Positioning system and method for transcranial ultrasound neuromodulation

Abstract

The present application relates to the field of medical devices, and discloses a positioning system and method for transcranial ultrasonic neuromodulation, the positioning system comprising: positioning glasses, including a frame and a plurality of fixing piles, on which magnetic resonance positioning marker balls or optical positioning marker balls can be replaceably mounted; and a positioning frame; wherein the magnetic resonance positioning marker balls are used to obtain image space coordinates during magnetic resonance scanning, and are replaced by optical positioning marker balls after the scanning is completed to obtain physical space coordinates during optical navigation; a registration relationship is established using image space coordinates and physical space coordinates, and by adjusting the positions and angles of the rectangular coordinate frame and the spherical coordinate frame, the focus of the ultrasonic transducer on the transducer fixture is aligned with the ultrasonic target position determined in the magnetic resonance image. The present invention provides a transcranial ultrasonic neuromodulation positioning solution that is easy to operate, has accurate positioning, and is suitable for repeated treatment, which reduces medical costs and improves patient experience.

Description

Technical Field

[0001] The present application relates to the field of medical devices, and in particular to a precise positioning technology for transcranial ultrasonic neuromodulation. Background Art

[0002] Ultrasound is a sound wave with a frequency range of more than 20,000 Hz. It can transmit mechanical energy of vibration and can therefore be used as an energy carrier to enter human tissues and achieve non-invasive intervention in human tissues. Transcranial ultrasound stimulation uses focused ultrasound to stimulate specific target areas of the brain, causing changes in neural activity. It is an innovative non-invasive neuromodulation technology. This technology is known for its high spatial resolution and deep penetration, and is compatible with other technologies such as magnetic resonance imaging and transcranial magnetic stimulation, showing a wide range of application potential.

[0003] In the practical application of transcranial ultrasound stimulation, it is crucial to accurately locate the ultrasound focus to the target area to ensure the spatial accuracy of treatment. Existing stereotactic techniques for transcranial ultrasound neuromodulation are mainly divided into three categories: optical navigation, magnetic resonance guidance, and stereotactic framework. These technologies are similar in the basic process of target planning, but there are significant differences in the image space and physical space registration methods.

[0004] Optical navigation positioning usually uses two methods: surface registration and point registration. In surface registration, the point cloud of the scalp surface is first extracted from the magnetic resonance image, and then an optical positioning probe is used to slide on the surface of the patient's head. The point cloud trajectory formed is recorded by an infrared optical navigation device, and these trajectories are registered with the surface in the magnetic resonance image to obtain a coordinate transformation relationship. The point registration method requires attaching visible markers to the head before the magnetic resonance scan, or marking several anatomical marker points on the magnetic resonance image, and locating these points under optical navigation to obtain the corresponding coordinate transformation relationship.

[0005] MRI-guided registration requires the patient to remain in the MRI device during treatment in order to register the intraoperative images with the preoperative images and obtain the coordinates of the target in physical space.

[0006] There are many types of stereotactic frames, such as the Spiegel-Wycis frame, the CRW frame, and the Leksell frame. Take the Leksell frame as an example, which consists of a rectangular coordinate frame and a spherical coordinate frame. When in use, the rectangular coordinate frame is first fixed to the skull after local anesthesia of the patient's scalp. The patient wears the frame for an MRI scan, and the frame can be seen in the image, and the coordinates of the target under the frame can be obtained. Subsequently, the spherical coordinate frame is installed on the rectangular coordinate frame and adjusted so that the center of the sphere of the spherical coordinate frame is aligned with the target. By adjusting the spherical coordinate frame, ensure that the treatment equipment on the frame (such as a puncture needle or ultrasonic transducer) can be accurately positioned at the target at an appropriate angle.

[0007] However, these technologies still have some problems. For example, optical navigation technology requires alignment during each positioning, which is cumbersome to operate. Magnetic resonance guided technology requires the patient to lie in the magnetic resonance equipment during each treatment, and the use of magnetic resonance requires medical resources and is very costly. The stereotactic positioning frame requires the positioning frame to be fixed on the patient's skull, and the frame must be worn during magnetic resonance scanning and treatment. The fixation of the frame to the skull is invasive, which may cause discomfort to the patient and increase the risk of infection, etc.

[0008] Therefore, there is an urgent need for a new positioning scheme that is easy to operate, precise in positioning, and suitable for repeated treatment, so as to improve the clinical application efficiency and therapeutic effect of transcranial ultrasound stimulation. Summary of the invention

[0009] The purpose of the present application is to provide a positioning system and method for transcranial ultrasonic neuromodulation to solve the problems raised in the above-mentioned background technology.

[0010] The present application discloses a positioning system for transcranial ultrasonic neuromodulation, the system comprising:

[0011] Positioning glasses, comprising a frame and a plurality of fixing piles fixed on the frame for detachably mounting positioning marker balls, wherein the fixing piles are replaceably mounted with magnetic resonance positioning marker balls or optical positioning marker balls;

[0012] A positioning frame, including an adjustable head support and a chin support, for fixing the patient's head and ensuring that the position of the patient's head remains unchanged during multiple treatments; the positioning frame also includes an adjustable and graduated positioning device for adjusting the position and angle of the ultrasonic transducer;

[0013] Among them, the magnetic resonance positioning marker ball is used to obtain image space coordinates during magnetic resonance scanning, and is replaced by the optical positioning marker ball after the scanning is completed to obtain physical space coordinates during optical navigation; a registration relationship is established using the image space coordinates and the physical space coordinates, and the focus of the ultrasonic transducer is aligned with the ultrasonic target position determined in the magnetic resonance image by adjusting the adjustable and scaled positioning device on the positioning frame; the scale on the positioning device is recorded during the first positioning, and in subsequent treatments, the positioning device is adjusted to the same scale, and accurate and repeated positioning of the focal point of the ultrasonic transducer can be achieved without re-alignment.

[0014] In a preferred example, the positioning frame includes a head frame for fixing the patient's head, a rectangular coordinate frame that is adjustable along three coordinate axes and has scales, a spherical coordinate frame connected to the rectangular coordinate frame and having an angle scale, and a transducer fixing device installed on the spherical coordinate frame for fixing the ultrasonic transducer, wherein the rectangular coordinate frame and the spherical coordinate frame are adjusted and recorded to specific scale positions during the first treatment so that they can be adjusted to the same scale in subsequent treatments.

[0015] In a preferred embodiment, the registration device is selected from the following group: positioning glasses, masks, and eye masks.

[0016] In a preferred embodiment, the rectangular coordinate frame and the spherical coordinate frame are adjusted and recorded to specific scale positions during the first treatment so that they can be adjusted to the same scale during subsequent treatments, thereby achieving accurate and repeated positioning of the focal point of the ultrasound transducer without having to re-perform the alignment step.

[0017] In a preferred example, the magnetic resonance positioning marker ball comprises a spherical cavity filled with a magnetic resonance contrast agent, and the surface of the optical positioning marker ball is provided with a reflective mark for reflecting infrared light of the optical navigation system.

[0018] In a preferred embodiment, the inner diameter of the spherical cavity of the magnetic resonance positioning marker ball is the same as the outer diameter of the spherical surface of the optical positioning marker ball, so that the center positions of the two positioning marker balls coincide when they are inserted into the same fixing pile.

[0019] In a preferred embodiment, the process of establishing a registration relationship using image space coordinates and physical space coordinates includes:

[0020] During magnetic resonance scanning, at least four magnetic resonance positioning marker balls (n≥4) are installed on the registration device, such as the positioning marker ball fixing pile of the positioning glasses, and the coordinates x of each magnetic resonance positioning marker ball in the image space are obtained. i =[x 1i , x 2i , x 3i ] T , where i = 1, 2, 3, ..., n;

[0021] During optical navigation, the same number of optical positioning marker balls are installed on the same positioning marker ball fixing pile, and the coordinate y of each optical positioning marker ball in the physical space is obtained. i =[y 1i ,y 2i ,y 3i ] T ;

[0022] Calculate the center of mass coordinates of the magnetic resonance positioning marker ball in the image space and the center of mass coordinates of the optical positioning marker ball in physical space

[0023] Calculate the displacement vector of the magnetic resonance localization marker ball relative to the center of mass of the image space and the displacement vector of the optical positioning marker ball relative to the center of mass in physical space

[0024] Calculate the covariance matrix of image space coordinates and physical space coordinates Perform singular value decomposition of the covariance matrix H = UΛV T , and get the rotation matrix R = VU T and displacement vector Establish the registration relationship between image space and physical space.

[0025] In a preferred example, the rectangular coordinate frame includes: an X-axis slide, a Y-axis slide, a lifting rod, a locking device and a bushing; the spherical coordinate frame includes: an arc scale and a rotational locator; wherein the arc scale and the rotational locator are used to adjust the angle of the ultrasonic transducer, the X-axis slide, the Y-axis slide and the lifting rod respectively provide translational freedom along the X-axis, Y-axis and Z-axis, the locking device is used to lock the height of the lifting rod, and the bushing is used to connect the lifting rod and the seat.

[0026] In a preferred example, the positioning frame is installed on the seat through a lifting rod, a locking device and a sleeve. The lifting rod controls the positioning frame to translate along the Z-axis direction. The lifting rod is provided with a scale, and the relative position of the lifting rod and the sleeve can be fixed by the locking device.

[0027] In a preferred example, the lifting rod is provided with an X-axis slide and a Y-axis slide for controlling the translation of the positioning frame along the X-axis and Y-axis directions. The X-axis slide and the Y-axis slide are both provided with scales with a minimum division of 1 mm.

[0028] In a preferred example, a rotary locator is provided on the X-axis slide, and the rotary locator is meshedly connected to the arc scale through a hirth disk and can rotate relative to each other with a positioning accuracy of 1°. The rotary locator is provided with an angle scale with a minimum division of 1°.

[0029] In a preferred example, the arc-shaped scale is fixed to the ultrasonic transducer holder by means of a set screw, the ultrasonic transducer holder can slide along the arc-shaped scale to adjust the ultrasonic incident angle, and the minimum graduation of the arc-shaped scale is 0.5°.

[0030] In a preferred example, the ultrasonic transducer holder is used to fix the ultrasonic transducer and can adjust the radial position of the ultrasonic transducer along the arc scale to accommodate targets at different depths. In addition, a marker for optical navigation is installed on the ultrasonic transducer to obtain its position coordinates.

[0031] In a preferred example, the positioning frame further includes an adjustable head rest and a chin rest, wherein: the head rest is used to prevent the head from moving relative to the seat, and the height can be adjusted to adapt to the head shape and height of different patients, and the back of the head rest has a scale for keeping the position of the patient's head unchanged during subsequent treatment; the chin rest is fixed to the head rest by an adjustable strap, and the strap has a buckle and a slot with a scale for adjusting the tightness to ensure that the position of the patient's head is fixed in the subsequent treatment in the same way as during the initial treatment.

[0032] In a preferred embodiment, the rigid part of the registration device is made of a material that is invisible under magnetic resonance, and the material is selected from at least one of polylactic acid, polyetheretherketone, polycarbonate and thermoplastic rubber.

[0033] The present application also provides a positioning method for transcranial ultrasonic neuromodulation, using any of the aforementioned positioning systems, the positioning method comprising the following steps:

[0034] S1: The patient wears the registration device, for example, positioning glasses, and performs magnetic resonance scanning to obtain the three-dimensional coordinates of the magnetic resonance positioning marker ball in the image space;

[0035] S2: replacing the magnetic resonance positioning marker ball with the optical positioning marker ball, and using an optical navigation system to obtain the three-dimensional coordinates of the optical positioning marker ball in the physical space;

[0036] S3: Based on the three-dimensional coordinates of the magnetic resonance positioning marker ball in the image space and the three-dimensional coordinates of the optical positioning marker ball in the physical space, a coordinate transformation relationship between the image space and the physical space is established through a rigid transformation algorithm;

[0037] S4: determining the three-dimensional coordinates of the ultrasound target in the image space according to a preset transcranial ultrasound stimulation scheme, and then converting the coordinates of the target into the physical space by using the coordinate conversion relationship between the image space and the physical space;

[0038] S5: adjusting the positioning frame, the ultrasonic transducer holder, the arc ruler and the rotary positioner so that the focus of the ultrasonic transducer is aligned with the converted target coordinates, and recording the scale readings of each axis of the positioning frame at this time, so as to quickly reproduce the precise positioning later;

[0039] S6: Start transcranial ultrasound stimulation therapy;

[0040] S7: During subsequent treatment, it is only necessary to quickly adjust the positioning frame, ultrasonic transducer holder, arc ruler and rotation positioner to the corresponding scale readings recorded in step S5 during the first treatment, and then perform the intervention treatment of step S6 without repeating steps S1 to S5.

[0041] In a preferred example, the step S5 further comprises:

[0042] S51: Determine the coordinates of the ultrasonic transducer using an optical navigation system;

[0043] S52: by adjusting the X-axis slide, Y-axis slide and lifting rod of the positioning frame, the center of the arc scale of the positioning frame is located at the target point, ensuring that the incident direction of the ultrasonic transducer is aligned with the target point, and recording the scales of the X-axis slide, Y-axis slide and lifting rod after the adjustment is completed;

[0044] S53: Adjust the ultrasonic transducer holder, arc ruler and rotary positioner again, so that the ultrasonic transducer focuses the ultrasound to the target point according to the preset incident path. After the adjustment is completed, record the scales of the ultrasonic transducer holder, arc ruler and rotary positioner.

[0045] The embodiments of the present application have the following technical features and effects:

[0046] Improve positioning accuracy: By combining the use of magnetic resonance positioning marker balls and optical positioning marker balls, high-precision registration between image space and physical space is achieved. This registration ensures that the ultrasound focus can be accurately aligned with the target, thereby enhancing the treatment effect and reducing the impact of non-target areas.

[0047] Simplified operation process: The system design reduces the need for repeated MRI scans and optical navigation in each treatment. Once the positioning parameters in the initial treatment are set and recorded, subsequent treatments only require adjusting the positioning frame to the preset scale without re-performing complex alignment steps, thereby simplifying the operation process and shortening treatment preparation time.

[0048] Improved cost efficiency: The design of this application reduces the reuse of optical navigation and magnetic resonance equipment, significantly reducing treatment costs. After performing magnetic resonance and optical navigation once in the first treatment, the key positioning scales are recorded. Subsequent treatments only require adjusting the positioning framework according to these scales, without the need to use magnetic resonance or optical navigation again, thereby effectively reducing the frequency of use of high-cost medical equipment, simplifying the treatment process, and improving the economic benefits and operational efficiency of transcranial ultrasound neuromodulation.

[0049] Improved patient comfort: The positioning system includes an ergonomically designed headrest and chinrest with soft pads that conform to the patient's head and prevent displacement during treatment, increasing patient comfort.

[0050] Consistency and reliability of repeated treatments: The system design allows the same positioning parameters to be reused in consecutive treatment cycles. By adjusting the positioning frame to the recorded scale, consistency and reliability of treatment are ensured, especially for patients who require multiple treatments.

[0051] Traceability and standardization of treatment: The system provides a method for the medical team to accurately track and reproduce the specific operations of each treatment by recording the specific scales of key positioning components, which is of great value for evaluating treatment effects and standardizing operations.

[0052] In conclusion, this system provides a precise, efficient, cost-effective, and patient-friendly solution for transcranial ultrasound neuromodulation therapy through its innovative design and technology integration.

[0053] A large number of technical features are recorded in the specification of this application, which are distributed in various technical solutions. If all possible combinations of technical features of this application (i.e., technical solutions) are to be listed, the specification will be too long. In order to avoid this problem, the various technical features disclosed in the above-mentioned invention content of this application, the various technical features disclosed in the various embodiments and examples below, and the various technical features disclosed in the accompanying drawings can be freely combined with each other to form various new technical solutions (these technical solutions are all deemed to have been recorded in this specification), unless the combination of such technical features is technically infeasible. For example, in one example, feature A+B+C is disclosed, and in another example, feature A+B+D+E is disclosed, and features C and D are equivalent technical means that play the same role. Technically, only one can be used, and it is impossible to use them at the same time. Feature E can be combined with feature C technically. Then, the solution of A+B+C+D should not be deemed to have been recorded because it is technically infeasible, and the solution of A+B+C+E should be deemed to have been recorded. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a schematic diagram of the structure of positioning glasses for a positioning system for transcranial ultrasonic neuromodulation according to the first embodiment of the present application.

[0055] Figure 2 and Figure 3 It is a schematic diagram of the positioning framework structure of the positioning system for transcranial ultrasonic neuromodulation according to the first embodiment of the present application.

[0056] Figure 4 It is a flow chart of a method for using a positioning system for transcranial ultrasonic neuromodulation according to the first embodiment of the present application.

[0057] Figure 5It is a flow chart of a positioning method for transcranial ultrasonic neuromodulation according to the second embodiment of the present application.

[0058] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0059] 101: Frames

[0060] 102: Positioning mark ball fixed pile

[0061] 103: Positioning Marker Ball

[0062] 201: Ultrasonic transducer

[0063] 202: Ultrasonic transducer holder

[0064] 203: Arc Ruler

[0065] 204: Rotary Positioner

[0066] 205: Ball screw X-axis slide

[0067] 206: Ball screw Y-axis slide

[0068] 207: Lifting rod

[0069] 208: Locking device

[0070] 209: Bushing

[0071] 210: Seat

[0072] 211: Headrest

[0073] 212: Mandibular support DETAILED DESCRIPTION

[0074] In the following description, many technical details are provided to help readers better understand the present application. However, those skilled in the art can understand that the technical solution claimed in the present application can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0075] Description of some concepts:

[0076] Transcranial ultrasound stimulation is a technology that uses low-intensity, low-frequency focused ultrasound to stimulate specific nerves or functional areas inside the brain in order to regulate brain nerve activity. Compared with other neuromodulation technologies, it has the advantages of being non-invasive, having a large stimulation depth, and having a high spatial resolution.

[0077] An ultrasonic transducer is a device that converts electrical energy into sound energy. It is usually made of piezoelectric ceramics or other magnetostrictive materials. An ultrasonic transducer can be used to emit ultrasonic waves, allowing them to penetrate the skull and focus on a specific area, thereby achieving transcranial ultrasonic stimulation.

[0078] Registration, in the context of transcranial ultrasound stimulation, is the process of converting the coordinates of specific anatomical structures of the patient's brain in the magnetic resonance image to the coordinates of the patient's brain in physical space.

[0079] Positioning, in the scenario of transcranial ultrasound stimulation, positioning is the process of accurately placing the ultrasound transducer at a specific location so that the ultrasound waves can be focused on the target point, thereby achieving transcranial ultrasound neuromodulation.

[0080] Target area: The brain area to which transcranial ultrasound stimulation is intended, usually a brain structure associated with a specific disease or function, such as the subthalamic nucleus for Parkinson's disease, the dorsolateral thalamus for tremor, and the dorsolateral prefrontal lobe for depression.

[0081] Cartesian Frame: refers to the part of the positioning frame that is adjustable along the X, Y, and Z axes and has scales to allow precise control of position.

[0082] Spherical coordinate frame: refers to the extended part of the rectangular coordinate frame, which is used to adjust the position and angle of the ultrasonic transducer in the spherical coordinate system.

[0083] Rigid transformation: refers to the mathematical transformation used to transform a set of points from image space to physical space, including rotation and translation, aiming to keep the relative positions and distances between points unchanged.

[0084] The following is a brief description of some of the innovative features of this application:

[0085] In general, this application uses optical navigation for the first time to locate transcranial ultrasound stimulation and saves the scale information of each structure of the positioning frame. When performing transcranial ultrasound stimulation on the same patient again or multiple times subsequently, it is only necessary to adjust the various structures of the positioning frame to the scales of each structure recorded during the first transcranial ultrasound stimulation. This method of positioning transcranial ultrasound stimulation can be completed without using optical navigation again.

[0086] Advantages of this approach include:

[0087] Time efficiency: It avoids the need for registration and navigation positioning under the optical navigation system for each treatment, thereby reducing the patient's waiting time and treatment preparation time.

[0088] Cost-effectiveness: Reduces the need for optical navigation systems, lowering the overall cost of treatment.

[0089] Patient Comfort: Reduces the discomfort experienced by patients due to longer alignment and navigation times, as the frequent need for alignment and navigation under optical navigation systems is reduced.

[0090] Easy to operate: Doctors can quickly reproduce the positioning of the initial treatment during follow-up treatment, simplifying the treatment process.

[0091] Through this method, the present application greatly improves the operability and convenience of transcranial ultrasound treatment, and also makes the treatment process more patient-friendly.

[0092] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0093] The first embodiment of the present application relates to a positioning system for transcranial ultrasound neuromodulation, the structure of which is as follows: Figure 1 , Figure 2 and Figure 3 As shown, including:

[0094] Positioning glasses, comprising a frame and a plurality of fixing piles 102 fixed on the frame for detachably mounting positioning marker balls 103, wherein magnetic resonance positioning marker balls (hereinafter referred to as "magnetic resonance positioning marker balls 103") or optical positioning marker balls (hereinafter referred to as "optical positioning marker balls 103") are replaceably mounted on the fixing piles 102;

[0095] A positioning frame, including an adjustable head support 211 and a chin support 212, for fixing the patient's head and ensuring that the position of the patient's head remains unchanged during multiple treatments; the positioning frame also includes an adjustable and graduated positioning device for adjusting the position and angle of the ultrasonic transducer;

[0096] Among them, the magnetic resonance positioning marker ball 103 is used to obtain image space coordinates during magnetic resonance scanning, and is replaced by the optical positioning marker ball 103 after the scanning is completed to obtain physical space coordinates during optical navigation; a registration relationship is established using the image space coordinates and the physical space coordinates, and the focus of the ultrasonic transducer is aligned with the ultrasonic target position determined in the magnetic resonance image by adjusting the adjustable and scaled positioning device on the positioning frame; the scale on the positioning device is recorded during the first positioning, and in subsequent treatments, the positioning device is adjusted to the same scale, and accurate and repeated positioning of the focal point of the ultrasonic transducer can be achieved without re-alignment.

[0097] It should be pointed out that according to the positioning system for transcranial ultrasonic neuromodulation of this embodiment, the rectangular coordinate frame and the spherical coordinate frame are adjusted and recorded to specific scale positions in the first treatment so that they can be adjusted to the same scale in subsequent treatments, thereby achieving accurate and repeated positioning of the focal point of the ultrasonic transducer 201 without the need to re-perform the alignment step.

[0098] The positioning glasses of this embodiment are further explained below.

[0099] Optionally, the frame 101 of the positioning glasses is made of a material that is invisible under magnetic resonance, and the material is selected from at least one of polylactic acid, polyetheretherketone, polycarbonate and thermoplastic rubber.

[0100] Optionally, the magnetic resonance positioning marker ball 103 includes a spherical cavity filled with a magnetic resonance contrast agent, and the surface of the optical positioning marker ball 103 is provided with a reflective mark for reflecting infrared light of an optical navigation system.

[0101] Optionally, the inner diameter of the spherical cavity of the magnetic resonance positioning marker ball 103 is the same as the outer diameter of the spherical surface of the optical positioning marker ball 103, so as to ensure that the shape of the magnetic resonance contrast agent is the same as that of the optical marker ball, avoid errors during alignment, and when the two positioning marker balls 103 are inserted into the same fixed post 102, their center positions coincide.

[0102] Optionally, the frame 101 is designed as a rigid structure and is equipped with a set of interchangeable positioning marker balls 103, wherein the registration process includes:

[0103] The patient tries on the frames 101 and chooses a pair that is firm and comfortable;

[0104] At least four magnetic resonance positioning marker balls 103 are mounted on the fixing posts 102 of the mirror frame 101, and magnetic resonance scanning is performed to obtain the coordinates of each magnetic resonance positioning marker ball 103 in the image space;

[0105] The magnetic resonance positioning marker beads 103 are replaced with optical positioning marker beads 103, and the coordinates of each optical positioning marker bead 103 in the physical space are obtained under the optical navigation system;

[0106] According to the coordinates of each magnetic resonance positioning marker ball 103 in the image space and the coordinates of each optical positioning marker ball 103 in the physical space, the precise coordinate transformation relationship from the image space to the physical space is established by calculating the covariance matrix and performing singular value decomposition, including the determination of the rotation matrix and the displacement vector, to achieve alignment.

[0107] More specifically, the process of establishing a registration relationship using image space coordinates and physical space coordinates includes:

[0108] During magnetic resonance scanning, at least four magnetic resonance positioning marker balls 103 (n≥4) are installed on the positioning marker ball 103 fixing post 102 of the positioning glasses, and the coordinate x of each magnetic resonance positioning marker ball 103 in the image space is obtained. i =[x 1i , x 2i , x 3i ] T , where i = 1, 2, 3, ..., n;

[0109] During optical navigation, the same number of optical positioning marker balls 103 are installed on the same positioning marker ball 103 fixing pile 102, and the coordinate y of each optical positioning marker ball 103 in the physical space is obtained. i =[y 1i ,y 2i ,y 3i ] T ;

[0110] Calculate the centroid coordinates of the magnetic resonance positioning marker ball 103 in the image space respectively and the center of mass coordinates of the optical positioning marker ball 103 in physical space

[0111] Calculate the displacement vector of the magnetic resonance positioning marker ball 103 relative to the center of mass of the image space and the displacement vector of the optical positioning marker ball 103 relative to the center of mass of the physical space

[0112] Calculate the covariance matrix of image space coordinates and physical space coordinates Perform singular value decomposition of the covariance matrix H = UΛV T , and get the rotation matrix R = VU T and displacement vector Establish the registration relationship between image space and physical space.

[0113] The positioning glasses of this embodiment have the following characteristics and functions:

[0114] 1) Easy to wear:

[0115] The positioning glasses are designed similarly to ordinary glasses and are available in a variety of sizes to accommodate patients with different head shapes and head circumferences.

[0116] Patients only need to wear the positioning glasses like ordinary glasses. It is easy to operate, comfortable to wear, and will not cause any additional discomfort.

[0117] 2) Magnetic resonance imaging:

[0118] The positioning glasses are equipped with special small balls filled with contrast agents that are sensitive to MRI.

[0119] When patients wear positioning glasses for MRI scans, these small balls can be clearly visualized on the MRI images.

[0120] By identifying the positions of these balls on the image, their coordinates in the magnetic resonance image coordinate system (ie, image space) can be obtained.

[0121] 3) Optical navigation positioning:

[0122] For optical navigation, the small ball on the positioning glasses can be replaced with an optical ball covered with a reflective coating.

[0123] When performing optical navigation, these optical balls can reflect infrared rays emitted by the optical positioning system.

[0124] By detecting the position of the reflected light, the optical navigation system can calculate the coordinates of the optical ball in the real-world coordinate system (i.e., physical space).

[0125] 4) Registration between image space and physical space:

[0126] Since the positions of the magnetic resonance sphere and the optical sphere on the positioning glasses are fixed, there is a fixed geometric relationship between them.

[0127] The image space coordinates of the magnetic resonance sphere are obtained through magnetic resonance imaging, and the physical space coordinates of the optical sphere are obtained through optical navigation.

[0128] Using these two sets of corresponding coordinates, the coordinate transformation relationship from image space to physical space can be calculated (usually expressed as a transformation matrix).

[0129] With this conversion relationship, any point on the image (such as the target area) can be mapped to the actual position of the patient's head, achieving precise positioning under image guidance.

[0130] In summary, the positioning glasses cleverly combine the two positioning methods of magnetic resonance imaging and optical navigation. Through the replaceable magnetic resonance balls and optical balls, a corresponding relationship is established in the two spaces, thereby realizing the registration of the image space and the physical space. Compared with the traditional method, it is simple to operate, comfortable to wear, avoids dependence on anatomical landmarks, reduces the error of landmark selection, and has obvious advantages. This innovation is one of the cores of the method of this application.

[0131] It should be noted that in other embodiments of the present application, the above-mentioned positioning glasses can be replaced by other devices, such as masks or eye masks. These alternative devices should include a rigid component for fixing to the patient's head (for example, the frame 101 of the positioning glasses), and be provided with a plurality of fixing piles for detachably mounting the positioning marker balls. On these fixing piles, the magnetic resonance positioning marker balls or the optical positioning marker balls can be replaced and installed. Therefore, the positioning glasses, masks or eye masks, etc. can be collectively referred to as "alignment devices".

[0132] In addition, the number and position of the fixed stakes can be adjusted according to specific needs and are not limited to the configuration of the attached figure. The key is to ensure that the optical navigation camera can capture at least four balls at the same time, and the balls should not be collinear and light must not be blocked to ensure navigation accuracy.

[0133] The positioning framework of this embodiment is further explained below.

[0134] Optionally, the rectangular coordinate frame includes: an X-axis slide, a Y-axis slide, a lifting rod 207, a locking device 208 and a sleeve 209; the spherical coordinate frame includes: an arc scale 203 and a rotation positioner 204; wherein the arc scale 203 and the rotation positioner 204 are used to adjust the angle of the ultrasonic transducer 201, the X-axis slide, the Y-axis slide and the lifting rod 207 respectively provide translational freedom along the X-axis, Y-axis and Z-axis, the locking device 208 is used to lock the position of the positioning frame, and the sleeve 209 is used to connect the various components.

[0135] Optionally, the positioning frame is installed on the seat 210 through a lifting rod 207, a locking device 208 and a sleeve 209. The lifting rod 207 controls the positioning frame to translate along the Z-axis direction. The lifting rod 207 is provided with a scale, and the relative position of the lifting rod 207 and the sleeve 209 can be fixed by the locking device 208.

[0136] Optionally, the lifting rod 207 is provided with an X-axis slide and a Y-axis slide for controlling the positioning frame to translate along the X-axis and Y-axis directions. The X-axis slide and the Y-axis slide are both provided with scales, and the minimum division is 1 mm.

[0137] Optionally, a rotary locator 204 is provided on the X-axis slide, and the rotary locator 204 is meshedly connected with the arc scale 203 through a hirth disk and can rotate relatively with a positioning accuracy of 1°. The rotary locator 204 is provided with an angle scale with a minimum division of 1°.

[0138] Optionally, the arc-shaped scale 203 is fixed to the ultrasonic transducer holder 202 by means of a set screw, and the ultrasonic transducer holder 202 can slide along the arc-shaped scale 203 to adjust the ultrasonic incident angle, and the minimum division of the arc-shaped scale 203 is 0.5°.

[0139] Optionally, the ultrasonic transducer holder 202 is used to fix the ultrasonic transducer 201, and can adjust the radial position of the ultrasonic transducer 201 along the arc scale 203 to accommodate targets at different depths. In addition, a marker for optical navigation is installed on the ultrasonic transducer 201 to obtain its position coordinates.

[0140] Optionally, the positioning frame further includes an adjustable head support 211 and a chin support 212, wherein: the head support 211 is used to prevent the head from displacing relative to the seat 210, and the height can be adjusted to adapt to the head shape and height of different patients, and the back of the head support 211 has a scale for keeping the position of the patient's head unchanged during subsequent treatment; the chin support 212 is fixed to the head support 211 by an adjustable strap, and the strap has a buckle and a slot with a scale for adjusting the tightness to ensure that the position of the patient's head is fixed in the subsequent treatment in the same way as during the initial treatment.

[0141] The positioning framework of this embodiment has the following characteristics and functions:

[0142] 1) Combination of rectangular coordinates and spherical coordinate systems:

[0143] The positioning frame uses a combination of rectangular coordinates (X, Y, Z axes) and spherical coordinates (angle, radial distance).

[0144] The rectangular coordinate system can realize the translation movement of the ultrasonic transducer 201 in three orthogonal directions to adjust its position.

[0145] The spherical coordinate system can realize the rotational motion of the ultrasonic transducer 201 in two angular dimensions, adjust its orientation, and move it in the radial direction.

[0146] This combination of coordinate systems can provide 6 degrees of freedom (3 translations + 2 rotations + 1 radial movement), enabling all-round adjustment of the position and orientation of the ultrasonic transducer 201 .

[0147] 2) First positioning and recording of scale:

[0148] During the first treatment, the ultrasound transducer 201 is precisely positioned to the target area using the positioning glasses and optical navigation system described above.

[0149] After reaching the ideal position, record the scale readings on each coordinate axis and rotation axis of the positioning frame at this time.

[0150] These scale readings reflect the relative position and orientation of the ultrasound transducer 201 with respect to the patient's head.

[0151] 3) Rapid positioning of follow-up treatment:

[0152] During the second and subsequent treatments, there is no need to reuse the positioning glasses and the optical navigation system.

[0153] Instead, the various coordinate axes and rotation axes of the positioning frame are adjusted directly based on the scale readings recorded for the first time, so that they reach the same position and orientation as during the first treatment.

[0154] Since the position of the patient's head is fixed by the head support 211 and the chin support 212 and is basically the same as that during the first treatment, the ultrasonic transducer 201 will also automatically align with the target area to achieve fast and accurate positioning.

[0155] 4) Advantages and innovations:

[0156] Traditional positioning methods usually require re-image guidance and re-registration during each treatment, which is time-consuming and labor-intensive.

[0157] In this example, the scale record of the positioning frame is used to "solidify" the result of the first precise positioning, which can be directly reproduced in subsequent treatments without repeating the navigation and alignment process.

[0158] This method greatly simplifies the operational process of subsequent treatment, shortens preparation time and improves treatment efficiency.

[0159] At the same time, due to the high precision of scale recording and reproduction, the accuracy of positioning is also guaranteed, ensuring the consistency and repeatability of treatment.

[0160] In summary, the design and use of the positioning frame is another highlight of the method of the present application. It cleverly utilizes the combination of coordinate systems to provide sufficient degrees of freedom, and achieves the solidification and reproduction of precise positioning results through scale recording, so that subsequent treatment can quickly and accurately position the ultrasonic transducer 201 without relying on image guidance. This is a major improvement and optimization of traditional methods, with significant innovation and practical value.

[0161] Working principle:

[0162] In this embodiment, the positioning system of transcranial ultrasound neuromodulation mainly optimizes the treatment accuracy and operation efficiency of transcranial ultrasound stimulation by combining magnetic resonance positioning technology with an optical navigation system. The following is an overview of the working principle of the system:

[0163] 1) Use of positioning glasses: The patient wears special positioning glasses equipped with interchangeable positioning marker balls 103, including magnetic resonance positioning marker balls 103 and optical positioning marker balls 103. During the magnetic resonance scanning phase, positioning marker balls 103 filled with magnetic resonance contrast agents are used to obtain accurate image space coordinates. After scanning, these magnetic resonance positioning marker balls 103 are replaced with optical positioning marker balls 103 for use in the optical navigation phase.

[0164] 2) Combination of magnetic resonance scanning and optical navigation: During the magnetic resonance scanning stage, the precise position of the target is obtained by the coordinates of the positioning marker ball 103 in the image space. Subsequently, during the optical navigation stage, the coordinates in the physical space are obtained by the optical positioning marker ball 103 on the same positioning glasses, thereby achieving precise alignment between the image space and the physical space.

[0165] 3) Application of positioning frame: The positioning frame includes multiple adjustable parts, such as a rectangular coordinate frame, a spherical coordinate frame and an ultrasonic transducer 201 fixing device. These parts are used in combination to accurately adjust the position and angle of the ultrasonic transducer 201 to ensure that the ultrasonic wave can be accurately focused on the target.

[0166] 4) Scale recording and reuse: In the first treatment, once the ultrasonic transducer 201 is positioned to the ideal position through optical navigation, the scale of the positioning frame will be recorded. In subsequent treatments, the positioning frame can be adjusted according to these recorded scales to achieve fast and accurate positioning without the need to re-perform magnetic resonance scanning or optical navigation.

[0167] The positioning system for transcranial ultrasonic neuromodulation of this embodiment simplifies the preparation and execution process of transcranial ultrasound treatment, reduces the frequent use of optical navigation systems, reduces treatment costs, improves the time efficiency of treatment, and also reduces the burden on patients.

[0168] In general, this system effectively solves the problems of complex operation, high cost, and long time consumption in traditional treatments through innovative combination of technologies, making transcranial ultrasound neuromodulation therapy more precise and efficient.

[0169] In this embodiment, the positioning system for transcranial ultrasound neuromodulation has the following main technical effects:

[0170] 1) Improving positioning accuracy: High-precision registration between image space and physical space is achieved by combining the use of magnetic resonance positioning marker beads 103 and optical positioning marker beads 103. This registration ensures that the ultrasound focus can be accurately aligned with the target, thereby enhancing the treatment effect and reducing the impact of non-target areas.

[0171] 2) Simplified operation process: The system design reduces the need to repeat optical navigation in each treatment. Once the positioning parameters in the initial treatment are set and recorded, subsequent treatments only require adjusting the positioning frame to the preset scale without re-performing complex alignment steps, thereby simplifying the operation process and shortening treatment preparation time.

[0172] 3) Improved cost efficiency: Reducing reliance on optical navigation reduces treatment costs. By utilizing an optical navigation system and pre-recorded positioning scales, the frequency of using high-cost medical equipment can be effectively reduced.

[0173] 4) Improving patient comfort: The positioning system includes an ergonomically designed head rest 211 and a chin rest 212. These accessories are padded to fit the patient's head and prevent displacement during treatment, thereby increasing the patient's comfort.

[0174] 5) Consistency and reliability of repeated treatments: The system design allows the same positioning parameters to be reused in consecutive treatment cycles. By adjusting the positioning frame to the recorded scale, the consistency and reliability of treatment are ensured, especially for patients who require multiple treatments.

[0175] 6) Traceability and standardization of treatment: The system provides a method for the medical team to accurately track and reproduce the specific operations of each treatment by recording the specific scales of key positioning components, which is of great value for the evaluation of treatment effects and standardized operations.

[0176] In conclusion, this system provides a precise, efficient, cost-effective, and patient-friendly solution for transcranial ultrasound neuromodulation therapy through its innovative design and technology integration.

[0177] In order to better understand the technical solution of the present application, a specific example is provided below for illustration. The details listed in the example are mainly for ease of understanding and are not intended to limit the scope of protection of the present application.

[0178] In this example, the advantages of optical navigation and stereotactic framework are combined to make up for their shortcomings. Compared with several existing stereotactic technologies for transcranial ultrasound neuromodulation, the process is simpler and more efficient while ensuring accuracy, and can meet the needs of clinical transcranial ultrasound stimulation for course-based treatment. The so-called course-based treatment refers to the need to perform multiple repeated transcranial ultrasound stimulation on the patient over a period of time, and each stimulation must be accurately positioned to the same brain target. This method can avoid the complex operation of repeating optical navigation alignment during each treatment, thereby improving treatment efficiency and patient experience.

[0179] This example proposes a registration technology that simplifies the registration process and reduces the registration error. The registration methods of traditional optical navigation mainly include point registration and surface registration. For point registration, it is necessary to find the anatomical landmarks in the patient's magnetic resonance image and the anatomical landmarks on the surface of the patient's head one by one for registration. The operation is relatively cumbersome and errors will be generated in the selection process of the anatomical landmarks. For surface registration, it is necessary to use the optical navigation probe tool to pass over the patient's scalp surface and use the point cloud data to align with the magnetic resonance image, which requires a certain amount of calculation time. This example uses positioning glasses that are visible in both magnetic resonance and optical navigation. The patient wears the positioning glasses for magnetic resonance scanning, and then quickly completes the registration under optical navigation. It no longer relies on anatomical features for registration, which can not only greatly save the time required for registration, but also reduce the error of landmark registration.

[0180] In addition, this example proposes an ultrasonic transducer positioning technology, which simplifies the positioning process and saves navigation positioning time. Existing registration technology solutions all require magnetic resonance scanning before surgery, but the difference between them is that optical navigation technology requires registration each time it is positioned, and the operation is relatively cumbersome; while magnetic resonance guidance technology requires the patient to lie in the magnetic resonance device during each treatment, and the use of magnetic resonance requires medical resources and is very costly; the stereotactic positioning frame requires the positioning frame to be fixed on the patient's skull, and the frame must be worn during magnetic resonance scanning and treatment. The fixation of the frame to the skull is invasive, which may cause discomfort to the patient and increase the risk of infection. This example designs an adjustable headrest and mandibular support that can adapt to the patient's height and head shape, which can ensure that the patient's head position remains unchanged during multiple treatments; and an adjustable and scaled positioning frame is designed to keep the transducer position unchanged during multiple treatments. Therefore, the advantage of this example is that it only requires alignment like optical navigation technology when positioning each patient for the first time, and then records the scale on the positioning frame. No alignment is required in subsequent treatments, and the positioning frame can be directly used to accurately position according to the scale recorded during the first positioning. Since transcranial ultrasound neuromodulation often requires regular and multiple interventions, compared with traditional optical navigation technology, this example can greatly simplify the positioning process of the second and subsequent transcranial ultrasound stimulations, while eliminating the alignment step, ensuring positioning accuracy and saving a lot of time; compared with magnetic resonance guidance technology, this example does not need to use magnetic resonance equipment in every treatment, which increases the flexibility of treatment space and time; compared with the stereotactic positioning frame, this example is non-invasive, does not cause obvious discomfort, can reduce the risk of infection, and increase patients' willingness to receive treatment.

[0181] This example effectively solves the problem of how to quickly and accurately achieve registration of image space and physical space in transcranial ultrasound stimulation, ensure the precise positioning of the ultrasound transducer and target in physical space, and avoid multiple registrations during repeated treatments.

[0182] This example consists of two parts, the first part is the positioning glasses, and the second part is the positioning frame.

[0183] In the first part, this example proposes the use of easy-to-wear positioning glasses that can be developed in magnetic resonance and obtain spatial position information under optical navigation to achieve alignment between image space and physical space.

[0184] In the second part, this example proposes using a positioning frame with 6 degrees of freedom that combines a rectangular coordinate system with a spherical coordinate system to fix the ultrasonic transducer. After the ultrasonic transducer is positioned using optical navigation for the first time, the scale of the positioning frame is recorded. This means that optical navigation is no longer required for the second and subsequent treatments, thereby achieving rapid positioning.

[0185] As attached Figure 1 As shown, the frame 101 is made of a material that is safe for the human body and invisible under magnetic resonance (can be made by 3D printing or other molding methods). For example, the 3D printing material is a 3D printing material that meets medical standards and has biocompatibility, such as polylactic acid (PLA) and polyetheretherketone (PEEK). Other molding methods can refer to the materials used in eyeglass frames on the market, such as polycarbonate (PC) and thermoplastic rubber (TR). Optionally, the frame 101 has a variety of sizes to suit patients with different head circumferences.

[0186] The frame 101 has a fixing post for fixing a small ball used as a positioning mark, that is, a positioning mark ball fixing post 102. A positioning mark ball 103 filled with a magnetic resonance contrast agent can be inserted into the positioning mark ball fixing post 102 for imaging on magnetic resonance; an optical positioning mark ball 103 can also be inserted into the positioning mark ball fixing post 102 for the optical navigation system to locate and obtain the spatial position information of the glasses. After scanning the magnetic resonance and optical navigation positioning, the coordinates of the positioning mark ball fixing post 102 in the image space and the physical space can be obtained, and the coordinate conversion matrix of the two spaces can be calculated to complete the registration.

[0187] There are two types of positioning marker beads 103 installed on the frame 101. One is a positioning marker bead 103 filled with a magnetic resonance contrast agent, which can be developed in magnetic resonance; the other is an optical positioning marker bead 103, which provides the position information of the positioning marker bead 103 in optical navigation by reflecting infrared rays. The positioning marker bead 103 filled with a magnetic resonance contrast agent has an inner cavity filled with a magnetic resonance contrast agent, and the diameter of the inner cavity is the same as the diameter of the spherical outer surface of the optical positioning marker bead 103, so as to ensure that the shape of the magnetic resonance contrast agent is the same as that of the optical positioning marker bead, so as to avoid errors in registration. When scanning magnetic resonance, the positioning marker bead 103 filled with a magnetic resonance contrast agent should be installed, and when registering and positioning in optical navigation, the optical positioning marker bead 103 should be installed. By specially designing the two positioning marker bead 103, the center positions of the two beads can be exactly overlapped when the two beads are inserted into the same fixed pile.

[0188] Since the frame 101 can be regarded as a rigid body, the registration using the frame 101 is actually to find a point x=[x1, x2, x3] in the image space. T To the corresponding point y=[y1, y2, y3] in physical space T Rigid transformation: y = RX + T, where R is the rotation matrix and T is the displacement vector. The registration method is as follows:

[0189] First, let the patient try on frames 101 of different sizes and select a pair of positioning glasses that are firm and comfortable to wear.

[0190] Next, n magnetic resonance positioning marker balls 103 (n≥4) are installed on the positioning marker ball fixing pile 102 of the frame 101. The patient wears the positioning glasses for magnetic resonance scanning to obtain the coordinates of each positioning marker ball 103 in the image space: x i =[x 1i , x 2i , x 3i ] T , i=1,2,…,n.

[0191] Next, remove the magnetic resonance positioning marker balls 103, and install the same number of optical positioning marker balls 103 on the same positioning marker ball fixing pile 102. The patient wears positioning glasses for treatment and obtains the real-time coordinates of each optical positioning marker ball 103 under optical navigation. The positional relationship of each positioning marker ball 103 is determined based on the distance between them, and they are reordered to obtain the coordinates of each positioning marker ball 103 in the physical space: y i =[y 1i ,y 2i ,y 3i ] T.

[0192] Next, the centroid coordinates of each positioning mark ball 103 in the image space and the physical space are calculated respectively:

[0193] Next, the displacement vector of each positioning mark ball 103 relative to the center of mass is calculated:

[0194] Next, the covariance matrix of the coordinates of each positioning marker ball 103 in the image space and the physical space is calculated:

[0195] Next, perform singular value decomposition on the covariance matrix: H = UΛV T .

[0196] Next, calculate the rotation matrix of the coordinate transformation: R = VU T .

[0197] Next, calculate the displacement vector of the coordinate transformation:

[0198] The structure of the positioning frame is shown in the attached Figure 2 , Attachment Figure 3 shown.

[0199] When the patient receives the treatment of transcranial ultrasound stimulation, the back of the patient leans against the chair 210, the head rests on the headrest 211, and the lower jaw is fixed with the mandibular support 212. The headrest 211 is designed according to ergonomics, and is wrapped with a cushion, which can fit the head and prevent the relative displacement between the head and the chair 210. The headrest 211 can be raised and lowered to adapt to the height and head shape of different patients. The back of the lifting rod 207 of the headrest 211 is scaled to ensure that the position remains unchanged during the second and subsequent treatments. Since transcranial ultrasound stimulation generally does not pass through the occipital bone, the occipital bone covered by the headrest 211 does not affect the treatment plan. The highest point of the headrest 211 should be flush with the most protruding part of the back of the head to ensure the stability of the head and reduce the patient's discomfort. The mandibular support 212 is fixed to the headrest 211 by a strap to fix the patient's head. There is a buckle on the mandibular support 212, which can be fixed on the strip-shaped card slot of the strap to adjust the tightness to adapt to the head shape of different patients. There are scales on the card slot to ensure that the patient's head position remains unchanged during the second and subsequent treatments.

[0200] The positioning frame is mounted on the seat 210 through the lifting rod 207, the locking device 208, and the shaft sleeve 209. The lifting rod 207 controls the translation of the device in the Z direction, and can be moved by manual control or by a stepper motor. The lifting rod 207 is marked with a scale, and the minimum division is 1 mm. By tightening the locking device 208, the lifting rod 207 and the shaft sleeve 209 can be fixed to prevent relative movement.

[0201] On the lifting rod 207 is a ball screw cross slide, that is, a ball screw X-axis slide (referred to as "X-axis slide") 205 and a ball screw Y-axis slide (referred to as "Y-axis slide") 206, which can control the translation of the device in the X and Y directions. The ball screw X-axis slide 205 and the ball screw Y-axis slide 206 can be controlled to move by rotating the handle at the end, or by a stepper motor. The ball screw X-axis slide 205 and the ball screw Y-axis slide 206 are marked with scales, and the minimum division is 1 mm.

[0202] The top of the ball screw X-axis slide 205 is connected to the rotary positioner 204 by a thread, and the rotary positioner 204 can translate on the ball screw X-axis slide 205. The rotary positioner 204 is connected to the arc scale 203 by the meshing of the houndstooth disk, and the houndstooth disks can rotate relative to each other with an accuracy of 1°, which has the characteristics of fast positioning speed and high positioning accuracy. The rotary positioner 204 has an angle scale with a minimum division of 1°.

[0203] The arc scale 203 is fixed to the ultrasonic transducer holder 202 by a set screw. The ultrasonic transducer holder 202 can slide on the arc scale 203 to allow ultrasound to be incident from different angles. The minimum graduation of the arc scale 203 is 0.5°. The ultrasonic transducer 201 can be fixed on the ultrasonic transducer holder 202, so that the ultrasonic transducer 201 can move in the radial direction of the arc scale 203 to adapt to the neural regulation of targets at different depths. A marker for optical navigation can be installed on the ultrasonic transducer 201 to obtain its position coordinates.

[0204] The positioning method and process of this example in the application of transcranial ultrasound stimulation are shown in the attached Figure 4 As shown, the steps are:

[0205] First, the patient wears MRI-compatible positioning glasses that can be visualized in MRI and undergoes an MRI scan.

[0206] Next, the target position of the patient's transcranial ultrasound stimulation is planned, and the coordinates of the target and each mark point on the frame 101 of the positioning glasses in the image are determined. The most suitable incident position of the ultrasound transducer is planned according to methods such as transcranial sound field calculation.

[0207] Next, when receiving transcranial ultrasound stimulation for the first time, the patient leans back on the seat 210, adjusts the headrest 211 to a suitable position and records the scale of the lifting rod 207 of the headrest 211, then adjusts the tightness of the chinrest 212 and records the fixing position of the buckle. The optical navigation system is used to track the spatial physical position of the optical positioning marker ball 103 installed on the frame 101 of the positioning glasses to determine the coordinate information of the positioning glasses. The coordinates of each positioning marker point on the positioning glasses under optical navigation are aligned with the coordinates of the corresponding positioning marker ball 103 filled with magnetic resonance contrast agent in the magnetic resonance image to obtain the coordinate conversion matrix between the image space and the physical space. The coordinate conversion matrix is ​​used to calculate the coordinates of the target point in the physical space.

[0208] Next, the coordinates of the ultrasonic transducer 201 are determined using the optical navigation system. The center of the arc scale 203 of the frame is located at the target point by adjusting the ball screw X-axis slide 205, the ball screw Y-axis slide 206, and the lifting rod 207, ensuring that the incident direction of the ultrasonic transducer 201 is aligned with the target point. After the adjustment is completed, the scales of the ball screw X-axis slide 205, the ball screw Y-axis slide 206, and the lifting rod 207 are recorded so that the position can be adjusted quickly and accurately in subsequent use.

[0209] Next, the ultrasonic transducer holder 202, the arc scale 203 and the rotation positioner 204 are adjusted so that the ultrasonic transducer 201 can irradiate the ultrasound to the target point according to the path planned in step 220. After the adjustment is completed, the scales of the ultrasonic transducer holder 202, the arc scale 203 and the rotation positioner 204 are recorded so that the position can be adjusted quickly and accurately in subsequent use.

[0210] Then, during subsequent treatments, the patient no longer needs to use the optical navigation system and positioning glasses; he only needs to call up the scales recorded in steps 204 and 250 when he first received transcranial ultrasound stimulation, and adjust the corresponding components to the recorded scales. The patient sits on the chair 210 in the same posture as when he first received transcranial ultrasound stimulation, with his head resting on the headrest 211. At this time, the ultrasonic transducer 201 will contact the patient's head, and the contact point is the same as the position when he first received transcranial ultrasound stimulation. The relative position of the ultrasonic transducer 201 and the head is also the same as when the patient first received transcranial ultrasound stimulation, so that the target point can be accurately stimulated.

[0211] The main technical differences between this example and the prior art include:

[0212] First, this example provides a method and system for transcranial ultrasound stimulation positioning based on magnetic resonance imaging, optical navigation and stereo positioning framework, wherein positioning glasses that can be installed with positioning marker balls filled with magnetic resonance contrast agents or optical positioning marker balls are used to obtain head images and determine the coordinates of intracranial targets through magnetic resonance scanning, and then optical navigation is used to align the physical space with the image space to determine the coordinates of the target in the physical space. The system uses a 6-degree-of-freedom positioning framework that combines rectangular coordinates and spherical coordinates to fix the ultrasonic transducer. When the patient is first subjected to transcranial ultrasound stimulation, the ultrasonic transducer is accurately positioned by optical navigation so that the ultrasonic waves it emits are focused on the intracranial target, and the scales of each structure of the positioning framework are recorded at the same time. In subsequent treatments, there is no need to perform optical navigation again. It is only necessary to adjust the various structures of the positioning framework according to the scales recorded for the first time, so that the ultrasonic transducer can be quickly and accurately positioned to the treatment position to achieve repeated stimulation of the same target.

[0213] Furthermore, the positioning glasses in this example have the following characteristics: the frame is made of materials that are invisible under magnetic resonance to avoid artifacts during magnetic resonance scanning. In order to adapt to the head circumference of different patients, the frame design is available in a variety of sizes. A fixing device for mounting positioning marker balls is provided on the frame, and positioning marker balls filled with magnetic resonance contrast agents or optical positioning marker balls can be installed as needed. Among them, the balls filled with contrast agents can be clearly visualized during magnetic resonance scanning and are used to determine the position of the glasses in the image space; while the optical positioning marker balls are used for the optical navigation system to identify and locate, and obtain the spatial coordinate information of the glasses in the physical space. By flexibly switching between the two positioning marker balls on the frame, accurate alignment of the image space and the physical space can be achieved.

[0214] Furthermore, in this example, the positioning marker balls filled with magnetic resonance contrast agents and the optical positioning marker balls used are specially designed to ensure accuracy during the registration process. There is a cavity inside the ball filled with contrast agents for containing magnetic resonance contrast agents. The diameter of the cavity is the same as the outer diameter of the optical positioning marker ball, ensuring that the center positions of the two balls can completely overlap. By precisely controlling the amount of contrast agent filled, its volume is equal to that of the optical marker ball, avoiding the introduction of registration errors due to differences in the volume of the marker. When performing magnetic resonance scanning, positioning marker balls filled with contrast agents should be installed, and the position of the marking points should be determined by using their high signal display on the image; when performing optical navigation registration, they need to be replaced with optical positioning marker balls for identification and positioning by the optical navigation system. The two positioning marker balls are designed to be interchangeable. When inserted into the same fixture of the positioning glasses, the center positions of the balls completely overlap, thereby achieving high-precision registration of the image space and the physical space, effectively eliminating registration errors, and improving positioning accuracy.

[0215] Furthermore, in this example, the positioning frame has the following features: the headrest adopts an ergonomic design, the surface is covered with a soft cushion, and can be raised and lowered to improve patient comfort and adaptability. The lifting rod has a scale to accurately control the up and down position of the frame. The mandibular support can be adjusted to looseness through a buckle mechanism, and the buckle has a scale to achieve quantitative adjustment of the mandibular support position. The lateral and longitudinal translation of the frame is controlled by a ball screw cross slide, the slide scale is clear and readable, and the translation movement can be driven by a hand crank or a stepper motor, taking into account the flexibility of manual and electric operation. The slider and the arc scale are connected by a rat tooth disc, and the rat tooth discs can rotate relative to each other. The angle scale on the slider indicates the rotation angle in real time to achieve precise adjustment of the stimulation angle. The ultrasonic transducer holder can slide along the arc scale, and the tilt angle can be read, which is convenient for controlling the incident angle of the ultrasound beam. The ultrasonic transducer can move forward and backward on the holder to adjust the distance from the center of the arc scale and change the depth of the ultrasound focus. Optical positioning markers can be installed on the ultrasonic transducer housing to cooperate with the navigation system to obtain the spatial position coordinates of the transducer and achieve precise positioning. The positioning framework adopts a modular design, and each adjustment mechanism has a clear division of labor, is flexible and controllable, and uses a precise quantitative scale. It is easy to operate and has accurate positioning, providing a reliable hardware platform for transcranial ultrasound stimulation therapy.

[0216] The advantages of the above examples relative to the closest optical navigation and stereotactic framework solutions are further analyzed and compared below.

[0217] In clinical applications, transcranial ultrasound stimulation has the characteristic of requiring multiple repeated treatments at different times, while optical navigation needs to be re-aligned and positioned during each treatment, which is complex and time-consuming. In contrast, since the above-mentioned example has an adjustable and graduated head rest, mandibular rest, and positioning frame, the present application only requires optical navigation for alignment and positioning during the first treatment, and there is no need to use optical navigation for alignment and positioning again during the second and subsequent treatments. Instead, the positioning of transcranial ultrasound stimulation can be completed by using the structural scale information of the head rest, mandibular rest, and positioning frame recorded during the first navigation alignment.

[0218] Optical navigation uses anatomical points or surfaces in the registration of image space and physical space. They need to be selected in image space and physical space respectively. The selected points cannot completely coincide with the anatomical positions, which may cause errors. The process of selecting points in physical space is time-consuming, and errors may be caused by slight movements of the patient's head during the selection process. In contrast, the positioning glasses used in the above example in the registration can display marker points in both the image and the optical navigation, no longer relying on anatomical features, and are easy to operate and highly accurate.

[0219] Furthermore, the stereotactic frame requires local anesthesia on the patient's scalp, and then the frame is fixed to the skull. The patient wears the frame for magnetic resonance scanning, and the treatment path is planned according to the coordinates of the target in the magnetic resonance image. Considering that transcranial ultrasound stimulation requires multiple repeated treatments at different times in clinical practice, and the position of the frame fixed on the skull cannot be exactly the same each time, if this error is to be eliminated, the magnetic resonance imaging must be re-scanned, which is costly, cumbersome to operate, and has low patient acceptance. The above examples do not require multiple magnetic resonance imaging scans while ensuring accuracy, which reduces costs and increases the flexibility of treatment in time and space. In addition, the process of fixing the stereotactic frame to the skull is invasive, while the above examples are non-invasive, which can eliminate the risk of infection and greatly increase the patient's willingness to receive treatment.

[0220] The advantages of the above example over several existing positioning technologies are further analyzed below.

[0221] As mentioned above, this example consists of two parts, the positioning glasses and the positioning frame. The registration function implemented by the positioning glasses can be replaced by point registration based on anatomical features, surface registration based on anatomical features, and a stereo positioning frame fixed on the skull.

[0222] The point registration method based on anatomical features requires attaching magnetic resonance markers and optical markers to the head, or without attaching markers, finding several obvious anatomical markers on the magnetic resonance image, and locating these anatomical markers with a probe under optical navigation. In the process of selecting anatomical markers on the image and on the patient's head, the markers found cannot be accurate and there is an error between them and the actual anatomical position, which is called the fiducial localization error (FLE). In addition, for the marker method, there will be relative slippage between the marker and the skin, and it cannot completely overlap with the skin, resulting in marker localization errors; for the probe positioning method, it takes a long time, and the patient's head may move slightly during the probe positioning process, which will also result in marker localization errors.

[0223] The face registration method based on anatomical features requires extracting a point cloud of the scalp surface from the magnetic resonance image, then sliding a probe tool on the head surface, and using an infrared optical navigation device to record the point cloud formed by the sliding trajectory, and then registering the trajectory with the surface extracted from the magnetic resonance image. Taking the iterative closest point algorithm (ICP algorithm) as an example, face registration requires iterative calculation of point clouds with a large amount of data, and the calculation time required is much longer than the point registration method. In addition, the process of extracting the scalp surface with a probe under optical navigation is time-consuming, and the patient's head may move slightly during the probe positioning process, which will also cause marker positioning errors.

[0224] To use the stereotactic frame fixed on the skull for registration, local anesthesia is required on the patient's scalp, and then the frame is fixed on the skull. The patient wears the frame for magnetic resonance imaging, and the treatment path is planned based on the coordinates of the target in the magnetic resonance image. Considering that transcranial ultrasound stimulation requires multiple repeated treatments at different times in clinical practice, and the position of the frame fixed on the skull cannot be exactly the same each time, if this error is to be eliminated, the magnetic resonance imaging must be re-scanned, which is costly, cumbersome to operate, and has low patient acceptance. In addition, the process of fixing the stereotactic frame to the skull is invasive, which brings the risk of infection and reduces the patient's willingness to receive treatment.

[0225] As for the other part of the present application, namely the positioning frame part, although it can be replaced by the Leksell frame and other similar stereotactic frames used for neurosurgery, the traditional stereotactic frame needs to be fixed on the skull invasively, is small in size, and lacks the function of fixing the ultrasonic transducer. The positioning frame of this example does not need to be fixed on the skull, only the patient's head needs to be resting on the headrest of the positioning frame. The positioning frame part can also be replaced by an individually made helmet, on which the ultrasonic transducer can be fixed. However, the helmet solution needs to be designed and manufactured for different patients, which is time-consuming and costly.

[0226] It can be seen that the above example has the following advantages over several existing positioning technologies:

[0227] High registration accuracy: The positioning glasses use specially designed interchangeable positioning marker balls to ensure the precise overlap of marker points under both magnetic resonance scanning and optical navigation modes, effectively eliminating marker positioning errors and achieving high-precision registration.

[0228] Easy and quick operation: The positioning glasses are easy to wear and do not require additional skin markers, avoiding the tedious steps of applying markers and potential marker slip errors; at the same time, time-consuming manual probe positioning is also not required, which greatly simplifies the operation process and shortens the alignment time.

[0229] Non-invasive and comfortable: The positioning frame adopts a non-invasive design, which does not require the frame to be fixed on the skull, avoiding surgical trauma and infection risks, making it easier for patients to accept repeated treatments. The ergonomic headrest design further improves patient comfort.

[0230] Flexible and controllable: The positioning frame integrates a multi-degree-of-freedom adjustment mechanism, which can flexibly control the position and angle of the ultrasonic transducer to achieve precise focusing and positioning to meet the needs of different patients and treatments. The frame is also equipped with an ultrasonic transducer fixture to better integrate positioning and treatment functions.

[0231] Strong versatility: This example provides a set of standardized hardware platforms, which does not require the design and manufacture of helmets for each patient. It has a wide range of applications and relatively low production costs, which is more conducive to clinical promotion and application.

[0232] In summary, this example cleverly combines the positioning glasses and the positioning frame, overcomes the limitations of existing positioning technology, and has obvious advantages in alignment accuracy, ease of operation, patient comfort, flexible controllability and versatility, providing a more optimized positioning solution for transcranial ultrasound stimulation therapy.

[0233] The second embodiment of the present application relates to a positioning method for transcranial ultrasound neuromodulation, which adopts the positioning system in the first embodiment and includes the following steps:

[0234] S1: The patient wears the registration device, for example, positioning glasses, and performs magnetic resonance scanning to obtain the three-dimensional coordinates of the magnetic resonance positioning marker ball in the image space;

[0235] S2: replacing the magnetic resonance positioning marker ball with the optical positioning marker ball, and using an optical navigation system to obtain the three-dimensional coordinates of the optical positioning marker ball in the physical space;

[0236] S3: Based on the coordinates obtained in steps S1 and S2, a coordinate transformation relationship between the image space and the physical space is established through a rigid transformation algorithm;

[0237] S4: according to the preset transcranial ultrasound stimulation scheme, determine the three-dimensional coordinates of the ultrasound target point in the image space, and then use the conversion relationship established in step S3 to convert the target point coordinates into the physical space;

[0238] S5: adjusting the positioning frame, ultrasonic transducer holder, arc ruler and rotary positioner so that the focus of the ultrasonic transducer is aligned with the target coordinates converted in step S4, and recording the scale readings of each axis of the positioning frame at this time, so as to quickly reproduce the precise positioning later;

[0239] S6: Start transcranial ultrasound stimulation therapy;

[0240] S7: During subsequent treatment, it is only necessary to quickly adjust the positioning frame, ultrasonic transducer holder, arc ruler and rotation positioner to the corresponding scale readings recorded in step S5 during the first treatment, and then perform the intervention treatment of step S6 without repeating steps S1 to S5.

[0241] Optionally, in step S5, further comprising:

[0242] S51: Determine the coordinates of the ultrasonic transducer using an optical navigation system;

[0243] S52: by adjusting the X-axis slide, Y-axis slide and lifting rod of the positioning frame, the center of the arc scale of the positioning frame is located at the target point, ensuring that the incident direction of the ultrasonic transducer is aligned with the target point, and recording the scales of the X-axis slide, Y-axis slide and lifting rod after the adjustment is completed;

[0244] S53: Adjust the ultrasonic transducer holder, arc ruler and rotary positioner again, so that the ultrasonic transducer focuses the ultrasound to the target point according to the preset incident path. After the adjustment is completed, record the scales of the ultrasonic transducer holder, arc ruler and rotary positioner.

[0245] The first embodiment is a device embodiment corresponding to the present embodiment. The technical details in the first embodiment can be applied to the present embodiment, and the technical details in the present embodiment can also be applied to the first embodiment.

[0246] It should be noted that in the application documents of this patent, relational terms such as first and second 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 the 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. In the absence of further restrictions, the elements defined by the sentence "including one" do not exclude the existence of other identical elements in the process, method, article or device including the elements. In the application documents of this patent, if it is mentioned that an action is performed according to an element, it means that the action is performed at least according to the element, which includes two situations: performing the action only according to the element, and performing the action according to the element and other elements. Expressions such as multiple, multiple, and multiple include 2, 2 times, 2 kinds, and more than 2, more than 2 times, and more than 2 kinds.

[0247] All documents mentioned in this application are considered to be included in the disclosure of this application as a whole, so that they can be used as the basis for modification when necessary. In addition, it should be understood that after reading the above disclosure of this application, those skilled in the art can make various changes or modifications to this application, and these equivalent forms also fall within the scope of protection claimed in this application.

Claims

1. A positioning system for transcranial ultrasound neuromodulation, characterized in that: The system includes: The registration device comprises a rigid member for fixing on the patient's head, and a plurality of fixing posts fixed on the rigid member for detachably mounting positioning marker balls, wherein the fixing posts are replaceably mounted with magnetic resonance positioning marker balls or optical positioning marker balls; A positioning frame, including an adjustable head support and a mandibular support, for fixing the patient's head and ensuring that the position of the patient's head remains unchanged during multiple treatments; the positioning frame also includes an adjustable and graduated positioning device for adjusting the position and angle of the ultrasonic transducer, and the positioning device is adjusted in a combination of a rectangular coordinate system and a spherical coordinate system; The magnetic resonance positioning marker ball is used to obtain image space coordinates during magnetic resonance scanning, and is replaced by the optical positioning marker ball after scanning is completed to obtain physical space coordinates during optical navigation; a registration relationship is established using the image space coordinates and the physical space coordinates, and the focus of the ultrasonic transducer is aligned with the ultrasonic target position determined in the magnetic resonance image by adjusting the adjustable and scaled positioning device on the positioning frame; the scale on the positioning device is recorded during the first positioning, and in subsequent positioning, the positioning device is adjusted to the same scale, so that the focus of the ultrasonic transducer can be accurately and repeatedly positioned without re-registration; The process of establishing a registration relationship using image space coordinates and physical space coordinates includes: During magnetic resonance scanning, at least four magnetic resonance positioning marker balls (n≥4) are installed on the positioning marker ball fixing pile of the registration device, and the coordinates x of each magnetic resonance positioning marker ball in the image space are obtained. i =[x 1i , x 2i , x 3i ] T , where i = 1, 2, 3, ..., n; During optical navigation, the same number of optical positioning marker balls are installed on the same positioning marker ball fixing pile, and the coordinate y of each optical positioning marker ball in the physical space is obtained. i =[y 1i ,y 2i ,y 3i ] T ; Calculate the center of mass coordinates of the magnetic resonance positioning marker ball in the image space and the center of mass coordinates of the optical positioning marker ball in physical space Calculate the displacement vector of the magnetic resonance localization marker ball relative to the center of mass of the image space and the displacement vector of the optical positioning marker ball relative to the center of mass in physical space Calculate the covariance matrix of image space coordinates and physical space coordinates Perform singular value decomposition of the covariance matrix H = UΛV T , and get the rotation matrix R = VU T and displacement vector Establish the registration relationship between image space and physical space.

2. The system according to claim 1, characterized in that By adjusting and recording the rectangular coordinate frame and the spherical coordinate frame to specific scale positions during the first treatment, the same scale can be adjusted during subsequent treatments.

3. The system according to claim 2, characterized in that The registration device is selected from the group consisting of positioning glasses, masks, and eye covers.

4. The system according to claim 1, characterized in that The magnetic resonance positioning marker ball comprises a spherical cavity filled with a magnetic resonance contrast agent, and the surface of the optical positioning marker ball is provided with a reflective marker for reflecting infrared light of an optical navigation system.

5. The system according to claim 1, wherein: The inner diameter of the spherical cavity of the magnetic resonance positioning marker ball is the same as the outer diameter of the spherical surface of the optical positioning marker ball, so that the center positions of the two positioning marker balls coincide when they are inserted into the same fixing pile.

6. The system according to claim 2, characterized in that The rectangular coordinate frame includes: an X-axis slide, a Y-axis slide, a lifting rod, a locking device and a bushing; the spherical coordinate frame includes: an arc ruler and a rotation positioner; wherein the arc ruler and the rotation positioner are used to adjust the angle of the ultrasonic transducer, the X-axis slide, the Y-axis slide and the lifting rod respectively provide translational freedom along the X-axis, the Y-axis and the Z-axis, the locking device is used to lock the height of the lifting rod, and the bushing is used to connect the lifting rod and the seat.

7. The system according to claim 6, characterized in that The positioning frame is installed on the seat through a lifting rod, a locking device and a shaft sleeve. The lifting rod controls the positioning frame to translate along the Z-axis direction. The lifting rod is provided with a scale, and the relative position of the lifting rod and the shaft sleeve can be fixed by the locking device.

8. The system according to claim 6, characterized in that The lifting rod is provided with an X-axis slide and a Y-axis slide for controlling the translation of the positioning frame along the X-axis and Y-axis directions. The X-axis slide and the Y-axis slide are both provided with scales, and the minimum division is 1 mm.

9. The system according to claim 6, characterized in that The X-axis slide is provided with a rotary locator, which is meshed and connected with the arc scale through a hirth disk and can rotate relatively with a positioning accuracy of 1°. The rotary locator is provided with an angle scale with a minimum division of 1°.

10. The system according to claim 6, characterized in that The arc-shaped scale is fixed to the ultrasonic transducer holder by means of set screws. The ultrasonic transducer holder can slide along the arc-shaped scale to adjust the ultrasonic incident angle. The minimum division of the arc-shaped scale is 0.5°.

11. The system according to claim 10, characterized in that The ultrasonic transducer holder is used to fix the ultrasonic transducer and can adjust the radial position of the ultrasonic transducer along the arc scale to adapt to targets at different depths. In addition, a marker for optical navigation is installed on the ultrasonic transducer to obtain its position coordinates.

12. The system of claim 2, wherein: The positioning frame further includes an adjustable head support and a chin support, wherein: the head support is used to prevent the head from moving relative to the seat, and the height can be adjusted to adapt to the head shape and height of different patients, and the back of the head support has a scale for keeping the position of the patient's head unchanged during subsequent treatment; the chin support is fixed to the head support by an adjustable strap, and the strap has a buckle and a slot with a scale for adjusting the tightness to ensure that the position of the patient's head is fixed in the subsequent treatment The same as during the initial treatment.

13. The system of claim 1, wherein: The rigid part of the registration device is made of a material that is invisible under magnetic resonance, and the material is selected from at least one of polylactic acid, polyetheretherketone, polycarbonate and thermoplastic rubber.

14. A positioning method for transcranial ultrasound neuromodulation, characterized in that: The positioning system according to any one of claims 2 to 13 comprises the following steps: S1: The patient wears the registration device and performs magnetic resonance scanning to obtain the three-dimensional coordinates of the magnetic resonance positioning marker ball in the image space; S2: replacing the magnetic resonance positioning marker ball with the optical positioning marker ball, and using an optical navigation system to obtain the three-dimensional coordinates of the optical positioning marker ball in the physical space; S3: Based on the three-dimensional coordinates of the magnetic resonance positioning marker ball in the image space and the three-dimensional coordinates of the optical positioning marker ball in the physical space, a coordinate transformation relationship between the image space and the physical space is established through a rigid transformation algorithm; S4: determining the three-dimensional coordinates of the ultrasound target in the image space according to a preset transcranial ultrasound stimulation scheme, and then converting the coordinates of the target into the physical space by using the coordinate conversion relationship between the image space and the physical space; S5: adjusting the positioning frame, the ultrasonic transducer holder, the arc ruler and the rotary positioner so that the focus of the ultrasonic transducer is aligned with the converted target coordinates, and recording the scale readings of each axis of the positioning frame at this time, so as to quickly reproduce the precise positioning later; S7: During subsequent treatments, it is only necessary to quickly adjust the positioning frame, ultrasonic transducer holder, arc scale and rotation positioner to the corresponding scale readings recorded in step S5 during the first treatment.

15. The method according to claim 14, characterized in that The step S5 further comprises: S51: Determine the coordinates of the ultrasonic transducer using an optical navigation system; S52: by adjusting the X-axis slide, Y-axis slide and lifting rod of the positioning frame, the center of the arc scale of the positioning frame is located at the target point, ensuring that the incident direction of the ultrasonic transducer is aligned with the target point, and recording the scales of the X-axis slide, Y-axis slide and lifting rod after the adjustment is completed; S53: Adjust the ultrasonic transducer holder, arc ruler and rotary positioner again, so that the ultrasonic transducer focuses the ultrasound to the target point according to the preset incident path. After the adjustment is completed, record the scales of the ultrasonic transducer holder, arc ruler and rotary positioner.

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