Ultrasonic probe planning and positioning method based on three-dimensional ct image

Abstract

The invention discloses an ultrasonic probe planning and positioning method based on a three-dimensional ct image. The method comprises the following steps: S1, acquiring a preoperative CT image; s2, marking a key anatomical structure and an operation target; s3, determining probe types and parameters; s4, planning a probe track; s5, simulating ultrasonic imaging; s6, positioning and tracking in the operation; and S7, performing three-dimensional registration. The invention belongs to the technical field of spinal interventional surgical navigation, and relates to the technical field of spinal interventional surgical navigation. Based on a three-dimensional CT image, not only is an operation planned, but also ultrasonic probe positioning is planned before the operation; the preoperative probe track can be modeled and planned through CT information to ensure that the key spine structure is recorded; by planning the scanning track of the ultrasonic probe based on the CT image before the operation, the operation procedure can be optimized, and the unnecessary detection time in the operation can be reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of spinal intervention surgery navigation, and specifically refers to a method for planning and positioning an ultrasound probe based on three-dimensional CT images. Background Art

[0002] With the aging of the population, bone and joint diseases pose a serious threat to human health and are one of the most serious diseases causing disability. When physical and drug treatments are ineffective, spinal interventional surgery is needed to correct spinal deformities and maintain their structural stability, among which spinal fusion surgery is a common method. In current clinical practice, image navigation systems (IGS) provide key surgical assistance functions. Most navigation systems use optical tracking cameras as tracking devices and use reflective balls fixed on surgical instruments as tracked tools to locate their spatial positions in the surgical area. Optical tracking positioning is required to establish an accurate spatial transformation relationship between the intraoperative anatomical structure and the preoperative three-dimensional CT image, which generally requires complicated manual operations and registration point acquisition, which not only requires a long surgical exposure time, but is also limited by limited registration accuracy.

[0003] The use of intraoperative CT has potential radiation risks, high costs and high surgical complexity, and there is an urgent need to develop safer and more efficient image navigation technologies other than intraoperative CT. Summary of the invention

[0004] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a method for planning and positioning an ultrasound probe based on three-dimensional CT images, which plans the scanning trajectory of the ultrasound probe before surgery and optimizes the intraoperative positioning operation process and time.

[0005] The technical solution adopted by the present invention is as follows: The present invention provides a method for planning and positioning an ultrasound probe based on three-dimensional CT images, comprising the following steps:

[0006] S1. Obtain preoperative CT images: obtain high-resolution three-dimensional spinal imaging data of the patient through CT scanning and store it;

[0007] S2. Marking key anatomical structures and surgical targets: Use image processing software to segment the CT images, mark the key anatomical structures of the spine, and determine the surgical target area;

[0008] S3. Determine the probe type and parameters: Select the appropriate ultrasound probe type and parameters according to surgical needs.

[0009] After determining the geometric parameters and imaging characteristics of the probe, so as to simulate ultrasound imaging in CT images;

[0010] S4. Probe trajectory planning: simulate the scanning process of the ultrasound probe in the CT image to determine the best probe approach and scanning trajectory; optimize the imaging effect by adjusting the probe angle, position and scanning depth;

[0011] S5. Simulated ultrasound imaging: The imaging process of the ultrasound probe is simulated in the CT image to generate a virtual ultrasound image, which can help surgeons understand the imaging effects under different trajectories before surgery and choose the best path. Use acoustic simulation tools to simulate the propagation of ultrasound in spinal tissue, predict signal attenuation and phase distortion, and thus evaluate the imaging quality of different paths;

[0012] S6. Intraoperative positioning and tracking: Combined with the preoperative probe trajectory planning in the above steps, the probe is placed and corrected in real time. The probe is tracked in real time through the optical tracking system, and ultrasound images are collected and recorded in real time and transmitted to the computer. At the same time, the position of the ultrasound probe is recorded;

[0013] S7. Three-dimensional registration: The images obtained by ultrasound and CT are registered and then fused for three-dimensional presentation.

[0014] The beneficial effects achieved by the present invention using the above scheme are as follows: This scheme provides a method for planning and positioning an ultrasound probe based on three-dimensional CT images. Based on the three-dimensional CT images, not only the surgery is planned before the surgery, but also the positioning of the ultrasound probe is planned; the preoperative probe trajectory can be modeled and planned through CT information to ensure that key spinal structures are recorded; by planning the scanning trajectory of the ultrasound probe based on CT images before the surgery, the surgical operation process can be optimized and unnecessary detection time during the operation can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is the flow chart of this program; DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0017] Example

[0018] The present invention provides a method for planning and positioning an ultrasound probe based on three-dimensional CT images, comprising the following steps:

[0019] S1. Obtain preoperative CT images: Obtain high-resolution three-dimensional spinal image data of the patient through CT scanning and store it in a DICOM format or other medical imaging format. Preprocess the CT images, such as removing noise and enhancing contrast, so as to more clearly display the spinal structure.

[0020] S2. Marking key anatomical structures and surgical targets: Use medical image processing software (such as 3D Slicer, Mimics) to segment CT images and mark key anatomical structures of the spine, such as vertebral bodies, intervertebral discs, nerve roots, etc.; determine the surgical target area, such as a specific vertebral body or intervertebral space;

[0021] S3. Determine the probe type and parameters: Select the appropriate ultrasound probe type (such as linear array probe, convex array probe) and parameters (such as frequency, field of view) according to surgical needs;

[0022] Specifically, for spinal areas with greater imaging depth, such as the lumbar spine and part of the thoracic spine, such as vertebroplasty, spinal fusion, and scoliosis correction, a low-frequency (2-5MHz) convex array probe is used. For spinal areas with medium imaging depth, such as part of the thoracic spine and cervical spine, which are used in cervical discectomy and spinal canal decompression, a medium-frequency (5-10MHz) linear array probe is used for more precise viewing;

[0023] After determining the geometric parameters and imaging characteristics of the probe, so as to simulate ultrasound imaging in CT images;

[0024] S4. Plan the probe trajectory: simulate the scanning process of the ultrasound probe in the CT image to determine the best probe approach and scanning trajectory; consider the anatomical structure of the spine and the convenience of surgical operation, plan the starting point, end point and path of the probe to ensure that the target area can be covered and important nerves and blood vessels can be avoided; optimize the imaging effect by adjusting the probe angle, position and scanning depth;

[0025] Common surgical incisions include ventral approach, posterior approach, and lateral approach. Ultrasound scanning is performed along the spine and perpendicular to the spine, avoiding the wound. The angle of the probe is rotated to obtain three-dimensional information of the key surgical cone and surrounding soft tissue information.

[0026] During the ventral approach, the ultrasound probe can be placed along the midline or lateral abdomen of the patient. The scanning path should cover the anterior area of ​​the target vertebral body. The longitudinal or transverse scanning path can be used, and the angle of the probe can be adjusted as needed.

[0027] During the posterior approach, the ultrasound probe can be placed along the midline of the patient's spine or close to both sides of the spine, and the scanning path can be longitudinal (along the long axis of the spine) or transverse (across the vertebral body) to obtain the best imaging angle. The spinal cord and nerve roots are observed in real time to confirm the decompression effect and ensure the accuracy of screw implantation;

[0028] During the lateral approach, the ultrasound probe is usually placed along the lateral waist. The probe should be kept at the position closest to the target area to obtain clear imaging. It can be scanned longitudinally or obliquely from the patient's side to cover the lateral side of the target vertebra and the intervertebral disc area.

[0029] S5. Simulated ultrasound imaging: The imaging process of the ultrasound probe is simulated in the CT image to generate a virtual ultrasound image. This can help surgeons understand the imaging effects under different trajectories before surgery and choose the best path; use acoustic simulation tools such as k-Wave and Field II to simulate the propagation of ultrasound in spinal tissue, predict signal attenuation and phase distortion, and thus evaluate the imaging quality of different paths;

[0030] S6. Intraoperative positioning and tracking: Combined with the preoperative probe trajectory planning in the above steps, the probe is placed and corrected in real time. The probe is tracked in real time by the optical tracking system, and the position and orientation of the ultrasound probe in three-dimensional space can be accurately determined. The ultrasound image is collected and recorded in real time and transmitted to the computer. At the same time, the position and orientation of the ultrasound probe are tracked and recorded in real time by the optical tracking system.

[0031] S7. Three-dimensional registration: The images acquired by ultrasound and CT are registered, and then fused for three-dimensional presentation. Specifically, this implementation step refers to the patent previously applied for by the applicant, a method and device for cross-modal image registration of CT and ultrasound, application number 202411214115.0.

[0032] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0033] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0034] The present invention and its implementation methods are described above, and such description is not restrictive. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design structures and embodiments similar to the technical solution without creativity, which should all fall within the protection scope of the present invention.

Claims

1. A method for planning and positioning an ultrasound probe based on three-dimensional CT images, characterized in that: The steps include: S1. Obtain preoperative CT images: obtain high-resolution three-dimensional spinal imaging data of the patient through CT scanning and store it; S2. Marking key anatomical structures and surgical targets: Use image processing software to segment the CT images, mark the key anatomical structures of the spine, and determine the surgical target area; S3. Determine the probe type and parameters: Select the appropriate ultrasound probe type and parameters according to the surgical needs; S4. Probe trajectory planning: simulate the scanning process of the ultrasound probe in the CT image to determine the best probe approach and scanning trajectory; optimize the imaging effect by adjusting the probe angle, position and scanning depth; S5. Simulated ultrasound imaging: simulate the imaging process of the ultrasound probe in the CT image, generate virtual ultrasound images, understand the imaging effects under different trajectories, and select the best path; use acoustic simulation tools to simulate the propagation of ultrasound in spinal tissue, predict signal attenuation and phase distortion, and thus evaluate the imaging quality of different paths; S6. Intraoperative positioning and tracking: Combined with the preoperative probe trajectory planning in the above steps, the probe is placed and corrected in real time. The probe is tracked in real time through the optical tracking system, and ultrasound images are collected and recorded in real time and transmitted to the computer. At the same time, the position of the ultrasound probe is recorded; S7. Three-dimensional registration: The images obtained by ultrasound and CT are registered and then fused for three-dimensional presentation.

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