Puncture needle spatial pose unification method and system

Abstract

The application discloses a puncture needle space pose unification method and system, and the method comprises the following steps: acquiring first position information of a mark point of a puncture object in a first coordinate system; acquiring second position information of the mark point in a second coordinate system by operating a puncture needle; obtaining a position transfer matrix according to the first position information and the second position information; unifying the position of the puncture needle based on the position transfer matrix; acquiring second direction information of the puncture needle in the second coordinate system; and obtaining pose information of the puncture needle in the first coordinate system according to the second direction information and the position transfer matrix. The application can improve the accuracy of puncture needle pose unification.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of engineering, in particular to a puncture needle space pose unification method and system. BACKGROUND

[0002] Liver cancer is the first killer of cancer in China and the world. Currently, CT-guided liver puncture, biopsy surgery, etc. as an important diagnostic method. Puncture surgery refers to the puncture needle into the body cavity, extract the liquid for further testing or inject certain chemicals or air into the body cavity, as a kind of treatment or examination method and widely used in clinical. According to the different conditions, different parts of the puncture operation can be performed. Commonly used in clinical practice include epidural puncture, thoracentesis, peritoneocentesis, lumbar puncture, arterial and venous puncture, etc. Puncture needle belongs to interventional radiology equipment, which is one of the necessary consumables for puncture surgery. The operation currently mainly relies on the doctor to operate the needle manually, and then the medical image is confirmed. The operation has low precision and high risk, which leads to long operation time and easy to cause complications. In order to solve the above problems, the operation assisted by the surgical robot is gradually popular in recent years, and the research on the needle assisted by the robot has also been for a certain time. The use of robot-assisted surgery involves problems such as puncture needle space registration between puncture instruments, CT medical imaging equipment, mechanical arm and other peripherals, and puncture precision. At present, a part of the operation in the market is completed by the surgical robot in cooperation with the doctor, the surgical robot plans the puncture path and angle, and the doctor only needs to complete the needle insertion action according to the angle. However, there is still a certain error, and if the recommended path and angle are not suitable, the doctor needs to manually modify the needle insertion path according to experience and medical knowledge to predict the tumor position and needle insertion angle. SUMMARY

[0003] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application provides a puncture needle space pose unification method and system, which can improve the accuracy of puncture needle pose unification.

[0004] One aspect of the embodiment of the present application provides a puncture needle space pose unification method, comprising the following steps: obtaining first position information of a landmark point of a puncture object in a first coordinate system; positioning the landmark point in a second coordinate system by operating a puncture needle; obtaining a position transfer matrix according to the first position information and the second position information; performing position unification on the puncture needle based on the position transfer matrix; obtaining second direction information of the puncture needle in the second coordinate system; and obtaining attitude information of the puncture needle in the first coordinate system according to the second direction information and the position transfer matrix.

[0005] According to some embodiments of the present application, the acquiring the position information of the landmark points of the puncture object in the first coordinate system comprises: acquiring original data containing information of the landmark points by CT imaging; and segmenting the landmark points by a medical image segmentation algorithm to acquire the position information of each landmark point in the first coordinate system.

[0006] According to some embodiments of the present application, the positioning the second position information of the landmark points in the second coordinate system by operating the puncture needle comprises: operating the needle tip point of the puncture needle at the center of each landmark point; positioning and tracking a plurality of passive beads arranged on the puncture needle by an optical device to obtain the position information of the passive beads in the second coordinate system; and obtaining the second position information of the landmark points in the second coordinate system according to the position information and the structure of the puncture needle.

[0007] According to some embodiments of the present application, the structure of the puncture needle is a Y-shaped structure comprising a pen body and a split needle tip; the plurality of passive beads comprises a first passive bead, a second passive bead, a third passive bead and a fourth passive bead; and the method further comprises: establishing a rectangular coordinate system with the needle tip of the puncture needle as the origin and the pen body as the X axis to obtain a third coordinate system; and wherein the first passive bead and the second passive bead are located on the X axis.

[0008] According to some embodiments of the present application, the position unification of the puncture needle based on the position transfer matrix comprises: obtaining fourth position information of the passive beads in the first coordinate system according to the third position information of the passive beads of the puncture needle in the second coordinate system and the position transfer matrix.

[0009] According to some embodiments of the present application, the acquiring the second direction information of the puncture needle in the second coordinate system comprises: obtaining the second direction information of the puncture needle in the second coordinate system according to the position information of the first passive bead and the second passive bead in the second coordinate system.

[0010] According to some embodiments of the present application, the obtaining the attitude information of the puncture needle in the first coordinate system according to the second direction information and the position transfer matrix comprises: obtaining a direction vector in the second direction information and obtaining position information of a point on the direction vector; obtaining the position information of the point in the first coordinate system according to the position transfer matrix; obtaining a straight direction vector of the puncture needle in the first coordinate system according to the position information of the point and obtaining corresponding attitude information.

[0011] According to some embodiments of the present application, the operation of the needle tip point of the puncture needle is at the center of each of the mark points; the passive small balls arranged on the puncture needle are tracked by the optical device to obtain position information of the passive small balls in the second coordinate system, including: stopping the needle tip at the center point of each of the mark points for several seconds, and obtaining the several position information at each of the center points, and averaging the position information to obtain the position information of the center point of each of the mark points.

[0012] Another aspect of the embodiment of the present application provides a puncture needle space pose unification system for implementing the puncture needle space pose unification method, including: a puncture needle including a body and a plurality of passive small balls arranged on the body; a puncture object including an object body and a plurality of mark points arranged on the body; an optical device for tracking the passive small balls; and a CT imaging module for CT imaging of the puncture object.

[0013] The embodiment of the present application has at least the following beneficial effects: the embodiment of the present application proposes a high-precision puncture needle pose real-time unification method based on an optical device, which can accurately calculate the multi-system transformation relationship between the puncture needle, the CT, the marker and the optical device, without manual intervention by the doctor. The method of matching the surgical needle and the marker by using the image before the operation is proposed, and an error feedback compensation method for accurately obtaining the workpiece position information is also proposed, which reduces the registration error to a certain extent and ensures the accuracy of the pose. The overall registration method is high in accuracy and easy to implement, and can be easily applied to engineering implementation.

[0014] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0015] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, including the appended drawings.

[0016] Figure 1 A flowchart of the method of the embodiment of the present application is shown;

[0017] Figure 2 A structure diagram of the puncture needle of the embodiment of the present application is shown;

[0018] Figure 3 A puncture needle in the NDI coordinate system of the embodiment of the present application is shown;

[0019] Figure 4 A module schematic block diagram of the system of the embodiment of the present application is shown;

[0020] Figure 5A schematic diagram of a field layout for use in embodiments of the present application.

[0021] Reference signs:

[0022] Puncture needle 100, puncture object 200, optical device 300, CT imaging module 400. DETAILED DESCRIPTION

[0023] Embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by reference to the drawings are exemplary and are for the purpose of explanation only, and are not to be understood as limiting the present application.

[0024] In the description of the present application, the meaning of one or more is one or more, the meaning of multiple is two or more, greater than, less than, more than, etc. are understood as not including the number, above, below, within, etc. are understood as including the number. If it is described that the first, the second is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the order of indicated technical features.

[0025] In order to accurately realize the pose unification of the puncture needle in different coordinate systems, including position and attitude unification, the present application proposes an engineering implementation method of real-time spatial pose unification based on self-defined markers, which combines optical and CT images to make the pose unification accuracy more accurate, and at the same time solves the problem of the current doctor's manual needle insertion and process trouble.

[0026] In order to overcome the deficiency of real-time pose unification, the present application designs a self-defined workpiece (puncture needle) as a marker, and realizes a high-precision real-time pose unification method through the attitude information of the marker in different coordinate systems. First, position unification: obtain the position information in different coordinate systems, obtain the corresponding conversion matrix according to the corresponding position information in two coordinate systems, so as to realize the unification of the positions in different coordinate systems; second, attitude unification: i.e. the rotation of the workpiece, according to the designed workpiece structure, obtain the direction information of the workpiece in the current coordinate system, obtain the direction vector of the workpiece according to the mathematical space geometry knowledge, and combine the conversion matrix generated by the position unification to realize the corresponding unification of the attitude.

[0027] Reference Figure 1The method of the embodiment of the present application comprises the following steps: acquiring first position information of a landmark point of a puncture object in a first coordinate system; acquiring second position information of the landmark point in a second coordinate system by operating a puncture needle; obtaining a position transfer matrix according to the first position information and the second position information; performing position unification on the puncture needle based on the position transfer matrix; acquiring second direction information of the puncture needle in the second coordinate system; and obtaining attitude information of the puncture needle in the first coordinate system according to the second direction information and the position transfer matrix.

[0028] The first coordinate system in the embodiment is a coordinate system under a CT imaging image, and the second coordinate system is implemented by an NDI optical device for tracking a position of the puncture needle.

[0029] The puncture needle in the embodiment of the present application is a self-defined workpiece and is implemented based on an NDI optical device. The workpiece design meets the requirements of the optical device mechanism, including a unique structure, the number of passive small balls on the structure being not less than three, and the shortest distance between the passive balls.

[0030] With reference to Figure 2 For example, the structure of the puncture needle is a Y-shaped structure, including a pen body and a split pen tip; the passive small balls include a first passive small ball, a second passive small ball, a third passive small ball, and a fourth passive small ball; and the method of the present application further comprises: establishing a rectangular coordinate system with the pen tip of the puncture needle as the origin and the pen body as the X axis to obtain a third coordinate system. The puncture needle in the embodiment meets the requirements of the workpiece structure and is convenient for practical application. In the embodiment, the basic parameter information of the workpiece is preset according to the practical requirements of the workpiece of the optical device, the pen tip is the origin position, the four small balls are on the xy plane, the first passive small ball and the second passive small ball are on the x axis, and the first passive small ball and the second passive small ball are in the negative direction of the x axis.

[0031] Since the NDI optical navigation device is used in the embodiment of the present application, the workpiece structure design is mainly designed according to the official requirements of the NDI navigation device. Not all mechanism designs can be directly used. The small balls must be designed based on the tool design requirements of the NDI. All the small balls are not on the same plane, three small balls cannot be on a straight line at the same time, the angle cannot be a right angle, and the distance between two small balls cannot be less than 45 mm. The workpiece in the embodiment of the present application is a Y-shaped structure and uses four small balls. Since the NDI official tool can acquire the position information of the user-defined center point in real time according to the position of the small ball on the workpiece, the pen tip position is set as the center point of the workpiece in some embodiments.

[0032] In hardware, the whole workpiece is made of aluminum alloy material, composed of a pen tip, a pen body, an NDI ball assembly and the like. The workpiece is provided with a battery and can work continuously for 4 hours. A switch key is arranged on the side of the pen body to realize the switching on and off of the pen. A signal acquisition confirmation and deletion key is arranged on the front face of the pen body. Through the built-in wireless wifi signal, the pointed position of the pen tip can be automatically picked up, deleted and edited. In addition, a state indicating lamp is arranged on the pen body, so that the user can confirm whether the related operation is completed according to the state indicating lamp. The ball itself is a passive identification ball produced by NDI Company. The overall structure design meets the requirements of NDI Company and is convenient for posture calculation.

[0033] In some embodiments, the method for obtaining the position information of the landmark points of the puncture object in the first coordinate system comprises: obtaining the original data containing the information of the landmark points through CT imaging; segmenting the landmark points through a medical image segmentation algorithm to obtain the position information of each landmark point in the first coordinate system.

[0034] In some embodiments, the second position information of the landmark points in the second coordinate system through the operation of the puncture needle comprises: the tip point of the puncture needle is at the center of each landmark point; the positions of the passive balls arranged on the puncture needle are tracked through the optical equipment to obtain the position information of the passive balls in the second coordinate system; and the second position information of the landmark points in the second coordinate system is obtained according to the position information and the structure of the puncture needle. In this embodiment, the tip position is the center point of the puncture needle. The official tool of NDI can obtain the position information of the user-defined center point (i.e. the tip) in real time according to the positions of the passive balls on the puncture needle, so as to obtain the second position information of the landmark points in the second coordinate system.

[0035] In some embodiments, the method for uniformly positioning the puncture needle by taking the abdominal phantom as the puncture object comprises:

[0036] Step 1: six landmark points are placed on the abdominal phantom. The original data of the phantom containing the information of the landmark points are obtained through CT imaging. Then, the landmark points are segmented through the currently popular reading software to obtain the position information P1(x, y, z) of each landmark point in the image.

[0037] Step 2: the position information of each landmark point under the optical equipment is obtained. First, the tip point of the puncture needle is at the center of each landmark point, so as to obtain the position coordinates P2(x, y, z) of each landmark point under the optical equipment.

[0038] Third step: obtain the position information of the mark points in different coordinate systems through the first two steps, and obtain the position conversion matrix T1 of the abdominal phantom. Because only the position information in two coordinate systems is considered here, rotation is not involved, the conversion matrix of the object can be obtained according to the translation of the point in three-dimensional space. That is, point P (x, y, z) is translated by a certain distance d in x, y and z directions respectively to obtain point P1 (x1, y1, z1), and the relationship between the two points is:

[0039] x1-x+d1;y1=y+d2;z1=z+d3.

[0040] Therefore, the corresponding homogeneous conversion matrix can be represented as:

[0041] ;

[0042] Here, the uniformity of the puncture needle position is mainly to unify the TP straight line of the puncture needle to the corresponding virtual human body coordinate. According to the surface of the five small balls of the phantom, the corresponding conversion matrix is obtained by using the vtk calibration function library to realize the space position unification. Here, the small ball position point information in the NDI coordinate system is the position information of the small ball in the virtual human body. The position information of each small ball is obtained by segmenting the small ball through a medical image segmentation algorithm, and then the center of gravity of each small ball is determined to determine its position information in the virtual human body. The corresponding conversion matrix is:

[0043] .

[0044] In some embodiments, the method for obtaining the second direction information of the puncture needle in the second coordinate system comprises: obtaining the second direction information of the puncture needle in the second coordinate system according to the position information of the first passive ball and the second passive ball in the second coordinate system. Since the structure design of the puncture needle in this embodiment makes the two first passive balls and the second passive ball in the direction of the needle tip simultaneously on the X axis, and the direction of the two passive balls is parallel to the direction of the needle tip, the direction information of the current posture can be obtained through the positions of the two passive balls, which is also the direction of the puncture needle.

[0045] In some embodiments, the method for obtaining the posture information of the puncture needle in the first coordinate system according to the second direction information and the position conversion matrix comprises: obtaining a direction vector in the second direction information, and obtaining the position information of a point on the direction vector; obtaining the position information of the point in the first coordinate system according to the position conversion matrix; obtaining the straight line direction vector of the puncture needle in the first coordinate system according to the position information of the point, and obtaining the corresponding posture information.

[0046] In some embodiments, taking the above experiment using the abdominal phantom as an example, the method of unifying the puncture needle posture includes: considering the actual surgical puncture needle structure, where the posture unification is to realize the unification of the direction of the needle tip. Through the positions of the two passive balls, the direction information of the current posture is obtained, which is also the direction of the puncture needle. According to the direction information, the position information of another point in the direction of the needle tip is obtained, and combined with the position transfer matrix T1, the position coordinates of the corresponding point in the image coordinate system can be obtained, thereby realizing the corresponding posture unification.

[0047] The direction vector of the straight line in the phantom coordinate system 1 can be obtained by vx=x1-x;vy=y1-y;vz=z1-z. Since the vector is unchanged in different coordinate systems, according to the spatial straight line equation, the coordinates R(x, y, z) of another point of P(x, y, z) in the direction vector are obtained, and the corresponding coordinates in the current coordinate system are:

[0048] R1(x, y, z) = T1*R(x, y, z)

[0049] From this, the posture information in the corresponding coordinate system can be obtained.

[0050] Referring to Figure 3 , in the NDI coordinate system, the coordinate information of points A, B, and O can be obtained. Since the puncture needle is a straight straight one, we simulate the dashed line TP as the puncture needle and convert it to the virtual human body coordinate system to unify the position and posture. Each coordinate point corresponds to the coordinate in the virtual human body coordinate system, which can be directly obtained by , for example, . Here, the posture calculation according to the AB posture directly obtains the posture of TP,

[0051] ;

[0052] According to the position information of PT, a line is drawn in the virtual human body in real time for correspondence, thereby achieving posture unification.

[0053] In some embodiments, the needle tip of the operation puncture needle is punctured at the center of each marker point; the method for positioning and tracking a plurality of passive balls arranged on the puncture needle by the optical device to obtain the position information of the passive balls in the second coordinate system comprises: stopping the needle tip at the center of each marker point for several seconds, and obtaining a plurality of position information at each center point, and averaging the position information to obtain the position information of the center point of each marker point. This embodiment adopts error feedback compensation: due to manual point-by-point workpiece, there will be certain errors, including hand jitter, marker size and the like, which will cause the error to be large. In order to reduce the above errors, the five-second sampling method is adopted to obtain the position information of the marker point. Since the points under the optical device are real-time fluctuations, we determine the position information of the center of each marker point by stopping at the center of each marker point for 5 seconds, and sampling 5 position information at each center point position, and averaging. To a certain extent, the error can be effectively reduced.

[0054] Referring to Figure 4 , the embodiment of the present application also provides a puncture needle space pose unification system for realizing the puncture needle space pose unification method, comprising: a puncture needle 100 comprising a body and a plurality of passive balls arranged on the body; a puncture object 200 comprising an object body and a plurality of marker points arranged on the body; an optical device 300 for positioning and tracking the passive balls; and a CT imaging module 400 for CT imaging of the puncture object.

[0055] Referring to Figure 5 , the CT imaging device, the abdominal phantom, the puncture needle, the optical device and the computer are set on site. During the experiment, we verify the position registration information by drawing balls, and we use the puncture needle to point a position point information on the phantom, and obtain the position information of the corresponding point at the position in the image through the obtained position transfer matrix. By drawing a ball with a radius of 2 pixels at the corresponding position in the image, it is confirmed whether the position transfer matrix is correct.

[0056] At the same time, in order to verify the workpiece direction information, a ball is drawn at the needle tip and another point in the direction of the needle tip, and in order to facilitate display, the radius of the balls is uniformly 5 pixels, and the straight line between the two balls is visualized to check the corresponding direction information.

[0057] While specific embodiments are described herein, one of ordinary skill in the art will recognize that many other modifications or alternative embodiments can be within the scope of the present disclosure. For example, any of the functions and / or processing capabilities described in connection with a particular device or component can be performed by any other device or component. Additionally, while various illustrative implementations and architectures have been described in accordance with embodiments of the present disclosure, one of ordinary skill in the art will recognize that many other modifications to the illustrative implementations and architectures described herein are also within the scope of the present disclosure.

[0058] It should be appreciated that the method steps in the embodiments of the application can be implemented or carried out by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer readable memory. The methods can use standard programming techniques. Each program can be implemented in a high level procedural or object oriented programming language to communicate with a computer system. However, the programs can be implemented in assembly or machine language, if desired. In any case, the language can be a compiled or interpreted language. Also, the programs can be stored in a proprietary or open format that permits the programs to run on multiple platforms. Furthermore, the programs can be run on a proprietary or open platform.

[0059] Further, the operations of the processes described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The processes described herein (or variations and / or combinations thereof) can be implemented under the control of one or more computer systems configured with executable instructions (e.g., computer programs, one or more computer programs, or one or more applications) to perform the operations of the processes, by hardware, or combinations thereof. The computer programs include machine instructions that can be executed by one or more microprocessors.

[0060] Further, the methods can be implemented in any type of computing platform operably coupled to a suitable computing platform, including but not limited to a personal computer, a mini-computer, a mainframe, a workstation, a network or distributed computing environment, a stand-alone or integrated computer platform, or in communication with a charged particle tool or other imaging device, and the like. Aspects of the present application can be implemented in machine readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, an optical read and / or write storage medium, RAM, ROM, and the like, such that it can be read by a programmable computer to configure and operate the computer to perform the processes described herein when the storage medium or device is read by the computer. In addition, the machine readable code, or portions thereof, can be transmitted over a wired or wireless network. The present application includes these and other different types of non-transitory computer readable storage media when such media include instructions or programs that implement the steps described above in conjunction with a microprocessor or other data processor. The present application also includes the computer itself when programmed in accordance with the methods and techniques described herein.

[0061] The computer program can be applied to input data to perform the functions described herein to transform the input data to generate output data that is stored to non-volatile memory. The output information can also be applied to one or more output devices, such as a display. In a preferred embodiment of the present application, the transformed data represents a physical and tangible object, including a particular visual depiction of a physical and tangible object produced on a display.

[0062] The embodiments of the present application described above are merely exemplary and those skilled in the art will readily understand that various modifications to the embodiments can be made without departing from the spirit and scope of the present application.

Claims

1. A method for spatial pose unification of a puncture needle, characterized in that, The method comprises the following steps: obtaining first position information of a landmark point of a puncture object in a first coordinate system; wherein an abdominal phantom is used as the puncture object; positioning second position information of the landmark point in a second coordinate system by operating a puncture needle; obtaining a position transfer matrix according to the first position information and the second position information; position unifying the puncture needle based on the position transfer matrix; obtaining second direction information of the puncture needle in the second coordinate system; obtaining attitude information of the puncture needle in the first coordinate system according to the second direction information and the position transfer matrix; wherein the positioning of the second position information of the landmark point in the second coordinate system by operating the puncture needle comprises: operating a needle tip point of the puncture needle at the center of each landmark point; positioning and tracking a plurality of passive small balls arranged on the puncture needle by an optical device to obtain third position information of the passive small balls in the second coordinate system; and obtaining the second position information of the landmark point in the second coordinate system according to the third position information and the structure of the puncture needle; the positioning and tracking of the plurality of passive small balls arranged on the puncture needle by the optical device to obtain the third position information of the passive small balls in the second coordinate system comprises: stopping the needle tip at the center point of each landmark point for several seconds, obtaining a plurality of center point position information at each center point, and obtaining the third position information of the center point of each landmark point by averaging the plurality of center point position information corresponding to each center point; the obtaining of the attitude information of the puncture needle in the first coordinate system according to the second direction information and the position transfer matrix comprises: obtaining a direction vector in the second direction information, and obtaining position information of a point on the direction vector; obtaining position information of the point in the first coordinate system according to the position transfer matrix; obtaining a straight line direction vector of the puncture needle in the first coordinate system according to the position information of the point, and obtaining corresponding attitude information.

2. The puncture needle space pose unification method of claim 1, wherein, the obtaining of the position information of the landmark point of the puncture object in the first coordinate system comprises: obtaining original data containing information of the landmark point by CT imaging; segmenting the landmark point by a medical image segmentation algorithm to obtain position information of each landmark point in the first coordinate system.

3. The puncture needle space pose unification method of claim 1, wherein, the structure of the puncture needle is a Y-shaped structure comprising a pen body and a split needle tip; the plurality of passive small balls comprise first, second, third and fourth passive small balls; and the method further comprises: establishing a rectangular coordinate system with the needle tip of the puncture needle as the origin and the pen body as the X-axis to obtain a third coordinate system; wherein the first and second passive small balls are located on the X-axis.

4. The puncture needle space pose unification method of claim 1, wherein, the position unifying of the puncture needle based on the position transfer matrix comprises: obtaining fourth position information of the passive small balls in the first coordinate system according to the third position information of the passive small balls of the puncture needle in the second coordinate system and the position transfer matrix.

5. The puncture needle space pose unification method of claim 3, wherein, The second direction information of the puncture needle in the second coordinate system comprises: According to the position information of the first passive ball and the second passive ball in the second coordinate system, the second direction information of the puncture needle in the second coordinate system is obtained.

6. A puncture needle spatial pose unification system for implementing the puncture needle spatial pose unification method of any one of claims 1 to 5, characterized in that, Comprise: Puncture needle, comprising a body and a plurality of passive balls arranged on the body; Puncture object, comprising an object body and a plurality of marker points arranged on the body; wherein an abdominal phantom is used as the puncture object; Optical equipment for positioning and tracking the passive ball; CT imaging module for CT imaging of the puncture object; Wherein, the second position information of the marker points in the second coordinate system by operating the puncture needle includes: operating the needle tip point of the puncture needle at the center of each marker point; the third position information of the passive ball in the second coordinate system is obtained by positioning and tracking the passive ball arranged on the puncture needle through the optical equipment; according to the third position information and the structure of the puncture needle, the second position information of the marker points in the second coordinate system is obtained; The third position information of the passive ball in the second coordinate system is obtained by positioning and tracking the passive ball arranged on the puncture needle through the optical equipment, which comprises: stopping the needle tip at the center point of each marker point for several seconds, and acquiring several center point position information at each center point, and taking the average of several center point position information corresponding to each center point to obtain the third position information of the center point of each marker point; According to the second direction information and the position transfer matrix, the attitude information of the puncture needle in the first coordinate system is obtained, which comprises: obtaining the direction vector in the second direction information, and obtaining the position information of a point on the direction vector; according to the position transfer matrix, the position information of the point in the first coordinate system is obtained; according to the position information of the point, the straight line direction vector of the puncture needle in the first coordinate system is obtained, and the corresponding attitude information is obtained.

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