Multi-element phased focused ultrasound transcranial rapid focusing method, device and storage medium
Patent Information
- Application Number
- CN202510002979.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-02
- Publication Date
- 2026-10-27
- Estimated Expiration
- 2045-01-02
AI Technical Summary
[0007]有鉴于此，本发明的目的在于提供一种多阵元相控聚焦超声经颅快速聚焦方法、设备及存储介质，以解决现有技术中主流聚焦调节方式，处理时间均较长，聚焦调节的实时性不足的问题
[0035]可以理解的是，本发明示出的技术方案，能够根据三维MRI和CT图像确定焦点和各阵元的坐标，计算颅骨和各部分脑组织中的声传播速度；根据坐标得到各阵元发射的超声波的传播路径；进而计算得出每条传播路径的总传递时间；计算最大传递时间与其他传播路径的总传递时间的差值；根据差值，计算得到对应阵元的相位差，从而调整对应阵元超声相位的输入。可以理解的是，本发明示出的技术方案，不需要进行反馈校正，有效提高了多阵元相控聚焦换能器的经颅聚焦效果，减少了计算时间，提高了相控焦点控制的实时性。
Smart Images
Figure CN119770875B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of medical device technology, specifically to a method, device, and storage medium for rapid transcranial focusing of multi-element phased focused ultrasound. Background Technology
[0002] In transcranial focused ultrasound (TCU) therapy, the precision of the focusing method is crucial to ensuring treatment effectiveness and safety. In practice, sound waves may deviate to varying degrees as they pass through the skull, leading to errors in the focusing point and thus affecting the treatment outcome. Therefore, during TCU treatment, the influence of the skull, especially the scattering and attenuation of ultrasound waves by the skull, must be overcome.
[0003] There are two main existing focusing adjustment methods: focus feedback correction technology and time reversal technology.
[0004] Focus feedback correction technology relies on real-time MRI imaging to monitor the propagation path and focusing position of ultrasound waves. By acquiring feedback information from the treatment area in real time, the system can dynamically adjust the ultrasound emission parameters, such as beam intensity, direction, and frequency, to ensure that the ultrasound waves are focused on the target brain region. The advantage of this technology is that it can be adjusted in real time during treatment, avoiding errors caused by differences in skull structure or individual variations, thus achieving higher precision treatment. However, due to inherent limitations in algorithms and hardware, and the need to wait for MRI imaging, the calibration time is too long, and it places high demands on the equipment.
[0005] Time-reversal technology utilizes an array of ultrasonic transducers to transmit ultrasound waves and receive reflected signals. The system records the received reflected signals and uses computer algorithms to reverse time, propagating the received signals back. This process is equivalent to "reversing" time, allowing the sound waves to be precisely focused on the target treatment area. The advantage of this method is that it does not require real-time image feedback; instead, it calculates the reversal of the received echo signals. This makes the time-reversal method more efficient in certain situations, especially where real-time imaging is difficult to implement. However, this method relies on a precise sound wave propagation model, is computationally complex and time-consuming, and makes it difficult to rapidly adjust the focus of multi-element phased-array focused ultrasound.
[0006] Therefore, current mainstream focusing and adjustment methods have long processing times and insufficient real-time focusing and adjustment capabilities. There is an urgent need to develop new multi-element phased transcranial focused ultrasound rapid focusing methods that do not rely on feedback adjustment and complex acoustic models. Summary of the Invention
[0007] In view of this, the purpose of this invention is to provide a method, device and storage medium for rapid transcranial focusing of multi-element phased focused ultrasound, in order to solve the problems of long processing time and insufficient real-time focusing adjustment in the mainstream focusing adjustment methods of the prior art.
[0008] According to a first aspect of the present invention, a method for rapid transcranial focusing of multi-element phased-array focused ultrasound is provided, comprising:
[0009] Acquire and register the patient's three-dimensional MRI and CT images of the brain to determine the focal point coordinates and the coordinates of each element of the transcranial focused ultrasound.
[0010] The velocity of sound propagation in the skull and various parts of brain tissue was determined based on voxel values in three-dimensional MRI and CT images of the brain.
[0011] Based on the coordinates of the focal position and the coordinates of each array element, the propagation path of the ultrasonic wave emitted by each array element to the focal position is obtained in a straight line.
[0012] Based on the sound propagation speed in the skull and various parts of the brain tissue, the propagation path of each array element is integrated to obtain the total transmission time of each propagation path.
[0013] The maximum transmission time is derived from the total transmission time of each propagation path, and the difference between the maximum transmission time and the total transmission time of other propagation paths is calculated.
[0014] Based on the difference, the phase difference of the corresponding array element is calculated, and the input of the ultrasonic phase of the corresponding array element is adjusted according to the phase difference.
[0015] Preferably, in the multi-element phased-array focused ultrasound transcranial rapid focusing method, the acquisition and registration of the patient's three-dimensional MRI and CT image data of the brain includes:
[0016] The positions of each element were marked on the patient's scalp, and the patient wore a helmet-mounted phased-array focused ultrasound transducer.
[0017] Three-dimensional MRI and CT images of the patient's brain were acquired.
[0018] Based on the three-dimensional MRI and CT images of the brain, the marked array element positions are used as reference points for registration to obtain a three-dimensional image matrix.
[0019] Preferably, determining the focal point coordinates and the coordinates of each element of the transcranial focused ultrasound includes:
[0020] A three-dimensional coordinate system is constructed based on the three-dimensional image matrix, and the coordinates of each pixel value are determined based on the distance between image pixels and the slice thickness.
[0021] The focal position coordinates and the position coordinates of each element are determined based on the marked positions of each element.
[0022] Preferably, the sound propagation velocity in the skull and various parts of brain tissue is determined based on voxel values in three-dimensional MRI and CT image data of the brain, including:
[0023] The sound propagation velocity of the skull is calculated based on the Henle value H of the pixels in the CT image.
[0024] 1500+1400(H / Hmax);
[0025] The sound propagation velocity in different parts of the brain tissue was determined based on the gray values in the MRI images. The sound propagation velocity was 1500 m / s at the location with a gray value of 0, 1475 m / s at the location with a gray value between 1 and 9, 1540 m / s at the location with a gray value between 10 and 20, 1546.3 m / s at the location with a gray value between 21 and 39, 1552.5 m / s at the location with a gray value between 40 and 50, 1546.3 m / s at the location with a gray value between 51 and 78, 1500 m / s at the location with a gray value between 81 and 220, and 3476 m / s at the location with a gray value greater than 221.
[0026] Preferably, based on the sound propagation velocity in the skull and various parts of brain tissue, the propagation path of each array element is integrally calculated to obtain the total transmission time of each propagation path, including:
[0027] The total distance of the propagation path of each array element is calculated based on the coordinates of the focal position and the coordinates of each array element.
[0028] For each propagation path: the propagation path is divided into N equal segments with half the minimum wavelength of the sound wave in the propagation path as the interval; the average sound speed of each segment is calculated based on the sound propagation speed in the skull and various parts of the brain tissue, and the sound propagation time of each segment is calculated based on the average sound speed; the sound propagation time of each segment on the propagation path is accumulated to obtain the total transmission time of the propagation path.
[0029] According to a second aspect of the present invention, a multi-element phased-array focused ultrasound transcranial rapid focusing device is provided, comprising:
[0030] Helmet-mounted multi-element phased-array focused ultrasonic transducer for transmitting ultrasonic signals;
[0031] The MRI and CT image data acquisition module is used to acquire and register three-dimensional MRI and CT image data of the patient's brain, and determine the focal point coordinates and the position coordinates of each element of the transcranial focused ultrasound.
[0032] The focusing calculation module is used to determine the sound propagation velocity in the skull and various parts of brain tissue based on the voxel values in the three-dimensional MRI and CT image data of the brain; to obtain the straight-line propagation path of the ultrasound waves emitted by each array element to the focal point based on the coordinates of the focal point and the coordinates of each array element; to perform integral calculation on the propagation path of each array element based on the sound propagation velocity in the skull and various parts of brain tissue to obtain the total transmission time of each propagation path; to obtain the maximum transmission time from the total transmission time of each propagation path, and to calculate the difference between the maximum transmission time and the total transmission time of other propagation paths; to calculate the phase difference of the corresponding array element based on the difference, and to adjust the input of the ultrasound phase of the corresponding array element based on the phase difference.
[0033] According to a third aspect of the present invention, a computer-readable storage medium is provided, which stores a computer program that, when executed by a processor, implements the method described in any of the preceding embodiments.
[0034] The technical solutions provided by the embodiments of the present invention may include the following beneficial effects:
[0035] It is understood that the technical solution presented in this invention can determine the coordinates of the focal point and each array element based on three-dimensional MRI and CT images, calculate the sound propagation velocity in the skull and various parts of brain tissue; obtain the propagation path of the ultrasound waves emitted by each array element based on the coordinates; then calculate the total transmission time of each propagation path; calculate the difference between the maximum transmission time and the total transmission time of other propagation paths; and calculate the phase difference of the corresponding array element based on the difference, thereby adjusting the input of the ultrasound phase of the corresponding array element. It is understood that the technical solution presented in this invention does not require feedback correction, effectively improving the transcranial focusing effect of the multi-element phased-array focusing transducer, reducing calculation time, and improving the real-time performance of phased-array focus control.
[0036] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description
[0037] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.
[0038] Figure 1 This is a schematic diagram illustrating the steps of a multi-element phased-array focused ultrasound transcranial rapid focusing method according to an exemplary embodiment;
[0039] Figure 2 This is a schematic diagram illustrating the positions of multiple array elements and the focal positions according to an exemplary embodiment;
[0040] Figure 3This is a schematic diagram of a single-section image of a brain after MRI and CT registration, according to an exemplary embodiment.
[0041] Figure 4 This is a schematic diagram of a cross-sectional sound velocity image according to an exemplary embodiment;
[0042] Figure 5 This is a schematic diagram illustrating the comparison of delay results for each array element according to an exemplary embodiment. Detailed Implementation
[0043] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the invention as detailed in the appended claims.
[0044] In one embodiment, Figure 1 This is a schematic diagram illustrating the steps of a multi-element phased-array focused ultrasound transcranial rapid focusing method according to an exemplary embodiment. See also... Figure 1 A method for rapid transcranial focusing of multi-element phased-array focused ultrasound is provided, comprising:
[0045] Step S11: Acquire and register the patient's three-dimensional MRI and CT images of the brain, and determine the focal point coordinates and the coordinates of each element of the transcranial focused ultrasound.
[0046] Step S12: Determine the sound propagation velocity in the skull and various parts of the brain tissue based on the voxel values in the three-dimensional MRI and CT image data of the brain.
[0047] Step S13: Based on the coordinates of the focal position and the coordinates of each array element, the straight-line propagation path of the ultrasonic wave emitted by each array element to the focal position is obtained.
[0048] Step S14: Based on the sound propagation speed in the skull and various parts of the brain tissue, perform integral calculations on the propagation path of each array element to obtain the total transmission time of each propagation path.
[0049] Step S15: Obtain the maximum transmission time from the total transmission time of each propagation path, and calculate the difference between the maximum transmission time and the total transmission time of other propagation paths.
[0050] Step S16: Calculate the phase difference of the corresponding array element based on the difference, and adjust the input of the ultrasonic phase of the corresponding array element based on the phase difference.
[0051] It is understood that the technical solution presented in this invention can determine the coordinates of the focal point and each array element based on three-dimensional MRI and CT images, calculate the sound propagation velocity in the skull and various parts of brain tissue; obtain the propagation path of the ultrasound waves emitted by each array element based on the coordinates; then calculate the total transmission time of each propagation path; calculate the difference between the maximum transmission time and the total transmission time of other propagation paths; and calculate the phase difference of the corresponding array element based on the difference, thereby adjusting the input of the ultrasound phase of the corresponding array element. It is understood that the technical solution presented in this invention does not require feedback correction, effectively improving the transcranial focusing effect of the multi-element phased-array focusing transducer, reducing calculation time, and improving the real-time performance of phased-array focus control.
[0052] In practice, when performing transcranial focused ultrasound (TCU) therapy, a helmet-mounted multi-element phased-array focused ultrasound transducer can be used to transmit ultrasound signals. See also... Figure 2 In this embodiment, a planar ultrasonic probe with 12 elements arranged in a 3x4 array is selected, such as... Figure 2 ① to ① shown The array element is labeled.
[0053] When performing step S11, the following is included:
[0054] The positions of each element are marked on the patient's scalp, and the patient wears a helmet-mounted phased-array focused ultrasound transducer; three-dimensional MRI and CT images of the patient's brain are acquired; based on the three-dimensional MRI and CT images of the brain, the marked positions of each element are used as reference points for registration to obtain a three-dimensional image matrix.
[0055] In practice, patients wear helmet-mounted phased-array ultrasound transducers, and use an adhesive water-based material to mark the positions of each element on the scalp. Then, three-dimensional MRI and CT images of the brain are acquired, and the marked element positions are used as reference points for registration.
[0056] It should be noted that determining the focal point coordinates and the coordinates of each element of the transcranial focused ultrasound includes: constructing a three-dimensional coordinate system based on the three-dimensional image matrix; determining the coordinates of each pixel value based on the distance between image pixels and the slice thickness; and determining the focal point coordinates and the coordinates of each element based on the marked positions of each element.
[0057] In practice, when constructing a three-dimensional coordinate system, the top left corner of the registered three-dimensional image matrix is taken as the origin, the first dimension of the matrix is the z-axis, the second dimension is the x-axis, and the third dimension is the y-axis. Then, the coordinates of each pixel value are determined according to the distance between image pixels and the slice thickness, and the coordinates of each array element and the focal coordinates are determined according to the marked array element positions.
[0058] like Figure 2The image shows the registered data of three-dimensional MRI and CT images of a patient's brain, along with the constructed three-dimensional coordinate system. Figure 2 The coordinates of array elements 1 to 12 shown are (35,43,73), (40,43,73), (45,43,73), (50,43,73), (35,48,73), (40,48,73), (45,48,73), (50,48,73), (35,53,73), (40,53,73), (45,53,73) and (50,53,73), respectively, and the coordinates of the focal point are (42, 60,42).
[0059] When performing step S12, it should be noted that the sound propagation velocity in the skull and various parts of the brain tissue is determined based on the voxel values in the three-dimensional MRI and CT image data of the brain. This includes: calculating the sound propagation velocity in the skull based on the Henle values of the pixels in the CT image; and determining the sound propagation velocity in various parts of the brain tissue based on the gray values in the MRI image.
[0060] In specific practice, such as Figure 3 The image shown is the MRI and CT registered image of a single section after registration in step S11. The sound propagation velocity of the skull is calculated as 1500 + 1400 (H / Hmax) based on the Henle value H of the pixels in the CT image. The sound propagation velocity in different parts of the brain tissue is determined based on the grayscale values in the MRI image. Specifically, the sound propagation velocity at a grayscale value of 0 is 1500 m / s, the sound propagation velocity at a grayscale value between 1 and 9 is 1475 m / s, and the sound propagation velocity at a grayscale value between 10 and 20 is... The positional sound propagation speed is 1540 m / s for values between 21 and 39, 1546.3 m / s for values between 40 and 50, 1552.5 m / s for values between 51 and 78, 1500 m / s for values between 81 and 220, and 3476 m / s for values greater than 221. Figure 4 for Figure 3 The sound velocity diagram corresponding to the cross-section shown.
[0061] When performing step S13, the propagation path and direction of the ultrasonic waves emitted by each array element to the focal point are determined in a straight line based on the focal point and the coordinates of each array element. Figure 2 The straight line shown is the acoustic propagation path from array element ⑤ to the target focus.
[0062] When performing step S14, it should be noted that, based on the sound propagation velocity in the skull and various parts of the brain tissue, the propagation path of each array element is integrally calculated to obtain the total transmission time of each propagation path, including:
[0063] The total distance of the propagation path of each array element is calculated based on the coordinates of the focal position and the coordinates of each array element.
[0064] For each propagation path: the propagation path is divided into N equal segments with half the minimum wavelength of the sound wave in the propagation path as the interval; the average sound speed of each segment is calculated based on the sound propagation speed in the skull and various parts of the brain tissue, and the sound propagation time of each segment is calculated based on the average sound speed; the sound propagation time of each segment on the propagation path is accumulated to obtain the total transmission time of the propagation path.
[0065] In practice, the total distance L of the propagation path of each array element is first calculated, and then the distance L is calculated as half of the minimum wavelength of the sound wave in the propagation path (λ). min / 2) Divide the distance into N equal segments, i.e., N = 2L / λ min The sound propagation time for each distance is estimated based on the average sound velocity of each path segment, and the total propagation time for each path is obtained by summing all the times along that path. In this embodiment, array element ⑤ is used as an example; the distance L from this element to the focal point can be calculated using the coordinates of array element ⑤ and the focal point, where L = 34 mm. In this embodiment, the fundamental frequency of the ultrasound is 0.5 MHz, corresponding to a minimum wavelength λ. min The minimum sound speed obtained in step S12 can be divided by the fundamental frequency, corresponding to λ. min If the distance is 3mm, then the path from array element ⑤ to the focal point can be divided into N = 23 segments. Based on the coordinates of array element ⑤, the focal point, and the path, the path is divided into N = 23 segments. The coordinates of each point in the middle of the path can be obtained by linearly inserting 22 points (N-1) at equal intervals along the x, y, and z directions. Then, based on the location of each small segment, the average sound velocity is calculated on the sound velocity map obtained in step S12. The sound propagation time of each segment is estimated by dividing the segment distance by the average sound velocity, and all times along the path are summed to obtain the total propagation time for each path. Step S14 is then performed on each array element to obtain the propagation time of each element's path.
[0066] In step S15, the phase difference of the corresponding array element is estimated based on the difference between the maximum transmission time obtained in step S14 and the transmission time of the sound propagation path of each array element. The phase difference of each array element calculated in this embodiment is shown in [reference needed]. Figure 5 . Figure 5 The paper also presents the results of simulations using K-wave software to demonstrate existing time-reversal methods for calculating delays.
[0067] from Figure 5 The results show that the method proposed in this invention is close to the results obtained by existing methods based on K-wave software and time reversal, indicating that the method of this invention is reliable.
[0068] However, it is worth noting that the method of the present invention calculates the above results in 0.1 seconds, while the calculation time based on K-wave software and time reversal method is 146.3 seconds.
[0069] Using the method described in this invention, the multi-element transcranial focusing method in this embodiment does not rely on feedback adjustment and complex acoustic models, and can realize a rapid focusing method for multi-element phased transcranial focusing ultrasound, reducing calculation time and improving the real-time performance of focusing adjustment.
[0070] Therefore, the multi-element phased focused ultrasound transcranial rapid focusing method and system provided by this invention have great application prospects in the treatment of brain tumors.
[0071] According to a second aspect of the present invention, a multi-element phased-array focused ultrasound transcranial rapid focusing device is provided, comprising:
[0072] Helmet-mounted multi-element phased-array focused ultrasonic transducer for transmitting ultrasonic signals;
[0073] The MRI and CT image data acquisition module is used to acquire and register three-dimensional MRI and CT image data of the patient's brain, and determine the focal point coordinates and the position coordinates of each element of the transcranial focused ultrasound.
[0074] The focusing calculation module is used to determine the sound propagation velocity in the skull and various parts of brain tissue based on the voxel values in the three-dimensional MRI and CT image data of the brain; to obtain the straight-line propagation path of the ultrasound waves emitted by each array element to the focal point based on the coordinates of the focal point and the coordinates of each array element; to perform integral calculation on the propagation path of each array element based on the sound propagation velocity in the skull and various parts of brain tissue to obtain the total transmission time of each propagation path; to obtain the maximum transmission time from the total transmission time of each propagation path, and to calculate the difference between the maximum transmission time and the total transmission time of other propagation paths; to calculate the phase difference of the corresponding array element based on the difference, and to adjust the input of the ultrasound phase of the corresponding array element based on the phase difference.
[0075] According to a third aspect of the present invention, a computer-readable storage medium is provided, which stores a computer program that, when executed by a processor, implements the method described in any of the preceding embodiments.
[0076] It is understood that the same or similar parts in the above embodiments can be referred to each other, and the contents not described in detail in some embodiments can be referred to the same or similar contents in other embodiments.
[0077] It should be noted that in the description of this invention, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means at least two.
[0078] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as will be understood by those skilled in the art to which embodiments of the invention pertain.
[0079] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.
[0080] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.
[0081] Furthermore, the functional units in the various embodiments of the present invention can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.
[0082] The storage media mentioned above can be read-only memory, disk, or optical disk, etc.
[0083] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0084] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.
Claims
1. A rapid focusing method for transcranial multi-element phased-array focused ultrasound, characterized in that, include: Acquire and register the patient's three-dimensional MRI and CT images of the brain to determine the focal point coordinates and the coordinates of each element of the transcranial focused ultrasound. The sound propagation velocity in the skull and various brain tissue regions was determined based on voxel values from 3D MRI and CT images of the brain. This included: calculating the sound propagation velocity in the skull as 1500 + 1400 (H / Hmax) based on the Henle value H of pixels in the CT images; and determining the sound propagation velocity in various brain tissue regions based on grayscale values in the MRI images, where the sound propagation velocity at a grayscale value of 0 is 1500 m / s, and the sound propagation velocity at grayscale values between 1 and 9 is 1475 m / s. The location sound propagation speed is 1540 m / s for gray values between 10 and 20, 1546.3 m / s for gray values between 21 and 39, 1552.5 m / s for gray values between 40 and 50, 1546.3 m / s for gray values between 51 and 78, 1500 m / s for gray values between 81 and 220, and 3476 m / s for gray values greater than 221. Based on the coordinates of the focal position and the coordinates of each array element, the propagation path of the ultrasonic wave emitted by each array element to the focal position is obtained in a straight line. Based on the sound propagation velocity in the skull and various parts of brain tissue, the propagation path of each array element is integrated to obtain the total transmission time of each propagation path. This includes: calculating the total distance of the propagation path of each array element based on the coordinates of the focal position and the coordinates of each array element; for each propagation path: dividing the propagation path into N equal segments with half the minimum wavelength of the sound wave in the propagation path as the interval; calculating the average sound velocity of each segment based on the sound propagation velocity in the skull and various parts of brain tissue, and calculating the sound propagation time of each segment based on the average sound velocity; and summing the sound propagation times of each segment on the propagation path to obtain the total transmission time of the propagation path. The maximum transmission time is derived from the total transmission time of each propagation path, and the difference between the maximum transmission time and the total transmission time of other propagation paths is calculated. Based on the difference, the phase difference of the corresponding array element is calculated, and the input of the ultrasonic phase of the corresponding array element is adjusted according to the phase difference.
2. The multi-element phased-array focused ultrasound transcranial rapid focusing method according to claim 1, characterized in that, The acquisition and registration of the patient's three-dimensional MRI and CT image data of the brain includes: The positions of each element were marked on the patient's scalp, and the patient wore a helmet-mounted phased-array focused ultrasound transducer. Three-dimensional MRI and CT images of the patient's brain were acquired. Based on the three-dimensional MRI and CT images of the brain, the marked array element positions are used as reference points for registration to obtain a three-dimensional image matrix.
3. The multi-element phased-array focused ultrasound transcranial rapid focusing method according to claim 2, characterized in that, Determine the coordinates of the focal point and the coordinates of each element of the transcranial focused ultrasound, including: A three-dimensional coordinate system is constructed based on the three-dimensional image matrix, and the coordinates of each pixel value are determined based on the distance between image pixels and the slice thickness. The focal position coordinates and the position coordinates of each element are determined based on the marked positions of each element.
4. A multi-element phased-array focused ultrasound transcranial rapid focusing device, characterized in that, include: Helmet-mounted multi-element phased-array focused ultrasonic transducer for transmitting ultrasonic signals; The MRI and CT image data acquisition module is used to acquire and register three-dimensional MRI and CT image data of the patient's brain, and determine the focal point coordinates and the position coordinates of each element of the transcranial focused ultrasound. The focusing calculation module is used to determine the sound propagation velocity in the skull and various parts of the brain tissue based on the voxel values in the three-dimensional MRI and CT images of the brain; to obtain the straight-line propagation path of the ultrasound waves emitted by each array element to the focal point based on the coordinates of the focal point and the coordinates of each array element; and to perform integral calculation on the propagation path of each array element based on the sound propagation velocity in the skull and various parts of the brain tissue to obtain the total transmission time of each propagation path. The maximum transmission time is derived from the total transmission time of each propagation path, and the difference between the maximum transmission time and the total transmission time of other propagation paths is calculated. Based on the difference, the phase difference of the corresponding array element is calculated, and the input of the ultrasonic phase of the corresponding array element is adjusted according to the phase difference; The sound propagation velocity in the skull and various brain tissue regions was determined based on voxel values from 3D MRI and CT images of the brain. This included: calculating the sound propagation velocity in the skull as 1500 + 1400 (H / Hmax) based on the Henle value H of pixels in the CT images; and determining the sound propagation velocity in various brain tissue regions based on grayscale values in the MRI images, where the sound propagation velocity at a grayscale value of 0 is 1500 m / s, and the sound propagation velocity at grayscale values between 1 and 9 is 1475 m / s. The location sound propagation speed is 1540 m / s for gray values between 10 and 20, 1546.3 m / s for gray values between 21 and 39, 1552.5 m / s for gray values between 40 and 50, 1546.3 m / s for gray values between 51 and 78, 1500 m / s for gray values between 81 and 220, and 3476 m / s for gray values greater than 221. Based on the sound propagation velocity in the skull and various parts of brain tissue, the propagation path of each array element is integrated to obtain the total transmission time of each propagation path. This includes: calculating the total distance of the propagation path of each array element based on the coordinates of the focal position and the coordinates of each array element; for each propagation path: dividing the propagation path into N equal segments with half the minimum wavelength of the sound wave in the propagation path as the interval; calculating the average sound velocity of each segment based on the sound propagation velocity in the skull and various parts of brain tissue, and calculating the sound propagation time of each segment based on the average sound velocity; and summing the sound propagation times of each segment on the propagation path to obtain the total transmission time of the propagation path.
5. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 1 to 3.