Acoustic characteristics of HIFU using the finite difference time domain method in tissue

The micro robot was controlled by the electromagnetic actuation(EMA) systems for the necrosis of chronic total occlusion(CTO) in blood vessels. But, it was difficult that micro robot went through the lesion because the outside tissues of CTO were hardened by the vascular calcification of the precipitate. Therefore, introduction of high intensity focused ultrasound(HIFU) made that micro robot penetrated the fibrous cap of CTO easy. In this paper, focal distance and pressure of HIFU were estimated by the finite difference time domain(FDTD) method in tissue.