A 3-D simulation of focused ultrasound propagation for extracorporeal shock wave osteotomy

We have previously proposed a method of cutting bones using high intensity focused ultrasound. The goal of the method is to cut bones in a body without incising skin, but the condition under which bones are cut properly is so sensitive that 1 mm of displacement makes cutting bones fail resulting in necrosis around the focal point. In this paper, we have developed a focused ultrasound propagation simulator in full 3-D. Finite Difference Time Domain method has been implemented to simulate ultrasound wave propagation through multi-class tissues. We have employed Perfectly Matched Layer as an absorbing boundary condition to minimize reflections from the boundary of a simulation domain. A comparison of simulation and experimental results has shown that the simulation results are correlative with actual phenomenon and that the presenting method can be used to predict the conditions under which bones can be cut.