Abstract

Info

Author(s):: CAO Wei; CANG Chen; ZHANG Haoqiang; ZHENG Zheng; School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China

Keywords:: Keywords: ultrasound brain stimulation animal experiment array transducer defocus correction focus manipulation

Abstract:: Abstract: Objective To design an array ultrasonound brain stimulator for animal experiments for solving the problem that a single transducer cannot realize defocus correction and focus manipulation. Methods A 16-channel array transducer was used in the simulator, and each channel had an independent matching circuit and driver. Delay circuit and pulse generation circuit were integrated on FPGA and connected to the control interface of the host computer. Then, delay time was measured with a hydrophone, and the focus was corrected and manipulated according to phase compensation principle. Finally, the sound field distribution was scanned with a hydrophone to assess the focus correction and focus offset. Results The sound field test results showed that the defocus was corrected. Moreover, the focus sound pressure was increased by 23% and the side lobe sound pressure was more than 6 dB lower than the main lobe and the size of the -6 dB focal zone was dx=3 mm, dy=3 mm, dz=14 mm. The focus was manipulated to realize focus offsets from the origin O to the left, right, up and down by 2 mm. Conclusion The proposed array ultrasound brain stimulator has the functions of defocus correction and focus manipulation, and it provides a useful tool for the study on ultrasound brain stimulation.