WO2021227548A1

WO2021227548A1 - Digital guide system for mandibular osteotomy

Info

Publication number: WO2021227548A1
Application number: PCT/CN2021/072835
Authority: WO
Inventors: 孟偲; 李曲恒
Original assignee: 北京航空航天大学
Priority date: 2020-05-12
Filing date: 2021-01-20
Publication date: 2021-11-18
Also published as: CN111658065A

Abstract

Disclosed in the present invention is a digital guide system for mandibular osteotomy, mainly for use in accurately observing the relative positions of a surgical instrument and a mandibular surgical site, reducing the surgical difficulty, and improving the surgical quality. A surgical instrument and the mandible are observed at the same time by means of a visual tracker, the relative position relationship between the end of the surgical instrument and a mandibular surgical site is visually displayed on a display screen, a position change of the mandible is monitored by means of the visual tracker, and the position of a three-dimensional model of the mandible in VR is corrected in real time; thus, not only can the actual cutting position during surgery be accurately compared with a cutting position planned before the surgery to obtain the consistency therebetween, but also the problems of a narrow surgical view, inconvenience in direct observation, and inability to accurately determine the relative positions of the surgical instrument and the mandible during mandibular osteotomy can be solved, the error between surgery implementation and planned surgery can be quantified, thereby improving the surgical quality.

Description

A digital guidance system for mandibular cutting surgery

Technical field

The invention relates to the technical field of computer-assisted medical treatment, in particular to a digital guidance system for mandibular cutting operations.

Background technique

At present, computer-assisted medical treatment has become a trend in medical operations.

In the existing mandibular cutting operation, firstly, the three-dimensional image of the patient’s skull is obtained by CT to reconstruct the overall three-dimensional model of the mandible; then, the mandible model is 3D printed out as a physical model, and both sides are aligned on the physical model. The buccal position needs to be cut for surgical planning, and the trajectory of surgical cutting and trimming is drawn; finally, after verification on the physical model, the actual operation is performed on the recipient. In the actual operation process, the external appearance or skin of the recipient cannot be destroyed, and the part to be operated can only be exposed by peeling the gums inside the oral cavity, and then holding the surgical instrument for the operation.

The above-mentioned mandibular cutting surgery has the following defects: (1) Due to the special surgical site, surgical access and surgical instruments of the mandible, the doctor's field of view and observation angle are greatly restricted, which can only be determined by experience and limited observation The relative position of the surgical instrument and the jawbone is prone to large errors or even mistakes; (2) Due to the lack of accurate measurement methods, it is impossible to ensure the symmetry of the trajectory of the left cheek bone and the right cheek bone, which often results in postoperative Jaws are asymmetry or limited in symmetry; (3) Preoperative CT images are only used to build a three-dimensional geometric model of the skull or mandible.

Summary of the invention

In view of this, the present invention provides a digital guidance system for mandibular cutting surgery to solve the problem of the limited operation field of view due to the special surgical site of the mandible, which leads to errors in judging the relative position of the surgical instrument and the mandible. problem.

The present invention provides a digital guidance system for mandibular cutting surgery, including: a global camera support (1), a visual tracker (2) fixedly connected to the global camera support (1), and the visual tracker (2) ) Electrically connected graphic workstation (3), surgical instrument optical tracking mark (4) pasted on the surgical instrument, and tooth fixed connection mark (5) fixedly connected to the mandibular teeth; among them,

The global camera bracket (1) is used to support and fix the visual tracker (2) and adjust the viewing angle direction of the visual tracker (2);

The visual tracker (2) is used to detect and track the optical tracking mark (4) of the surgical instrument during the operation, and track the posture of the surgical instrument by detecting and tracking the fixed connection mark of the tooth (5). ) Realize the detection and tracking of the mandible's position and posture, and send the posture detection and tracking information of the surgical instrument and the posture detection and tracking information of the mandible to the graphics workstation (3);

The graphics workstation (3) is used to run medical image processing software to generate a three-dimensional model of the mandible from the medical CT scan image of the mandible; run the medical image navigation IGS software for mandibular cutting surgery to import and display in the VR display environment The three-dimensional model of the mandible, the surgical cutting plan and the virtual surgical instrument; the real visual space and the medical image space are registered and registered through the fixed connection mark (5) of the teeth; the update is updated according to the received posture detection and tracking information of the surgical instrument The position and posture of the virtual surgical instrument is updated according to the received posture detection and tracking information of the mandible to update the posture of the three-dimensional model of the mandible.

In a possible implementation manner, the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention further includes: an electromagnetic tracker (6) electrically connected to the graphics workstation (3);

The electromagnetic tracker (6) is used to monitor the posture change of the mandible during the operation, and send the posture change information of the mandible to the graphics workstation (3); wherein, the mandible is located during the operation Within the working range of the electromagnetic tracker;

The graphics workstation (3) is used to comprehensively receive the posture detection and tracking information of the mandible and the posture change information of the mandible, and update the posture of the three-dimensional model of the mandible.

In a possible implementation manner, the digital guidance system for mandibular cutting surgery provided by the present invention further includes: augmented reality glasses (7) wirelessly connected to the graphics workstation (3);

The augmented reality glasses (7) are used to superimpose and display the three-dimensional models of the mandible and the mandible, superimpose and display surgical instruments and virtual surgical instruments, and display a surgical cutting plan.

In a possible implementation manner, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, the vision tracker (2) is a binocular stereo vision optical measurement system.

In a possible implementation manner, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, the surgical instrument optical tracking mark (4) is a combined mark composed of three X corner points.

In a possible implementation, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, the fixed tooth connection mark (5) is a soft mark containing at least three metal points (8), The gap between the teeth of the mandible is sleeved on the teeth of the mandible; the metal point (8) is visible by the visual tracker (2) during the operation and is visible in the medical CT scan image.

In a possible implementation manner, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, the graphics workstation (3) is specifically used to fix the metal points on the mark (5) through the teeth (8) Correspondence between the spatial coordinates in the visual tracker (2) and the medical CT scan image respectively to realize the registration and registration of the real visual space and the medical image space.

In a possible implementation manner, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, the graphics workstation (3) is also used to send out when the posture change of the mandible exceeds a set threshold Alarm prompt sound; when the posture of the surgical instrument end exceeds the allowable error of the surgical cutting plan during the operation, the alarm prompt sound will be emitted.

The digital guidance system for the mandibular cutting operation provided by the present invention is mainly used for accurately observing the relative posture of the surgical instrument and the mandibular surgical site, reducing the difficulty of the operation and improving the quality of the operation. Simultaneously observe the surgical instruments and the mandible through the visual tracker, and visually display the relative position relationship between the end of the surgical instrument and the surgical site of the mandible on the display screen, and monitor the posture changes of the mandible through the visual tracker, and make real-time corrections. The pose of the three-dimensional model of the mandible in VR can not only accurately compare the consistency of the actual cutting position during the operation with the planned cutting position before the operation, but also solve the narrow operation field of view, inconvenience of direct observation and inaccuracy during the mandibular cutting operation. The problem of determining the relative position of the surgical instrument and the mandible can quantify the error between the implementation of the operation and the planned operation, thereby improving the quality of the operation.

Description of the drawings

Fig. 1 is a schematic structural diagram of a digital guidance system for mandibular cutting surgery provided by an embodiment of the present invention;

Fig. 2 is a working flow chart of a digital guidance system for mandibular cutting surgery provided by an embodiment of the present invention.

Description of reference signs: 1. Global camera support; 2. Vision tracker; 3. Graphic workstation; 4. Optical tracking mark for surgical instruments; 5. Teeth fixed connection mark; 6. Electromagnetic tracker; 7. Augmented reality glasses; 8. , Metal points.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are merely examples and are not intended to limit the present application.

An embodiment of the present invention provides a digital guidance system for mandibular cutting surgery, as shown in FIG. 1, including: a global camera bracket 1, a visual tracker 2 fixedly connected to the global camera bracket 1, and a visual tracker 2 electrical The connected graphic workstation 3, the surgical instrument optical tracking mark 4 pasted on the surgical instrument, and the tooth fixed connection mark 5 fixedly connected to the mandibular teeth; among them,

The global camera bracket 1 is used to support and fix the visual tracker 2 and adjust the viewing angle of the visual tracker 2;

The visual tracker 2 is used to detect and track the posture of the surgical instrument by detecting and tracking the optical tracking mark 4 of the surgical instrument during the operation, and to achieve the detection and tracking of the mandible by detecting and tracking the fixed connection mark 5 of the tooth. And send the posture detection and tracking information of the surgical instruments and the posture detection and tracking information of the mandible to the graphics workstation 3;

Graphics workstation 3, used to run medical image processing software, generate a three-dimensional model of the mandible from medical CT (Computed Tomograph) scan images of the mandible; run the IGS (Image Guidance Surgery) software for mandibular cutting surgery medical image navigation , Import and display the three-dimensional model of the mandible, surgical cutting plan and virtual surgical instruments in the VR (Virtual Reality) display environment; register the real visual space with the medical image space through the fixed connection mark 5 of the tooth; according to the received operation The posture detection and tracking information of the instrument, the posture of the virtual surgical instrument is updated, and the posture of the three-dimensional model of the mandible is updated according to the received posture detection and tracking information of the mandible.

In specific implementation, the digital guidance system for mandibular cutting surgery provided by the present invention may further include: an electromagnetic tracker 6 electrically connected to the graphics workstation 3; the electromagnetic tracker 6 can monitor the mandible during the operation The posture change of the mandible is sent to the graphics workstation 3; the posture change information of the mandible monitored by the electromagnetic tracker 6 can be used at certain moments, such as due to surgical instruments or doctors during the operation. When the limbs are blocked and the fixed connection mark 5 of the teeth cannot be observed, it is a supplement to the visual tracker 2 to detect the posture information of the mandible. In this way, the graphics workstation 3 can comprehensively receive the posture detection and tracking information of the mandible and the information of the mandible. Posture change information, update the posture of the three-dimensional model of the mandible, which can further ensure the safety and accuracy of the operation. It should be noted that during the operation, the mandible needs to be within the working range of the electromagnetic tracker. In this way, the movement of the mandible will cut the magnetic lines of the electromagnetic tracker 6 so that the electromagnetic tracker 6 can monitor the position of the mandible. Variations, specifically, the electromagnetic tracker 6 can be placed on the operating table close to the mandible.

In specific implementation, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, it may also include: augmented reality glasses 7 wirelessly connected to the graphics workstation 3; during the operation, the augmented reality glasses 7 are worn on On the doctor’s head, the doctor can observe the real mandible and surgical instruments through the augmented reality glasses 7, and the augmented reality glasses 7 can also display the three-dimensional model of the mandible, the surgical cutting plan and the virtual surgical instruments sent by the graphics workstation 3. The three-dimensional model of bone and mandible is superimposed and displayed. Surgical instruments and virtual surgical instruments are superimposed and displayed. In this way, the doctor can observe the mandible and the position to be cut in perspective, avoiding the doctor's diversion during the operation to observe the VR display of the graphics workstation 3 And affect the accuracy of surgery.

In specific implementation, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, the global camera bracket may be a triangular camera bracket. It should be noted that once the viewing angle of the visual tracker is determined, it remains still during the operation.

In specific implementation, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, the visual tracker can use the MicronTracker binocular stereo vision optical measurement system. Of course, the visual tracker can also be other types of visual trackers that can perform detection and tracking, which is not limited here.

In specific implementation, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, the mandibular cutting surgery medical image navigation IGS software running on the graphics workstation can be the general medical operation software Mimics, or it can also be a dedicated surgery The planning software is not limited here.

In specific implementation, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, the optical tracking mark for surgical instruments can use the combined mark composed of three X angle points used by the MicronTracker binocular stereo vision optical measurement system. Identify different surgical instruments. Of course, the optical tracking mark of the surgical instrument may also be another type of mark capable of optical tracking, and it is not limited here.

In specific implementation, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, as shown in FIG. 1, the tooth fixed connection mark 5 may be a soft mark containing at least three metal points 8. It can be sleeved on the teeth of the mandible through the gap between the teeth of the mandible. The metal spot 8 can be detected and tracked by the visual tracker 2 during the operation, and the metal spot 8 is visible in the medical CT scan image.

In specific implementation, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, as shown in FIG. 1, the graphics workstation 3 can fix the metal points 8 on the mark 5 through the teeth fixed on the visual tracker 2 and the medical The correspondence of the spatial coordinates in the CT scan image realizes the registration and registration of the real visual space and the medical image space, so that the doctor can observe the relative pose relationship between the surgical object and the surgical instrument in a unified coordinate system space.

In specific implementation, in the above-mentioned digital guidance system for mandibular cutting surgery provided by the present invention, the graphics workstation can also sound an alarm when the posture change of the mandible exceeds a set threshold; moreover, it can also be used during the operation. When the posture of the end of the middle surgical instrument exceeds the error allowed by the surgical cutting plan, an alarm will sound, so that the safety and accuracy of the operation can be improved.

It should be noted that in the above-mentioned solution provided by the present invention, the model or style of the global camera bracket is changed, the binocular stereo optical tracker is changed, the optical tracking mark of the surgical instrument is changed, and the number of mark points on the fixed connection mark of the tooth is changed. All belong to the scope of the present invention.

The specific work flow of the digital guidance system for the mandibular cutting operation provided by the present invention will be described in detail below. As shown in Figure 2, firstly, the fixed connection mark 5 of the tooth is fixedly connected to the mandibular teeth of the patient and the patient is kept still. The processing software generates a three-dimensional model of the mandible; then, the generated three-dimensional model of the mandible is input into the VR environment of the mandibular cutting operation medical image navigation IGS software of the graphics workstation 3 for display, and the doctor performs the surgical planning (that is, confirms the surgical cutting Entry point, cutting surface and cutting trajectory) and determine the three-dimensional coordinates of the mark on the fixed tooth connection mark 5 in the medical image space. Record the coordinates of the mark point in the medical image space as

Then, the subject wears the fixed tooth connection mark 5 (to ensure that the position is consistent with the CT scan) lying on the operating table to prepare for the operation, the visual tracker 2 obtains the mark on the fixed tooth connection mark 5 in the visual tracker 2 Three-dimensional coordinates (denoted as

From the three-dimensional coordinates of the marks on the teeth fixed connection mark 5 in the visual tracker 2 and their corresponding three-dimensional coordinates in the medical image space, the registration matrix from the real physical space to the medical image space is solved for T _{C}→{IGS} , Should meet

Finally, the doctor holds the surgical instrument pasted with the surgical instrument optical tracking mark 4 to perform the mandibular cutting operation on the recipient.

Specifically, when a doctor holds a surgical instrument pasted with a surgical instrument optical tracking mark 4 to perform a mandibular cutting operation on a subject, it is specifically implemented in the following manner: First, the doctor inserts the surgical instrument into the mandible in the recipient’s mouth to prepare the mandible At the surgical position, the visual tracker 2 detects the position of the surgical instrument in real time through the optical tracking mark 4 of the surgical instrument, and according to the detected position of the surgical instrument, it uses the registration matrix T _{{C}→{IGS} to} change the position of the surgical instrument. The posture is transformed into the medical image space to update the posture of the virtual surgical instrument in the IGS; then, the doctor adjusts the posture of the surgical instrument and observes the relative position of the virtual surgical instrument, the three-dimensional model of the mandible, and the surgical planning position in the IGS After the actual operation cutting position is consistent with the planned cutting position, the actual surgical cutting will start; finally, during the operation, the visual tracker 2 will also detect and track the position and attitude change of the mandible by detecting and tracking the fixed connection mark 5 of the teeth. Once it is found that the posture change of the mandible exceeds the set threshold, an alarm will sound to remind the doctor that the actual position of the mandible has moved, and the posture of the three-dimensional model of the mandible in the IGS software will be corrected in real time to ensure the operation process The accuracy of the relative pose between the middle surgical instrument and the mandible.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. In this way, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

A digital guidance system for mandibular cutting surgery, characterized by comprising: a global camera support (1), a visual tracker (2) fixedly connected to the global camera support (1), and the visual tracker ( 2) Electrically connected graphic workstation (3), surgical instrument optical tracking mark (4) pasted on the surgical instrument, and tooth fixed connection mark (5) fixedly connected to the mandibular teeth; among them,

The global camera bracket (1) is used to support and fix the visual tracker (2) and adjust the viewing angle direction of the visual tracker (2);

The visual tracker (2) is used to detect and track the optical tracking mark (4) of the surgical instrument during the operation, and track the posture of the surgical instrument by detecting and tracking the fixed connection mark of the tooth (5). ) Realize the detection and tracking of the mandible's position and posture, and send the posture detection and tracking information of the surgical instrument and the posture detection and tracking information of the mandible to the graphics workstation (3);

The graphics workstation (3) is used to run medical image processing software to generate a three-dimensional model of the mandible from the medical CT scan image of the mandible; run the medical image navigation IGS software for mandibular cutting surgery to import and display in the VR display environment The three-dimensional model of the mandible, the surgical cutting plan and the virtual surgical instrument; the real visual space and the medical image space are registered and registered through the fixed connection mark (5) of the teeth; the update is updated according to the received posture detection and tracking information of the surgical instrument The position and posture of the virtual surgical instrument is updated according to the received posture detection and tracking information of the mandible to update the posture of the three-dimensional model of the mandible.
The digital guidance system for mandibular cutting surgery according to claim 1, further comprising: an electromagnetic tracker (6) electrically connected to the graphics workstation (3);

The electromagnetic tracker (6) is used to monitor the posture change of the mandible during the operation, and send the posture change information of the mandible to the graphics workstation (3); wherein, the mandible is located during the operation Within the working range of the electromagnetic tracker;

The graphics workstation (3) is used to comprehensively receive the posture detection and tracking information of the mandible and the posture change information of the mandible, and update the posture of the three-dimensional model of the mandible.
The digital guidance system for mandibular cutting surgery according to claim 1, further comprising: augmented reality glasses (7) wirelessly connected to the graphics workstation (3);

The augmented reality glasses (7) are used to superimpose and display the three-dimensional models of the mandible and the mandible, superimpose and display surgical instruments and virtual surgical instruments, and display the surgical cutting plan.
The digital guidance system for mandibular cutting surgery according to claim 1, wherein the visual tracker (2) is a binocular stereo vision optical measurement system.
The digital guidance system for mandibular cutting surgery according to claim 1, wherein the optical tracking mark (4) of the surgical instrument is a combined mark composed of three X corner points.
The digital guidance system for mandibular cutting surgery according to claim 1, characterized in that the fixed tooth connection mark (5) is a soft mark containing at least three metal points (8), which passes between the teeth of the mandible The gap is sleeved on the teeth of the mandible; the metal point (8) is visible by the visual tracker (2) during the operation and is visible in the medical CT scan image.
The digital guidance system for mandibular cutting surgery according to claim 6, characterized in that the graphic workstation (3) is specifically used to fix the metal points (8) on the markings (5) through the teeth. The correspondence between the visual tracker (2) and the spatial coordinates in the medical CT scan image realizes the registration and registration of the real visual space and the medical image space.
The digital guidance system for mandibular cutting surgery according to any one of claims 1 to 7, characterized in that the graphics workstation (3) is also used to send out when the posture change of the mandible exceeds a set threshold Alarm prompt sound; when the posture of the surgical instrument end exceeds the allowable error of the surgical cutting plan during the operation, the alarm prompt sound will be emitted.