A low frequency low power focused ultrasound transcranial stimulation device

Abstract

The application discloses a low-frequency low-power focused ultrasonic transcranial stimulation device, which comprises a base, the lower end face of the base is provided with universal wheels around, the upper end face of the base is fixed with side plates on both sides, and the upper end faces of the two side plates are fixed with a top plate. The target point positioning is accurate, the positioning frame assembly is formed by the circumferential rotation of the annular sliding groove, the front and back translation of the first arc-shaped frame and the radial expansion and contraction of the second arc-shaped frame, three degrees of freedom space positioning is formed, all adjustments adopt hand screw rod locking, the structure is reliable and the cost is controllable, the elastic band and the telescopic supporting rod are used for adjusting the head circumference and the sliding groove height respectively, different age head types are adapted, the focusing patch is a concave self-focusing piezoelectric ceramic wafer, works in the 250-500 kHz low frequency band, has strong skull penetration, the focal point depth is adjusted in the range of 1cm to 5cm by replacing patches with different curvature radii or adjusting the excitation frequency characteristics, and the ultrasonic waves are accurately focused on the amygdala, the anterior cingulate cortex and other deep target areas.

Description

Technical Field

[0001] This invention relates to the field of transcranial ultrasound neuromodulation technology, and more particularly to a low-frequency, low-power focused ultrasound transcranial stimulation device. Background Technology

[0002] Transcranial low-intensity focused ultrasound (TIG) is an emerging non-invasive neuromodulation technique that uses low-intensity focused ultrasound to penetrate the intact skull, thereby modulating neural function. Existing TIG devices typically consist of an ultrasound signal generation module, a power amplification module, and an ultrasound transducer. The signal generator produces an excitation signal, which is amplified by the power amplifier and drives the ultrasound transducer to convert the electrical signal into ultrasound waves. The ultrasound waves are then delivered to the target area on the subject's head via a coupling medium. Low-frequency, low-power focused ultrasound devices generally operate at frequencies below 1 MHz, with sound intensity controlled within a safe threshold. They can penetrate the skull non-invasively and focus on deep brain regions, showing broad application prospects in the treatment and research of mental illnesses such as depression, epilepsy, and autism. Patent document CN111529970A discloses a head-mounted multi-channel ultrasound nerve stimulation device and method, which includes a head cover placed on the top of the head of the subject being tested, and three or more excitation channels installed on the head cover. Each excitation channel includes a capacitive micromechanical ultrasound transducer and an independent signal line, a common end set on the head cover, and a control end connected to the signal line of the capacitive micromechanical ultrasound transducer through the common end. The control end controls the ultrasonic focusing point of the CMUT array element through phased array modulation to realize multi-channel ultrasound nerve stimulation.

[0003] While the aforementioned devices achieve focused control of the ultrasound stimulation point through a head-mounted hood structure and multi-channel phased array modulation, the hood is a single-piece structure. It can only adjust the focal point position electronically, lacking mechanical multi-degree-of-freedom spatial positioning capabilities. This prevents precise adjustment of the transducer's radial distance and circumferential angle relative to the skull target, limiting the accuracy of the focused point in deep brain regions. Furthermore, these devices only provide ultrasound stimulation and lack synchronous acquisition and closed-loop safety control of EEG signals. They cannot monitor the subject's EEG activity in real time during stimulation and adjust the ultrasound output accordingly, resulting in insufficient safety. They also lack the function of switching between real and sham stimulation for double-blind clinical trials, making it difficult to meet the clinical research needs of fine neuromodulation studies such as those for autism. Therefore, we propose a low-frequency, low-power focused ultrasound transcranial stimulation device to address this problem. Summary of the Invention

[0004] The purpose of this invention is to provide a low-frequency, low-power focused ultrasound transcranial stimulation device to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A low-frequency, low-power focused ultrasound transcranial stimulation device, comprising: The base has casters installed around its lower end face, side plates fixed to both sides of its upper end face, a top plate fixed between the upper ends of the two side plates, a display screen installed on the upper end of the top plate, an energy module installed on the upper end face of the base, two support plates installed between the two side plates, and an ultrasound neuromodulation host module and an electroencephalogram monitoring module respectively installed on the upper ends of the two support plates. A positioning frame assembly, configured as a mechanically adjustable structure with at least two degrees of freedom, is used to position the ultrasonic transducer at a target location on the subject's head. Focusing transducer assembly, including a focused ultrasonic transducer with an operating frequency of less than 1 MHz; The electroencephalogram (EEG) monitoring module is electrically connected to the ultrasound neuromodulation host module, and the ultrasound neuromodulation host module is configured to automatically adjust the ultrasound output parameters according to the real-time EEG signals collected by the EEG monitoring module.

[0006] Preferably, each of the casters is equipped with a brake pedal; the display screen is a touch screen, and its back is connected to the top plate via an adjustable bracket.

[0007] Preferably, the energy module includes a rechargeable battery and a power management circuit, wherein the power management circuit has overvoltage and overcurrent protection units.

[0008] Preferably, the EEG monitoring module includes a signal amplifier, a bandpass filter, and an analog-to-digital converter connected in sequence; the ultrasound neuromodulation host module automatically reduces or pauses ultrasound output when epileptiform discharges are detected in the EEG signal.

[0009] Preferably, the focusing transducer assembly includes a mounting base mounted on the side plate surface. A winding rod is rotatably mounted on one side of the mounting base, and a wire-hanging rod is fixed to the surface of the winding rod. A servo motor connected to the winding rod is mounted on the other side of the mounting base. A transmission line is wound around the surface of the winding rod, and an ultrasonic electrode head is fixed to the extension section of the transmission line. A focusing patch is attached to the lower end face of the ultrasonic electrode head. The focusing patch is a concave self-focusing piezoelectric ceramic wafer with a working frequency range of 250-500kHz and an adjustable focal depth ranging from 1cm to 5cm. The transmission line is a radio frequency coaxial shielded wire with a flexible corrugated sheath. An emergency stop button is also mounted on the side plate surface, and the emergency stop button is connected in series in the power supply circuit between the energy module and the ultrasonic neuromodulation host module.

[0010] A positioning frame for transcranial ultrasound stimulation, comprising: The annular groove can rotate in all directions; The first arc-shaped frame can slide along the annular groove and has arc-shaped translational freedom; The second arc-shaped frame is connected to the first arc-shaped frame, and its interior is provided with a radially retractable I-shaped slide. The locking mechanism is used to lock the position of each degree of freedom.

[0011] Preferably, it also includes two headgear frames, with an elastic band installed between the two headgear frames. The elastic band is used to adjust the head circumference adaptation range, which is 45-65cm. Multiple support rods are installed on the upper surface of each of the two headgear frames. The support rods are telescopic structures, and the annular sliding grooves are installed on the upper surface of the multiple support rods.

[0012] Preferably, a slider is slidably sleeved in the inner cavity of the annular groove, a sliding seat is fixed on the upper end face of the slider, and the first arc-shaped frame is fixed between the two sliding seats; a threaded hole is opened on the side wall of the annular groove, and a locking bolt is connected in the threaded hole. The end of the locking bolt abuts against the surface of the slider to lock the position of the slider.

[0013] Preferably, the upper end face of the first arc-shaped frame is movably connected to an upper slide plate, the inner cavity of the upper slide plate is threadedly connected to a first hand-tightening screw, and the lower end face of the first hand-tightening screw is rotatably mounted with a lower clamping plate, and the second arc-shaped frame is fixed on both sides of the upper slide plate respectively; the inner thread of the I-shaped slide block is threadedly connected to a second hand-tightening screw, and the lower end face of the second hand-tightening screw is rotatably mounted with a pressure plate.

[0014] A method for switching between true and false stimulation in transcranial ultrasound stimulation, applied to a device, comprising: A random coding sequence is generated by the real / sham stimulation switching unit integrated within the ultrasound neuromodulation host module to determine whether the current treatment is a real stimulation mode or a sham stimulation mode. The random coding sequence is generated using a block randomization method. If it is a sham stimulation mode, turn off the ultrasonic energy output, while keeping the appearance and sound cues of the ultrasonic electrode head consistent with the real stimulation mode.

[0015] The beneficial effects of this invention are as follows: 1. In this invention, the target positioning is precise and the individual adaptability is strong. The positioning frame component forms a three-degree-of-freedom mechanical spatial positioning system through circumferential rotation of the annular slide, arc translation of the first arc frame, and radial extension and retraction of the I-shaped slide on the second arc frame. All adjustments are made by hand-tightening screws in conjunction with clamps or pressure plates for locking. The structure is reliable and the cost is controllable. The positioning is not lost when the power is off. The elastic band has a head circumference adaptation range of 45-65cm. The telescopic support rod adjusts the height of the slide to adapt to different ages and head shapes. The focusing patch is a concave self-focusing piezoelectric ceramic chip with a working frequency of 250-500kHz. It has strong penetrating power into the skull. The focal depth can be adjusted within the range of 1cm to 5cm by changing patches with different curvature radii or adjusting the excitation frequency characteristics to ensure that the ultrasound is accurately focused on deep target areas such as the amygdala and anterior cingulate cortex. 2. In this invention, the safety protection mechanism is complete and meets the rigor requirements of clinical research. The EEG monitoring module collects EEG signals in real time through signal amplifiers, bandpass filters and analog-to-digital converters. The ultrasound neuromodulation host module has a built-in closed-loop control algorithm. When abnormal EEG features such as epileptiform discharges are detected, the ultrasound output is automatically reduced or paused. The emergency stop button is connected in series in the power supply circuit and adopts a normally closed contact design. After an emergency is triggered, the host power supply is cut off instantly, which complies with the fail-safe principle and ensures personnel safety. The host integrates a real / sham stimulation switching unit. The real / sham state of each treatment is controlled by a random coding sequence. In sham stimulation mode, the ultrasound output channel is closed, but the external features such as indicator light flashing, fan running and buzzer prompts are completely consistent with real stimulation. Neither the operator nor the subject can distinguish them, ensuring the rigor of double-blind clinical trials. 3. In this invention, the cable is automatically managed, ensuring safe and orderly treatment operations. The focusing transducer component adopts a servo motor-driven winding rod and hanging rod structure. The transmission line is layered and wound on the surface of the winding rod and arranged with annular grooves to prevent the cable from tangling and knotting. During treatment, the servo motor automatically releases the cable, and the operator pulls the ultrasonic electrode head out to the required length and then fixes it to the front end of the I-shaped slide. When treatment is completed or the equipment is stored, the motor rotates in the opposite direction to automatically retract the transmission line, avoiding the risk of tripping and cable contamination caused by the cable dragging on the ground, keeping the treatment area clean and orderly. The transmission line uses radio frequency coaxial shielded cable, with an insulating medium filled between the inner conductor and the outer shielding layer to effectively suppress electromagnetic interference. The outer flexible corrugated tube sheath is wear-resistant and bend-resistant, extending the cable's service life and improving the long-term operational reliability of the equipment. 4. This invention features flexible and convenient operation, strong adaptability to various environments, and universal casters with brake pedals installed at the four corners of the base, allowing the entire machine to move freely in treatment rooms or laboratories. Stepping on the pedals locks the position and prevents accidental displacement. The gantry-style frame arranges the ultrasound neuromodulation host and EEG monitoring module in layers, resulting in a compact structure, low center of gravity, and stable operation. The display screen is installed above the top plate, allowing the operator to stand and look directly at the screen to complete stimulation parameter settings, view EEG waveforms, and retrieve files, reducing fatigue from looking down and improving human-computer interaction comfort and work efficiency. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the front view of a low-frequency, low-power focused ultrasound transcranial stimulation device proposed in this invention. Figure 2 This is a block diagram of the internal structure of the ultrasound neuromodulation host module in this invention; Figure 3 This is a block diagram of the internal structure of the EEG monitoring module in this invention; Figure 4 This is a flowchart of the closed-loop control algorithm in this invention; Figure 5 This is a schematic diagram showing the relationship between the operating frequency and the skull penetration attenuation in this invention; Figure 6 This is a schematic diagram showing the relationship between the operating frequency and the focal spot diameter in this invention; Figure 7 This is a schematic diagram of an embodiment of an ultrasonic transducer nerve stimulation method. Figure 8 This is a schematic diagram of the structure of the pallet in this invention; Figure 9 This is a cross-sectional view of the annular groove in this invention. Figure 10 This is a schematic diagram of the connection between the first arc-shaped frame and the second arc-shaped frame in this invention; Figure 11 This is a schematic diagram of the connection between the pressure plate and the ultrasonic electrode head in this invention; Figure 12 This is a schematic diagram of the focusing transducer component in this invention.

[0017] In the diagram: 1. Base; 2. Casters; 3. Side panel; 4. Top panel; 5. Display screen; 6. Energy module; 7. Support plate; 8. Ultrasonic neuromodulation main unit module; 9. EEG monitoring module; 10. Positioning frame assembly; 1001. Headgear frame; 1002. Elastic band; 1003. Support rod; 1004. Annular groove; 1005. Slider; 1006. Sliding seat; 1007. First arc-shaped frame; 1008 1009. Upper sliding plate; 1010. First hand-tightening screw; 1011. Lower clamping plate; 1012. Second arc-shaped frame; 1013. I-shaped slide block; 1014. Second hand-tightening screw; 1015. Pressing plate; 11. Focusing transducer assembly; 1101. Mounting base; 1102. Rewinding rod; 1103. Hanging rod; 1104. Servo motor; 1105. Transmission line; 1106. Ultrasonic electrode head; 1107. Focusing patch. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0019] Reference Figure 1 - Figure 12 A low-frequency, low-power focused ultrasound transcranial stimulation device, comprising: The base 1 has casters 2 installed around the lower end face of the base 1. Side plates 3 are fixed on both sides of the upper end face of the base 1. A top plate 4 is fixed between the upper ends of the two side plates 3. A display screen 5 is installed on the upper end face of the top plate 4. An energy module 6 is installed on the upper end face of the base 1. Two support plates 7 are installed between the two side plates 3. An ultrasound neuromodulation host module 8 and an electroencephalogram monitoring module 9 are respectively installed on the upper ends of the two support plates 7. Ultrasound neuromodulation host module 8: The ultrasound neuromodulation host module 8 is the core excitation signal generation and control unit of the device. It adopts a modular plug-in structure and is arranged in a metal shielded box. The front panel of the box is equipped with a power indicator, a running status indicator, a true / false stimulation mode indicator and a buzzer sound hole. The rear panel is equipped with a power input interface, an EEG signal input interface, a servo motor control interface, an emergency stop button interface and an ultrasound excitation signal output interface.

[0020] The chassis mainly includes the following functional units: The signal generation unit uses a direct digital frequency synthesizer to generate sinusoidal excitation signals with frequencies of 250-500kHz, a frequency resolution of 1Hz, and a frequency stability of ±0.1%. The signal generation unit is programmable to set the pulse repetition frequency and the duty cycle, with the pulse repetition frequency adjustable from 10-1000Hz and the duty cycle adjustable from 1-50%. The power amplification unit uses a linear power amplifier to amplify the low-level signal output from the signal generation unit to the power level required to drive the focusing transducer component. The power amplification unit is equipped with an output power monitoring circuit, which detects the output power in real time and feeds it back to the control unit. When the output power exceeds the preset safety threshold, the output is automatically limited. The control unit, with a microprocessor at its core, internally stores closed-loop control algorithm programs and real / false stimulation switching control programs. The control unit receives digital EEG signals sent by the EEG monitoring module 9 via the EEG signal input interface, and runs the closed-loop control algorithm to analyze EEG characteristic parameters in real time. The closed-loop control algorithm process is as follows: First, the EEG signal undergoes 50Hz power frequency notch filtering and 0.5-70Hz bandpass filtering preprocessing to remove power frequency interference and high / low frequency noise; then, characteristic parameters such as power spectral density, spike index, and kurtosis of each frequency band are extracted; next, the characteristic parameters are compared with preset abnormal judgment criteria. The abnormal judgment criteria are a spike index exceeding three times the baseline value and lasting for more than 100ms, or an alpha band power drop of more than 50% within one second. When the detection results meet the abnormal criteria, the control unit automatically executes protective actions, including reducing the output power to a safe level or completely suspending ultrasound output, while simultaneously driving the front panel indicator light to flash and the buzzer to sound an alarm. After the EEG characteristics return to normal, the system can be manually confirmed by the operator or automatically resume treatment output.

[0021] The true / false stimulation switching unit is integrated inside the control unit and is controlled by a random coding sequence. The random coding sequence is generated using a block randomization method with a block size of 4. An independent random number generation program generates the true / false status code for each stimulation before each treatment. The code is directly written into the switching unit control register, and neither the operator nor the subject can read the code content. When the code corresponds to the false stimulation mode, the switching unit disconnects the input signal of the power amplifier unit from the ground, completely shutting down the ultrasound output channel. However, the external characteristics such as the flashing indicator light on the front panel, the operation of the internal cooling fan, and the buzzer prompt sound are completely consistent with the true stimulation mode. The blind method can be verified by recording the subjective judgments of the operator and the subject after each treatment and statistically analyzing the difference between the judgment accuracy rate and the random probability of 50%. The block randomization method is implemented as follows: every four treatments are divided into blocks, and within each block, the order of two real stimuli and two sham stimuli is randomly arranged to ensure that the number of real and sham stimuli is strictly equal in any four consecutive treatments, avoiding excessive concentration of real or sham stimuli in long sequences. An independent random number generation program uses a cryptographically secure pseudo-random number generator. The seed value is taken from the date and timestamp of the treatment day and is unpredictable. After the code is written into the control register, even equipment maintenance personnel cannot read the current code content from the external interface. In sham stimulation mode, the input signal of the power amplifier unit is grounded through an analog switch. When the analog switch is open, the input signal passes normally; when it is closed, the input terminal is short-circuited to ground. The switch control signal is generated by the switching unit according to the code. No audible relay action sound is generated during the switching process to ensure that the operator and the subject cannot distinguish it by sound. Blind verification is carried out uniformly after all subjects have completed treatment. Each judgment of each operator and subject is summarized, the overall judgment accuracy is calculated, and the chi-square test is used to compare the difference between the accuracy and the 50% random probability.

[0022] The communication interface unit provides a touch interaction signal transmission channel with the display screen 5 and a bidirectional data transmission channel with the EEG monitoring module 9. The communication interface unit integrates an Ethernet interface, a USB interface, and an isolated serial interface. The connection with the display screen 5 adopts LVDS differential signal transmission, which supports 1080P resolution image display and touch coordinate feedback. The bidirectional data transmission with the EEG monitoring module 9 adopts an isolated CAN bus with a transmission rate of 1Mbps and an isolation voltage of 2500V to ensure electrical safety isolation between the EEG acquisition front end and the main control unit. The communication interface unit also reserves WiFi and Bluetooth module interfaces, which can be expanded to realize wireless data transmission and remote monitoring functions.

[0023] The metal shielded enclosure is made of bent and welded aluminum alloy sheet, with conductive foam attached to the inner wall. Each interface is equipped with an electromagnetic compatibility shielding pad, which can effectively suppress the influence of external electromagnetic interference on the internal circuit and prevent the internal high-frequency signals from radiating outward and interfering with other medical equipment. The modular plug-in structure allows the signal generation unit, power amplification unit, control unit and communication interface unit to be installed on independent circuit boards. Each circuit board is plugged into the motherboard through a standard backplane connector, which facilitates single-board debugging, fault location and quick replacement. The power indicator on the front panel is always green after the power is turned on, the running status indicator flashes green when the output is normal, the true / false stimulation mode indicator shows yellow when there is true stimulation and blue when there is false stimulation, and the buzzer sound hole emits a prompt tone of different frequencies and rhythms when the treatment starts, ends and alarms. The direct digital frequency synthesizer uses a high-precision temperature-compensated crystal oscillator as the clock source. It generates a sine wave digital sequence of the required frequency through a phase accumulator and a waveform lookup table, and then converts it into an analog signal through a digital-to-analog converter. The frequency range of 250-500kHz covers the optimal penetration window for transcranial ultrasound stimulation. The 250kHz low-frequency end has a longer wavelength and stronger diffraction ability, which is suitable for stimulation of the temporal region of adults with thicker skulls. The 500kHz high-frequency end has a shorter wavelength, smaller focal spot, and higher spatial resolution, which is suitable for children or areas with thinner skulls. The fine adjustment capability of 1Hz frequency resolution allows the operator to accurately select the optimal working frequency according to the target depth and skull thickness. The programmable design of pulse repetition frequency and working cycle allows the output of pulsed ultrasound stimulation sequences. By adjusting the pulse interval and duty cycle, the average output power can be effectively controlled, ensuring the stimulation effect while avoiding the accumulation of tissue thermal effects. The linear power amplifier uses a high-slew rate operational amplifier with a power supply voltage of ±48V, a maximum output power of 50W, and a bandwidth covering the range of 100kHz to 1MHz. It can amplify sine wave signals with frequencies of 250-500kHz without distortion. The output stage of the power amplifier unit adopts a push-pull Class AB amplification structure, which balances efficiency and linearity and reduces the impact of harmonic distortion on the ultrasonic output waveform. The output power monitoring circuit converts the RF output signal into DC voltage through a precision detector. After analog-to-digital conversion, it is sent to the control unit for digital comparison. The preset safety threshold is set to 80% of the maximum allowable output power. When the detected value exceeds the threshold, the control unit issues a limiting command within 50 milliseconds to reduce the power amplifier gain to a safe range, realizing dual power protection in hardware and software. The control unit uses a 32-bit microprocessor based on the ARM Cortex-M7 core with a main frequency of 480MHz and a built-in floating-point unit, capable of executing complex digital signal processing algorithms in real time. The 50Hz power frequency notch filter of the closed-loop control algorithm uses an adaptive notch filter, which can automatically track small fluctuations in the power grid frequency to ensure that the notch depth exceeds 60dB. The 0.5-70Hz bandpass filter uses a fourth-order Butterworth filter, which has a flat frequency response in the passband and can completely preserve the effective frequency components of the EEG signal. The power spectral density of each frequency band is calculated using a 512-point fast Fourier transform, with a frequency resolution of approximately 0.98Hz, and is updated every 250 milliseconds. The spike index is calculated by detecting transient spikes in the EEG signal that exceed 5 standard deviations of background activity. The baseline value is taken from the average level of the resting-state EEG 30 seconds before the stimulation begins. When an EEG feature that meets the abnormal criteria is detected, the control unit prioritizes the execution of protective actions, with a response delay of no more than 100 milliseconds. The alarm indication uses a rapidly flashing red indicator light on the front panel combined with an intermittent buzzer to ensure that the operator can detect it in time.

[0024] EEG monitoring module 9: The EEG monitoring module 9 is used to synchronously acquire and preprocess the subject's scalp EEG activity signals, providing real-time EEG data for closed-loop safety control. The EEG monitoring module 9 adopts an independent metal shielded chassis, and the internal circuit is electrically isolated from the ultrasonic neuromodulation host module 8 through optocoupler to prevent high-frequency interference from ultrasonic excitation signals from entering the EEG acquisition circuit.

[0025] The independent metal shielded chassis of the EEG monitoring module 9 is physically separated from the chassis of the ultrasound neuromodulation host module 8. The two are connected only by optical fiber or optocoupler data cable, with no common ground loop. The optocoupler isolation uses a high-speed digital isolation chip with an isolation voltage of 5000V and a data rate of 10Mbps. While transmitting digital EEG data, it completely blocks the electrical connection between the two modules, fundamentally eliminating the possibility of ultrasound excitation signals entering the EEG acquisition circuit through crosstalk of the ground wire or power line. The front panel of the EEG monitoring module 9 is equipped with a lead connection status indicator. When the contact impedance between any lead electrode and the scalp exceeds 10kΩ, the corresponding indicator light turns red, reminding the operator to readjust the electrode position.

[0026] The EEG monitoring module 9 includes the following components: The EEG electrode interface box, located on the front panel of the module, provides multiple standard EEG electrode interface terminals, supporting 16-lead or 32-lead scalp electrode input. The interface terminals adopt a pin-type quick-connect design, which facilitates the quick connection and disconnection of electrode lead wires. Each input terminal is equipped with an electrostatic discharge protection diode to prevent electrostatic damage to the internal circuit. The EEG electrode interface box features a 1.5mm standard pin pitch quick-connect terminal, compatible with internationally recognized EEG electrode lead connectors. Its 16-lead configuration covers the international 10-20 system's Fp1, Fp2, F3, F4, C3, C4, P3, P4, O1, O2, F7, F8, T3, T4, T5, and T6 leads, enabling comprehensive monitoring of the entire brain region. The electrostatic discharge protection diode has a response time of less than 1 nanosecond, a clamping voltage of ±15V, and meets the ±8kV contact discharge and ±15kV air discharge protection levels of IEC61000-4-2 standards, effectively protecting subsequent amplification circuits from damage caused by static electricity during operation.

[0027] The signal amplifier is connected to the output of the EEG electrode interface box to perform primary differential amplification on the weak EEG signals collected from the scalp electrodes. The signal amplifier is an instrumentation amplifier with a common-mode rejection ratio greater than 110dB, an input impedance greater than 100MΩ, and an input noise less than 0.5μV peak-to-peak value, which can effectively suppress common-mode interference and extract microvolt-level EEG signals. The instrumentation amplifier uses TI's INA128 or equivalent devices. Its input terminal adopts bipolar super-beta transistor technology to achieve high input impedance and extremely low input bias current. The common-mode rejection ratio of 110dB means that the suppression capability of 50Hz power frequency common-mode interference is more than 300,000 times. Even if there is a strong power frequency electric field in the environment, the residual power frequency interference at the output terminal is much smaller than the amplitude of the EEG signal. The input noise peak-to-peak value of 0.5μV is measured in the 0.5-70Hz passband, which is much lower than the typical EEG signal amplitude of 10-100μV. This ensures that the amplifier's own noise will not mask the weak EEG characteristic waves. The gain of the signal amplifier is programmable and adjustable via a digital potentiometer, with an adjustment range of 100-10000 times to adapt to individual differences in the intensity of EEG signals of different subjects.

[0028] The bandpass filter is connected to the output of the signal amplifier and is used to remove power frequency interference and high and low frequency noise from the amplified signal. The bandpass filter is composed of a high-pass filter and a low-pass filter cascaded together. The high-pass filter has a cutoff frequency of 0.5Hz and is used to filter out DC drift components such as electrode polarization potential. The low-pass filter has a cutoff frequency of 70Hz and is used to filter out high frequency electromyography interference. A separate 50Hz notch filter is also provided to eliminate power frequency grid coupling interference. The high-pass filter uses a second-order Sallen-Key topology with a cutoff frequency of 0.5Hz and attenuation of over 40dB at 0.1Hz, effectively filtering out the slow DC drift potential generated by electrode contact with skin and preventing amplifier output saturation. The low-pass filter uses a fourth-order Butterworth topology with a cutoff frequency of 70Hz and attenuation of over 30dB at 100Hz, significantly suppressing high-frequency electromyographic interference generated by frontalis and temporalis muscle activity. The 50Hz notch filter uses a dual-T active notch topology with a quality factor Q set to 10, a notch depth of over 50dB, and a notch bandwidth of approximately 5Hz, effectively eliminating power frequency interference without excessively damaging EEG frequency components near 50Hz. The passband gain of the entire bandpass filter link is 1, without introducing additional amplification or attenuation.

[0029] The analog-to-digital converter (ADC) is connected to the output of the bandpass filter. It uses a 24-bit high-precision ADC chip with a sampling rate set to 500Hz. It converts the filtered analog EEG signal into a digital signal. The digital output of the ADC is isolated by optocoupler and then sent to the control unit of the ultrasound neuromodulation host module 8 via the data bus. The 24-bit analog-to-digital converter (ADC) uses the ADS1299 or an equivalent bioelectric-specific ADC. It integrates a programmable gain amplifier and a right leg drive circuit, with a signal-to-noise ratio of 120dB, an effective resolution of 21 bits, and a 500Hz sampling rate, which is more than 7 times that of the highest frequency component of the EEG signal (70Hz). This satisfies the Nyquist sampling theorem and provides sufficient anti-aliasing margin without generating excessive data traffic. Each channel's sampled data is encapsulated as a 24-bit signed integer, and the 16 channels generate 19,200 bytes of data per second. The data is transmitted to the control unit via an isolated CAN bus or SPI bus, with a transmission bandwidth utilization rate of less than 20%, leaving sufficient margin to ensure no data loss. The ADC has a built-in offset calibration function that automatically performs zero-input calibration before each treatment to eliminate DC offset differences between channels.

[0030] The base 1 is welded from high-strength aluminum alloy profiles and powder-coated, providing excellent load-bearing capacity and corrosion resistance. Four casters 2 are installed at the four corners of the lower end of the base 1, allowing the entire machine to move flexibly within the treatment room or laboratory, facilitating switching between different examination beds or treatment positions. The two side panels 3 and the top panel 4 together form a gantry-style frame structure. This structural design allows the functional modules to be arranged in a hierarchical and symmetrical manner, resulting in a low center of gravity and good stability. The display screen 5 is installed above the top panel 4, allowing the operator to stand and look directly at the screen, reducing fatigue caused by prolonged head-down operation. The energy module 6 is responsible for providing the main power supply and energy distribution for the entire machine. The two trays 7 are horizontally pulled out and installed between the two side panels, facilitating the maintenance and replacement of the ultrasound neuromodulation host module 8 and the EEG monitoring module 9. The ultrasound neuromodulation host module 8 is used to generate low-frequency, low-power ultrasound excitation signals, while the EEG monitoring module 9 is used to simultaneously collect the subject's brain activity signals. Together, they achieve an integrated stimulation and monitoring working mode.

[0031] The positioning frame assembly 10 is configured as a mechanical adjustment structure with at least two degrees of freedom for positioning the ultrasonic transducer at a target location on the subject's head. The positioning frame assembly 10 is the core mechanical component in the entire device used to fix the subject's head and guide the transducer positioning. The positioning frame assembly 10 achieves precise positioning of any target point on the subject's head through mechanical adjustment with three degrees of freedom: circumferential rotation around the vertical axis of the head, arc translation along the sagittal plane, and radial extension and retraction feed along the target point. All adjustments are made by manual mechanical locking, without relying on motor drive, making the structure reliable, cost-controllable, and the positioning will not be lost in the event of power failure. The main structure of the positioning frame assembly 10 is made of aluminum alloy and engineering plastics, and the total weight is controlled within 500 grams, so it will not put too much burden on the subject's head when worn.

[0032] The focusing transducer assembly 11 includes a focused ultrasonic transducer with an operating frequency of less than 1 MHz; The focusing transducer 11 is used to convert the excitation electrical signal generated by the ultrasound neuromodulation host module 8 into focused ultrasound waves and apply them to the target brain region below the skull of the subject. The working frequency of the focused ultrasound transducer is 250-500kHz, which is in the low-frequency ultrasound range. It has good skull penetration ability and can effectively transmit sound energy to deep target areas such as the amygdala and anterior cingulate cortex. The focused ultrasound transducer adopts a concave self-focusing method, which uses the geometric concave shape of the transducer crystal itself to achieve physical focusing of the sound beam. It does not require a complex electronic phase control array, has a compact structure and high reliability. The focal depth can be adjusted by replacing the crystal with different radii of curvature or adjusting the excitation frequency characteristics. The adjustment range is 1cm to 5cm to adapt to individual differences in skull thickness and target depth of different subjects.

[0033] The EEG monitoring module 9 is electrically connected to the ultrasound neuromodulation host module 8, and the ultrasound neuromodulation host module 8 is configured to automatically adjust the ultrasound output parameters according to the real-time EEG signals collected by the EEG monitoring module 9. The EEG monitoring module 9 and the ultrasound neuromodulation host module 8 are connected via a high-speed digital isolation bus to achieve low-latency transmission of real-time EEG data. After receiving the EEG data, the control unit of the ultrasound neuromodulation host module 8 runs a closed-loop control algorithm to complete the entire process of signal analysis, abnormal judgment and execution of protective actions within 100 milliseconds. When the EEG signal is normal, the control unit maintains the currently set ultrasound output parameters unchanged. When abnormal EEG features are detected, the control unit automatically performs parameter adjustment. The adjustment methods include gradually reducing the output power, shortening the stimulation duration or completely pausing the output. The adjustment process is smooth and will not cause discomfort caused by sudden output changes.

[0034] All casters 2 are equipped with brake pedals; the display screen 5 is a touch screen, and its back is connected to the top plate 4 via an adjustable bracket. The swivel wheels 2 are medical-grade silent swivel wheels with polyurethane surfaces, ensuring quiet movement without damaging the ground. The brake pedal features a single-foot design; pressing it locks the wheel's rolling and rotation, while lifting it unlocks it, making operation simple and intuitive. The pedal surface has anti-slip textures. The display screen 5 is a capacitive touchscreen supporting ten-point touch, covered with a medical-grade antibacterial glass panel. The adjustable angle bracket's tilt angle adjustment range is -5° to +60°, accommodating the viewing angle of operators of different heights. A damping adjustment knob is located at the bracket's pivot point, allowing adjustment of the pivot's tension according to the screen's weight.

[0035] Energy module 6 includes a rechargeable battery and a power management circuit, which has overvoltage and overcurrent protection units. The rechargeable battery uses a lithium iron phosphate battery pack with a nominal voltage of 48V and a capacity of 20Ah. When fully charged, it can provide more than 4 hours of continuous operation for the entire machine. The battery pack has a built-in battery management system that monitors the voltage and temperature of each cell in real time. When overcharging, over-discharging, or abnormal temperature is detected, the charging and discharging circuit is automatically cut off. The power management circuit converts the battery voltage into different voltage levels required by each module, including ±48V for the power amplifier unit, 12V for the control unit and communication interface, 5V for the EEG monitoring module, and 3.3V for the digital logic circuit. The overvoltage protection unit has an operating threshold of 120% of each output voltage, and the overcurrent protection unit has an operating threshold of 150% of the rated current of each voltage channel. The protection response time is less than 10 microseconds.

[0036] The EEG monitoring module 9 includes a signal amplifier, a bandpass filter, and an analog-to-digital converter connected in sequence; the ultrasound neuromodulation host module 8 automatically reduces or pauses ultrasound output when epileptiform discharges are detected in the EEG signal. The signal amplifier amplifies the weak EEG signals collected from the scalp electrodes, the bandpass filter removes power frequency interference and high and low frequency noise, and the analog-to-digital converter converts the analog signal into a digital signal for processing by the host computer. The automatic detection of epileptiform discharges is based on a multi-feature joint judgment algorithm. In addition to the spike index and the alpha band power drop as the two main judgment criteria, the kurtosis and skewness characteristics of the EEG signal are also used as auxiliary references. When any two of the three features trigger abnormalities at the same time, the system confirms the detection of epileptiform discharges and executes protective actions. This multi-feature joint judgment method effectively reduces unnecessary treatment interruptions caused by false triggering of single features.

[0037] The focusing transducer assembly 11 includes a mounting base 1101 mounted on the surface of the side plate 3. A winding rod 1102 is rotatably mounted on one side of the mounting base 1101, and a hanging rod 1103 is fixed on the surface of the winding rod 1102. A servo motor 1104, which is connected to the winding rod 1102, is mounted on the other side of the mounting base 1101. A transmission line 1105 is wound around the surface of the winding rod 1102. An ultrasonic electrode head 1106 is fixed to the extension of the transmission line 1105, and a focusing patch 1107 is attached to the lower end face of the ultrasonic electrode head 1106. The focusing patch 1107 is a concave self-focusing piezoelectric ceramic wafer with a working frequency range of 250-500kHz and an adjustable focal depth ranging from 1cm to 5cm. The transmission line 1105 is a radio frequency coaxial shielded wire with a flexible corrugated sheath. An emergency stop button is also mounted on the surface of the side plate 3. The emergency stop button is connected in series in the power supply circuit between the energy module 6 and the ultrasonic neuromodulation host module 8. Mounting base 1101 is fixed to the side of side plate 3 by four M8 bolts, providing rigid support for the entire winding mechanism. The winding rod 1102 is a 20mm diameter stainless steel rod, with both ends rotatably connected to mounting base 1101 via deep groove ball bearings. The hanging rod 1103 extends axially along the winding rod 1102 and has multiple annular grooves with a groove spacing of 5mm, used to arrange the transmission lines 1105 in layers to prevent cable tangling. The servo motor 1104 is a DC brushless servo motor with encoder feedback, rated... With a torque of 0.5 Nm and a speed control accuracy of ±1 rpm, when treatment is required, the servo motor 1104 drives the retractor 1102 to extend the transmission line 1105. The operator can then pull out the ultrasonic electrode head 1106 to the desired length and fix it to the front end of the I-shaped slide 1012 on the positioning frame assembly 10. When treatment is finished or storage is required, the servo motor 1104 rotates in the opposite direction to automatically retract the transmission line 1105, keeping the cable neat and orderly. The focusing patch 1107 is made of PZT-4 piezoelectric ceramic material. With a Curie temperature of 320°C and a high mechanical quality factor, it is suitable for high-power ultrasonic applications. The concave self-focusing curvature radius series includes five specifications: 30mm, 40mm, 50mm, 60mm, and 70mm, corresponding to focal depths of 1cm, 2cm, 3cm, 4cm, and 5cm respectively. The 1105 transmission line's RF coaxial shielded cable has an inner conductor of silver-plated copper wire and an outer shielding layer of tin-plated copper wire braided mesh. It has a characteristic impedance of 50Ω and attenuation of less than 0.2dB / m at 500kHz. It also features a flexible corrugated tube. The sheath is made of stainless steel corrugated tubing with an outer diameter of 8mm, a minimum bending radius of 25mm, and a bending resistance of over 100,000 cycles. The emergency stop button is a red mushroom-shaped button with a diameter of 40mm and is clearly marked. In an emergency, the operator or accompanying person can quickly press it with their palm to instantly cut off the power supply to the ultrasonic neuromodulation host module 8, causing the ultrasonic output to stop immediately. The emergency stop button uses normally closed contacts connected in series in the power supply circuit. Even if the button itself is damaged due to a fault and the circuit is disconnected, the power supply circuit will be automatically cut off, which complies with the fail-safe principle.

[0038] A positioning frame for transcranial ultrasound stimulation, comprising: The annular groove 1004 is circumferentially rotatable. The first arc-shaped frame 1007 can slide along the annular groove 1004 and has arc-shaped translational freedom. The second arc frame 1011 is connected to the first arc frame 1007, and its interior is provided with a radially retractable I-shaped slide 1012. Locking mechanism, used to lock the position of each degree of freedom; The annular slide 1004 is made of aluminum alloy and CNC machined. It has an inner diameter of 280mm, an outer diameter of 320mm, and a width of 15mm. The inner surface of the slide is hard anodized with a surface hardness of HV400, providing good wear resistance. The annular slide 1004 provides a complete circular guide rail with a circumferential rotation range of 360°, allowing the ultrasonic transducer to be positioned at any position on the head. The first arc frame 1007 has an arc radius of 120mm and an arc angle of 120°, matching the contour curve of the top of the skull. The second arc frame 1011 has a radial extension stroke of 60mm. Together with the I-shaped slide 1012, it can gradually push the focusing patch from 50mm away from the scalp to a position close to the scalp. The locking mechanism uses a combination of hand-tightened bolts and clamping blocks. The locking force is manually controlled by the operator and does not rely on tools. After locking, the positional stability of each degree of freedom does not exceed 0.5mm under a 10N external force.

[0039] It also includes two headgear frames 1001, with an elastic band 1002 installed between the two headgear frames 1001. The elastic band 1002 is used to adjust the head circumference adaptation range, which is 45-65cm. Multiple support rods 1003 are installed on the upper surface of each of the two headgear frames 1001. The support rods 1003 are telescopic structures, and annular grooves 1004 are installed on the upper surface of the multiple support rods 1003. The two headgear frames 1001 are inverted U-shaped structures, injection molded from medical-grade ABS engineering plastic, with a 5mm thick medical silicone pad lining. They are soft and comfortable to wear and will not cause skin allergies. The elastic band 1002 is made of 30mm wide high-elasticity fabric with a moderate elasticity coefficient. The adjustment range covers a head circumference of 45-65cm, accommodating subjects of different ages from children to adults. There are four support rods 1003, symmetrically distributed. Each support rod consists of an inner tube, an outer tube, and a locking knob. The telescopic adjustment range is 30-80mm. The annular groove 1004 can support the subject's head at different heights to accommodate different head sizes.

[0040] A slider 1005 is slidably sleeved in the inner cavity of the annular groove 1004. A sliding seat 1006 is fixed on the upper end face of the slider 1005. A first arc-shaped frame 1007 is fixed between the two sliding seats 1006. A threaded hole is opened on the side wall of the annular groove 1004. A locking bolt is connected in the threaded hole. The end of the locking bolt abuts against the surface of the slider 1005 to lock the position of the slider 1005. The slider 1005 is made of polytetrafluoroethylene and forms a sliding fit with the inner cavity of the annular groove 1004. The coefficient of friction is 0.1, and the sliding is light and smooth. The sliding seat 1006 is fixed to the slider 1005 by four M4 screws. The material is aluminum alloy and the upper end surface is machined with an arc-shaped contact surface to fit with the lower end surface of the first arc-shaped frame 1007. The locking bolt is an M6 stainless steel hand-tightening bolt with knurled head for easy hand operation. The end is embedded with a brass pad. The contact between the pad and the surface of the slider 1005 will not cause scratches. The locking torque of 0.5 Nm is sufficient to generate enough friction to lock the slider position.

[0041] The upper end face of the first arc-shaped frame 1007 is movably connected to the upper slide plate 1008. The inner cavity of the upper slide plate 1008 is threadedly connected to the first hand-tightening screw 1009, and the lower end face of the first hand-tightening screw 1009 is rotatably mounted with the lower clamping plate 1010. The upper slide plate 1008 is fixed to the two sides respectively with the second arc-shaped frame 1011. The I-shaped slide block 1012 is threadedly connected to the second hand-tightening screw 1013, and the lower end face of the second hand-tightening screw 1013 is rotatably mounted with the pressure plate 1014. The lower end face of the upper sliding plate 1008 is machined with an arc-shaped groove that matches the upper end face of the first arc-shaped frame 1007. The movable connection between the two allows the upper sliding plate to slide and adjust its position back and forth along the upper end face of the first arc-shaped frame. The adjustment range covers the entire arc length of the first arc-shaped frame 1007. When the upper sliding plate 1008 reaches the target position, the first hand-tightening screw 1009 is tightened, causing the lower clamping plate 1010 to press upward against the lower end face of the first arc-shaped frame 1007. The position is locked by the friction of the upper and lower clamping. The two second arc-shaped frames 1011 extend forward and backward from both sides of the upper sliding plate 1008, respectively. The radius of the I-shaped slide is the same as that of the first arc frame, and the extension angle is 60° for each. The I-shaped slide block 1012 is an I-shaped cross-section slider that cooperates with the T-slot inside the second arc frame 1011 and can slide freely in the radial direction. When the second hand-tightening screw 1013 is screwed down, it pushes the pressure plate 1014 to press against the inner wall of the second arc frame 1011. The friction force fixes the I-shaped slide block in the required radial position. The heads of the first hand-tightening screw 1009 and the second hand-tightening screw 1013 are provided with torque indicator marks. When the marks are aligned, it indicates that the locking torque has reached the design value, avoiding over-tightening that damages the parts or under-tightening that causes positioning deviation.

[0042] In this embodiment, a method for switching between true and false stimulation for transcranial ultrasound stimulation, applied to the device of claim 1, includes: The real / sham stimulation switching unit integrated within the ultrasound neuromodulation host module 8 generates a random coding sequence to determine whether the current treatment is a real stimulation mode or a sham stimulation mode. The random coding sequence is generated using a block randomization method. If it is a false stimulation mode, turn off the ultrasonic energy output, while keeping the appearance and sound prompts of the ultrasonic electrode head 1106 consistent with the real stimulation mode. The specific operation steps of the real / sham stimulation switching method are as follows: Before each treatment begins, the real / sham stimulation switching unit obtains a coded value from an independent random number generation program. The coded value is 0 or 1, where 0 represents the real stimulation mode and 1 represents the sham stimulation mode. The block randomization method ensures that every four consecutive treatments contain exactly two real stimulations and two sham stimulations, avoiding the situation where multiple consecutive treatments use the same mode. The coded value remains unchanged throughout the treatment and automatically expires after the treatment ends. A new code is generated for the next treatment. If the current code corresponds to the sham stimulation mode, the switching unit grounds the input signal of the power amplification unit at the moment the treatment begins, so that no ultrasonic energy is output to the ultrasonic electrode head 1106 during the entire treatment process. However, all external manifestations of the device—including the normal flashing of the indicator lights on the front panel and internal... The operating sound of the cooling fan and the buzzer's prompt at the start of treatment were exactly the same as the real stimulation mode. The ultrasonic electrode head 1106 maintained a normal operating temperature simulation in the sham stimulation mode, which was achieved by a miniature heating resistor attached to the inner wall of the electrode head with a heating power of 0.5W, keeping the surface temperature of the electrode head at 35-37°C, consistent with the operating temperature of the ultrasonic transducer during real stimulation. This prevented the subject from identifying the stimulation type through temperature perception. After the treatment, the operator and the subject recorded their judgment of the treatment mode through an electronic questionnaire. After all subjects completed the treatment, the judgment data were summarized, and the judgment accuracy rate of the operator and the subject was calculated. If the judgment accuracy rate was not statistically significantly different from 50%, i.e., the P value was greater than 0.05, it proved that the blinding method was effective and the reliability of the experimental results was guaranteed.

[0043] In this embodiment, the working principle of the low-frequency, low-power focused ultrasound transcranial stimulation device is as follows: Before starting the device, the operator moves the entire unit to the treatment position using the casters 2 installed around the lower end face of the base 1. The operator then presses the brake pedal on the casters 2 to lock the wheels, thus fixing the base 1 and the gantry frame formed by the side plates 3 and the top plate 4. After power is connected, the rechargeable battery and power management circuit in the energy module 6 begin supplying power to each electrical module. The power management circuit monitors voltage and current in real time. In case of overvoltage or overcurrent abnormalities, the overvoltage and overcurrent protection unit automatically cuts off the output to ensure electrical safety. The operator sets the stimulation parameters for this treatment, including frequency, pulse repetition frequency, working cycle, duration of action, and target coordinates, using the touch screen 5 mounted on the adjustable bracket above the top plate 4, and retrieves the subject's... In the treatment preparation phase, the positioning frame component 10 is worn on the subject's head. Two headgear frames 1001 are placed on the left and right sides of the head, respectively. The elastic band 1002 connecting the two headgear frames 1001 automatically adjusts to the head circumference, with a range of 45-65cm, ensuring a stable and comfortable fit. Multiple retractable support rods 1003 installed on the upper surface of the headgear frame 1001 support the annular groove 1004 above the head. The height of the annular groove 1004 is changed by adjusting the extension length of the support rods 1003. After the slider 1005 slides circumferentially along the inner cavity of the annular groove 1004 to the target angle, the locking bolt in the threaded hole on the side wall is tightened, so that the end of the locking bolt abuts against the surface of the slider 1005. The slider 1005 is locked in place, and the sliding seat 1006 fixed to the upper surface of the slider 1005 rotates synchronously into position with the slider. The first arc-shaped frame 1007 installed between the two sliding seats 1006 completes circumferential positioning. The upper slide plate 1008, which is movably connected to the upper surface of the first arc-shaped frame 1007, slides back and forth along the arc-shaped face. After reaching the preset position, the first hand-tightening screw 1009 is tightened, which pushes the lower clamping plate 1010, which is rotated and installed on the lower surface, to press upward against the lower surface of the first arc-shaped frame 1007 to achieve locking, thus completing the arc-shaped translational degree of freedom positioning. The I-shaped slides 1012 fixed on the two second arc-shaped frames 1011 on both sides of the upper slide plate 1008 slide radially, so that the front end of the I-shaped slide is close to the corresponding position of the target point on the subject's scalp. Tightening the second hand-tightening screw 1013 pushes the pressure plate 1014, which is rotated and mounted on the lower end face, to press against the inner wall of the second arc-shaped frame 1011 to complete the fixation and complete the radial extension and retraction degree of freedom positioning. This achieves precise mechanical target point positioning with three degrees of freedom, with a positioning error of no more than ±1mm. After positioning, the ultrasonic neuromodulation host module 8 sends a control signal to drive the servo motor 1104 mounted on the mounting base 1101 on the side plate 3 to rotate, which drives the winding rod 1102 to rotate and release the transmission line 1105 wound on it. The hanging rod 1103 fixed to the surface of the winding rod 1102 releases the transmission line 1105 in layers and in an orderly manner through its annular groove. The winding speed is 0.1 meters per second, and the total length of the transmission line 1105 is 1.The operator secures the ultrasonic electrode head 1106, which is fixed to the extension section of the transmission line 1105, to the front end of the I-shaped slide 1012, ensuring that the focusing patch 1107, which is attached to the lower end face of the ultrasonic electrode head 1106, is in close contact with the subject's scalp. The signal generation unit inside the ultrasonic neuromodulation host module 8 uses a direct digital frequency synthesizer to generate a low-frequency, low-power sine wave excitation signal with a frequency of 250-500kHz. After being amplified by a linear power amplifier unit, the signal is transmitted to the ultrasonic electrode head 1106 through the radio frequency coaxial shielded transmission line 1105. The insulating medium between the inner conductor and the outer shielding layer of the transmission line 1105 effectively suppresses electromagnetic interference crosstalk. The externally fitted flexible corrugated sheath protects the cable from bending. The concave self-focusing piezoelectric ceramic wafer of the focusing patch 1107 uses its geometric concave shape to convert electrical energy into acoustic energy and achieve sound beam propagation. The focus depth can be adjusted within the range of 1cm to 5cm by changing patches with different curvature radii or adjusting the excitation frequency characteristics. The ultrasound energy penetrates the skull and focuses on deep target areas such as the amygdala and anterior cingulate cortex. During the treatment, the EEG monitoring module 9 synchronously collects the subject's brain activity signals through scalp electrodes connected to the EEG electrode interface box. The signal amplifier uses an instrumentation amplifier for primary differential amplification with a common-mode rejection ratio greater than 110dB. A bandpass filter removes power frequency interference and high and low frequency noise. The analog-to-digital converter uses a 24-bit high-precision chip to convert the signal into a digital signal at a sampling rate of 500Hz. After optocoupler isolation, the signal is sent to the control unit of the ultrasound neuromodulation host module 8 via a data bus. The control unit, with a microprocessor as its core, runs a closed-loop control algorithm. First, the EEG signal is subjected to 50Hz power frequency notch filtering and 0.The system performs 5-70Hz bandpass filtering preprocessing, then extracts characteristic parameters such as power spectral density, spike index, and kurtosis for each frequency band. These parameters are then compared with preset abnormality criteria. If the spike index exceeds three standard deviations from the baseline value and lasts for more than 100ms, or if the alpha band power drops by more than 50% within one second, the control unit automatically executes protective actions, reducing output power or pausing ultrasound output. Simultaneously, the front panel indicator light flashes and the buzzer sounds an alarm. Treatment resumes automatically or manually after the EEG characteristics return to normal. An emergency stop button mounted on the side panel 3 is connected in series in the power supply circuit between the energy module 6 and the ultrasound neuromodulation host module 8. Using a normally closed contact design, the operator or accompanying person can press the red mushroom-shaped button in an emergency to instantly cut off the host power supply, stopping the ultrasound operation. The process stops immediately, adhering to the fail-safe principle. Before each treatment, the integrated real / sham stimulation switching unit within the ultrasound neuromodulation host module 8 generates a randomized coding sequence using a block randomization method to determine whether the current treatment is a real or sham stimulation mode. The code is directly written into the control register, inaccessible to both the operator and the subject. When the code corresponds to a sham stimulation mode, the switching unit disconnects the power amplifier unit's input signal from ground, completely shutting down the ultrasound output channel. However, external characteristics such as flashing indicator lights on the front panel, running internal cooling fans, and a buzzer sound are maintained to ensure complete consistency with real stimulation, guaranteeing the rigor of the double-blind clinical trial. After treatment, the servo motor 1104 rotates in the reverse direction to rewind the transmission line 1105, and the operator releases the locking mechanisms to remove the positioning frame assembly 10, completing the entire treatment process.

[0044] The present invention provides a detailed description of a low-frequency, low-power focused ultrasound transcranial stimulation device. Specific embodiments have been used to illustrate the principles and implementation methods of the invention. These embodiments are merely illustrative and are intended to aid in understanding the method and core concepts of the invention. It should be noted that those skilled in the art can make various improvements and modifications to the invention without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims.

Claims

1. A low-frequency, low-power focused ultrasound transcranial stimulation device, characterized in that, include: The base (1) has casters (2) installed around the lower end face of the base (1), side plates (3) are fixed on both sides of the upper end face of the base (1), a top plate (4) is fixed between the upper end faces of the two side plates (3), a display screen (5) is installed on the upper end face of the top plate (4), an energy module (6) is installed on the upper end face of the base (1), two trays (7) are installed between the two side plates (3), and an ultrasound neuromodulation host module (8) and an electroencephalogram monitoring module (9) are respectively installed on the upper end faces of the two trays (7). The positioning frame assembly (10) is configured as a mechanical adjustment structure with at least two degrees of freedom for positioning the ultrasonic transducer at a target location on the subject's head; A focused transducer assembly (11) includes a focused ultrasonic transducer with an operating frequency of less than 1 MHz; The EEG monitoring module (9) is electrically connected to the ultrasound neuromodulation host module (8), and the ultrasound neuromodulation host module (8) is configured to automatically adjust the ultrasound output parameters according to the real-time EEG signals collected by the EEG monitoring module (9).

2. The low-frequency, low-power focused ultrasound transcranial stimulation device according to claim 1, characterized in that, Each of the casters (2) is equipped with a brake pedal; the display screen (5) is a touch screen, and its back is connected to the top plate (4) through an adjustable bracket.

3. The low-frequency, low-power focused ultrasound transcranial stimulation device according to claim 1, characterized in that, The energy module (6) includes a rechargeable battery and a power management circuit, the power management circuit having overvoltage and overcurrent protection units.

4. The low-frequency, low-power focused ultrasound transcranial stimulation device according to claim 1, characterized in that, The EEG monitoring module (9) includes a signal amplifier, a bandpass filter and an analog-to-digital converter connected in sequence; the ultrasound neuromodulation host module (8) automatically reduces or pauses ultrasound output when epileptiform discharge is detected in the EEG signal.

5. A positioning frame for transcranial ultrasound stimulation, characterized in that, include: The annular groove (1004) can rotate circumferentially; The first arc-shaped frame (1007) can slide along the annular groove (1004) and has arc-shaped translational freedom; The second arc frame (1011) is connected to the first arc frame (1007), and its interior is provided with a radially extendable I-shaped slide (1012). The locking mechanism is used to lock the position of each degree of freedom.

6. The positioning frame according to claim 5, characterized in that, It also includes two headgear frames (1001), with an elastic band (1002) installed between the two headgear frames (1001). The elastic band (1002) is used to adjust the head circumference adaptation range, which is 45-65cm. Multiple support rods (1003) are installed on the upper surface of each of the two headgear frames (1001). The support rods (1003) are telescopic structures, and the annular grooves (1004) are installed on the upper surface of the multiple support rods (1003).

7. The positioning frame according to claim 5, characterized in that, The annular groove (1004) has a sliding block (1005) slidably sleeved inside. A sliding seat (1006) is fixed on the upper end face of the sliding block (1005). The first arc frame (1007) is fixed between the two sliding seats (1006). A threaded hole is opened on the side wall of the annular groove (1004). A locking bolt is connected in the threaded hole. The end of the locking bolt abuts against the surface of the sliding block (1005) to lock the position of the sliding block (1005).

8. The positioning frame according to claim 5, characterized in that, The upper end face of the first arc-shaped frame (1007) is movably connected to the upper slide plate (1008), the inner cavity of the upper slide plate (1008) is threadedly connected to the first hand-tightening screw (1009), and the lower end face of the first hand-tightening screw (1009) is rotatably mounted with the lower clamping plate (1010). The second arc-shaped frame (1011) is fixed on both sides of the upper slide plate (1008); the inner thread of the I-shaped slide block (1012) is threadedly connected to the second hand-tightening screw (1013), and the lower end face of the second hand-tightening screw (1013) is rotatably mounted with the pressure plate (1014).

9. A method for switching between true and false stimulation in transcranial ultrasound stimulation, applied to the device described in claim 1, characterized in that, include: The real / sham stimulation switching unit integrated inside the ultrasound neuromodulation host module (8) generates a random coding sequence to determine whether the current treatment is a real stimulation mode or a sham stimulation mode. The random coding sequence is generated using a block randomization method. If it is a false stimulation mode, turn off the ultrasonic energy output, while keeping the appearance and sound cues of the ultrasonic electrode head (1106) consistent with the real stimulation mode.

10. A low-frequency, low-power focused ultrasound transcranial stimulation device according to claim 1, characterized in that, The focusing transducer assembly (11) includes a mounting base (1101) mounted on the surface of the side plate (3). A winding rod (1102) is rotatably mounted on one side of the mounting base (1101). A hanging rod (1103) is fixed on the surface of the winding rod (1102). A servo motor (1104) that is connected to the winding rod (1102) is mounted on the other side of the mounting base (1101). A transmission line (1105) is wound on the surface of the winding rod (1102). An ultrasonic electrode head (1106) is fixed on the extension section of the transmission line (1105). Furthermore, a focusing patch (1107) is attached to the lower end face of the ultrasonic electrode head (1106); the focusing patch (1107) is a concave self-focusing piezoelectric ceramic wafer with a working frequency range of 250-500kHz and an adjustable focal depth ranging from 1cm to 5cm; the transmission line (1105) is a radio frequency coaxial shielded line with a flexible corrugated tube sheath on its outside; an emergency stop button is also installed on the surface of the side plate (3), and the emergency stop button is connected in series in the power supply circuit of the energy module (6) and the ultrasonic neuromodulation host module (8).

Images