Spine vertebral pedicle isthmus rapid identification and positioning method and vertebral stent implantation path planning method

Abstract

The invention discloses a spine vertebral pedicle isthmus rapid identification and positioning method and a vertebral stent implantation path planning method, and the method comprises the steps: S1, obtaining a three-dimensional image containing a spine, and segmenting the three-dimensional image to obtain a three-dimensional image of each vertebral section; s2, searching the axial direction and the center of a vertebral hole in the three-dimensional image of the vertebral section obtained in the S1; s3, according to the axial direction of the vertebral hole and the center of the vertebral hole obtained in the S2, the spinous process direction of the vertebral section is obtained; s4, according to the spinous process direction obtained in the S3, an approximate symmetry plane of the vertebral body is constructed, and then a set number of vertebral pedicle segmentation sections perpendicular to the approximate symmetry plane are obtained; and S5, detecting two contours in each vertebral pedicle segmentation section obtained in the step S4 by adopting a boundary detection algorithm, wherein the vertebral pedicle segmentation section corresponding to the minimum area sum of the two contours is the isthmus position of the vertebral pedicle. The vertebral pedicle isthmus can be automatically identified, the identification result is rapid and accurate, the accuracy of vertebral stent implantation can be effectively improved, and the operation difficulty is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of image processing, and in particular to a method for quickly identifying and locating a spinal pedicle isthmus and a method for planning a vertebral stent placement path. Background Art

[0002] Percutaneous kyphoplasty (PKP), as a type of minimally invasive surgery, has been widely used in the treatment of vertebral compression fractures. By placing a bone expander or vertebral stent into the compressed part of the patient's vertebra, expanding it to restore its height, and injecting bone cement under low pressure to further stabilize the vertebra, it can effectively relieve the patient's pain and prevent further compression and collapse of the vertebra.

[0003] Among them, the square cone stent has a flat rectangular structure at the end of the main body. It is widely used because it can effectively open the compressed vertebral body in a directional manner and provide better stability and support. During the operation, the square expander needs to be inserted from the long pedicle isthmus (PI, which refers to the narrow part of the vertebral arch between the upper and lower articular processes) of the cone. The entire placement process has high technical requirements. The structure of the pedicle isthmus is complex. In order to ensure that the vertebral stent accurately reaches the vertebral compression part, the doctor must have rich anatomical knowledge and clinical experience to judge and adjust the insertion angle. The operation is complicated and the accuracy is not high. The surgical effect is not good and it is easy to increase the surgical risk. Therefore, a method for automatically and accurately identifying the pedicle isthmus of the cone with the assistance of a surgical robot is proposed, which is of great significance for improving the accuracy of vertebral stent placement and reducing the difficulty of surgery. Summary of the invention

[0004] Purpose of the invention: In view of the above-mentioned deficiencies, the present invention proposes a method for quickly identifying and locating the isthmus of the pedicle of the spine and a method for planning the path for the placement of a vertebral stent, which can automatically identify the isthmus of the pedicle of the spine, and the recognition result is fast and accurate, which can effectively improve the accuracy of the placement of the vertebral stent and reduce the difficulty of the operation.

[0005] Technical solution:

[0006] The present invention provides a method for quickly identifying and locating a spinal pedicle isthmus, comprising the steps of:

[0007] S1, obtaining a three-dimensional image of the spine, and segmenting the three-dimensional image of each vertebra therein;

[0008] S2, finding the axis direction and center of the vertebral foramen in the three-dimensional image of the vertebra obtained in S1;

[0009] S3, obtaining the spinous process direction of the vertebral segment according to the axial direction and center of the vertebral foramen obtained in S2;

[0010] S4, constructing an approximate symmetry plane of the vertebral body according to the spinous process direction obtained in S3, and then obtaining a set number of pedicle segmentation sections perpendicular to the approximate symmetry plane;

[0011] S5. Using a boundary detection algorithm to detect the two contours in each pedicle segmentation section obtained in S4, the pedicle segmentation section corresponding to the minimum sum of the areas of the two contours is the pedicle isthmus position.

[0012] Specifically, the S2 includes:

[0013] S21, using the front-to-back direction and the left-to-right direction of the human body as rotation axes, respectively, the three-dimensional image of the vertebral segment is rotated at a set angle step length, and after each rotation, parallel light projection is performed along the head-to-foot direction of the human body to obtain two sets of projection images;

[0014] S22, obtaining the closed areas in the two groups of projection images obtained in S21, and calculating their areas. For each group of projection images, obtaining the projection image corresponding to the largest area and its rotation angle, and calculating the axis direction and center of the vertebral foramen based on the above.

[0015] More specifically, in S22, when the projection direction is in the same direction as the axial direction of the vertebral foramen, the area of ​​the vertebral foramen region in the projection image reaches a maximum, that is, there is a projection image in both the two groups of projection images, whose vertebral foramen region area reaches a maximum, thereby calculating the axial direction of the vertebral foramen in the three-dimensional image of the vertebral segment, and at the same time, according to the center point of the vertebral foramen region in each of the two groups of projection images, whose vertebral foramen region area reaches a maximum, the vertebral foramen center of the vertebral segment is calculated.

[0016] Specifically, S3 includes:

[0017] S31, calculating the center of mass of all voxels in the vertebral segment, rotating the line connecting the center of the vertebral foramen obtained in S2 and the center of mass around the axis of the vertebral foramen by a set angle, and extracting an image containing the spinous process based on the rotation angle;

[0018] S32. With the vertebral foramen center as the center, between the two extreme positions of the line connecting the vertebral foramen center and the center of mass, a straight line passing through the vertebral foramen center is created at every set rotation angle. The straight line intersects with the spinous process boundary to obtain a boundary point, and the direction of the straight line corresponding to the maximum distance between the boundary point and the vertebral foramen center is obtained, which is the direction of the spinous process.

[0019] More specifically, in S31, the line connecting the center of the vertebral foramen obtained in S2 and the center of mass is rotated around the axis of the vertebral foramen by a set angle of [-γ, γ], and the structure located above the center of the vertebral foramen between the two extreme positions of the line connecting the center of the vertebral foramen and the center of mass is the extracted image containing the spinous process.

[0020] Specifically, in S4, a set number of pedicle segmentation sections perpendicular to the approximate symmetry plane are obtained, specifically:

[0021] A pedicle segmentation plane passing through the center of the vertebral foramen and perpendicular to the approximate symmetric plane of the vertebral body is constructed, and the pedicle segmentation plane is moved along the spinous process by a set distance D to obtain an upper pedicle segmentation plane and a lower pedicle segmentation plane. Between the upper pedicle segmentation plane and the lower pedicle segmentation plane, a number of pedicle segmentation sections are obtained at every set distance step.

[0022] More specifically, the set distance D is 20 mm.

[0023] More specifically, the set distance step may be 0.3-0.8 mm.

[0024] The present invention also provides a vertebral stent placement path planning method, comprising the steps of:

[0025] (1) Using the aforementioned spinal pedicle isthmus rapid identification and positioning method to locate the position of the pedicle isthmus;

[0026] (2) Obtain the maximum inscribed shape corresponding to the position of the pedicle isthmus located in step (1) and the shape of the vertebral stent, and use the center of the maximum inscribed shape as the axial direction of the vertebral stent insertion. The cross-section of the vertebral stent is consistent with the maximum inscribed shape, thereby planning the vertebral stent insertion path.

[0027] Specifically, the vertebral stent is a square spreader, the maximum inscribed shape is a maximum inscribed rectangle, the center of the maximum inscribed rectangle is used as the axial direction of the square spreader, and the end face of the square spreader is parallel to the long axis direction of the maximum inscribed rectangle, thereby planning the vertebral stent insertion path.

[0028] Beneficial effects: The present invention obtains the direction of the spinous process of the vertebra, constructs an approximate symmetry plane of the vertebra, and then obtains the pedicle segmentation section. By detecting the area of ​​two contours and the smallest corresponding pedicle segmentation section, the position of the pedicle isthmus can be quickly and accurately obtained; through image processing and analysis, the accuracy of vertebral stent placement is effectively improved, human errors are reduced, and the surgical efficiency is improved while reducing the difficulty of the operation, which is of great significance to the accuracy and safety of pedicle screw placement surgery; the present invention can automatically identify the pedicle isthmus. The pedicle isthmus is an important anatomical feature of the vertebra, and the accurate identification of its position geometry information plays an important role in promoting the more automated and intelligent development of robot-assisted orthopedic surgery (pedicle screws, percutaneous nails, reduction and fusion internal fixation surgery, etc.). BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are merely embodiments of the present invention, and ordinary technicians in this field can obtain other drawings based on these drawings without creative work.

[0030] Figure 1 It is a flow chart of the method for quickly identifying and locating the spinal pedicle isthmus of the present invention;

[0031] Figure 2 is an example of a three-dimensional image of a vertebral segment, where: Figure 2 (a) is an example of a vertebral surface drawing image. Figure 2 (b) is an example of a volume rendering image of a vertebral segment;

[0032] Figure 3 A schematic diagram for finding the axial direction of the vertebral foramen in a three-dimensional image of a vertebral segment, wherein: Figure 3 (a) is a schematic diagram of rotating the three-dimensional image of the vertebral segment with the front-back direction of the human body as the rotation axis. Figure 3 (b) is a schematic diagram of rotating the three-dimensional image of the vertebral segment with the left-right direction of the human body as the rotation axis;

[0033] Figure 4 for Figure 3 Example diagrams of projection images obtained at different rotation angles, wherein the upper diagram is an example diagram of a projection image obtained by rotating the three-dimensional image of the vertebral segment with the front-to-back direction of the human body as the rotation axis, and the lower diagram is an example diagram of a projection image obtained by rotating the three-dimensional image of the vertebral segment with the left-to-right direction of the human body as the rotation axis;

[0034] Figure 5 is a schematic diagram of the extracted spinous process, where Figure 5 (a) is an example diagram of the line between the center of the vertebral foramen and the centroid of the vertebral segment. Figure 5 (b) is a schematic diagram of the extracted spines;

[0035] Figure 6 A schematic diagram for obtaining the direction of the spinous process of the vertebra;

[0036] Figure 7 To obtain a schematic diagram of the pedicle segmentation section, Figure 7 (a) is a schematic diagram of constructing the upper and lower pedicle segmentation planes. Figure 7 (b) is a schematic diagram of the obtained pedicle segmentation section;

[0037] Figure 8 Schematic diagram of the path planning for the insertion of the square spreader. DETAILED DESCRIPTION

[0038] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0039] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present invention should have the common meanings understood by persons having ordinary skills in the field to which the present invention belongs.

[0040] The process of the method for quickly identifying and locating the spinal pedicle isthmus of the present invention is as follows: Figure 1 As shown, including:

[0041] S1, obtaining a three-dimensional image of the spine, and segmenting the three-dimensional image of each vertebra therein;

[0042] Reference Figure 2 The three-dimensional image of the vertebra contains all the voxel information and triangular patch information of a single vertebra, such as Figure 2 (a) is a surface rendering image of a vertebral segment, indicating the surface information of the segmented vertebral segment; Figure 2 (b) is a volume rendering image of the vertebral segment, indicating Figure 2 Voxel information of the segmented vertebrae in (a).

[0043] S2, finding the axis direction and center of the vertebral foramen in the three-dimensional image of the vertebra obtained in S1;

[0044] Due to the structural characteristics of the vertebral body, the axial direction of the vertebral foramen is usually approximately perpendicular to the anterior and posterior end surfaces of the vertebral body.

[0045] In the present invention, the axial direction of the vertebral foramen in the three-dimensional image of the vertebral segment is found as follows:

[0046] S21, taking the human body cross section as a reference, taking the front-back direction and the left-right direction of the human body as rotation axes, respectively, rotating the three-dimensional image of the vertebral segment at a set angle step, and performing parallel light projection along the head-foot direction of the human body after each rotation, to obtain two sets of projection images;

[0047] A cross-section of the human body is a plane parallel to the ground that divides the human body into upper and lower parts. In medical imaging, a cross-sectional image is a view from above, such as the image presented in a CT or MRI scan, which helps to show the layers of the internal structure of the human body. Figure 3 , taking the human body cross section as the reference, taking the Z axis and X axis of the image coordinate system as the rotation axis, setting the angle step to rotate, and after each rotation, parallel light projection is performed along the Y axis direction of the image coordinate system to obtain the projection image; Figure 3 (a) Taking the cross section of the human body as the reference and the Z axis of the image coordinate system as the rotation axis, the rotation angle during parallel projection is defined as θ i ,θ iThe value range of is 0°-180°, and the resulting projection image is as follows Figure 4 As shown in the figure above, the closed area in the projection image is the vertebral foramen area, denoted as S i ;like Figure 3 (b) Taking the cross section of the human body as the reference and the X-axis of the image coordinate system as the rotation axis, the rotation angle during parallel projection is defined as α j , α j The value range of is 0°-180°, and the resulting projection image is as follows Figure 4 As shown in the figure below, the vertebral foramen area is denoted as S j .

[0048] S22, obtaining the closed areas in the two groups of projection images obtained in S21, and calculating their areas, and for each group of projection images, obtaining the projection image corresponding to the largest area and its rotation angle, and calculating the axis direction and center of the vertebral foramen based on the above;

[0049] When the projection direction is in the same direction as the axis direction of the vertebral foramen, the area of ​​the vertebral foramen in the projection image reaches the maximum, that is, there is a projection image in both sets of projection images, and its vertebral foramen area S i and S j The area reaches the maximum, so that the angle θ of rotation with the Z axis and X axis of the image coordinate system as the rotation axis can be obtained. i and α j , thus the axial direction of the vertebral foramen in the three-dimensional image of the vertebral segment can be calculated. At this time, according to the center point of the vertebral foramen area in the projection image where the area of ​​each vertebral foramen in the two groups of projection images reaches the maximum, the vertebral foramen center P of the vertebral segment in the three-dimensional image can be calculated. z .

[0050] The two rotation axes are rotated at a set angle step size, and the projection image areas at different rotation angles are compared. The two projection images with the largest areas jointly determine the center point of the same vertebral foramen area, ensuring the recognition accuracy of the vertebral foramen center position.

[0051] S3, obtaining the spinous process direction of the vertebral segment according to the axial direction and center of the vertebral foramen obtained in S2;

[0052] S31, calculating the center of mass of all voxels in the vertebral segment, rotating the line connecting the center of the vertebral foramen obtained in S2 and the center of mass around the axis of the vertebral foramen by a set angle, and extracting an image containing the spinous process based on this;

[0053] Reference Figure 5, the front and rear end surfaces of the vertebral segment are obtained according to the axial direction of the vertebral foramen obtained by S2, and the center of mass of all voxels in the vertebral segment is calculated as P. Because the vertebral body occupies most of the voxels of the entire vertebral segment and is approximately bilaterally symmetrical, the center of mass P of all voxels in the vertebral segment is basically located approximately directly below the center of the vertebral foramen, such as Figure 5 (a) shows the center of the vertebral foramen P z The line between the center of mass P is L. From the perspective of the anterior or posterior end of the vertebral segment, the line L is rotated around the axis of the vertebral foramen by a set angle. The set angle is defined as [-γ, γ]. In the present invention, γ can be 10°. Then the two extreme positions of the line L are located at the center of the vertebral foramen P. z The structure above is the extracted image containing the spinous process, such as Figure 5 (b) as shown.

[0054] S32, acquiring the direction of the spinous process according to the image containing the spinous process extracted in S31;

[0055] Reference Figure 6 According to the image containing the spinous process extracted by S31, with the center of the vertebral foramen as the center, between the two extreme positions of the line connecting the center of the vertebral foramen and the center of mass, a straight line L passing through the center of the vertebral foramen is created at every set rotation angle. k The straight line intersects with the spinous process boundary to obtain a boundary point P k , get the boundary point P k The direction of the straight line corresponding to the maximum distance from the center of the vertebral foramen is the direction of the spinous process.

[0056] S4, constructing an approximate symmetry plane of the vertebral body according to the spinous process direction obtained in S3, and then obtaining a set number of pedicle segmentation sections, where the pedicle segmentation sections are perpendicular to the approximate symmetry plane;

[0057] The approximate symmetry plane of the constructed vertebra is a plane parallel to the spinous process and perpendicular to the anterior and posterior end surfaces of the vertebra.

[0058] Reference Figure 7 (a) The spinous process direction obtained by S3 is the straight line L in the figure. z , vertebral foramen center P Z and the axial direction of the vertebral foramen, an approximate symmetric plane of the vertebral body can be constructed, and the approximate symmetric plane can divide the vertebral body into two approximately symmetrical parts. Then the pedicle segmentation plane M is constructed, and the pedicle segmentation plane M passes through the center of the vertebral foramen P Z , and perpendicular to the approximate symmetric plane of the vertebral body, the pedicle segmentation plane M is moved along the spinous process by a set distance D to obtain the pedicle upper segmentation plane M top and the lower pedicle segmentation surface M bot ,like Figure 7 As shown in (a), the segmentation surface M on the pedicle top and the lower pedicle segmentation surface Mbot At every set distance step, several pedicle segmentation sections are obtained, such as Figure 7 (b) as shown.

[0059] In the present invention, the set distance D can be 20 mm. The average height of the human pedicle is about 12-20 mm. The pedicle segmentation surface M moves 20 mm along the spinous process direction, which can ensure that the pedicle segmentation surface M top and the lower pedicle segmentation surface M bot The actual pedicle area can be included in between.

[0060] In the present invention, the set distance step may be 0.3-0.8 mm, and in this embodiment, 0.5 mm is preferred.

[0061] In step S3, the spinous process area is accurately located and the spinous process direction is determined, so that the vertebral symmetry plane can be constructed. By constructing an approximate symmetry plane, the structure of the vertebral body is simplified, and it is also convenient to establish multiple upper and lower pedicle segmentation planes, helping to quickly and accurately segment the actual pedicle area.

[0062] S5, using a boundary detection algorithm to detect two contours in each pedicle segmentation section obtained in S4, wherein the pedicle segmentation section corresponding to the minimum sum of the areas of the two contours is the position of the pedicle isthmus;

[0063] The pedicle segmentation plane intercepts the pedicle and generates two approximately elliptical images on the left and right. The two approximately elliptical areas correspond to the left and right parts of the pedicle respectively. The conventional boundary detection algorithm such as Canny edge can detect the two contours E l and E r The pedicle isthmus (PI) is the smallest part of the pedicle cross section. l and E r When the sum of the enclosed areas is the smallest, the corresponding intercepted part is the pedicle isthmus, and the location of the pedicle isthmus can be found based on this.

[0064] The present invention also provides a vertebral stent placement path planning method, comprising the steps of:

[0065] (1) Using the aforementioned spinal pedicle isthmus rapid identification and positioning method to locate the position of the pedicle isthmus;

[0066] (2) Obtain the maximum inscribed shape corresponding to the position of the pedicle isthmus located in step (1) and the shape of the vertebral stent, and use the center of the maximum inscribed shape as the axial direction of the vertebral stent insertion. The cross section of the vertebral stent is consistent with the maximum inscribed shape, thereby planning the vertebral stent insertion path. In the present invention, the vertebral stent is a square spacer, so the maximum inscribed shape is the maximum inscribed rectangle, such as Figure 8As shown, the center P of the maximum inscribed rectangle el , P er As the axial direction of the square spreader, the end surface of the square spreader and the major axis direction L of the maximum inscribed rectangle el , L er The vertebral stent placement path is planned accordingly.

[0067] The present invention obtains the spinous process direction of the vertebral segment, constructs an approximate symmetry plane of the vertebral body, and then obtains the pedicle segmentation section. By detecting the area of ​​two contours and the minimum corresponding pedicle segmentation section, the position of the pedicle isthmus can be quickly and accurately obtained; through image processing and analysis, the accuracy of vertebral stent placement is effectively improved, human errors are reduced, and the surgical efficiency is improved while reducing the difficulty of the operation, which is of great significance to the accuracy and safety of pedicle screw placement surgery; the present invention can automatically identify the pedicle isthmus. The pedicle isthmus is an important anatomical feature of the vertebral segment. The accurate identification of its position geometry information has an important role in promoting the more automated and intelligent development of robot-assisted orthopedic surgery (pedicle screws, percutaneous nails, reduction fusion internal fixation surgery, etc.).

[0068] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0069] The embodiments of the present invention are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for quickly identifying and locating the isthmus of a pedicle of a spine, characterized in that: Includes steps: S1, obtaining a three-dimensional image of the spine, and segmenting the three-dimensional image of each vertebra therein; S2, finding the axis direction and center of the vertebral foramen in the three-dimensional image of the vertebra obtained in S1; S3, obtaining the spinous process direction of the vertebral segment according to the axial direction and center of the vertebral foramen obtained in S2; S4, constructing an approximate symmetry plane of the vertebral body according to the spinous process direction obtained in S3, and then obtaining a set number of pedicle segmentation sections perpendicular to the approximate symmetry plane; S5. Using a boundary detection algorithm to detect the two contours in each pedicle segmentation section obtained in S4, the pedicle segmentation section corresponding to the minimum sum of the areas of the two contours is the pedicle isthmus position.

2. The method for rapid identification and positioning of the spinal pedicle isthmus according to claim 1, characterized in that: The S2 includes: S21, using the front-to-back direction and the left-to-right direction of the human body as rotation axes, respectively, the three-dimensional image of the vertebral segment is rotated at a set angle step length, and after each rotation, parallel light projection is performed along the head-to-foot direction of the human body to obtain two sets of projection images; S22, obtaining the closed areas in the two groups of projection images obtained in S21, and calculating their areas. For each group of projection images, obtaining the projection image corresponding to the largest area and its rotation angle, and calculating the axis direction and center of the vertebral foramen based on the above.

3. The method for rapid identification and positioning of the spinal pedicle isthmus according to claim 2, characterized in that: In S22, when the projection direction is in the same direction as the axial direction of the vertebral foramen, the area of ​​the vertebral foramen region in the projection image reaches a maximum, that is, there is a projection image in both the two groups of projection images, and the area of ​​the vertebral foramen region reaches a maximum, thereby calculating the axial direction of the vertebral foramen in the three-dimensional image of the vertebral segment, and at the same time, according to the center point of the vertebral foramen region in each of the projection images in which the area of ​​the vertebral foramen region reaches a maximum, the vertebral foramen center of the vertebral segment is calculated.

4. The method for rapid identification and positioning of the spinal pedicle isthmus according to claim 1, characterized in that: The S3 includes: S31, calculating the center of mass of all voxels in the vertebral segment, rotating the line connecting the center of the vertebral foramen obtained in S2 and the center of mass around the axis of the vertebral foramen by a set angle, and extracting an image containing the spinous process based on the rotation angle; S32. With the vertebral foramen center as the center, between the two extreme positions of the line connecting the vertebral foramen center and the center of mass, a straight line passing through the vertebral foramen center is created at every set rotation angle. The straight line intersects with the spinous process boundary to obtain a boundary point, and the direction of the straight line corresponding to the maximum distance between the boundary point and the vertebral foramen center is obtained, which is the direction of the spinous process.

5. The method for rapid identification and positioning of the spinal pedicle isthmus according to claim 4, characterized in that: In S31, the line connecting the center of the vertebral foramen and the center of mass obtained in S2 is rotated around the axis of the vertebral foramen by a set angle of [-γ, γ], and the structure located above the center of the vertebral foramen between the two extreme positions of the line connecting the center of the vertebral foramen and the center of mass is the extracted image containing the spinous process.

6. The method for rapid identification and positioning of the spinal pedicle isthmus according to claim 1, characterized in that: In S4, a set number of pedicle segmentation sections perpendicular to the approximate symmetry plane are obtained, specifically: A pedicle segmentation plane passing through the center of the vertebral foramen and perpendicular to the approximate symmetric plane of the vertebral body is constructed, and the pedicle segmentation plane is moved along the spinous process by a set distance D to obtain an upper pedicle segmentation plane and a lower pedicle segmentation plane. Between the upper pedicle segmentation plane and the lower pedicle segmentation plane, a number of pedicle segmentation sections are obtained at every set distance step.

7. The method for rapid identification and positioning of the spinal pedicle isthmus according to claim 6, characterized in that: The set distance D is 20 mm.

8. The method for rapid identification and positioning of the spinal pedicle isthmus according to claim 6, characterized in that: The set distance step may be 0.3-0.8 mm.

9. A vertebral stent placement path planning method, characterized in that: Includes steps: (1) using the method for rapid identification and positioning of the spinal pedicle isthmus according to any one of claims 1 to 8 to locate the position of the pedicle isthmus; (2) Obtain the maximum inscribed shape corresponding to the position of the pedicle isthmus located in step (1) and the shape of the vertebral stent, and use the center of the maximum inscribed shape as the axial direction of the vertebral stent insertion. The cross-section of the vertebral stent is consistent with the maximum inscribed shape, thereby planning the vertebral stent insertion path.

10. The vertebral stent placement path planning method according to claim 9, characterized in that: The vertebral stent is a square spreader, the maximum inscribed shape is a maximum inscribed rectangle, the center of the maximum inscribed rectangle is used as the axial direction of the square spreader, and the end face of the square spreader is parallel to the long axis direction of the maximum inscribed rectangle, thereby planning the vertebral stent insertion path.

Images