WO2017107230A1

WO2017107230A1 - Ultrasonic brain stimulation or regulation and control method and apparatus based on large-scale area array element

Info

Publication number: WO2017107230A1
Application number: PCT/CN2015/099509
Authority: WO
Inventors: 郑海荣; 钱明; 李永川; 邱维宝; 牛丽丽; 王丛知
Original assignee: 中国科学院深圳先进技术研究院
Priority date: 2015-12-25
Filing date: 2015-12-29
Publication date: 2017-06-29
Also published as: CN105536156A

Abstract

Disclosed are an ultrasonic brain stimulation or regulation and control method and apparatus based on a large-scale area array element. The method comprises: step 1, establishing a head three-dimensional digital model; step 2, arranging a virtual sound source at a position where a brain needs to be stimulated or regulated and controlled, and using the virtual sound source to emit ultrasonic waves to the surroundings; step 3, based on the head three-dimensional digital model, performing sound field simulation, simulating acoustic parameters of the ultrasonic waves, emitted by the virtual sound source, which arrive at an array element position after passing through brain tissues, a skull and an ultrasonic coupling apparatus, and performing simulation to obtain a voltage signal obtained by an ultrasonic transducer after piezoelectric conversion; and step 4, according to the obtained acoustic parameters and the voltage signal, performing time reversal, applying a voltage corresponding to the voltage signal to the array element, and emitting the ultrasonic waves, so as to enable the ultrasonic waves which pass through the skull to focus at the position of the virtual sound source in the brain, thereby performing ultrasonic brain stimulation or regulation and control.

Description

Ultrasonic brain stimulation or regulation method and device based on large-scale array element

Priority statement

This application claims the priority of the Chinese invention patent submitted on December 25, 2015, with the application number CN201510990909.0, and the invention name is "a large-scale array element-based ultrasonic brain stimulation or regulation method and device". All the contents of the invention patent are hereby incorporated by reference in its entirety.

Technical field

The invention belongs to the medical field, and in particular to an ultrasonic brain stimulation or regulation method and device based on large-scale array elements.

Background technique

Functional brain diseases (Parkinson's disease, Alzheimer's disease, epilepsy, depression, etc.) have become major global medical problems and a heavy social burden. The exact mechanism of functional brain disease remains unclear and lacks effective treatments, which remains a major global medical challenge. Following the German scientists in 1870, after more than 100 years of electrical stimulation, the cerebral cortex of dogs can trigger specific body reactions, electrical, magnetic, optical and other technologies combined with neuroscience have produced deep brain electrical stimulation, magnetic stimulation, and optical genes. Regulation and other nerve stimulation and regulation techniques. The emergence of these neuromodulation techniques has greatly promoted the rapid development of neuroscience and brain science research such as emotion, memory, and cognition, as well as brain disease intervention and therapeutic techniques and instrument applications. Then, neuromodulation tools such as electrode stimulation and optogenetics have limited their use in brain disease research because of trauma to the brain. Magnetic stimulation can only act on the superficial cortex and lacks spatial precision. The unique mechanical wave physical properties of ultrasonic waves and their mechanical effects control the new discovery of nerve cell electrical activity, making it a promising new means to achieve non-invasive nerve stimulation and brain disease research and treatment.

Techniques and tools for neural stimulation and loop regulation are important drivers of neuroscience development. The current goal of neural stimulation techniques is to modulate neuronal system function by regulating exogenous energy to a complete circuit to regulate neuronal activity. The combination of electrical, magnetic, and optical technologies and neuroscience has produced neural stimulation and regulation techniques such as deep brain electrical stimulation, magnetic stimulation, and light gene regulation.

Deep Brain Stimulation (DBS) is a target of the nucleus of the brain implanted into the brain. It can suppress the abnormal nerve function of the target cells through controllable high-frequency current stimulation, and achieve effective intervention and treatment of diseases. purpose. Since the first use of tremor control in 1987, the world has been More than 100,000 patients have implanted DBS devices, providing an effective treatment for many refractory brain diseases such as Parkinson's disease, depression, refractory epilepsy, dystonia, refractory pain, obsessive-compulsive disorder, etc. Intervention method. However, the application of DBS also has important limitations: clinically, through the craniotomy, 1 or 2 electrodes are implanted into the deep brain tissue. Stimulation of the nucleus is a permanent trauma to the brain tissue and nerve circuit, and the target cannot be replaced. It is difficult to achieve stimulation of more parts of the nuclei, and the entire power supply equipment must be surgically implanted into the body. The stimulating electrode applied to the brain of the individual will affect the normal function of the body. After the DBS electrode is used for a period of time, a glial cell sheath will form around the electrode, which not only affects the efficiency of the electrode, but also affects the normal function of the body. When electrical stimulation is applied, the applied electrical stimulation always causes an excitatory response, and only when the inhibitory nuclei are stimulated can the inhibitory response be caused. These shortcomings also limit the application of electrical stimulation techniques in regulating the neural circuit.

Transcranial Magnetic Stimulation (TMS) is a non-invasive technique in which a transient, high-voltage pulse generated by a magnetic coil placed on the scalp produces a magnetic field perpendicular to the plane of the coil that acts with the brain tissue and produces Inductive currents cause depolarization of nerve cells and produce evoked potentials. This technique can be used to evaluate neurophysiological conduction pathways and to try neurorehabilitative treatment for diseases such as depression, epilepsy, stroke, schizophrenia, and autism. However, TMS technology has bottlenecks such as insufficient depth of stimulation, inability to focus, low resolution of stimulation, and difficulty in determining the stimulus area.

The newly developed Optogenetics (Optogenetics) in the past decade has achieved the selective regulation of a certain microcirculation at the cellular level, that is, by giving lasers of different wavelengths to achieve excitability or inhibition of a certain loop. Regulation has strongly promoted the development of neuroscience. However, optogenetics technology activates light-sensitive channels by giving lasers of different wavelengths. Since the strong absorption of light by biological tissues severely limits the distance of light travel (only a few millimeters), it is necessary for patients or test animals. The corresponding brain regions are inserted into the fiber and the fiber catheter, which inevitably damage part of the brain region during operation, resulting in the loss of certain physiological functions of the nervous system.

Methods of modulating neural activity include invasive and non-invasive techniques. However, many of these techniques, such as DBS and optogenetic techniques, require surgical implantation of stimulating electrodes, which are invasive, expensive, and even dangerous processes. For example, surgical implantation of stimulating electrodes increases secondary medical risks such as infection. Although TMS is non-invasive, there are bottlenecks such as insufficient stimulation depth, inability to focus, low stimulation resolution, and difficulty in determining the stimulation area, which cannot be applied to deep brain stimulation.

Ultrasound, as a mechanical wave, is generated by the vibration of an object (sound source) and causes its propagation by compressing and expanding the medium. Medical ultrasound usually refers to sound waves with a frequency in the range of 20 kHz to 10 MHz. Super In addition to the general properties of waves, sound has an important feature, its attenuation in human tissues such as water and muscles is very small, and it can reach deeper human tissues. The interaction between medical ultrasound and human tissue mainly uses the basic physical properties of the interaction between sound waves and matter, and has three major acoustic effects: wave effect, mechanical effect and thermal effect. These effects have important applications or great potentials in biomedicine. Traditional ultrasound has evolved into two basic functions: imaging diagnosis and thermal ablation based on wave effect and thermal effect. The wave effect can be used in ultrasound imaging diagnostic techniques such as B-ultrasound, color Doppler ultrasound, and angiography, which are widely used in clinical practice; thermal effects can be used for thermal ablation of tumors and treatment of nucleus destruction, such as high-intensity focused ultrasound (HIFU).

The advantage of ultrasound nerve stimulation and regulation is its non-invasive nature. The latest scientific evidence for the neuromodulation of ultrasound at the molecular, cellular, animal, and human brain levels strongly demonstrates that ultrasound can penetrate the human skull non-invasively, effectively regulate synaptic plasticity, neuronal regulation, and deep brain nucleus.

In a patent application for a device and method for repairing cranial nerve function by transcranial ultrasound stimulation (Application No. CN201210576849.4), it discloses a device and method for repairing cranial nerve function by transcranial ultrasound stimulation, the device including a function signal a generator, a power amplifier, and an ultrasonic transducer, wherein the function signal generator generates a stimulation signal required for stimulation, and then amplifies the high voltage pulse signal required by the ultrasonic transducer through the power amplifier, and then passes the ultrasonic transducer The ultrasonic stimuli signal is obtained to stimulate the brain tissue, and the invention can realize the purpose of low power, high resolution and non-invasive nerve repair treatment.

In a patent application entitled Method and Apparatus for Using Ultrasound for Regulating Cellular Activity (Application No. CN201510378861.8), it is disclosed for the regulation of living cells (eg, in humans, animals, plants, insects, microorganisms, and other organisms) Method and apparatus for one or more activities of a discovered or derived cell. The methods of the invention include the application of ultrasound (e.g., low intensity low frequency ultrasound) to living cells to affect cells and modulate cellular activity. The device of the present invention includes one or more components that generate ultrasonic waves, such as an ultrasound transmitter, transducer, or piezoelectric transducer, composite transducer, CMUT, and can be configured as single or multiple transducers or settings The components in the array construction. The ultrasound can be of any shape and can be focused or unfocused.

In a patent application entitled Apparatus and Method for Regulating Brain Activity (Application No.: CN201080056295.4), it provides an apparatus and method for brain regulation. The device contains a body and components for activating the brain. Such components include ultrasonic transducers. The device is used to provide ultrasound to a brain structure in a subject wearing the device for performing a treatment of traumatic brain injury, affecting posture control, and influencing the police Consciousness, attention, and vigilance, providing memory control, altering cerebral vascular hemodynamics, minimizing stress, and enhancing behavioral behavior.

In the above three published patent schemes, the following deficiencies exist:

The first patented scheme uses a single-element ultrasound transducer. Although it is stated in the claims that the ultrasonic transducer is provided with a different diameter collimator or a self-focusing ultrasonic transducer. However, due to the non-uniformity of the skull and the strong scattering of ultrasound, whether using a collimator or a self-focusing ultrasonic transducer, the propagation path of the ultrasound through the skull is difficult to control, so it is difficult to achieve precise positioning.

The second patent has the following disadvantages: 1. Although it is stated in the claims that the ultrasonic component may comprise from 1 to 1000 array elements, the arrangement of the array elements does not give an optimized arrangement; 2, although the claims It is proposed that the ultrasonic transducer element is driven using an analog or digital waveform such that the stimulation waveform contains single or multiple ultrasound frequencies, but no individual drive parameters (such as voltage, time delay) are proposed for components in the ultrasound transducer array. ) to overcome the strong scattering of ultrasound due to skull non-uniformity, so that precise focusing can be produced in the deep brain after passing through the skull; 3. although it is stated in the claims that the ultrasonic component can include up to 1000 array elements, In some applications, a larger array arrangement (>1000) may be required to produce more accurate spatial focus.

The device proposed in the third patent comprises a body and a component for activating the brain, and provides ultrasound to a brain structure in a subject wearing the device to regulate brain activity. In the regulation of brain activity, it is necessary to stimulate a plurality of different positions in the brain, and the solution does not explain the three-dimensional accurate multi-point stimulation method in the deep brain through the ultrasound array and the precise control of the ultrasound array.

Summary of the invention

In view of the deficiencies of the prior art, the present invention proposes an apparatus and method for ultrasonic brain stimulation and regulation based on large-scale array elements. The device includes a large-area array ultrasonic transducer, an ultrasonic controller, an ultrasonic coupling device, and the like. The method is to control the ultrasonic transducer array to emit ultrasonic waves through an ultrasonic controller, and perform precise focusing on one or more positions in the deep brain region through the acoustic coupling device and the skull to perform acoustic stimulation or regulation.

In order to achieve the above object, the present invention provides an ultrasonic brain stimulation or regulation method based on large-scale area array elements, the method comprising: step 1, establishing a three-dimensional digital model of the head; and step 2, where the brain needs stimulation or regulation Setting a virtual sound source, and using the virtual sound source to transmit ultrasonic waves to the periphery; step 3, performing sound field simulation based on the three-dimensional digital model of the head, simulating the ultrasonic wave emitted by the virtual sound source After the tissue, the skull, and the ultrasonic coupling device, the acoustic parameters are obtained when the position of the element is reached, and the voltage signal obtained by the piezoelectric transducer after the piezoelectric transducer is obtained by simulation; step 4, according to the obtained acoustic parameter and voltage signal, Inverting the time, applying a voltage corresponding to the voltage signal to the array element, and transmitting the ultrasonic wave, so that the ultrasonic wave is focused through the skull at a virtual sound source in the brain to perform ultrasonic brain stimulation or regulation.

Further, in step 1, the method includes: acquiring head structure information and physical information including a skull and a brain tissue, and establishing a three-dimensional digital model of the head according to the head structure information and the physical information.

Further, in step 1, the method comprises: performing three-dimensional scanning on the head by using computed tomography or magnetic resonance imaging to acquire head structure information and physical information including the skull and brain tissue.

Further, the physical information of the head includes: density, sound attenuation.

Further, the acoustic parameters include: sound intensity, sound pressure, and time required for the ultrasonic wave to arrive.

In order to achieve the above object, the present invention also provides an ultrasonic brain stimulation or regulation device based on a large-scale array element, the device comprising: an ultrasonic generating device, an ultrasonic control device, and an ultrasonic coupling device; wherein the ultrasonic generating device includes An array element for transmitting and receiving ultrasonic waves; an ultrasonic coupling device for introducing ultrasonic waves emitted by the ultrasonic generating device into the head; and an ultrasonic control device comprising: a model building module for establishing a three-dimensional digital model of the head; a simulation module, configured to set a virtual sound source at a position where the brain needs stimulation or regulation, and use the virtual sound source to transmit ultrasonic waves to the surroundings, and perform sound field simulation based on the three-dimensional digital model of the head to simulate the virtual sound source emission After the ultrasonic wave passes through the brain tissue, the skull, and the ultrasonic coupling device, the acoustic parameters are obtained when the position of the transducer element is reached, and the voltage signal obtained by the piezoelectric transducer after the piezoelectric transducer is obtained by simulation; the control module is used according to the obtained The acoustic parameter and the voltage signal, the time is inverted, and the transducer is controlled Element is applied to the voltage corresponding to the voltage signal, so that said ultrasonic generating means for transmitting ultrasonic waves, ultrasonic waves through the skull to achieve virtual sound source at the focus of the brain, brain stimulation or modulation of ultrasound.

Further, the device comprises: a heat dissipating water cooling device for dissipating heat from the ultrasonic generating device.

Further, the model building module is further configured to acquire head structure information and physical information including a skull and a brain tissue, and establish a three-dimensional digital model of the head according to the head structure information and the physical information.

Further, the model building module is further configured to use computed tomography or magnetic resonance imaging Like three-dimensional scanning of the head, the head structure information and physical information including the skull and brain tissue are acquired.

The method and device for ultrasonic brain stimulation or regulation based on large-scale area array element proposed by the invention can realize precise focusing at multiple points in the brain, and realize single-point or multi-point dynamic ultrasonic stimulation or regulation.

DRAWINGS

The drawings described herein are provided to provide a further understanding of the invention, and are not intended to limit the invention. In the drawing:

1 is a flow chart of a method for ultrasonic brain stimulation or regulation based on large-scale area elements according to an embodiment of the present invention.

2 is a schematic structural view of an ultrasonic brain stimulation or regulation device based on a large-scale array element according to an embodiment of the present invention.

FIG. 3 is a schematic structural view of an ultrasonic control device according to an embodiment of the present invention.

FIG. 4A is a schematic diagram showing the arrangement of a two-dimensional array of 1024 array elements according to an embodiment of the present invention.

4B is a schematic diagram of a sound field focusing of a two-dimensional array of images at different depths according to an embodiment of the present invention.

5A is a simulation result of a single focus pressure field of an acoustic radiation force field of a four-sided array ultrasonic transducer according to an embodiment of the present invention.

5B is a simulation result of a four-focus pressure field of an acoustic radiation force field of a four-sided array ultrasonic transducer according to an embodiment of the present invention.

6A is a schematic diagram showing the result of direct focusing of a curved array ultrasonic transducer across a skull according to an embodiment of the present invention.

6B is a schematic diagram of a time-reversed transcranial focusing result of a curved array ultrasonic transducer according to an embodiment of the present invention.

FIG. 7A is a schematic diagram showing phase-controlled focusing results of a four-sided array transcranial multi-point focusing according to an embodiment of the present invention.

FIG. 7B is a schematic diagram showing the results of time reversal focusing of four-face array transcranial multi-point focusing according to an embodiment of the present invention.

detailed description

The technical means adopted by the present invention for achieving the intended purpose of the invention are further described below in conjunction with the drawings and preferred embodiments of the invention.

1 is a flow chart of a method for ultrasonic brain stimulation or regulation based on large-scale area elements according to an embodiment of the present invention. As shown in Figure 1, the method includes:

Step 1. Establish a three-dimensional digital model of the head.

Step 2: setting a virtual sound source at one or more locations where the brain needs stimulation or regulation, and using the virtual sound source to transmit ultrasonic waves to the surroundings; this step is to assume that the virtual sound source of the one or more locations emits ultrasonic waves to the surroundings.

Step 3: performing sound field simulation based on the three-dimensional digital model of the head, simulating acoustic parameters of the ultrasonic wave emitted by the virtual sound source after reaching the position of the array element through the brain tissue, the skull, and the ultrasonic coupling device, and simulating the ultrasonic conversion The voltage signal obtained after the piezoelectric transformer is converted; wherein the acoustic parameters of the head may include: sound intensity, sound pressure, and time required for the ultrasonic wave to arrive.

Step 4, according to the obtained acoustic parameters and voltage signals, time inversion, applying voltages corresponding to the voltage signals to the array elements, and transmitting ultrasonic waves, so that the ultrasonic waves pass through the skull at one or more virtual sound sources in the brain. Focus on ultrasound brain stimulation or regulation.

Further, in step 1, the method includes: acquiring head structure information and physical information including a skull and a brain tissue, and establishing a three-dimensional digital model of the head according to the head structure information and the physical information. The physical information of the head may include: density, sound attenuation, and the like.

Further, in step 1, the head can be scanned three-dimensionally using computed tomography (CT) or magnetic resonance imaging (MRI) or other three-dimensional imaging methods to obtain head structure information including the skull and brain tissue. Physical information.

Further, in step 3, the sound field simulation refers to the acoustic model based on the three-dimensional digital model of the head, using the numerical simulation software to simulate the ultrasonic wave emitted by the virtual sound source after reaching the position of the array element through the brain tissue, the skull, and the ultrasonic coupling device. The parameters, and in turn, simulate the voltage signal obtained by the piezoelectric transducer after piezoelectric transformation. Numerical simulation software includes, for example, Time Domain Finite Difference Software (FDTD), COMSOL, PZFlex, or other software.

Based on the above inventive concept, an embodiment of the present invention further provides an ultrasonic brain stimulation or regulation device based on a large-scale array element, as described in the following embodiments. Since the principle of solving the problem of the device is similar to the above-mentioned ultrasonic brain stimulation or regulation method based on large-scale array elements, the implementation of the device can be seen. The implementation of the above method will not be repeated here. As used hereinafter, the term "unit" or "module" may implement a combination of software and/or hardware of a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, hardware, or a combination of software and hardware, is also possible and contemplated.

2 is a schematic structural view of an ultrasonic brain stimulation or regulation device based on a large-scale array element according to an embodiment of the present invention. As shown in FIG. 2, the apparatus includes: an ultrasonic generating device 1, an ultrasonic coupling device 2, and an ultrasonic control device 3. Further, the device may further include a heat dissipating water cooling device 4.

The ultrasonic generating device 1 includes a transducer element for transmitting and receiving ultrasonic waves.

The ultrasonic coupling device 2 is configured to introduce ultrasonic waves emitted by the ultrasonic generating device into the head.

FIG. 3 is a schematic structural view of an ultrasonic control device according to an embodiment of the present invention. As shown in FIG. 3, the ultrasonic control device 3 includes:

a model building module 31, configured to establish a three-dimensional digital model of the head;

The simulation module 32 is configured to set a virtual sound source at a position where the brain needs stimulation or regulation, and use the virtual sound source to transmit ultrasonic waves to the surroundings, and perform sound field simulation based on the three-dimensional digital model of the head to simulate the virtual sound source emission. After the ultrasonic wave passes through the brain tissue, the skull, and the ultrasonic coupling device, the acoustic parameters are obtained when the transducer element is positioned, and the voltage signal obtained by the piezoelectric transducer after the piezoelectric conversion is obtained by simulation;

The control module 33 is configured to, according to the obtained acoustic parameter and the voltage signal, invert time, control a voltage corresponding to the voltage signal to the transducer array element, and enable the ultrasonic generating device to transmit an ultrasonic wave to implement Ultrasound is focused through the skull at a virtual sound source in the brain for ultrasound brain stimulation or regulation.

Further, the heat dissipating water cooling device 4 is configured to dissipate heat from the ultrasonic generating device.

In the present embodiment, the user can transmit a control command to the ultrasonic control device 3 through the computer, and the ultrasonic control device 3 receives the command to control the ultrasonic generating device 1. Since there is a gap between the ultrasonic generating device 1 (ultrasonic probe) and the head, there is air, and the ultrasonic wave has a large attenuation in the air, so it is necessary to provide the ultrasonic coupling device 3 to reduce the attenuation, and the ultrasonic generating device 1 emits The ultrasonic energy is coupled to the head. Since a large amount of heat is generated when the ultrasonic generating device 1 operates, the heat dissipating water cooling device 4 is required to dissipate heat.

In this embodiment, the model building module 31 is further configured to acquire head structure information and physical information including a skull and a brain tissue, and establish a three-dimensional digital model of the head according to the head structure information and the physical information.

In this embodiment, the model building module 31 is further configured to perform three-dimensional scanning on the head by using computed tomography or magnetic resonance imaging to acquire head structure information and physical information including a skull and a brain tissue.

In the present embodiment, the ultrasonic generating device 1 may include one or more components for generating ultrasonic waves, such as an ultrasonic transmitter, a transducer, a piezoelectric transducer, a piezoelectric polymer transducer, and a composite switch. Energy, gas matrix piezoelectric transducer, CMUT (capacitive micromachined ultrasonic transducer), PMUT (piezoelectric micromachined ultrasonic transducer).

The transducer elements in the ultrasonic generating device 1 are arranged in an array, which may be a planar array, a spherical surface, a curved surface or other structure or form suitable for the head.

The ultrasonic control device 3 may further comprise means for controlling the transmission and reception of data by the ultrasonic array element, the ultrasonic array element transmitting component controls the waveform, power and delay emitted by the one or more array elements, and controls the plurality of array elements to work together. The ultrasonic wave is emitted, the ultrasonic array element receives the component, and the control array element receives the echo.

The method and apparatus for ultrasonic brain stimulation or regulation based on large-scale array elements proposed by the present invention are compared with the first patent scheme in the background art. The first patented scheme uses a single-element ultrasound transducer. Due to the non-uniformity of the skull and the strong scattering of ultrasound, the propagation path of the ultrasound through the posterior skull is difficult to control, making it difficult to achieve precise positioning. The invention is based on a time inversion method, and uses an ultrasonic controller to control a large-area array ultrasonic transducer, which can achieve precise focusing at multiple points in the brain, and realize single-point or multi-point, dynamic ultrasonic stimulation and regulation.

Compared with the second patent scheme in the background art, the second patent scheme proposes an ultrasonic transducer using 1 to 1000 array elements, and no specific array arrangement is proposed, and no specific transducer array element driving is proposed. In this way, 1000 array elements are not necessarily enough to produce precise focus across the brain. The invention adopts a large-scale surface array ultrasonic transducer (one to ten thousand), based on a time inversion method, and uses an ultrasonic controller to apply individual driving parameters (such as voltage) to each array element of the large-area array ultrasonic transducer. , time delay), to overcome the strong scattering of ultrasound due to skull non-uniformity, the implementation of precise focus in the brain single or multiple points, to achieve multi-point, dynamic ultrasound stimulation and regulation.

Compared with the third patent scheme in the background art, the third patent scheme does not describe a three-dimensional accurate multi-point stimulation method in the deep brain by ultrasonic array and precise control of the ultrasound array. The invention controls the ultrasonic transducer array to emit ultrasonic waves through the ultrasonic control device, and performs precise focusing on one or more positions in the deep brain region through the acoustic coupling device and the skull to perform acoustic stimulation or regulation.

In order to carry out the above-mentioned large-scale array element-based ultrasonic brain stimulation or regulation method and device The invention is described in detail with reference to a few specific embodiments, which are not to be construed as limiting the invention.

Embodiment 1: Simulating a single point focusing of a two-dimensional area array probe in space, a two-dimensional area array as shown in FIG. 4A has a 32×32 square matrix composed of 1024 array elements. The center frequency of the piezoelectric element is 1.5 MHz, the element diameter is 5.0 mm, and the element spacing is 0.15 mm. Figure 4B shows the sound field focusing at different depths for a two-dimensional array.

Example 2: Simulation of the acoustic radiation force field distribution of a four-sided array ultrasonic transducer with a center frequency of 0.5 MHz and a depth of focus of 100-150 mm. Fig. 5A shows the simulation result of the single focus pressure field, and Fig. 5B shows the simulation result of the four focus pressure field.

Example 3: Simulation of the results of a curved array of ultrasonic transducers that were focused through the human skull in the deep brain. Using the skull image, a two-dimensional skull morphology model was obtained. The outer diameter of the skull is about 300mm. The stratification and non-uniformity of the skull itself are not considered for the time being, and the transverse wave effect in the skull is not considered. Only the skull is regarded as a uniform acoustic wave medium. The acoustic parameters are density 1658kg/m ³ and sound velocity 3360m/s. The brain tissue non-uniformity is not considered in the moment. The parts except the skull are set to water. The acoustic parameters are density 1000kg/m ³ and the sound speed is 1500m/ s.

FIG. 6A is a schematic diagram showing the result of direct focusing of the curved array ultrasonic transducer across the skull, and FIG. 6B is a schematic diagram showing the time-reversed transcranial focusing result of the curved array ultrasonic transducer, and the simulation results of the two figures show 512 array elements. The transcranial focus of the arc array. The frequency of the piezoelectric element is 1 MHz. Figure 6A shows the result of direct focusing of the semi-circular transducer array to the geometric center. Figure 6B shows the results of time-reversal transcranial focusing. The peak distribution of sound pressure was normalized to the maximum intracranial sound pressure value. Contrast the visible time inversion focus is smaller and the energy is more concentrated.

Example 4: Simulation of the results of transcranial focusing of a four-sided array ultrasound transducer. When energy is delivered from four directions, the focus shape is more regular, the focus size is smaller, and the energy convergence is higher (strong gradient field) than when the energy is delivered from a single direction. FIG. 7A is a schematic diagram showing phase-controlled focusing results of a four-sided array transcranial multi-point focusing according to an embodiment of the present invention, and FIG. 7B is a time inversion focusing of a four-sided array transcranial multi-point focusing according to an embodiment of the present invention. The results are schematic and quantitative comparisons are made. Since the amplitudes of the waveforms of the array elements are different in time, when the maximum emission energy of the time inversion is the same as the emission energy of the phase-controlled focus, the sound pressure amplitudes at the respective focal points are normalized and compared. The sound pressure amplitudes of the four focal points of the time inversion method are: 1.00, 1.00, 0.95, and 0.83; the sound pressure amplitudes of the four focal points of the phased focusing method are: 0.70, 0.18, 0.41, and 0.43, respectively. It can be seen from the results that the four-plane cross-cranial time inversion can achieve precise focusing of multiple points.

The above described specific embodiments of the present invention are further described in detail, and are intended to be illustrative of the embodiments of the present invention. All modifications, equivalent substitutions, improvements, etc., made within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

An ultrasonic brain stimulation or regulation method based on large-scale array elements, characterized in that the method comprises:

Step 1, establishing a three-dimensional digital model of the head;

Step 2: setting a virtual sound source at a position where the brain needs stimulation or regulation, and using the virtual sound source to emit ultrasonic waves to the surroundings;

Step 3: performing sound field simulation based on the three-dimensional digital model of the head, simulating acoustic parameters of the ultrasonic wave emitted by the virtual sound source after reaching the position of the array element through the brain tissue, the skull, and the ultrasonic coupling device, and simulating the ultrasonic conversion a voltage signal obtained by piezoelectric conversion of the energy device;

Step 4, according to the obtained acoustic parameters and voltage signals, time inversion, applying voltages corresponding to the voltage signals to the array elements, and transmitting ultrasonic waves, so that the ultrasonic waves are focused through the skull at a virtual sound source in the brain to perform ultrasound. Brain stimulation or regulation.
The method of claim 1 wherein in step 1, the method comprises:

Obtaining head structure information and physical information including skull and brain tissue, and establishing a three-dimensional digital model of the head based on head structure information and physical information.
The method of claim 2 wherein in step 1, the method comprises:

The head is scanned three-dimensionally using computed tomography or magnetic resonance imaging to obtain head structure information and physical information including the skull and brain tissue.
The method according to claim 2 or 3, wherein the physical information of the head comprises: density, sound attenuation.
The method of claim 1 wherein said acoustic parameters comprise: sound intensity, sound pressure, and time required for ultrasonic waves to arrive.
An ultrasonic brain stimulation or regulating device based on a large-scale array element, wherein the device comprises: an ultrasonic generating device, an ultrasonic control device, and an ultrasonic coupling device; wherein

An ultrasonic generating device comprising a transducer element for transmitting and receiving ultrasonic waves;

An ultrasonic coupling device for introducing ultrasonic waves emitted by the ultrasonic generating device into the head;

Ultrasonic control device, including:

a model building module for establishing a three-dimensional digital model of the head;

a simulation module for setting a virtual sound source at a location where the brain needs stimulation or regulation, and utilizing the virtual The sound source emits ultrasonic waves to the periphery, and the sound field simulation is performed based on the three-dimensional digital model of the head, and the ultrasonic wave emitted by the virtual sound source is simulated by the brain tissue, the skull, and the ultrasonic coupling device, and reaches the position of the transducer element element. Acoustic parameters, and simulation to obtain a voltage signal obtained by piezoelectric conversion of the ultrasonic transducer;

a control module, configured to invert time according to the obtained acoustic parameter and the voltage signal, and control a voltage corresponding to the voltage signal to the transducer array element, so that the ultrasonic generating device emits an ultrasonic wave to realize an ultrasonic wave Focusing through the skull at a virtual sound source in the brain for ultrasound brain stimulation or regulation.
The apparatus according to claim 6, wherein the apparatus comprises: a heat dissipating water cooling means for dissipating heat from the ultrasonic generating means.
The apparatus according to claim 6, wherein the model building module is further configured to acquire head structure information and physical information including a skull and a brain tissue, and establish a header according to the head structure information and the physical information. A three-dimensional digital model.
The device according to claim 6, wherein the model building module is further configured to perform three-dimensional scanning of the head by using computed tomography or magnetic resonance imaging to acquire a head structure including a skull and a brain tissue. Information and physical information.
The apparatus according to claim 8 or 9, wherein the physical information of the head comprises: density, sound attenuation.
The apparatus according to claim 6, wherein said acoustic parameters comprise: sound intensity, sound pressure, and time required for ultrasonic waves to arrive.