Transcranial magnetic stimulation high-precision positioning method, device and equipment based on optical navigation

Abstract

The invention relates to a transcranial magnetic stimulation high-precision positioning method, device and equipment based on optical navigation. Comprising the steps of selecting non-coplanar reference points based on a three-dimensional brain model of a patient, obtaining image coordinates and physical coordinates of all the reference points, carrying out corresponding point matching through the image coordinates and the physical coordinates, calculating and generating an optimal rigid transformation matrix, carrying out target registration error calculation, and realizing registration of an image coordinate system and a physical coordinate system. And according to the registered brain tissue conductivity parameters, calculating electric field space distribution induced by the transcranial magnetic stimulation coil in a target brain area, dynamically correcting stimulation target point coordinates of the virtual coil, and according to a completed coordinate system registration result, dynamically displaying the position and direction of the virtual coil corresponding to the transcranial magnetic stimulation coil on the three-dimensional brain model. And synchronously updating the brain slice view based on the corrected target point coordinates, and highlighting the actually stimulated brain region boundary. According to the method, adaptive neural navigation is driven through electric field remapping, and compensation target point correction is achieved.

Description

Technical Field

[0001] The present application relates to the field of medical technology, and in particular to a method, device and equipment for high-precision positioning of transcranial magnetic stimulation based on optical navigation. Background Art

[0002] With the rapid advancement of neuroscience technology, transcranial magnetic stimulation (TMS)-based treatments and research are gaining increasing attention in the medical field. However, traditional TMS treatments suffer from insufficient precision in brain positioning and stimulation parameter adjustment, lack efficient data processing capabilities, and rely heavily on hardware resources (such as memory and graphics cards) (requiring at least 32GB of memory). Furthermore, traditional technologies only support importing a single data format, making it difficult to generate personalized stimulation plans. The coil position adjustment method is limited, resulting in limited treatment accuracy and operational flexibility.

[0003] Current transcranial magnetic stimulation navigation systems face multiple technical bottlenecks: First, due to the insufficient positioning accuracy of traditional optical cameras, there is a significant deviation between the model and the actual spatial registration, causing the stimulation target to often deviate from the intended brain area; second, in the processing of complex three-dimensional brain models, the system relies on high-configuration hardware and still cannot meet the real-time computing needs, and the low data processing efficiency restricts the smoothness of operation; in addition, compatibility limitations mean that it only supports a limited variety of brain scan data formats, which cannot adapt to the diverse clinical image import scenarios; at the same time, the lack of operational flexibility is manifested in the lack of a dual-mode adjustment mechanism that coordinates manual fine-tuning and mechanical control, making it difficult to dynamically respond to real-time needs during treatment. These factors collectively limit the depth and breadth of the system's clinical application in precise neuromodulation. Summary of the Invention

[0004] The present application provides a high-precision transcranial magnetic stimulation positioning method based on optical navigation, which is characterized by comprising: Based on the patient's three-dimensional brain model, non-coplanar reference points are selected to obtain the image coordinates and physical coordinates of all reference points; By matching corresponding points between image coordinates and physical coordinates, the optimal rigid transformation matrix is ​​calculated and the target registration error is calculated to achieve registration between the image coordinate system and the physical coordinate system. Based on the registered brain tissue conductivity parameters, the spatial distribution of the electric field induced by the transcranial magnetic stimulation coil in the target brain area is calculated, and the stimulation target coordinates of the virtual coil are dynamically corrected; Based on the completed coordinate system registration results, the position and orientation of the virtual coil corresponding to the transcranial magnetic stimulation coil are dynamically displayed on the three-dimensional brain model. The brain slice view is synchronously updated based on the corrected target coordinates and the boundaries of the actual stimulated brain area are highlighted.

[0005] Optionally, selecting non-coplanar reference points based on the patient's three-dimensional brain model and obtaining the image coordinates and physical coordinates of all reference points includes: Manually selecting non-coplanar reference points on the patient's head, wherein the reference points are at least four and not located on the same plane; Before surgery, manually mark the center positions of all reference points on the patient's three-dimensional brain model to obtain the three-dimensional coordinates of each point in the imaging coordinate system; During the operation, the optical tracking system is used to track and collect the real-time physical coordinates of the same set of reference points in the surgical space.

[0006] Optionally, the matching of corresponding points between the image coordinates and the physical coordinates, calculating and generating an optimal rigid transformation matrix, and calculating the target registration error to achieve registration between the image coordinate system and the physical coordinate system includes: The uniqueness of the reference points is used to achieve the matching of the image coordinates and physical coordinates of all reference points, and the parameters are optimized based on the least squares method; Through optimization calculation, the spatial transformation relationship with the minimum reference point position deviation after the image coordinate system is converted to the physical coordinate system is obtained, and the optimal rigid transformation matrix is ​​generated; Based on the generated optimal rigid transformation matrix, the mean deviation between the physical position and the transformed position of all reference points is calculated and evaluated.

[0007] Optionally, the step of calculating the spatial distribution of the electric field induced by the transcranial magnetic stimulation coil in the target brain area based on the registered brain tissue conductivity parameters and dynamically correcting the stimulation target coordinates of the virtual coil includes: Obtain brain tissue layer conductivity parameters, time-varying current and spatial position vector, and generate magnetic vector potential through calculation; Use the coil electric field calculation formula on the magnetic vector potential to generate the electric field strength; The coil electric field calculation formula is: ; in, is the total electric field strength, is the electric potential gradient, is the negative time derivative of the potential magnetic vector potential; The peak value of the electric field intensity is obtained as the actual stimulation target point, and compared with the predetermined target point coordinates to generate an offset correction value.

[0008] Optionally, the method dynamically displays the position and orientation of the virtual coil corresponding to the transcranial magnetic stimulation coil on the three-dimensional brain model based on the completed coordinate system registration result, synchronously updates the brain slice view based on the corrected target coordinates, and highlights the boundaries of the brain area actually stimulated, including: The optical tracking system acquires the physical coil pose data in real time, maps it to the image space of the 3D brain model through the optimal rigid transformation matrix, and dynamically generates a synchronized virtual coil model. Based on the target coordinates of the virtual coil, coronal, sagittal, and transverse anatomical slices passing through the target and orthogonal to each other are generated, and the covered target brain area is dynamically highlighted in the slices; Based on the real-time calculated electric field distribution, the boundaries of the brain areas actually stimulated are dynamically highlighted in the brain slice view; When the deviation between the electric field peak position and the predetermined target point exceeds the clinical threshold, coil posture adjustment guidance is generated.

[0009] Optionally, obtaining brain tissue layer conductivity parameters, time-varying current, and spatial position vector, and generating magnetic vector potential by calculation, includes: Based on the time-varying current and the position of the target point relative to the coil, the magnetic vector potential generated by the coil current in space is calculated using the magnetic vector potential calculation formula; The magnetic vector potential calculation formula is: in, is the magnetic vector potential, is the permeability of free space, is the applied time-varying current in the TMS coil, and To indicate the position of a point in space relative to the coil, is the path integral along the coil wire.

[0010] Optionally, the optical navigation-based transcranial magnetic stimulation high-precision positioning method is characterized by further comprising: By setting the unique ID and spatial position relationship of the benchmark points, all benchmark points can be uniquely identified; The image coordinates with the same identity and physical coordinates Perform matching to form a coordinate data set; Based on the offset of the overall position in the coordinate data set, the least square method is used to generate the transformation parameters that minimize the overall deviation; Use the theoretical coordinate transformation calculation formula for each reference point to obtain the minimum possible value of the sum of squared distances and generate the optimal rigid transformation matrix; The theoretical coordinate transformation calculation formula is: ; in, For the The homogeneous coordinate representation of the image coordinates of the reference points, is the theoretical coordinate in the physical coordinate system after transformation, is the optimal rigid transformation matrix; The target registration error calculation formula is used to calculate the root mean square value of all reference point deviations to generate the target registration error, which is then compared with the set clinical threshold to obtain the evaluation conclusion. The target registration error calculation formula is: ; in, For the The measured coordinates of the physical coordinate system of the reference point, For the The theoretical coordinates after the image coordinates of the reference points are converted, is the optimal rigid transformation matrix, is the target registration error.

[0011] The present application also provides a transcranial magnetic stimulation high-precision positioning device based on optical navigation, characterized in that the device comprises: A fiducial point sampling module is used to select non-coplanar fiducial points based on the patient's three-dimensional brain model and obtain the image coordinates and physical coordinates of all fiducial points; The rigid matching module is used to match corresponding points between image coordinates and physical coordinates, calculate and generate the optimal rigid transformation matrix, and calculate the target registration error to achieve registration between the image coordinate system and the physical coordinate system; The electric field remapping module is used to calculate the spatial distribution of the electric field induced by the transcranial magnetic stimulation coil in the target brain area based on the registered brain tissue conductivity parameters, and dynamically correct the stimulation target coordinates of the virtual coil; The stimulation domain visualization module is used to dynamically display the position and orientation of the virtual coil corresponding to the transcranial magnetic stimulation coil on the three-dimensional brain model based on the completed coordinate system alignment results. It also synchronously updates the brain slice view based on the corrected target coordinates and highlights the boundaries of the brain area actually stimulated.

[0012] Optionally, the electric field remapping module further includes: Magnetic potential field calculation module, used to calculate the spatial magnetic vector potential distribution through the magnetic vector potential calculation formula; Conductivity building block, used to construct a hierarchical model of brain tissue conductivity; The electric field solving module is used to calculate the electric field strength using the coil electric field calculation formula; The target dynamic correction module is used to locate the electric field peak coordinates and generate an offset vector by comparing with the original target point.

[0013] The present application also provides an electronic device, characterized in that it is used to implement the optical navigation-based transcranial magnetic stimulation high-precision positioning method described in any one of claims 1 to 7, comprising: Medical imaging scanning equipment for generating raw data of a patient's three-dimensional brain model and providing coordinates of reference points in an imaging coordinate system; Optical positioning tracking equipment, used to collect the physical coordinate system coordinates of the reference points in real time and track the spatial position of the transcranial magnetic stimulation coil; Transcranial magnetic stimulation coils for non-invasive neuromodulation and dynamic mapping of driving virtual coils in 3D brain models; A processor for performing all computationally intensive tasks to implement a high-precision transcranial magnetic stimulation positioning method based on optical navigation; Memory is used to store processor executable instructions and static storage data.

[0014] The beneficial effects of the present application are as follows: the present application realizes submillimeter coordinate system registration through image-physical coordinate mapping of non-coplanar reference points and rigid transformation matrix calculation, significantly improving the positioning accuracy of the stimulation target; based on the layered conductivity parameters of brain tissue, the electric field spatial distribution is calculated in real time by the finite element method, and the stimulation target coordinates are dynamically corrected, breaking through the deep target positioning deviation caused by tissue conduction differences in traditional rigid navigation; and the three-dimensional brain model dynamic mapping and multi-plane slice real-time update are driven by the registration results, combined with the highlighting of the actual stimulated brain area boundary after electric field correction, to ensure smooth operation in a low-configuration hardware environment; and the coil posture automatic correction guidance driven by the electric field peak is compatible with the parsing interface of multiple types of brain scan formats and the manual / mechanical dual-mode control mechanism, synchronously responding to the dynamic adjustment needs in clinical operations, and building a therapeutic closed loop of adaptive electric field navigation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required in the embodiments or the description of the prior art. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0016] Figure 1 A flowchart showing an embodiment of a method for high-precision transcranial magnetic stimulation positioning based on optical navigation disclosed in the present application is shown; Figure 2 A schematic diagram showing reference points of an embodiment of a high-precision transcranial magnetic stimulation positioning method based on optical navigation disclosed in the present application; Figure 3 A schematic diagram showing a position display of an embodiment of a high-precision transcranial magnetic stimulation positioning method based on optical navigation disclosed in the present application; Figure 4A structural block diagram of an embodiment of a high-precision transcranial magnetic stimulation positioning method based on optical navigation disclosed in this application is shown. DETAILED DESCRIPTION

[0017] Various exemplary embodiments, features, and aspects of the present application will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise indicated.

[0018] The terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0019] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0020] In addition, numerous specific details are provided in the detailed description below to better illustrate the present application. Those skilled in the art will appreciate that the present application can be practiced without certain specific details. In some instances, methods, means, components, and circuits well known to those skilled in the art are not described in detail in order to highlight the main purpose of the present application.

[0021] This application proposes a high-precision transcranial magnetic stimulation positioning method based on optical navigation, which is used to solve the problems of deep target positioning deviation, inefficient data processing, distortion of stimulation range visualization, compatibility limitations and poor operational flexibility caused by traditional rigid navigation due to ignoring tissue conductivity differences. By establishing an image and physical coordinate mapping of non-coplanar reference points, the optimal rigid transformation matrix is ​​calculated to achieve precise alignment of the coordinate system. Based on the conductivity parameters of the brain tissue after alignment, the electric field distribution induced by the coil is calculated in real time using the Bio-Savart law and the finite element method, and the coordinates of the stimulation target are dynamically corrected. The system uses the alignment results to dynamically display the virtual position and direction of the transcranial magnetic stimulation coil in a three-dimensional brain model, synchronously updates the brain slice view based on the target coordinates after the electric field correction, and highlights the boundaries of the actual stimulated brain area. While ensuring the precise match between the model and the actual space, this application significantly improves data processing efficiency, expands the compatibility of brain scan formats, and integrates manual and mechanical control dual-mode adjustment mechanisms to meet the needs of dynamic clinical operations.

[0022] Example 1 like Figure 1FIG. 1 is a flow chart of a method for high-precision transcranial magnetic stimulation positioning based on optical navigation according to an embodiment of the present application, which specifically includes the following contents: S100 , based on the patient's three-dimensional brain model, non-coplanar reference points are selected, and the image coordinates and physical coordinates of all the reference points are obtained.

[0023] Specifically, based on the patient's 3D brain model, at least four non-coplanar fiducial points (such as the nasion, tragus, and cranial vertex landmarks) with distinct spatial locations are selected. Their spatial distribution must satisfy the mathematical completeness conditions of a rigid transformation. The image coordinate system coordinates of the fiducial points are extracted from medical images (CT / MRI). Simultaneously, the physical coordinate system coordinates are obtained in the patient's head using surface landmarks or the tip of a surgical instrument. The fiducial points in these two coordinate systems form a spatial mapping.

[0024] S200 , by matching corresponding points between the image coordinates and the physical coordinates, an optimal rigid transformation matrix is ​​calculated and generated, and target registration error is calculated to achieve registration between the image coordinate system and the physical coordinate system.

[0025] Specifically, the optimal rigid transformation matrix is ​​generated by matching the corresponding points between the image coordinates and the physical coordinates, and the registration accuracy is verified based on the target registration error to achieve spatial mapping from the image coordinate system to the physical coordinate system that meets neurosurgery standards.

[0026] S300, based on the registered brain tissue conductivity parameters, calculate the spatial distribution of the electric field induced by the transcranial magnetic stimulation coil in the target brain area, and dynamically correct the stimulation target coordinates of the virtual coil.

[0027] Specifically, based on the aligned brain tissue layer conductivity parameters (scalp / skull / cerebrospinal fluid), the finite element method is used to calculate in real time the three-dimensional electric field spatial distribution induced by the transcranial magnetic stimulation coil in the target brain area, and the stimulation target coordinates of the virtual coil are dynamically corrected according to the peak position of the electric field intensity.

[0028] S400: Based on the completed coordinate system registration results, the virtual coil position and direction corresponding to the transcranial magnetic stimulation coil are dynamically displayed on the three-dimensional brain model. The brain slice view is synchronously updated based on the corrected target coordinates and the boundaries of the brain area actually stimulated are highlighted.

[0029] Specifically, according to the coordinate system registration results, the real-time position of the transcranial magnetic stimulation coil is dynamically mapped in the three-dimensional brain model, and the multi-plane brain slice view is synchronously updated based on the target coordinates corrected in step S300, while highlighting the anatomical boundaries of the brain area actually stimulated by the electric field.

[0030] In summary, this application constructs a spatial registration system for non-coplanar fiducials. By selecting at least four spatially distinct body landmarks (such as the nasal root, tragus, and skull vertex), precise coordinate data for both the imaging and physical coordinate systems is simultaneously acquired, forming control point pairs that meet rigid transformation completeness requirements. This non-coplanar fiducial layout effectively avoids registration singularities caused by coplanar points, laying a geometric foundation for submillimeter spatial mapping and fundamentally addressing the positioning deviation issues inherent in traditional solutions due to flawed fiducial distribution. Secondly, a rigid transformation-driven registration verification architecture is designed. The optimal rigid transformation matrix is ​​generated by matching corresponding points between the image and physical coordinates, and registration accuracy is dynamically verified based on the target registration error (TRE). This architecture ensures that the conversion process from the imaging coordinate system to the physical coordinate system consistently meets neurosurgical precision standards, completely eliminating the risk of stimulation target offset due to coordinate mapping inaccuracies and providing rigid spatial transformation guarantees for precise neuromodulation. Then, overcoming the limitations of traditional rigid navigation, layered conductivity modeling and finite element method solutions to the electric field equation dynamically correct target coordinate offsets caused by tissue penetration attenuation, resolving the industry challenge of upward focal shift in deep brain regions such as the dorsolateral prefrontal cortex. Finally, an optical tracker is used to capture the coil's physical position in real time, converting it into imaging coordinate parameters using a rigid transformation matrix. A fully synchronized virtual coil is then dynamically rendered within the 3D brain model. Orthogonal anatomical slice planes (coronal, sagittal, and transverse) are automatically determined by the virtual coil's axial direction, enabling real-time updates of brain slice views. This mechanism instantly translates the physician's operating intent into multi-dimensional visual navigation, forming a millisecond-level closed loop between physical operation and virtual display, significantly improving target positioning efficiency and operational reliability in complex clinical scenarios.

[0031] As an implementation method, in step S100, non-coplanar reference points are selected based on the patient's three-dimensional brain model, and the image coordinates and physical coordinates of all the reference points are obtained, including: S101, manually selecting non-coplanar reference points on the patient's head, wherein the reference points are at least four and are not located on the same plane.

[0032] Specifically, through manual marking by a doctor, four points with different spatial positions are selected on the surface of the patient's head as reference points. The reference points are not in the same anatomical plane to ensure that the spatial distribution of the reference points meets the geometric non-coplanar constraints required for rigid transformation.

[0033] Among them, in neurosurgery, the reference points are usually surface markers and the tips of surgical instruments. The surface markers are infrared reflective balls or electromagnetic positioning markers on the patient's head, and the tips of surgical instruments are positioned in real time by optical tracking devices.

[0034] S102 , before surgery, manually mark the center positions of all reference points on the patient's three-dimensional brain model to obtain the three-dimensional coordinates of each point in the image coordinate system.

[0035] Specifically, such as Figure 2 As shown, before surgery, the doctor manually locates and annotates the anatomical center of the fiducials selected in step S101 in the patient's 3D brain model reconstructed based on CT / MRI data. The coordinate extraction function of medical image processing software (such as 3DSlicer) accurately obtains the 3D coordinates of each fiducial in the image coordinate system.

[0036] S103 , during the operation, the optical tracking system is used to track and collect the real-time physical coordinates of the same set of reference points in the operating space.

[0037] Specifically, during surgery, an optical tracking system (such as NDI Polaris) uses a positioning probe or reflective ball to collect the physical coordinates of the patient's head reference points in the actual surgical space in real time. Using the operating room's fixed coordinate system as a reference, the system uses an infrared camera to capture the spatial position of the reflective markers. Combined with the probe's geometric calibration parameters, the system outputs 3D physical coordinates with millimeter-level accuracy.

[0038] This process needs to be performed on the same set of reference points as the image coordinate acquisition in step S102 .

[0039] As an implementation method, in step S200, the image coordinate system and the physical coordinate system are aligned by matching corresponding points between the image coordinate system and the physical coordinate system, calculating and generating an optimal rigid transformation matrix, and performing target registration error calculation, including: S201 , achieving matching between the image coordinates and the physical coordinates of all reference points through the uniqueness of the reference points, and performing parameter optimization based on the least squares method.

[0040] Specifically, based on the unique anatomical identifiers of the fiducials (e.g., specific surface marker locations), the preoperatively annotated image coordinates are precisely matched point-by-point with the intraoperatively acquired physical coordinates to form a one-to-one corresponding spatial coordinate dataset. Using a least-squares optimization algorithm, the rotation and translation parameters are iteratively calculated to minimize the overall deviation between the actual physical position of all fiducials and their theoretically transformed positions.

[0041] Among them, by setting the unique ID and spatial position relationship of the reference point, all reference points can be uniquely identified, and the image coordinates with the same identification can be and physical coordinates Matching is performed to form a coordinate data set, and based on the offset of the overall position in the coordinate data set, the least squares method is used to generate the conversion parameters that meet the minimum overall deviation.

[0042] S202, through optimization calculation, obtain the spatial transformation relationship with the minimum reference point position deviation after the image coordinate system is transformed into the physical coordinate system, and generate the optimal rigid transformation matrix.

[0043] Specifically, an optimal rigid transformation matrix is ​​generated based on the optimized spatial correspondence. This matrix, composed of three-dimensional rotation parameters and three-dimensional translation parameters, can transform the coordinates of any point in the image coordinate system into theoretical coordinates in the physical coordinate system. The transformation process strictly maintains the rigid body properties of the spatial structure (i.e., the distances and angles between points remain unchanged), achieving conformal mapping between image space and physical space.

[0044] Among them, the theoretical coordinate transformation calculation formula is used for each reference point to obtain the minimum possible value of the sum of the squares of the distances and generate the optimal rigid transformation matrix. The theoretical coordinate transformation calculation formula is: ; As stated, For the The homogeneous coordinate representation of the image coordinates of the reference points, is the theoretical coordinate in the physical coordinate system after transformation, is the optimal rigid transformation matrix.

[0045] S203: Based on the generated optimal rigid transformation matrix, the mean deviation between the physical positions and the transformed positions of all reference points is calculated and evaluated.

[0046] Specifically, the generated rigid transformation matrix is ​​used to calculate the theoretical coordinates of all fiducials in physical space and compare them with the actual coordinates measured by the optical tracking system. Registration accuracy is quantitatively assessed by calculating the mean spatial distance between the theoretical and actual values ​​for each point (i.e., the target registration error, TRE). This error is compared in real time with a clinical safety threshold for neurosurgery (typically 2 mm). If the error is below the threshold, registration is considered valid and the navigation phase begins. If it exceeds the threshold, an alarm is triggered, prompting re-registration.

[0047] Among them, the target registration error calculation formula is used to calculate the root mean square value of the deviation of all reference points to generate the target registration error, which is compared with the set clinical threshold to obtain the evaluation conclusion. The target registration error calculation formula is: ; As stated, For the The measured coordinates of the physical coordinate system of the reference point, For the The theoretical coordinates after the image coordinates of the reference points are converted, is the optimal rigid transformation matrix, is the target registration error.

[0048] As an implementation method, in step S300, the spatial distribution of the electric field induced by the transcranial magnetic stimulation coil in the target brain area is calculated based on the registered brain tissue conductivity parameters, and the stimulation target coordinates of the virtual coil are dynamically corrected, including: S301, obtaining brain tissue layer conductivity parameters, time-varying current, and spatial position vector, and generating magnetic vector potential through calculation.

[0049] Specifically, by integrating multi-source input parameters to build an electromagnetic calculation foundation, the standardized or personalized conductivity values ​​of the scalp layer (high conductivity), skull layer (ultra-low conductivity), and cerebrospinal fluid layer (high conductivity) are loaded to form a real spatial conduction model of bio-electromagnetic characteristics; by connecting to the pulse current waveform function output by the transcranial magnetic stimulation device, the instantaneous intensity and time-varying characteristics of the coil driving current are characterized; by capturing the physical position of the coil based on the optical tracking system and combining it with the aligned brain model spatial coordinate system, the three-dimensional spatial vector of the target brain area relative to the coil conductor is determined; finally, according to the Bio-Savart law, the coil conductor path is spatially integrated to calculate the magnetic vector potential field excited by the time-varying current at the target position.

[0050] The magnetic vector potential generated by the coil current in space is calculated based on the time-varying current and the position of the target point relative to the coil using the magnetic vector potential calculation formula. The magnetic vector potential calculation formula is: in, is the magnetic vector potential, is the permeability of free space, is the applied time-varying current in the TMS coil, and To indicate the position of a point in space relative to the coil, is the path integral along the coil wire.

[0051] S302 , using the coil electric field calculation formula for the magnetic vector potential to generate the electric field intensity.

[0052] Specifically, the time partial derivative of the magnetic vector potential function output in step S301 is calculated, and the electric field control equation is constructed in combination with the brain tissue conductivity parameter. The finite element method is used to iteratively solve the equation on the brain tissue grid nodes, and the electric field intensity vector of each point in the three-dimensional space is output.

[0053] The coil electric field calculation formula is: ; in, is the total electric field strength, is the electric potential gradient, is the negative time derivative of the potential magnetic vector potential; S303: Obtain the peak value of the electric field intensity as the actual stimulation target point, and compare it with the predetermined target point coordinates to generate an offset correction value.

[0054] Specifically, by scanning the three-dimensional electric field intensity distribution calculated in step S302, the coordinates of the electric field intensity peak (i.e., the position with the highest probability of neuronal depolarization) are identified as the actual physiological stimulation target, and the Euclidean distance between the actual target and the preset target (based on anatomical landmark settings) is calculated. If the distance exceeds the clinically allowed threshold (typical value 2 mm), a spatial offset vector pointing from the preset target to the actual target is generated.

[0055] As an implementation method, in step S400, based on the completed coordinate system registration result, the virtual coil position and orientation corresponding to the transcranial magnetic stimulation coil are dynamically displayed on the three-dimensional brain model, and the brain slice view is synchronously updated based on the corrected target coordinates and the boundary of the actual stimulated brain area is highlighted, including: S401, based on the optical tracking system, the physical coil posture data is acquired in real time, mapped to the image space of the three-dimensional brain model through the optimal rigid transformation matrix, and a synchronized virtual coil model is dynamically generated.

[0056] Specifically, such as Figure 3 As shown, the pose data of the physical coil is captured in real time by an optical tracker, and the rigid transformation matrix T generated in step S202 is applied to convert the physical pose into image coordinate system parameters, and a fully synchronized virtual coil is dynamically rendered in the three-dimensional brain model. The spatial position and axial angle of the virtual coil are strictly consistent with those of the physical coil.

[0057] S402 , generating coronal, sagittal, and transverse anatomical slices that pass through the target and are orthogonal to each other based on the target coordinates of the virtual coil, and dynamically highlighting the covered target brain area in the slices.

[0058] Specifically, such as Figure 3 As shown, based on the target coordinates of the virtual coil tip in image space, three orthogonal anatomical planes are automatically determined: the coronal, sagittal, and transverse planes. The coronal plane is parallel to the frontal-occipital line, the sagittal plane is parallel to the plane separating the left and right hemispheres, and the transverse plane is parallel to the skull base-top line. Three-plane tomographic images passing through the target are extracted and rendered in real time from the 3D brain model. The target brain area (such as the primary motor cortex) covered by the stimulation field is dynamically highlighted. As the operator adjusts the physical coil, all views are synchronously refreshed within milliseconds, forming a closed-loop feedback loop.

[0059] Operators can manually adjust the coil position by dragging a control slider or button with the mouse. The slice view on the right will highlight the target area, and keyboard shortcuts are supported for quick fine-tuning. External mechanical devices can be controlled and moved according to instructions, with the position display linked to the actual device to control the coil position.

[0060] S403 , based on the real-time calculated electric field distribution, dynamically highlighting the boundary of the brain region actually stimulated in the brain slice view.

[0061] Specifically, based on the electric field intensity distribution data calculated in real time in step S302, the field intensity values ​​of different brain regions are extracted. By setting the electric field intensity threshold for neuronal activation, the anatomical contours of the brain regions that meet the threshold are filled with highlighted colors, and the boundaries are refreshed in real time as the coil moves.

[0062] S404: When the deviation between the electric field peak position and the predetermined target point exceeds a clinical threshold, a coil posture adjustment guide is generated.

[0063] Specifically, when the target offset determined in step S303 continuously exceeds the clinical threshold (e.g., 2 mm), it is determined that the current coil position needs to be adjusted. A translation vector is generated by calculating the direction of the line connecting the actual target and the preset target, and the electric field distribution is analyzed. If focal distortion exists, a rotation angle recommendation is generated.

[0064] Example 2 Based on the same principle as the above method, a high-precision transcranial magnetic stimulation positioning method based on optical navigation is also proposed, see Figure 4 A high-precision transcranial magnetic stimulation positioning device 100 based on optical navigation according to an embodiment of the present disclosure includes: A reference point sampling module 110 is used to select non-coplanar reference points based on the patient's three-dimensional brain model and obtain the image coordinates and physical coordinates of all reference points; The rigid matching module 120 is used to match corresponding points between the image coordinates and the physical coordinates, calculate and generate the optimal rigid transformation matrix, and calculate the target registration error to achieve registration between the image coordinate system and the physical coordinate system; The electric field remapping module 130 is used to calculate the spatial distribution of the electric field induced by the transcranial magnetic stimulation coil in the target brain area based on the registered brain tissue conductivity parameters, and dynamically correct the stimulation target coordinates of the virtual coil; The stimulation domain visualization module 140 is used to dynamically display the virtual coil position and direction corresponding to the transcranial magnetic stimulation coil on the three-dimensional brain model based on the completed coordinate system alignment results, and synchronously update the brain slice view based on the corrected target coordinates and highlight the boundaries of the brain area actually stimulated.

[0065] As an optional implementation scheme of the present application, optionally, the electric field remapping module 130 further includes: The magnetic potential field calculation module 131 is used to calculate the spatial magnetic vector potential distribution using the magnetic vector potential calculation formula; Conductivity construction module 132, for constructing a brain tissue conductivity layered model; The electric field solving module 133 is used to calculate and generate the electric field strength using the coil electric field calculation formula; The target point dynamic correction module 134 is used to locate the electric field peak coordinates and compare them with the original target point to generate an offset vector.

[0066] Obviously, those skilled in the art should understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program. The program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned control methods. The modules or steps of the present invention can be implemented by a general-purpose computing device. They can be concentrated on a single computing device or distributed on a network composed of multiple computing devices. Alternatively, they can be implemented by program codes executable by the computing device, so that they can be stored in a storage device and executed by the computing device, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. In this way, the present invention is not limited to any specific combination of hardware and software.

[0067] Those skilled in the art will appreciate that all or part of the processes in the above-described embodiments can be implemented by instructing the relevant hardware through a computer program. The program can be stored in a computer-readable storage medium. When executed, the program can include the processes of the above-described control method embodiments. The storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD). The storage medium can also include a combination of the above-mentioned types of memory.

[0068] Example 3 Furthermore, the present application proposes an electronic device, characterized in that it is used to implement any of the above-mentioned high-precision transcranial magnetic stimulation positioning methods based on optical navigation, comprising: Medical imaging scanning equipment for generating raw data of a patient's three-dimensional brain model and providing coordinates of reference points in an imaging coordinate system; Optical positioning tracking equipment, used to collect the physical coordinate system coordinates of the reference points in real time and track the spatial position of the transcranial magnetic stimulation coil; Transcranial magnetic stimulation coils for non-invasive neuromodulation and dynamic mapping of driving virtual coils in 3D brain models; A processor for performing all computationally intensive tasks to implement a high-precision transcranial magnetic stimulation positioning method based on optical navigation; Memory is used to store processor executable instructions and static storage data.

[0069] Medical imaging scanners, serving as the data source for spatial modeling of the patient's brain, generate the raw tomographic image sequences (such as DICOM data from CT / MRI) needed to construct a 3D brain model. Image processing software then extracts the precise 3D coordinates of fiducials within the image coordinate system. The coordinate data output by the device forms the image spatial reference for spatial registration.

[0070] As a real-time acquisition system for surgical spatial coordinates, the optical positioning tracking device is used to track the millimeter-level coordinates of the patient's head fiducials during surgery and simultaneously capture the six-degree-of-freedom spatial position (3D position + 3-axis orientation) of the transcranial magnetic stimulation coil. The dynamic coordinate data stream it outputs provides physical space motion parameters for coordinate system registration and navigation mapping.

[0071] The transcranial magnetic stimulation coil acts as a neuromodulator and navigation feedback vehicle. It delivers non-invasive brain stimulation therapy through a time-varying magnetic field. Its spatial position data also drives the real-time dynamic mapping of a virtual coil within a 3D brain model. During treatment, the device simultaneously performs both physical manipulation and virtual navigation.

[0072] It should be noted that the number of processors can be one or more. Furthermore, the electronic device in the embodiments of the present disclosure may also include an input device and an output device. The processor, memory, input device, and output device may be connected via a bus or other means, which are not specifically limited herein.

[0073] The memory, as a computer-readable storage medium for the data-driven large language model performance prediction system, can be used to store software programs, computer executable programs, and various modules, such as the program or module corresponding to the optical navigation-based transcranial magnetic stimulation high-precision positioning method in the disclosed embodiment. The processor executes the software programs or modules stored in the memory to perform various functional applications and data processing in the electronic device.

[0074] The embodiments of the present application have been described above. The above description is illustrative and not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or improvements to the technology in the market, or to enable other persons skilled in the art to understand the embodiments disclosed herein.

Claims

1. A high-precision transcranial magnetic stimulation positioning method based on optical navigation, characterized in that: include: Based on the patient's three-dimensional brain model, non-coplanar reference points are selected to obtain the image coordinates and physical coordinates of all reference points; By matching corresponding points between image coordinates and physical coordinates, the optimal rigid transformation matrix is ​​calculated and the target registration error is calculated to achieve registration between the image coordinate system and the physical coordinate system. Based on the registered brain tissue conductivity parameters, the spatial distribution of the electric field induced by the transcranial magnetic stimulation coil in the target brain area is calculated, and the stimulation target coordinates of the virtual coil are dynamically corrected; Based on the completed coordinate system registration results, the position and orientation of the virtual coil corresponding to the transcranial magnetic stimulation coil are dynamically displayed on the three-dimensional brain model. The brain slice view is synchronously updated based on the corrected target coordinates and the boundaries of the actual stimulated brain area are highlighted.

2. The method for high-precision transcranial magnetic stimulation positioning based on optical navigation according to claim 1, characterized in that: The method of selecting non-coplanar reference points based on the patient's three-dimensional brain model and obtaining the image coordinates and physical coordinates of all reference points includes: Manually selecting non-coplanar reference points on the patient's head, wherein the reference points are at least four and not located on the same plane; Before surgery, manually mark the center positions of all reference points on the patient's three-dimensional brain model to obtain the three-dimensional coordinates of each point in the imaging coordinate system; During the operation, the optical tracking system is used to track and collect the real-time physical coordinates of the same set of reference points in the surgical space.

3. The method for high-precision transcranial magnetic stimulation positioning based on optical navigation according to claim 1, wherein: The method of matching corresponding points between the image coordinates and the physical coordinates, calculating and generating the optimal rigid transformation matrix, and calculating the target registration error to achieve registration between the image coordinate system and the physical coordinate system includes: The uniqueness of the reference points is used to achieve the matching of the image coordinates and physical coordinates of all reference points, and the parameters are optimized based on the least squares method; Through optimization calculation, the spatial transformation relationship with the minimum reference point position deviation after the image coordinate system is converted to the physical coordinate system is obtained, and the optimal rigid transformation matrix is ​​generated; Based on the generated optimal rigid transformation matrix, the mean deviation between the physical position and the transformed position of all reference points is calculated and evaluated.

4. The method for high-precision transcranial magnetic stimulation positioning based on optical navigation according to claim 1, wherein: The method of calculating the spatial distribution of the electric field induced by the transcranial magnetic stimulation coil in the target brain area based on the registered brain tissue conductivity parameters and dynamically correcting the stimulation target coordinates of the virtual coil includes: Obtain brain tissue layer conductivity parameters, time-varying current and spatial position vector, and generate magnetic vector potential through calculation; Use the coil electric field calculation formula on the magnetic vector potential to generate the electric field strength; The coil electric field calculation formula is: ； in, is the total electric field strength, is the electric potential gradient, is the negative time derivative of the potential magnetic vector potential; The peak value of the electric field intensity is obtained as the actual stimulation target point, and compared with the predetermined target point coordinates to generate an offset correction value.

5. The method for high-precision transcranial magnetic stimulation positioning based on optical navigation according to claim 1, wherein: The method includes dynamically displaying the position and orientation of the virtual coil corresponding to the transcranial magnetic stimulation coil on the three-dimensional brain model based on the completed coordinate system registration results, synchronously updating the brain slice view based on the corrected target coordinates, and highlighting the boundaries of the actual stimulated brain area, including: The optical tracking system acquires the physical coil pose data in real time, maps it to the image space of the 3D brain model through the optimal rigid transformation matrix, and dynamically generates a synchronized virtual coil model. Based on the target coordinates of the virtual coil, coronal, sagittal, and transverse anatomical slices passing through the target and orthogonal to each other are generated, and the covered target brain area is dynamically highlighted in the slices; Based on the real-time calculated electric field distribution, the boundaries of the brain areas actually stimulated are dynamically highlighted in the brain slice view; When the deviation between the electric field peak position and the predetermined target point exceeds the clinical threshold, coil posture adjustment guidance is generated.

6. The method for high-precision transcranial magnetic stimulation positioning based on optical navigation according to claim 4, characterized in that: The method of obtaining brain tissue layered conductivity parameters, time-varying current, and spatial position vector, and generating magnetic vector potential by calculation, includes: Based on the time-varying current and the position of the target point relative to the coil, the magnetic vector potential generated by the coil current in space is calculated using the magnetic vector potential calculation formula; The magnetic vector potential calculation formula is: in, is the magnetic vector potential, is the permeability of free space, is the applied time-varying current in the TMS coil, and To indicate the position of a point in space relative to the coil, is the path integral along the coil wire.

7. The method for high-precision transcranial magnetic stimulation positioning based on optical navigation according to claim 3, characterized in that: Also includes: By setting the unique ID and spatial position relationship of the benchmark points, all benchmark points can be uniquely identified; The image coordinates with the same identity and physical coordinates Perform matching to form a coordinate data set; Based on the offset of the overall position in the coordinate data set, the least square method is used to generate the transformation parameters that minimize the overall deviation; Use the theoretical coordinate transformation calculation formula for each reference point to obtain the minimum possible value of the sum of squared distances and generate the optimal rigid transformation matrix; The theoretical coordinate transformation calculation formula is: ； in, For the The homogeneous coordinate representation of the image coordinates of the reference points, is the theoretical coordinate in the physical coordinate system after transformation, is the optimal rigid transformation matrix; The target registration error calculation formula is used to calculate the root mean square value of all reference point deviations to generate the target registration error, which is then compared with the set clinical threshold to obtain the evaluation conclusion. The target registration error calculation formula is: ； in, For the The measured coordinates of the physical coordinate system of the reference point, For the The theoretical coordinates after the image coordinates of the reference points are converted, is the optimal rigid transformation matrix, is the target registration error.

8. A high-precision transcranial magnetic stimulation positioning device based on optical navigation, characterized in that: The device comprises: A fiducial point sampling module is used to select non-coplanar fiducial points based on the patient's three-dimensional brain model and obtain the image coordinates and physical coordinates of all fiducial points; The rigid matching module is used to match corresponding points between image coordinates and physical coordinates, calculate and generate the optimal rigid transformation matrix, and calculate the target registration error to achieve registration between the image coordinate system and the physical coordinate system; The electric field remapping module is used to calculate the spatial distribution of the electric field induced by the transcranial magnetic stimulation coil in the target brain area based on the registered brain tissue conductivity parameters, and dynamically correct the stimulation target coordinates of the virtual coil; The stimulation domain visualization module is used to dynamically display the position and orientation of the virtual coil corresponding to the transcranial magnetic stimulation coil on the three-dimensional brain model based on the completed coordinate system alignment results. It also synchronously updates the brain slice view based on the corrected target coordinates and highlights the boundaries of the brain area actually stimulated.

9. The optical navigation-based transcranial magnetic stimulation high-precision positioning device according to claim 8, wherein the electric field remapping module further comprises: Magnetic potential field calculation module, used to calculate the spatial magnetic vector potential distribution through the magnetic vector potential calculation formula; Conductivity building block, used to construct a hierarchical model of brain tissue conductivity; The electric field solving module is used to calculate the electric field strength using the coil electric field calculation formula; The target dynamic correction module is used to locate the electric field peak coordinates and generate an offset vector by comparing with the original target point.

10. An electronic device, characterized in that: A method for implementing high-precision transcranial magnetic stimulation positioning based on optical navigation as described in any one of claims 1 to 7, comprising: Medical imaging scanning equipment for generating raw data of a patient's three-dimensional brain model and providing coordinates of reference points in an imaging coordinate system; Optical positioning tracking equipment, used to collect the physical coordinate system coordinates of the reference points in real time and track the spatial position of the transcranial magnetic stimulation coil; Transcranial magnetic stimulation coils for non-invasive neuromodulation and dynamic mapping of driving virtual coils in 3D brain models; A processor for performing all computationally intensive tasks to implement a high-precision transcranial magnetic stimulation positioning method based on optical navigation; Memory is used to store processor executable instructions and static storage data.

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