Numerical simulation of a method to reduce high cranial pressure in high intensity focused ultrasound for transcranial brain therapy

Transcranial high intensity focused ultrasound (HIFU) may form hot spots with higher acoustic pressure and temperature in the skull, causing damage to the skull and surrounding tissues. This paper optimized the existing cranial high pressure reduction technology with phase regulation based on the time reversal method and proposed the high cranial pressure reduction algorithm based on particle swarm optimization (PSO-SHPRA), which is an algorithm of adding amplitude modulation to excitation signal and using particle swarm optimization (PSO) to optimize the amplitude modulation coefficients in an iterative manner. To verify the effectiveness of the algorithm, we used the Westervelt nonlinear acoustic propagation equation to carry out numericals based on a transcranial ultrasound therapy model. The results show that reducing the high cranial pressure is feasible when focusing the ultrasound on the intracranial target area. This paper could provide references for clinical therapeutic planning during the HIFU transcranial ultrasound therapy.