Estimation of thermal coagulation region induced by bubble-enhanced ultrasonic heating using numerical simulation

Abstract High-intensity focused ultrasound (HIFU) treatment is a non-invasive method for treating cancer by focusing ultrasound from outside the body on a target region to induce heating and coagulation. However, it has the problem of a long treatment time due to its small focal region. To improve treatment efficiency, the use of cavitation bubbles has been proposed. For the safety and efficacy of the treatment, it is important to estimate the coagulation region before HIFU treatment. In this study, we investigated the estimation of the thermal coagulation region of HIFU treatment by numerical simulation of thermal dose distribution. It was assumed that the ultrasonic absorption increased due to the presence of cavitation bubbles in the region containing cavitation bubbles. As a result, we were able to reproduce the short diameter, long diameter, and the shapes of the coagulation region under several sonication conditions.