the second medical device in an embodiment of the present invention.

[0036] Figure 4 Schematic diagram of a target point set in an embodiment of the present invention.

[0037] Figure 5Schematic diagram of a set of registration points in an embodiment of the present invention.

[0038] Figure 6 Schematic diagram of a target polygon set in an embodiment of the present invention.

[0039] Figure 7 Schematic diagram of a set of conversion points in an embodiment of the present invention.

[0040] Figure 8 Schematic diagram of a point pair set in an embodiment of the present invention.

[0041] Fig. 9 Schematic diagram of a verification point set in an embodiment of the present invention.

[0042] Fig.10 Schematic diagram of a registration device in an embodiment of the present invention.

[0043] In the attached figure:

[0044] 10-first medical equipment; 20-second medical equipment; 30-surgical robot;

[0045] 100-data storage module; 200-coordinate matching module; 300-coordinate registration module; 400-registration verification module;

[0046] M-marker; M1-first marker; M2-second marker; M3-third marker; M4-fourth marker; M5-fifth marker; M6-sixth marker; M4'-first transition point; M5'-second transition point;

[0047] N1-target point set; N2-registration point set; N3-target polygon set; N4-conversion point set; N5-point pair set; N6-verification point set;

[0048] P1 - source triangle; P2 - target triangle. DETAILED DESCRIPTION

[0049] In order to make the purpose, advantages and features of the present invention clearer, the present invention is further described in detail in conjunction with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In addition, the structure shown in the drawings is often a part of the actual structure. In particular, the emphasis of each drawing is different, and sometimes different proportions are used. It should also be understood that, unless otherwise specified or indicated, the terms "first", "second", "third" and the like in the specification are only used to distinguish the various components, elements, steps, etc. in the specification, rather than to represent the logical relationship or sequential relationship between the various components, elements, steps, etc. And, the XYZ coordinate system referred to in the specification of this application is the image coordinate system of the first medical device; the xyz coordinate system is the physical coordinate system of the second medical device.

[0050] See also Figure 1 This embodiment provides a registration method for realizing coordinate registration between medical devices, including:

[0051] Step 1 S10: installing a plurality of markers at intervals at corresponding target positions;

[0052] Step 2 S20: using the first medical device to obtain the coordinates of each of the markers to form a target point set; using the second medical device to obtain the coordinates of some of the markers to form a registration point set;

[0053] Step 3 S30: selecting at least three coordinate points of the markers in the registration point set to form a source polygon; and forming a plurality of target polygons from the coordinate points of each marker in the target point set;

[0054] Step 4 S40: traversing and comparing the side lengths of each of the target polygons and the source polygons, and obtaining the target polygons that meet the side length difference range to form a target polygon set;

[0055] Step 5 S50: acquiring a first transformation matrix according to the source polygon and the target polygon set;

[0056] Step six S60: determining the point pair relationship between the coordinates of the marker in the registration point set and the coordinates of the marker in the target point set at least according to the first transformation matrix, and forming a point pair set;

[0057] Step 7 S70: Obtain a second transformation matrix according to the point pair set;

[0058] Step eight S80: using the second medical device to obtain the coordinates of the remaining markers to form a verification point set;

[0059] Step nine S90: Use the second transformation matrix to transform the coordinates of the markers in the verification point set, and determine whether the transformation error is within a preset range. If so, use the second transformation matrix to perform coordinate alignment between the first medical device and the second medical device; if not, repeat steps two S20 to eight S80 until the transformation error is within a preset range.

[0060] It can be understood that the method provided in this embodiment is to randomly select a source polygon from the set of registration points acquired by the second medical device, and obtain a target polygon in the target point set corresponding to the source polygon according to a preset side length difference range, thereby obtaining a first transformation matrix, realizing the initial transformation of the coordinate system corresponding to the registration point set and the target point set, without paying attention to the order of the markers. In order to improve the registration accuracy, the method determines the point pair relationship between the coordinates of the markers in the registration point set and the coordinates of the markers in the target point set at least according to the first transformation matrix, and forms a point pair set; and, according to the point pair set, obtains a second transformation matrix. Further, the method also uses the verification point set to verify the matching accuracy of the second transformation matrix, and after repeated screening, converges the conversion error to a preset range, thereby obtaining the second transformation matrix with better accuracy, realizing the automatic registration of coordinates between the first medical device and the second medical device. Therefore, the registration method provided in this embodiment does not need to register the markers one by one in sequence, and realizes automatic and efficient registration between medical devices with high registration accuracy.

[0061] The following is combined with Figures 1 to 9 The registration method provided in this embodiment is described in detail.

[0062] Step 1 S10: Please refer to Figure 2 , multiple markers M are installed at intervals at corresponding target positions.

[0063] It should be noted that in the field of medical devices, the marker M is generally used as a basis for positioning and navigation of the device. The marker M is a small component with a shape mark and / or a material mark, which can be easily positioned and identified by medical equipment through imaging or infrared technology.

[0064] Furthermore, the number of the markers M in this embodiment is greater than or equal to 4, and any three of the markers M are not collinear, and any four of the markers M are not coplanar, so as to ensure that the multiple markers M can fully characterize the three-dimensional characteristics of the detection object.

[0065] Step 2 S20: Please refer to Figures 3 to 5, the first medical device 10 is used to obtain the coordinates of each of the markers M to form a target point set N1; the second medical device 20 is used to obtain the coordinates of some of the markers M to form a registration point set N2.

[0066] Exemplarily, the first medical device 10 is used to obtain medical images during surgery, such as a computer tomography (CT), a magnetic resonance imaging (MRI) or a digital subtraction angiography (DSA). The second medical device 20 can be an infrared laser positioning device, and is equipped with a probe for obtaining the coordinates of the physical space of the detection object. It should be noted that the infrared laser positioning device is only used to realize the positioning of the detection object during surgery, so the infrared laser positioning device also needs to be consistent with the coordinate system of other medical devices. For example, the coordinate system of the surgical robot 30 is converted into the coordinate system of the infrared laser positioning device through a target to achieve the unification of the coordinate systems of the two. Further, if the surgical robot 30 is equipped with a positioning acquisition function, the second medical device 20 can be directly the surgical robot 30. Alternatively, the second medical device 20 is a medical device with a positioning acquisition function.

[0067] Furthermore, the first medical device 10 acquires the coordinates of all the markers M to form the target point set N1. The second medical device 20 may randomly acquire the coordinates of some of the markers M for registration calculation. Preferably, the number of the markers M acquired by the second medical device 20 is greater than or equal to 3, and any three of the markers M are not collinear, so as to be able to be combined into the most basic polygonal structure.

[0068] Exemplarily, six markers M are arranged on the detection object, namely: a first marker M1, a second marker M2, a third marker M3, a fourth marker M4, a fifth marker M5 and a sixth marker M6. The first medical device 10 obtains the coordinates of all the markers M, and then forms the target point set N1 = [M1 (X1, Y1, Z1), M2 (X2, Y2, Z2), M3 (X3, Y3, Z3), M4 (X4, Y4, Z4), M5 (X5, Y5, Z5), M6 (X6, Y6, Z6)]. The second medical device 20 obtains the coordinates of five of the markers M as registration marks, thereby forming the registration point set N2 = [M1 (x1, y1, z1), M2 (x2, y2, z2), M3 (x3, y3, z3), M4 (x4, y4, z4), M5 (x5, y5, z5)]. It can be understood that the coordinates of each of the markers M obtained by the first medical device 10 are based on its own image coordinate system, and the coordinates of each of the markers M obtained by the second medical device 20 are also based on its own physical coordinate system. Since the coordinate systems of the first medical device 10 and the second medical device 20 are not exactly the same, it is necessary to convert the coordinates between the two to perform surgery in the same coordinate system, ensure the accuracy of the surgery, and improve the success rate of the surgery.

[0069] Preferably, the coordinates of the marker M acquired by the first medical device 10 and the second medical device 20 are the three-dimensional coordinates of the center point of the marker M.

[0070] Step 3 S30: Please continue to read Figures 3 to 5 , selecting at least three coordinate points of the marker M in the registration point set N2 to form a source polygon; and, forming a plurality of target polygons with the coordinate points of each marker M in the target point set N1.

[0071] It can be understood that the present embodiment uses a polygonal structure as the basic model for coordinate matching to achieve the initial matching of the coordinate points of the registration point set N2 and the target point set N1, without paying attention to the serial number of a single marker M. Furthermore, the source polygon and each of the target polygons have the same number of vertices, for example, they are all triangles, quadrilaterals or pentagons. Since the triangle is the most basic polygonal model and has a smaller amount of calculation than structures such as quadrilaterals or pentagons, the present embodiment preferably configures the source polygon to be a triangle. Based on this, in step three S30, three coordinate points of the marker M are randomly selected from the registration point set N2 to form a source triangle P1; and, the coordinate points of all the markers M in the target point set N1 are arranged into multiple target triangles P2.

[0072] Exemplarily, a first marker M1 (x1, y1, z1), a second marker M2 (x2, y2, z2) and a third marker M3 (x3, y3, z3) are selected from the registration point set N2 to form the source triangle P1. And, the six markers M in the target point set N1 are arranged as It can be understood that the same three points in the target point set N1 can constitute six different target triangles P2.

[0073] Step 4 S40: Please refer to Figures 4 to 6 , traverse and compare the side lengths of each of the target polygons and the source polygons, and obtain the target polygons that meet the side length difference range to form a target polygon set N3.

[0074] It can be understood that, since the target polygons are obtained by arrangement, the vertices of each target polygon can correspond one-to-one with the vertices of the source polygon. Therefore, when comparing the side lengths of the target polygon and the source polygon, the corresponding side lengths are compared by difference. And when the side length difference of each side of the target polygon is within the preset side length difference range, the target polygon is considered to meet the side length difference range. Preferably, a target polygon with the smallest side length difference is selected as the target polygon deformation that meets the side length difference range of the source polygon, and the coordinates of each vertex in the target polygon form the target polygon set N3. Further, since in the process of side length difference screening, the vertices of each target polygon correspond one-to-one with the vertices of the source polygon, the coordinates of each vertex in the target polygon set N3 also correspond to each vertex of the source polygon. Thus, the coordinates of each vertex in the source polygon are determined relative to the matching points in the target point set N1.

[0075] Exemplarily, the side lengths of the 120 target triangles P2 in the target point set N1 are compared one by one with those of the source triangle P1. Assuming that the side length differences between the target triangle △M1M2M3 and the source triangle P1 are within a preset range, the coordinates of the three vertices in the target triangle △M1M2M3 constitute the target polygon set N3. Moreover, the three vertices in the source triangle P1 correspond one-to-one to the three vertices in the target polygon set N3, respectively, forming the following three point pair combinations: [M1(x1, y1, z1), M1(X1, Y1, Z1)], [M2(x2, y2, z2), M2(X2, Y2, Z2)] and [M3(x3, y3, z3), M3(X3, Y3, Z3)].

[0076] Step 5 S50: Please continue to read Figures 4 to 6, obtain a first transformation matrix according to the source polygon and the target polygon set N3.

[0077] Specifically, since each vertex of the source polygon and each vertex of the target polygon in the target polygon set N3 form a point pair combination, the first transformation matrix is ​​obtained according to all point pair combinations. It should be noted that the first transformation matrix represents the transformation relationship between the coordinate system where the target point set N1 is located and the coordinate system where the pairing point set N2 is located, which can be the transformation of the registration point set N2 relative to the target point set N1, or the transformation of the target point set N1 relative to the registration point set N2, which is not specifically limited in this embodiment.

[0078] Exemplarily, the target polygon set N3 includes: target triangle △M1M2M3. The three vertices of the source triangle P1 and the three vertices of the target triangle △M1M2M3 form three point pair combinations, namely: [M1(x1, y1, z1), M1(X1, Y1, Z1)], [M2(x2, y2, z2), M2(X2, Y2, Z2)] and [M3(x3, y3, z3), M3(X3, Y3, Z3)], then according to the three point pair combinations obtained, the unified first transformation matrix is ​​calculated to realize the transformation between the coordinate system of the first medical device 10 and the coordinate system of the second medical device 20, without the need to perform one-by-one transformation according to the order of the markers M.

[0079] Step 6 S60: Please refer to Figure 1 , Figure 2 , Figure 7 and Figure 8 , at least based on the first transformation matrix, determine the point pair relationship between the coordinates of the marker M in the registration point set N2 and the coordinates of the marker M in the target point set N1, and form a point pair set N5.

[0080] Specifically, since the matching points of each vertex in the source polygon relative to the target point have been determined in the process of obtaining the first transformation matrix, in order to reduce the amount of calculation, it is not necessary to convert the coordinates of each vertex of the source polygon. Therefore, the coordinates of each vertex of the source polygon in the registration point set N2 are removed, and the coordinates of the remaining marker M in the registration point set N2 are converted using the first transformation matrix to form a transformation point set N4. It can be understood that since the first transformation matrix is ​​used to characterize the conversion relationship between the coordinate system where the target point set N1 is located and the coordinate system where the pairing point set N2 is located, the transformation point set N4 obtained in this embodiment is based on the coordinate points in the coordinate system of the first medical device 10.

[0081] For example, Figure 7 As shown, the registration point set N2 = [M1(x1, y1, z1), M2(x2, y2, z2), M3(x3, y3, z3), M4(x4, y4, z4), M5(x5, y5, z5)], after removing the three vertices of the source triangle P1: M1(x1, y1, z1), M2(x2, y2, z2), M3(x3, y3, z3), the fourth marker M4(x4, y4, z4) and the fifth marker M5(x5, y5, z5) remain. The fourth marker M4 (x4, y4, z4) and the fifth marker M5 (x5, y5, z5) are transformed using the first transformation matrix to form the transformation point set N4 = [M4'(X4', Y4', Z4'), M5'(X5', Y5', Z5')].

[0082] Furthermore, since the coordinates of each vertex of the target polygon in the target polygon set N3 are used for conversion in the process of calculating the first conversion matrix, and the vertex coordinates of the source polygon are removed in the process of obtaining the conversion point set N4, in order to reduce the amount of calculation, the coordinate points in the target point set N1 that belong to the target polygon set N3 are removed. Then, the distance between each coordinate point in the conversion point set N4 and each remaining coordinate point in the target point set N1 is obtained, and the coordinate point in the target point set N1 with the smallest distance is used as the pairing point of the corresponding coordinate point in the conversion point set N4.

[0083] Exemplarily, the conversion point set N4 = [M4'(X4', Y4', Z4'), M5'(X5', Y5', Z5')], and the target point set N1 after removing the coordinate points in the target polygon set N3 still has the following coordinate points remaining: M4(X4, Y4, Z4), M5(X5, Y5, Z5) and M6(X6, Y6, Z6)]. Based on this, for the first conversion point M4'(X4', Y4', Z4'), d1 = |M4'M4|, d2 = |M4'M5| and d3 = |M4'M6| are calculated; for the second conversion point M5'(X5', Y5', Z5'), d4 = |M5'M4|, d5 = |M5'M5| and d6 = |M5'M6| are calculated. Further, after obtaining all the spacings, the sizes of d1, d2 and d3 are determined for the first conversion point M4', and the coordinate point in the target point set N1 corresponding to the smallest spacing is selected as the pairing point of the first conversion point M4'. That is, d1 is the smallest, and the fourth mark M4 in the target point set N1 corresponding to d1 is the pairing point of the first conversion point M4'. Similarly, the sizes of d4, d5 and d6 are determined for the second conversion point M5', and d5 is the smallest, then the fifth mark M5 in the target point set N1 corresponding to d5 is the pairing point of the second conversion point M5'.

[0084] Furthermore, since the conversion point set N4 and the registration point set N2 are based on the first conversion relationship, the coordinate points in the conversion point set N4 can find corresponding coordinate points in the registration point set N2. Therefore, after obtaining all the paired points, the corresponding coordinate points can be found in the registration point set N2 according to the paired points of each coordinate point in the conversion point set N4, so as to achieve the matching of each coordinate point in the registration point set N2 except the source polygon vertex with the coordinate points in the target point set N1.

[0085] Exemplarily, the first conversion point M4'(X4', Y4', Z4') in the conversion point set N4 matches the fourth marker M4(X4, Y4, Z4) in the target point set N1, and the first conversion point M4'(X4', Y4', Z4') is converted by the fourth marker M4(x4, y4, z4) in the registration point set N2 through the first conversion matrix. Therefore, the fourth marker M4(x4, y4, z4) in the registration point set N2 matches the fourth marker M4(X4, Y4, Z4) in the target point set N1, and constitutes a point pair combination. Similarly, the second conversion point M5'(X5', Y5', Z5') in the conversion point set N4 matches the fifth mark M5(X5, Y5, Z5) in the target point set N1, and the second conversion point M5'(X5', Y5', Z5') is converted by the fifth mark M5(x5, y5, z5) in the registration point set N2 through the first conversion matrix. Therefore, the fifth mark M5(x5, y5, z5) in the registration point set N2 matches the fifth mark M5(X5, Y5, Z5) in the target point set N1, and forms a point pair combination.

[0086] Furthermore, since the source polygon corresponds to the coordinate points in the target polygon set N3, the point pair relationship between the coordinates of the marker M in the registration point set N2 and the coordinates of the marker M in the target point set N1 can be obtained to form the point pair set N5.

[0087] Exemplarily, the three vertices of the source triangle P1 and the three vertices of the target triangle △M1M2M3 form three point pair combinations, namely: [M1(x1, y1, z1), M1(X1, Y1, Z1)], [M2(x2, y2, z2), M2(X2, Y2, Z2)] and [M3(x3, y3, z3), M3(X3, Y3, Z3)]. In addition, after calculation, the fifth marker M5(x5, y5, z5) in the registration point set N2 matches the fifth marker M5(X5, Y5, Z5) in the target point set N1, and the fifth marker M5(x5, y5, z5) in the registration point set N2 matches the fifth marker M5(X5, Y5, Z5) in the target point set N1. In this way, the point pair combinations of all coordinate points in the registration point set N2 relative to the target point set N1 can be obtained, and the point pair set N5 = [M1(x1, y1, z1), M1(X1, Y1, Z1)], [M2(x2, y2, z2), M2(X2, Y2, Z2)], [M3(x3, y3, z3), M3(X3, Y3, Z3)], [M4(x4, y4, z4), M4(X4, Y4, Z4)] and [M5(x5, y5, z5), M5(X5, Y5, Z5)] are formed.

[0088] Step 7 S70: Please refer to Figure 8 , obtain a second transformation matrix according to the point pair set N5.

[0089] Exemplarily, the second transformation rectangle is calculated based on the point pair set N5 = [M1(x1, y1, z1), M1(X1, Y1, Z1)], [M2(x2, y2, z2), M2(X2, Y2, Z2)], [M3(x3, y3, z3), M3(X3, Y3, Z3)], [M4(x4, y4, z4), M4(X4, Y4, Z4)] and [M5(x5, y5, z5), M5(X5, Y5, Z5)].

[0090] It can be seen that this embodiment obtains the first transformation matrix through the matching relationship between the source polygon and the target polygon. Based on this, the transformation relationship between the coordinate system corresponding to the registration point set N2 and the coordinate system corresponding to the target point set N1 can be roughly obtained. Then, under the transformation of the first transformation matrix, the matching relationship of the remaining coordinate points in the registration point set N2 except the vertices of the source polygon relative to the target point set N1 is achieved through spacing screening, and a more accurate second transformation matrix is ​​obtained. It can be understood that the second transformation matrix is ​​also used to characterize the transformation relationship between the coordinate system where the target point set N1 is located and the coordinate system where the pairing point set N2 is located, but its accuracy is much higher than that of the first transformation matrix.

[0091] Step 8 S80: Please refer to Figure 2 and Fig. 9 , use the second medical device 20 to obtain the coordinates of the remaining markers M to form a verification point set N6.

[0092] Exemplarily, the verification point set N6 = [M6 (x6, y6, z6)].

[0093] Step 9 S90: Please refer to Figure 2 , use the second transformation matrix to transform the coordinates of the marker M in the verification point set N6, and determine whether the transformation error is within a preset range. If so, use the second transformation matrix to perform coordinate alignment between the first medical device 10 and the second medical device 20; if not, repeat step two S20 to step eight S80 until the transformation error is within a preset range.

[0094] Further, the calculation process of the conversion error is as follows: first, the coordinate points in the verification point set N6 are converted using the second conversion matrix to obtain the converted coordinate points. Then, the coordinate points in the target point set N1 closest to the converted coordinate points are obtained as the corresponding matching points. Finally, the distance between the converted coordinate points and the corresponding matching points is calculated as the conversion error.

[0095] It can be understood that the step eight S80 and the step nine S90 are verifications of the conversion effect of the second conversion matrix. When the conversion error meets the preset range, the second conversion matrix can be used as the conversion matrix for the coordinate registration between the first medical device 10 and the second medical device 20. When the conversion error does not meet the preset range, it means that the conversion error is large and the second conversion matrix needs to be trained for convergence. Therefore, the step two S20 to the step eight S80 are re-executed to obtain a new second conversion matrix, and then judged until the second conversion matrix meets the conversion error requirements.

[0096] Preferably, in the process of repeatedly executing the step 2 S20, the coordinates of each of the markers M in the registration point set N2 acquired by the second medical device 20 are different.

[0097] Furthermore, when the second medical device 20 is an infrared laser positioning device, after step nine S90, the registration method further includes: using a target to convert the coordinate system of the surgical robot 30 into the coordinate system of the infrared laser positioning device, so as to achieve coordinate registration between the surgical robot 30 and the first medical device 10. In this embodiment, the device for coordinate system registration with the infrared laser positioning device is not limited to the surgical robot 30, but may also be other medical devices.

[0098] Based on the same inventive concept, this embodiment also provides a registration device for executing the above registration method. Figures 2 to 10 , the registration device includes: a data storage module 100, a coordinate matching module 200, a coordinate registration module 300 and a registration verification module 400. The data storage module 100 is used to store the coordinates of each marker M acquired by the first medical device 10 to form a target point set N1; the coordinates of some of the markers M acquired by the second medical device 20 to form a registration point set N2; and the coordinates of the remaining markers M acquired by the second medical device 20 to form a verification point set N6. In addition, the data storage module 100 is also used to store process data generated during the operation of the registration device.

[0099] The coordinate matching module 200 is used to select at least three coordinate points of the marker M in the registration point set N2 to form a source polygon; the coordinate points of each marker M in the target point set N1 are used to form multiple target polygons; traverse and compare the side lengths of each target polygon with the source polygon, and obtain the target polygon that meets the side length difference range to form a target polygon set N3; and, based on the source polygon and the target polygon set N3, obtain a first transformation matrix.

[0100] The coordinate registration module 300 is used to determine the point pair relationship between the coordinates of the marker M in the registration point set N2 and the coordinates of the marker M in the target point set N1 at least based on the first transformation matrix, and form a point pair set N5; and, based on the point pair set N5, obtain a second transformation matrix.

[0101] The registration verification module 400 is used to use the second transformation matrix to transform the coordinates of the marker M in the verification point set N6, and determine whether the conversion error is within a preset range. If so, the second transformation matrix is ​​used to perform coordinate registration between the first medical device 10 and the second medical device 20; if not, the data storage module 100, the coordinate matching module 200 and the coordinate registration module 300 are repeatedly operated in sequence until the conversion error is within a preset range.

[0102] In summary, the registration method and device provided in this embodiment is to select a source polygon from the registration point set N2 obtained by the second medical device 20, and obtain the target polygon in the target point set N1 corresponding to the source polygon according to the preset side length difference range, so as to realize the matching relationship between the source polygon and the coordinate points in the target point set N1, and obtain the first transformation matrix accordingly, so as to realize the initial transformation between the coordinate system of the registration point set N2 and the target point set N1. In order to improve the registration accuracy, this embodiment determines the matching relationship between each coordinate point in the registration point set N2 and the target point set N1 under the premise of the first transformation matrix, and then forms the point pair set N5, so as to obtain the second transformation matrix. In addition, this embodiment also uses the verification point set N6 to verify the matching accuracy of the second transformation matrix, and after repeated screening, converges the conversion error within the preset range, thereby obtaining the second transformation matrix with better accuracy, and realizing the automatic registration of coordinates between the first medical device 10 and the second medical device 20. Therefore, the registration method and device provided in this embodiment do not need to register the markers M one by one in sequence, thereby achieving automated and efficient registration between medical devices with high registration accuracy.

[0103] In addition, it should be recognized that although the present invention has been disclosed as a preferred embodiment, the above embodiment is not intended to limit the present invention. For any technician familiar with the art, without departing from the scope of the technical solution of the present invention, the technical content disclosed above can be used to make many possible changes and modifications to the technical solution of the present invention, or modified into equivalent embodiments of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still belongs to the scope of protection of the technical solution of the present invention.

Claims

1. A registration method for coordinate registration between medical devices, characterized in that: include: Step 1: Install multiple markers at corresponding target locations at intervals; Step 2: using the first medical device to obtain the coordinates of each of the markers to form a target point set; Using a second medical device to obtain coordinates of some of the markers to form a set of registration points; Step 3: Select at least three coordinate points of the marker from the registration point set to form a source polygon; and, forming a plurality of target polygons with the coordinate points of each of the markers in the target point set; Step 4: traverse and compare the side lengths of each of the target polygons and the source polygons, and obtain the target polygons that meet the side length difference range to form a target polygon set; Step 5: Obtain a first transformation matrix according to the source polygon and the target polygon set; Step six: determining the point pair relationship between the coordinates of the marker in the registration point set and the coordinates of the marker in the target point set at least according to the first transformation matrix, and forming a point pair set; Step 7: Obtain a second transformation matrix according to the point pair set; Step 8: using the second medical device to obtain the coordinates of the remaining markers to form a verification point set; Step nine: using the second transformation matrix to transform the coordinates of the marker in the verification point set, and determining whether the transformation error is within a preset range, and if so, using the second transformation matrix to perform coordinate registration between the first medical device and the second medical device; If not, repeat step 2 to step 8 until the conversion error is within a preset range.

2. The registration method according to claim 1, characterized in that: The source polygon and each of the target polygons have the same number of vertices.

3. The registration method according to claim 1, characterized in that: In the step three, three coordinate points of the markers are selected from the registration point set to form a source triangle; and the coordinate points of all the markers in the target point set are arranged into a plurality of target triangles.

4. The registration method according to claim 3, characterized in that: In the step 4 and the step 5, the side lengths of the target triangles and the source triangles are compared and the target triangles that meet the side length difference range are obtained to form the target polygon set; And, obtaining the first transformation matrix according to the source triangle and the target polygon set.

5. The registration method according to claim 1, characterized in that: In the step six, the coordinates of each vertex of the source polygon in the registration point set are removed, and the coordinates of the remaining markers in the registration point set are transformed using the first transformation matrix to form a transformation point set; The coordinate points in the target point set that belong to the target polygon set are removed, and the distance between each coordinate point in the conversion point set and each remaining coordinate point in the target point set is obtained, and the coordinate point in the target point set with the smallest distance is used as the pairing point of the corresponding coordinate point in the conversion point set; According to the pairing points of each coordinate point in the conversion point set, the source polygon and the target polygon set, the point pair relationship between the coordinates of the marker in the registration point set and the coordinates of the marker in the target point set is determined, and the point pair set is formed.

6. The registration method according to claim 1, characterized in that: In step one, the number of the markers is greater than or equal to 4, and any three of the markers are not collinear, and any four of the markers are not coplanar.

7. The registration method according to claim 1, characterized in that: In the step 2, the number of coordinates of the markers acquired by the second medical device is greater than or equal to 3, and any three acquired markers are not collinear.

8. The registration method according to claim 1, characterized in that: The first medical device includes a computer tomography device or a magnetic resonance device; the second medical device includes a surgical robot or an infrared laser positioning device.

9. The registration method according to claim 1, characterized in that: The second medical device is an infrared laser positioning device, and after step nine, the registration method further includes: The target is used to convert the coordinate system of the surgical robot into the coordinate system of the infrared laser positioning device, so as to align the coordinates between the surgical robot and the first medical device.

10. A registration device, characterized in that: include: a data storage module, used to store at least the coordinates of each marker acquired by the first medical device to form a target point set; The coordinates of some of the markers acquired by the second medical device to form a set of registration points; and, the coordinates of the remaining markers acquired by the second medical device to form a verification point set; A coordinate matching module, used for selecting at least three coordinate points of the markers in the registration point set to form a source polygon; and forming a plurality of target polygons with the coordinate points of each marker in the target point set; Traversing and comparing the side lengths of each of the target polygons and the source polygons, and acquiring the target polygons that meet the side length difference range to form a target polygon set; And, obtaining a first transformation matrix according to the source polygon and the target polygon set; A coordinate registration module, configured to determine, at least according to the first transformation matrix, a point pair relationship between the coordinates of the marker in the registration point set and the coordinates of the marker in the target point set, and form a point pair set; And, obtaining a second transformation matrix according to the point pair set; a registration verification module, configured to transform the coordinates of the markers in the verification point set using the second transformation matrix, and determine whether a transformation error is within a preset range, and if so, perform coordinate registration between the first medical device and the second medical device using the second transformation matrix; If not, the data storage module, the coordinate matching module and the coordinate registration module are repeatedly operated in sequence until the conversion error is within a preset range.

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