Simulation of control of heat flux with 2D traversable sonication path in high-intensity focused ultrasound treatment

• Published in: Japanese Journal of Applied Physics 2021-12, Vol.60 (12), p.126503
• Main Authors: Iwahashi, Toshihide, Tang, Tianhan, Matsui, Kazuhiro, Fujiwara, Keisuke, Itani, Kazunori, Yoshinaka, Kiyoshi, Azuma, Takashi, Takagi, Shu, Sakuma, Ichiro
• Format: Article
• Language: English
• Subjects: Accumulation; Coagulation; Heat flux; Heat transfer; high-intensity focused ultrasound; thermal ablation; Thermal utilization; Ultrasonic imaging; Ultrasonic processing; ultrasound
• ISSN: 0021-4922; 1347-4065
• DOI: 10.35848/1347-4065/ac30c4

High-intensity focused ultrasound causes thermal coagulation around the focal area in a minimally invasive manner. Multiple sonication is required to treat the target area due to the small size of the focal area. Consequently, the throughput is limited, and several sonication paths have been proposed to improve it. However, a systematic comparison of these paths is lacking. In this study, the effect of the moving focal area was analyzed using a moving heat source model. The effects of moving the heat source and the utilization of thermal accumulation were evaluated for the proposed sonication paths. Controlling multiple foci was effective because the heat flux was concentrated on energy that was focused in the unprocessed area without providing energy to previously processed areas. The multiple foci using thermal accumulation could reduce the treatment time and total input energy by 7.7% and 50%, respectively, compared to methods without thermal accumulation.