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Numerical Optimization of Waveguide Structure in an Ultrasound Brain Stimulation System Using the FDTD Method

Ultrasound stimulation is expected to be capable of transcranial deep and local stimulation to the brain, which is difficult to achieve using conventional electromagnetic stimulation. Once an ultrasound transducer is determined, however, its physical characteristics are hard to change. For obtaining the appropriate irradiation properties, we used a computer simulation of our experimental setup to characterize the optimal shape and size of a waveguide attached to the tip of an ultrasound transducer to target a specific brain region. We obtained an optimal waveguide structure to produce the desired intensity distribution. Our next challenge is to test in our physical setup. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.