The Development Of Low-intensity Pulsed Ultrasound Neurostimulation System And Application Research Of Inflammation Regulation

Low-intensity pulsed ultrasound(LIPUS)refers to ultrasonic waves with an intensity below 3W/cm~2 and transmitted in the form of pulses,which has the advantages of high resolution,strong penetration,and non-invasiveness.As a novel neuromodulation technique,low-intensity pulsed ultrasound has good targeting and low damage.However,the current ultrasonic systems for neuromodulation have the defects of limited parameter adjustment and output energy,which is difficult to meet the needs of a wide range of low-intensity pulsed ultrasound experiments.In order to solve this problem,this paper developed a low-intensity pulsed ultrasound neurostimulation system with multi-parameter adjustable and a wide range of energy output and validates the system performance by inflammation modulation experiments.First,a low-intensity pulsed ultrasound neurostimulation system was developed,and then an output test platform was built based on it to test the system output energy and feasibility.Under the control of the FPGA,the signal generation module in the system generates a digital sine wave based on the DDS principle,adjusts the ultrasonic parameters by configuring the digital-to-analog conversion chip,and controls the output of the original sine waveform through the amplitude-control module;in the power amplification module,after the pre-amplification and through power distribution and power synthesis technology,the power amplification of the original sine signal is completed based on the secondary amplification module,so the ultrasonic wave with enough energy is finally generated to drive the ultrasonic transducer.On the basis of the above work,an output test platform was built to test and analyze the ultrasonic intensity and acoustic field generated by the low-intensity pulsed ultrasound neurostimulation system.In addition,the difference in ultrasonic intensity output under different parameters and the influence of collimators and skulls on ultrasonic output were also analyzed.Secondly,a platform for ultrasound biostimulation was built and the data of low-intensity pulsed ultrasound to modulate peripheral inflammation was obtained and statistically analyzed.Two low-intensity pulsed ultrasound spleen modulation methods for different degrees of peripheral inflammation were designed,and the level of inflammatory factors in the spleen of mice was used as an observation index,so the performance of low-intensity pulsed ultrasound neurostimulation system in modulating peripheral inflammation was verified through statistical analysis of the data.Then the mechanism of that low-intensity pulsed ultrasound improving peripheral inflammation through neuromodulation was analyzed.Finally,the data of low-intensity pulsed ultrasound modulating central nervous system inflammation was obtained and statistically analyzed to verify the performance of low-intensity pulsed ultrasound neurostimulation system in modulating central inflammation.A method for central neuroinflammation modulation based on LIPUS was designed,and the level of inflammatory factors in hippocampal tissue and the behavioral data of water maze were used as observational indicators,hence the feasibility of low-intensity pulsed ultrasound neurostimulation system in improving neuroinflammation and induced cognitive dysfunction was revealed through statistical analysis.