Transcranial ultrasonic stimulation system and control method thereof

Abstract

The invention relates to the technical field of ultrasonic medical instruments, and discloses a transcranial ultrasonic stimulation system and a control method thereof.The system comprises an ultrasonic circuit and an ultrasonic transducer, the ultrasonic circuit is composed of a power source, a main control circuit, an ultrasonic driving circuit, a matching circuit and a sampling circuit, and the ultrasonic transducer is composed of an ultrasonic vibration element and a storage chip; rated ultrasonic fundamental frequency of the ultrasonic transducer, relation curve data of output voltage and transducer output sound intensity, rated matching inductance, rated output voltage, rated input voltage and rated input current are stored in the storage chip. According to the invention, the sound intensity output by the ultrasonic transducer can be accurately controlled, and the change of the sound intensity output by the transducer can be monitored through the measurement parameters of the sampling circuit, so that the curve can be calibrated or the transducer can be abandoned in time, the intensity of ultrasonic stimulation can be controlled more accurately, the system can work under the optimal efficiency, and the system can work more accurately. And the method has wide adaptability.

Description

Technical Field

[0001] The present invention relates to the technical field of ultrasonic medical devices, and more specifically, to a transcranial ultrasound stimulation system and a control method thereof. Background Art

[0002] Transcranial Ultrasound Stimulation (TUS) is an emerging non-invasive brain stimulation technology that uses ultrasonic waves with specific frequencies and intensities to stimulate target areas of the brain. Transcranial ultrasound stimulation mainly utilizes low-intensity ultrasound, which does not produce obvious thermal effects and will not cause damage to brain tissue. Specific frequencies can ensure that ultrasound penetrates tissues such as the skull and reaches the brain. When ultrasonic waves propagate in biological tissues, they will cause the vibration of particles in the tissue, generating a mechanical effect. This mechanical effect can change the permeability of the neuron cell membrane, thereby regulating the activity of neurons. The mechanical effect of ultrasonic waves can induce the opening or closing of ion channels (such as calcium ion channels) on the cell membrane. Changes in the influx of calcium ions will affect the excitability of neurons, thereby regulating the conduction of nerve signals. Ultrasonic waves may also affect the synaptic transmission of neurons. By regulating the release of neurotransmitters from the presynaptic membrane or the sensitivity of receptors on the postsynaptic membrane, ultrasonic waves can change the information exchange between neurons.

[0003] Transcranial ultrasound stimulation technology is currently mainly applied to neuroscience research and the treatment of nervous system diseases, including: 1) used to study the functional connectivity of the brain; for example, by stimulating specific brain regions, the activity changes of other connected brain regions can be observed, thereby revealing the working mechanism of the brain neural network; 2) used to study neuronal plasticity; transcranial ultrasound stimulation can be used as an intervention means to observe the changes in the morphology and function of neurons in the brain after being stimulated by ultrasound, such as synaptic remodeling, etc.; 3) used for the treatment of neurological brain diseases such as Parkinson's disease; for example, some studies have attempted to regulate the neuronal activity in the basal ganglia region of the brain through transcranial ultrasound stimulation to improve the motor symptoms of patients, such as tremors, stiffness, etc.; 4) used for the treatment of mental diseases such as depression; transcranial ultrasound stimulation may play a certain therapeutic role by regulating the neural activity in related brain regions such as the prefrontal cortex.

[0004] The transcranial ultrasound stimulation system mainly includes an ultrasonic circuit and an ultrasonic transducer. The ultrasonic circuit is used to control the parameters of the ultrasound, such as frequency (the basic frequency F of the ultrasound used for transcranial stimulation is generally between 0.2 - 2 MHz), intensity (the spatial peak pulse average intensity I SPPA is usually within 30 W / cm 2 ), pulse width, etc. The ultrasonic transducer is a key component for generating ultrasonic waves. It can convert electrical energy into mechanical energy and emit ultrasonic waves with specific frequencies and intensities. At the same time, the device is usually equipped with a positioning device to ensure that the ultrasound is accurately focused on the target area of the brain.

[0005] The ultrasonic circuit applied to the transcranial ultrasound stimulation system generally consists of a power supply, a main control circuit, an ultrasonic drive circuit, a matching circuit, and a sampling circuit, and is used to drive an ultrasonic transducer to generate ultrasonic waves with specific frequencies and intensities. The power supply provides appropriate voltage and power for each part of the circuit in the system. The main control circuit includes a microprocessor (MCU, DSP, FPGA, etc.) and is responsible for the overall control of the circuit. The ultrasonic drive circuit mainly includes ultrasonic signal generation, ultrasonic signal processing, and power amplification, etc., and is the energy source of the ultrasonic transducer. The matching circuit ensures a high power transmission efficiency between the input circuit and the output circuit. When the circuit is well-matched, the coupling condition of the circuit is the best and the output power is the largest; otherwise, reflected power is generated, the energy obtained by the transducer is relatively small, the energy loss is relatively large, the circuit is easily burned out, and the circuit is damaged. The sampling circuit is used to sample the key control quantities in the system and feedback them to the main control circuit for processing, so that the main control circuit can master the real-time operation of the system and make appropriate control actions.

[0006] In addition, compared with traditional ultrasonic devices in the industrial or medical fields, the transcranial ultrasound stimulation system also has some special requirements in its own field. For example, in order to more precisely control the intensity of ultrasonic stimulation, it is necessary to more precisely control the ultrasonic intensity emitted by the ultrasonic transducer. After the ultrasonic transducer is used for a period of time, its performance will decline, and under the same electrical excitation, the intensity of the sound emitted by the transducer will change. This requires the transcranial ultrasound stimulation system to be able to monitor the performance changes of the transducer in real time and make adaptive control adjustments. Another example is that different ultrasonic stimulation frequencies will produce different neuromodulation effects, which requires the ultrasonic circuit to be able to adapt to transducers with different ultrasonic fundamental frequencies, or to adapt to multiple ultrasonic fundamental frequencies of the same transducer.

[0007] Therefore, based on the above special requirements of the transcranial ultrasound stimulation system, the present invention proposes a transcranial ultrasound stimulation system and its control method. Summary of the Invention

[0008] Aiming at the problems in the related art, the present invention proposes a transcranial ultrasound stimulation system and its control method to overcome the above technical problems existing in the existing related art.

[0009] To this end, the specific technical solutions adopted by the present invention are as follows:

[0010] According to one aspect of the present invention, a transcranial ultrasound stimulation system is provided, including an ultrasonic circuit and an ultrasonic transducer. The ultrasonic circuit consists of a power supply, a main control circuit, an ultrasonic drive circuit, a matching circuit, and a sampling circuit. The ultrasonic transducer consists of an ultrasonic vibration element and a storage chip. The storage chip stores the rated ultrasonic fundamental frequency F and output voltage V of the ultrasonic transducer oRelationship curve data with the output sound intensity I of the transducer SPPA ;

[0011] Among them, the power supply is used to provide voltage and power for the transcranial ultrasound stimulation system;

[0012] The main control circuit is used to overall coordinate and control the transcranial ultrasound stimulation system;

[0013] The ultrasonic drive circuit is used to generate and output electrical signals suitable for the ultrasonic transducer;

[0014] The matching circuit is used to ensure the power transfer efficiency between the input circuit and the output circuit;

[0015] The sampling circuit is used to sample and measure the input voltage, input current, and output voltage, and the input voltage and the input current are the DC input voltage and current of the power amplifier tube in the ultrasonic drive circuit, and the output voltage is the voltage applied to both ends of the ultrasonic transducer by the ultrasonic circuit;

[0016] The ultrasonic vibration element is used to generate ultrasound under the excitation of the ultrasonic circuit.

[0017] Furthermore, the power supply consists of a switching power supply SWITCHING POWER and a DC power supply DC / DC POWER. Among them, the switching power supply SWITCHING POWER converts the 220V / 50Hz AC mains into 48V or 36V DC power, and the DC / DC POWER DC power supply further converts it into the power supply with the voltage required by the ultrasonic drive circuit.

[0018] Furthermore, the main control circuit includes an MCU and its peripheral circuits, and the peripheral circuits include a power supply circuit, a clock circuit, a startup circuit, etc. that ensure the normal operation of the MCU.

[0019] Furthermore, the ultrasonic drive circuit consists of a power amplifier tube driver chip MOSFET DRIVER, a power amplifier tube Q1, and a power amplifier tube Q2. The MCU sends out two complementary PWM signals PWM1 / PWM2, which are amplified by the power amplifier tube driver chip MOSFET DRIVER and then input into the power amplifier tube Q1 and the power amplifier tube Q2 for power amplification.

[0020] Furthermore, the matching circuit consists of a transformer T0, a matching inductor L p and a matching capacitor C p ; The primary side of the transformer T0 has a center tap connected to the DC power supply DC / DC POWER, and the secondary side of the transformer T0 is connected to the ultrasonic transducer through the matching inductor L p and the matching capacitor C p ; The matching inductor L pIt is used to adjust the reactance component in the secondary circuit of transformer T0, making the secondary circuit of transformer T0 present a pure resistive property, thereby maximizing the energy output efficiency of the ultrasonic transducer; the matching capacitor C p It is used to reduce the influence of the change of the static capacitance of the ultrasonic transducer itself on the circuit matching.

[0021] Furthermore, the sampling circuit collects the output voltage V of the ultrasonic circuit o , and after dividing the voltage by resistor R1 and resistor R2, the signal of the output voltage V o is input into the signal processing module SIGNAL PROCESSING and the analog-to-digital converter ADC, and then is converted into a measured value V by the MCU mo ; the sampling circuit collects the input voltage V of the ultrasonic circuit i , and inputs the signal of the input voltage V i into the signal processing module SIGNAL PROCESSING and the analog-to-digital converter ADC, and then is converted into a measured value V by the MCU mi ; the sampling circuit collects the input current I of the ultrasonic circuit i , the input current I i flows through resistor R3, and the voltage at the front end of resistor R3 is collected and input into the signal processing module SIGNAL PROCESSING and the analog-to-digital converter ADC, and then is converted into a measured value I by the MCU mi .

[0022] Furthermore, the ultrasonic circuit can read the data stored in the storage chip of the ultrasonic transducer to control the system, specifically including: the ultrasonic circuit reads the rated ultrasonic fundamental frequency F of the transducer, the output voltage V o and the relationship curve data of the output sound intensity I SPPA of the transducer stored in the storage chip, and then generates an excitation electrical signal with a frequency of F and a voltage of V o to drive the ultrasonic transducer to emit ultrasonic waves with a frequency of F and a sound intensity of I SPPA .

[0023] Furthermore, the matching inductor L p is composed of fixed inductors. The fixed inductor is composed of one or several inductors connected in series and parallel, and the inductance value is fixed; the storage chip stores the rated output voltage V oe , the rated input voltage V ie and the rated input current I ie of the ultrasonic transducer.

[0024] According to another aspect of the present invention, a control method for a transcranial ultrasound stimulation system is provided, which is used to implement the control of the above transcranial ultrasound stimulation system. At the rated ultrasonic fundamental frequency F and the rated output voltage V oeUnder working conditions, according to the product V of the input voltage and the input current i *I i deviating from the rated value V ie *I ie to determine whether the ultrasonic transducer can be used normally.

[0025] Furthermore, this control method is used for monitoring the output sound intensity of the ultrasonic transducer, including:

[0026] Before leaving the factory, under the excitation of the rated ultrasonic fundamental frequency F, measure the output voltage V of the ultrasonic transducer o and the output sound intensity I of the ultrasonic transducer SPPA relationship curve data, rated output voltage V oe corresponding rated input voltage V ie and rated input current I ie ;

[0027] When leaving the factory, write the rated ultrasonic fundamental frequency F of the ultrasonic transducer, the relationship curve data between the output voltage V of the ultrasonic transducer o and the output sound intensity I of the ultrasonic transducer SPPA rated output voltage V oe corresponding rated input voltage V ie and rated input current I ie into the storage chip of the ultrasonic transducer;

[0028] During operation, after the ultrasonic transducer is connected to the ultrasonic circuit, the ultrasonic circuit reads the stored data from the storage chip and makes the system work under the rated ultrasonic fundamental frequency F and rated output voltage V oe and record the input voltage V at this time i and input current I i ;

[0029] When 1 - [V i *I i / (V ie *I ie )] < A, it means that the performance change of the ultrasonic transducer is within an acceptable range, then use it normally according to the relationship curve between the original output voltage V in the storage chip o and the output sound intensity I of the ultrasonic transducer SPPA ;

[0030] When A ≤ 1 - [V i *I i / (V ie *I ie )] ≤ B, then calibrate the ultrasonic transducer according to the relationship curve between the output voltage V o and the output sound intensity I of the ultrasonic transducer SPPA and use it again;

[0031] When 1 - [V i *I i / (V ie *I ie )] > B, the ultrasonic transducer is discarded, where the value range of parameter A is 1% - 10%, and the value range of parameter B is 10% - 20%.

[0032] Further, the matching inductor L p is composed of variable inductors, and the variable inductors are formed by several inductors with their inductance values doubling in sequence and connected in series, and whether each inductor is connected in series to the circuit is controlled by a relay; the rated matching inductor L pe of the ultrasonic transducer is stored in the storage chip.

[0033] Further, the rated output voltage V oe , rated input voltage V ie and rated input current I ie of the ultrasonic transducer are stored in the storage chip.

[0034] According to another aspect of the present invention, a control method for a transcranial ultrasound stimulation system is provided, which is used to implement the control of the above - mentioned transcranial ultrasound stimulation system. When working at the rated ultrasonic fundamental frequency F, rated matching inductor L pe and rated output voltage V oe , it is determined whether the ultrasonic transducer can be used normally according to the degree of deviation of the product V i *I i of the input voltage and input current from the rated value V ie *I ie .

[0035] Further, this control method is used for ultrasonic transducer matching and output sound intensity monitoring, including:

[0036] Before leaving the factory, under the excitation of the rated ultrasonic fundamental frequency F, the relationship curve data of the output voltage V o of the ultrasonic transducer and the output sound intensity I SPPA , rated matching inductor L pe , rated output voltage V oe , corresponding rated input voltage V ie and rated input current I ie are measured;

[0037] When leaving the factory, the rated ultrasonic fundamental frequency F of the ultrasonic transducer, the relationship curve data of the output voltage V o of the ultrasonic transducer and the output sound intensity I SPPA , rated matching inductor L pe , rated output voltage V oe, corresponding rated input voltage V ie and rated input current I ie A storage chip for writing into an ultrasonic transducer;

[0038] During operation, after the ultrasonic transducer is connected to the ultrasonic circuit, the ultrasonic circuit reads the stored data from the storage chip and allows the system to operate at the rated ultrasonic fundamental frequency F, rated matching inductance L pe and rated output voltage V oe , and record the input voltage V i and input current I i at this time;

[0039] When 1 - [V i *I i / (V ie *I ie )] < A, it means that the performance change of the ultrasonic transducer is within an acceptable range. Then, at the rated matching inductance L pe , it is used normally according to the relationship curve between the original output voltage V o in the storage chip and the output sound intensity I SPPA of the ultrasonic transducer;

[0040] When A ≤ 1 - [V i *I i / (V ie *I ie )] ≤ B, then the ultrasonic transducer is recalibrated and reused according to the relationship curve between the output voltage V o and the output sound intensity I SPPA of the ultrasonic transducer;

[0041] When 1 - [V i *I i / (V ie *I ie )] > B, then the ultrasonic transducer is discarded, where the value range of parameter A is 1% - 10%, and the value range of parameter B is 10% - 20%.

[0042] The beneficial effect of the present invention is that the transcranial ultrasound stimulation system of the present invention can accurately control the sound intensity output by the ultrasonic transducer according to the curve data of the output voltage V o and output sound intensity I SPPA stored in the storage chip of the ultrasonic transducer, and monitor the change of the output sound intensity performance of the transducer through the measurement parameters of the sampling circuit, so as to calibrate the above curve in time or discard the transducer, ensuring more accurate control of the intensity of ultrasonic stimulation. At the same time, the present invention can match ultrasonic transducers with different frequencies and matching inductances, or match different vibration frequencies of the same transducer, not only making the system operate at the optimal efficiency, but also having wide adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0044] Figure 1 is a schematic structural diagram of a transcranial ultrasound stimulation system according to an embodiment of the present invention;

[0045] Figure 2 is an example diagram of the relationship curve between the output voltage Vo and the output sound intensity ISPPA of the ultrasonic transducer in a control method of a transcranial ultrasound stimulation system according to an embodiment of the present invention;

[0046] Figure 3 is a flowchart of a control method of a transcranial ultrasound stimulation system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0047] To further illustrate the embodiments, the present invention provides drawings, which are part of the disclosure of the present invention. These drawings are mainly used to illustrate the embodiments and can be used to explain the operating principle of the embodiments in conjunction with the relevant descriptions in the specification. With reference to these contents, those of ordinary skill in the art should be able to understand other possible implementation manners and the advantages of the present invention. The components in the drawings are not drawn to scale, and similar component symbols are usually used to represent similar components.

[0048] According to an embodiment of the present invention, a transcranial ultrasound stimulation system and its control method are provided.

[0049] Now, the present invention will be further described in conjunction with the drawings and specific implementation manners. As Figure 1 - Figure 2 shown, according to one aspect of the present invention, a transcranial ultrasound stimulation system is provided, including an ultrasonic circuit and an ultrasonic transducer. The ultrasonic circuit is composed of a power supply, a main control circuit, an ultrasonic drive circuit, a matching circuit, and a sampling circuit;

[0050] Among them, the power supply is used to provide voltage and power for the transcranial ultrasound stimulation system;

[0051] Specifically, the power supply is composed of a switching power supply SWITCHING POWER and a DC power supply DC / DC POWER. Among them, the switching power supply SWITCHING POWER converts the 220V / 50Hz AC mains into 48V or 36V DC power, and the DC / DC POWER DC power supply further converts it into the power supply with the voltage required by the ultrasonic drive circuit. It should be noted that Figure 1Only the DC power supply for the ultrasonic drive circuit is shown, and the DC power supplies for other parts of the circuit are not shown;

[0052] The main control circuit is used to overall coordinate and control the transcranial ultrasound stimulation system;

[0053] Specifically, the main control circuit includes an MCU and its peripheral circuits. The MCU usually uses a chip of the STM32 platform, and the peripheral circuits include a power supply circuit, a clock circuit, a startup circuit, etc. to ensure the normal operation of the MCU;

[0054] The ultrasonic drive circuit is used to generate and output electrical signals suitable for the ultrasonic transducer;

[0055] Specifically, the ultrasonic drive circuit consists of a power amplifier transistor driver chip MOSFET DRIVER, power amplifier transistors Q1 and Q2. The power amplifier transistors Q1 and Q2 usually select field effect transistors. Two complementary PWM signals PWM1 / PWM2 sent by the MCU are amplified by the power amplifier transistor driver chip MOSFET DRIVER and then input into the power amplifier transistors Q1 and Q2 for power amplification; the frequency of the two complementary PWM signals is the rated ultrasonic fundamental frequency of the connected ultrasonic transducer. The input power of the power amplifier transistors Q1 and Q2 is provided by the DC power supply DC / DC POWER, and its input voltage is V i , and the input current is I i . The input voltage V i is adjusted by the PWM0 signal output by the DC power supply DC / DCPOWER through the MCU;

[0056] The matching circuit is used to ensure the power transfer efficiency between the input circuit and the output circuit;

[0057] Specifically, the matching circuit consists of a transformer T0, a matching inductor L p and a matching capacitor C p ; among them, the primary side of the transformer T0 has a center tap connected to the DC power supply DC / DC POWER, and the turns ratio is 1:1:N. The transformer is used to achieve impedance matching and reduce the secondary side impedance to the same order of magnitude as the internal resistance of the primary side power supply, so as to facilitate the ultrasonic drive circuit to output with the maximum efficiency. The matching inductor L p can be composed of a fixed inductor or a variable inductor. The fixed inductor is composed of one or several inductors connected in series and parallel, and the inductance value is fixed and cannot be changed during operation, so it can only be adapted to transducers with fixed performance parameters. The inductance value of the variable inductor can be changed during operation, so it can be adapted to transducers with different performance parameters. Figure 1 is composed of M inductors with inductance values doubling in sequence connected in series, and each inductor is controlled by a relay (K1-K M)Controls whether it is connected in series to the circuit. The on / off of all relays is controlled by the RL1-RL signals of the MCU. M The variable inductor composed of these M inductors can vary between L1 and (L1 + L2 + …… + L M ), and the resolution of the variation is L1. The matching capacitor C p can be added or not. This capacitor is mainly used to reduce the influence of the change in the static capacitance C0 of the transducer itself on the circuit matching. The matching inductor L p and the matching capacitor C p complete the tuning and matching, making the equivalent circuit of the ultrasonic transducer tend to be purely resistive when it works;

[0058] The sampling circuit is used to sample and measure the input voltage V i , the input current I i , and the output voltage V o . And the input voltage V i and the input current I i are the DC input voltage and current of the power amplifier tube in the ultrasonic drive circuit, and the output voltage V o is the voltage applied across the ultrasonic transducer by the ultrasonic circuit;

[0059] Specifically, the sampling circuit collects the output voltage V o of the ultrasonic circuit, which is also the voltage applied across the ultrasonic transducer. After dividing the voltage by resistors R1 and R2, the signal of the output voltage V o is input into the signal processing module SIGNALPROCESSING for shaping, filtering, amplification or comparison, etc., and then input into the analog-to-digital converter ADC, and then converted into a measured value V mo by the MCU; the sampling circuit collects the input voltage V i of the ultrasonic circuit, and the sampling principle is similar. Finally, it is converted into a measured value V mi through SIGNAL PROCESSING, ADC, and MCU; the sampling circuit collects the input current I i of the ultrasonic circuit. The input current I i flows through a tiny resistor R3 (typical value 10 - 20 mΩ), and the voltage at the front end of the sampling resistor R3 is collected to the signal processing module SIGNALPROCESSING, the analog-to-digital converter ADC, and then converted into a measured value I mi in the MCU;

[0060] The ultrasonic transducer UT consists of an ultrasonic vibration element TD and a storage chip SC capable of reading and writing data; the ultrasonic vibration element TD generates ultrasonic waves under the excitation of an ultrasonic circuit. The storage chip SC stores the parameter data of the ultrasonic transducer, and these data may include the rated ultrasonic fundamental frequency F of the transducer, the output voltage V o and the relationship curve data with the output sound intensity I of the transducer SPPA , the rated matching inductance L pe , the rated output voltage V oe , the corresponding rated input voltage V ie and the rated input current I ie , etc. Among them, the rated ultrasonic fundamental frequency F tells the ultrasonic circuit at what frequency to output the ultrasonic excitation signal; the V o -I SPPA curve is the basis for the ultrasonic circuit to control the sound intensity of the transducer; the rated matching inductance L pe achieves the best tuning and matching for the transducer; the rated output voltage V oe , the rated input voltage V ie , the rated input current I ie are the reference data for monitoring the performance changes of the ultrasonic transducer. The storage chip can be a chip that communicates based on the One Wire single-bus communication protocol, such as the EEPROM chip DS2431; or other types of storage chips, such as EEPROM chips based on multi-bus communication protocols such as I2C, SPI, Microwire, or FLASH chips based on multi-bus communication protocols such as SPI, Parallel, QSPI.

[0061] In an embodiment of the present invention, the parameter data of the ultrasonic transducer stored in the storage chip SC includes the rated ultrasonic fundamental frequency F of the transducer, the output voltage V o and the relationship curve data with the output sound intensity I of the transducer SPPA , which is applicable to an ultrasonic circuit with a fixed inductance for the matching inductance Lp. During operation, the ultrasonic circuit reads the rated ultrasonic fundamental frequency F of the transducer, the output voltage V o and the relationship curve data with the output sound intensity I of the transducer SPPA stored in the storage chip, and then generates an excitation electrical signal with a frequency of F and a voltage of V o to drive the ultrasonic transducer to emit ultrasonic waves with a frequency of F and a sound intensity of I SPPA . In this way, the transcranial ultrasonic stimulation system of the present invention can match ultrasonic transducers of different frequencies and output the ultrasonic sound intensity required during treatment.

[0062] In another embodiment of the present invention, the parameter data of the ultrasonic transducer stored in the storage chip SC, in addition to including the rated ultrasonic fundamental frequency F of the transducer, the output voltage V oThe relationship curve data with the output sound intensity I of the transducer SPPA also includes the rated matching inductance L pe , which is applicable to an ultrasonic circuit where the matching inductance Lp is a variable inductance. Using these data, the transcranial ultrasonic stimulation system of the present invention can match ultrasonic transducers with different frequencies and different matching inductances and output the ultrasonic sound intensity required during treatment, having a wider adaptability.

[0063] In another embodiment of the present invention, the parameter data of the ultrasonic transducer stored in the storage chip SC, in addition to including the rated ultrasonic fundamental frequency F of the transducer, the output voltage V o The relationship curve data with the output sound intensity I of the transducer SPPA and the rated matching inductance L pe , also includes the rated output voltage V oe , the corresponding rated input voltage V ie and the rated input current I ie . Based on these data, the transcranial ultrasonic stimulation system of the present invention can monitor the change in the output sound intensity performance of the transducer through a control method so as to calibrate in time or discard the transducer.

[0064] Figure 2 Shows an example of the relationship curve between the output voltage V o and the output sound intensity I of the ultrasonic transducer SPPA . This curve is obtained through experimental measurement. The hydrophone is placed at the focal position of the ultrasonic transducer sound field, and then different voltages are applied across the transducer. By measuring the sound intensity value at the focal position with the hydrophone, this curve is obtained. According to this curve, each sound intensity value corresponds to a voltage value, so as long as the voltage across the ultrasonic transducer is well controlled, different sound intensities can be output by the ultrasonic transducer. However, the performance of the ultrasonic transducer will change with the increase in service life. For example, the electro-acoustic conversion efficiency will gradually decrease, the internal resistance of the transducer itself will increase, and the resonant frequency of the transducer will also shift over time. These changes will cause the corresponding relationship between the voltage V o and the sound intensity I SPPA not to conform to the initial curve anymore. At this time, either re-measure this curve to calibrate the ultrasonic transducer or directly discard the transducer.

[0065] According to another aspect of the present invention, a control method for a transcranial ultrasonic stimulation system is provided. This control method is used for a circuit with a fixed matching inductance and can monitor the output sound intensity of the ultrasonic transducer. The system operates at the rated ultrasonic fundamental frequency F and the rated output voltage V oe , and V i *I i deviates from the rated value V ie *I ieThe larger it is, the greater the deviation of the output sound intensity of the ultrasonic transducer from the initial value; if at this time V i *I i deviates from the rated value V ie *I ie Within a certain range, the ultrasonic transducer can be recalibrated and then used; otherwise, the ultrasonic transducer needs to be discarded; specifically including:

[0066] (1) Before leaving the factory, under the excitation of the rated ultrasonic fundamental frequency F, measure the output voltage V o of the ultrasonic transducer and the relationship curve data between the output sound intensity I SPPA , the rated output voltage V oe , the corresponding rated input voltage V ie and the rated input current I ie ;

[0067] (2) When leaving the factory, write the rated ultrasonic fundamental frequency F of the ultrasonic transducer, the relationship curve data between the output voltage V o of the ultrasonic transducer and the output sound intensity I SPPA , the rated output voltage V oe , the corresponding rated input voltage V ie and the rated input current I ie into the storage chip of the ultrasonic transducer;

[0068] (3) During operation, after the ultrasonic transducer is connected to the ultrasonic circuit, the ultrasonic circuit reads the stored data from the storage chip, and makes the system work at the rated ultrasonic fundamental frequency F and the rated output voltage V oe , and records the input voltage V i and the input current I i at this time;

[0069] (4) When 1 - [V i *I i / (V ie *I ie )] < A, it means that the performance change of the ultrasonic transducer is within an acceptable range, and it can be used normally according to the relationship curve between the original output voltage V o of the ultrasonic transducer and the output sound intensity I SPPA ;

[0070] (5) When A ≤ 1 - [V i *I i / (V ie *I ie )] ≤ B, then calibrate the ultrasonic transducer according to the relationship curve between the output voltage V o and the output sound intensity I SPPA and reuse it;

[0071] (6) When 1 - [V i *I i / (V ie *I ie )] > B, the ultrasonic transducer is discarded, where the value range of the above parameter A is 1% - 10%, preferably 5%, and the value range of the parameter B is 10% - 20%, preferably 15%.

[0072] According to another aspect of the present invention, as Figure 3 the implementation steps of the control method of the transcranial ultrasound stimulation system of the present invention are based on Figure 1 a circuit containing a variable matching inductor;

[0073] Specifically, a control method for a transcranial ultrasound stimulation system, which is used for ultrasonic transducer matching and output sound intensity monitoring, specifically includes:

[0074] (1) Before leaving the factory, under the excitation of the rated ultrasonic fundamental frequency F, measure the relationship curve data of the output voltage V o of the ultrasonic transducer and the output sound intensity I SPPA , the rated matching inductor L pe , the rated output voltage V oe , the corresponding rated input voltage V ie and the rated input current I ie ;

[0075] (2) When leaving the factory, write the rated ultrasonic fundamental frequency F of the ultrasonic transducer, the relationship curve data of the output voltage V o of the ultrasonic transducer and the output sound intensity I SPPA , the rated matching inductor L pe , the rated output voltage V oe , the corresponding rated input voltage V ie and the rated input current I ie into the storage chip of the ultrasonic transducer;

[0076] (3) During operation, after the ultrasonic transducer is connected to the ultrasonic circuit, the ultrasonic circuit reads the stored data from the storage chip and makes the system work at the rated ultrasonic fundamental frequency F, the rated matching inductor L pe and the rated output voltage V oe , and records the input voltage V i and the input current I i at this time;

[0077] (4) When 1 - [V i *I i / (V ie *I ie)]<When A, it indicates that the change in the performance of the ultrasonic transducer is within an acceptable range, and it can be used normally according to the original output voltage V in the storage chip under the rated matching inductance L pe and the relationship curve between the output sound intensity I of the ultrasonic transducer o ; SPPA When A ≤ 1 - [V

[0078] *I i / (V i *I ie )] ≤ B, the ultrasonic transducer is recalibrated according to the relationship curve between the output voltage V ie and the output sound intensity I of the ultrasonic transducer o and then reused; SPPA When 1 - [V

[0079] *I i / (V i *I ie )] > B, the ultrasonic transducer is discarded, where the value range of the above parameter A is 1% - 10%, preferably 5%, and the value range of the parameter B is 10% - 20%, preferably 15%.

[0080] The above judgment criteria are based on the experimental phenomenon that under the fixed ultrasonic fundamental frequency F and output voltage V ie , the greater the deviation of V o *I i from the rated value, the greater the deviation of the ultrasonic sound intensity of the transducer from the initial value. It is also found through the experimental phenomenon that if at this time V i *I i deviates from the rated value V i *I ie within a certain range, the change in the performance of the transducer is mainly the change in its equivalent impedance, and the change in its resonant frequency is still small. The ultrasonic transducer can be recalibrated and then reused. If V ie *I i deviates from the rated value V i *I ie by a large amount, the change in the performance of the transducer includes not only the change in the equivalent impedance but also the change in the resonant frequency. At this time, under the excitation of the rated ultrasonic fundamental frequency, its electro-acoustic conversion efficiency will be low, and the ultrasonic transducer will no longer be suitable for continued use and needs to be discarded. ie In summary, by means of the above technical solution of the present invention, the transcranial ultrasound stimulation system of the present invention can be based on the output voltage V

[0081] stored in the storage chip of the ultrasonic transducer and the output sound intensity I o ; SPPAThe curve data precisely controls the sound intensity output by the ultrasonic transducer, and monitors the change of the sound intensity performance output by the transducer through the measurement parameters of the sampling circuit, so as to calibrate the above curve in time or discard the transducer to ensure more precise control of the intensity of ultrasonic stimulation. At the same time, the present invention can match ultrasonic transducers with different frequencies or matching inductors, or match different vibration frequencies of the same transducer, not only making the system work at the optimal efficiency, but also having wide adaptability.

[0082] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A transcranial ultrasound stimulation system, comprising an ultrasound circuit and an ultrasound transducer, wherein the ultrasound circuit is composed of a power supply, a main control circuit, an ultrasound drive circuit, a matching circuit and a sampling circuit, and the ultrasound transducer is composed of an ultrasound vibration element and a storage chip; characterized in that: The memory chip stores the rated ultrasonic fundamental frequency F and output voltage V of the ultrasonic transducer. o The transducer output sound intensity I SPPA Relationship curve data; Wherein, the power supply is used to provide voltage and power to the transcranial ultrasound stimulation system; The main control circuit is used to coordinate and control the transcranial ultrasound stimulation system as a whole; The ultrasonic driving circuit is used to generate and output an electrical signal suitable for the ultrasonic transducer; The matching circuit is used to ensure the power transmission efficiency between the input circuit and the output circuit; The sampling circuit is used to sample and measure the input voltage, input current, and output voltage, and the input voltage and input current are the DC input voltage and current of the power amplifier tube in the ultrasonic driving circuit, and the output voltage is the voltage applied by the ultrasonic circuit to both ends of the ultrasonic transducer; The ultrasonic vibration element is used to generate ultrasound under the excitation of the ultrasonic circuit.

2. A transcranial ultrasound stimulation system according to claim 1, characterized in that: The sampling circuit collects the output voltage V of the ultrasonic circuit o , the output voltage V is divided by resistors R1 and R2 o The signal is input into the signal processing module SIGNAL PROCESSING and the analog-to-digital converter ADC, and then converted into the measurement value V by the MCU. mo ; The sampling circuit collects the input voltage V of the ultrasonic circuit i , the input voltage V i The signal is input into the signal processing module SIGNAL PROCESSING and the analog-to-digital converter ADC, and then converted into the measurement value V by the MCU. mi ; The sampling circuit collects the input current I of the ultrasonic circuit i , input current I i The voltage flows through resistor R3, collects the voltage at the front end of resistor R3, and sends it to the signal processing module SIGNAL PROCESSING and analog-to-digital converter ADC, and then is converted into the measurement value I by MCU. mi .

3. A transcranial ultrasound stimulation system according to claim 1-2, characterized in that: The ultrasonic circuit can read the data stored in the ultrasonic transducer storage chip to control the system, specifically including: the ultrasonic circuit reads the rated ultrasonic basic frequency F and output voltage V of the transducer stored in the storage chip o The transducer output sound intensity I SPPA The relationship curve data is then generated with frequency F and voltage V o The excitation electrical signal drives the ultrasonic transducer to emit a sound with a frequency of F and a sound intensity of I SPPA Ultrasound.

4. A transcranial ultrasound stimulation system according to claim 3, characterized in that: The matching inductor L p The fixed inductor is composed of one or more inductors connected in series and parallel, and the inductance value is fixed; the storage chip stores the rated output voltage V of the ultrasonic transducer oe , Rated input voltage V ie And rated input current I ie .

5. A method for controlling a transcranial ultrasound stimulation system, for realizing the control of the transcranial ultrasound stimulation system as claimed in claim 4, characterized in that: At the rated ultrasonic fundamental frequency F and rated output voltage V oe Working under the condition, according to the product of input voltage and input current V i *I i Deviation from rated value V ie *I ie The degree of ultrasonic transducer can be used normally to judge whether it can be used normally.

6. The control method of a transcranial ultrasound stimulation system according to claim 5, characterized in that: The control method is used for monitoring the output sound intensity of an ultrasonic transducer, and includes: Before leaving the factory, under the excitation of the rated ultrasonic fundamental frequency F, measure the output voltage V of the ultrasonic transducer o The ultrasonic transducer output sound intensity I SPPA Relationship curve data, rated output voltage V oe , corresponding rated input voltage V ie And rated input current I ie ; When leaving the factory, the rated ultrasonic fundamental frequency F of the ultrasonic transducer and the output voltage V o The ultrasonic transducer output sound intensity I SPPA Relationship curve data, rated output voltage V oe , corresponding rated input voltage V ie And rated input current I ie Writing to the memory chip of the ultrasonic transducer; When working, after the ultrasonic transducer is connected to the ultrasonic circuit, the ultrasonic circuit reads the stored data from the memory chip and allows the system to operate at the rated ultrasonic fundamental frequency F and rated output voltage V oe Work under this condition and record the input voltage V i and input current I i ; When 1 - [V i *I i / (V ie *I ie )] < A, it indicates that the performance change of the ultrasonic transducer is within an acceptable range. Then, it is used normally according to the relationship curve between the original output voltage V o and the output sound intensity I SPPA of the ultrasonic transducer; When A≤1-[V i *I i / (V ie *I ie )]≤B, the ultrasonic transducer is set according to the output voltage V o The ultrasonic transducer output sound intensity I SPPA The relationship curve is calibrated and reused; When 1-[V i *I i / (V ie *I ie )]>B, the ultrasonic transducer is discarded, wherein the value range of parameter A is 1%-10%, and the value range of parameter B is 10%-20%.

7. A transcranial ultrasound stimulation system according to claim 3, characterized in that: The matching inductor L p The variable inductor is composed of a plurality of inductors whose inductance values ​​are doubled in sequence and connected in series, and each inductor is controlled by a relay to be connected in series to the circuit; the memory chip stores the rated matching inductance L of the ultrasonic transducer pe .

8. A transcranial ultrasound stimulation system according to claim 7, characterized in that: The memory chip stores the rated output voltage V of the ultrasonic transducer. oe , Rated input voltage V ie And rated input current I ie .

9. A method for controlling a transcranial ultrasound stimulation system, for realizing the control of the transcranial ultrasound stimulation system as claimed in claim 8, characterized in that: At rated ultrasonic fundamental frequency F, rated matching inductance L pe and rated output voltage V oe Working under the condition, according to the product of input voltage and input current V i *I i Deviation from rated value V ie *I ie The degree of ultrasonic transducer can be used normally to judge whether it can be used normally.

10. The control method of a transcranial ultrasound stimulation system according to claim 9, characterized in that: The control method is used for ultrasonic transducer matching and output sound intensity monitoring, including: Before leaving the factory, under the excitation of the rated ultrasonic fundamental frequency F, measure the output voltage V of the ultrasonic transducer o The ultrasonic transducer output sound intensity I SPPA Relationship curve data, rated matching inductance L pe , Rated output voltage V oe , corresponding rated input voltage V ie And rated input current I ie ; When leaving the factory, the rated ultrasonic fundamental frequency F of the ultrasonic transducer and the output voltage V o The ultrasonic transducer output sound intensity I SPPA Relationship curve data, rated matching inductance L pe , Rated output voltage V oe , corresponding rated input voltage V ie And rated input current I ie Writing to the memory chip of the ultrasonic transducer; When working, after the ultrasonic transducer is connected to the ultrasonic circuit, the ultrasonic circuit reads the stored data from the storage chip and allows the system to operate at the rated ultrasonic basic frequency F and rated matching inductance L. pe and rated output voltage V oe Work under this condition and record the input voltage V i and input current I i ; When 1 - [V i *I i / (V ie *I ie )] < A, it indicates that the performance change of the ultrasonic transducer is within an acceptable range. Then, at the rated matching inductance L pe , according to the relationship curve between the original output voltage V o in the storage chip and the output sound intensity I SPPA of the ultrasonic transducer, it is used normally; When A≤1-[V i *I i / (V ie *I ie )]≤B, the ultrasonic transducer is set according to the output voltage V o The ultrasonic transducer output sound intensity I SPPA The relationship curve is calibrated and reused; When 1-[V i *I i / (V ie *I ie )]>B, the ultrasonic transducer is discarded, wherein the value range of parameter A is 1%-10%, and the value range of parameter B is 10%-20%.

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