Temperature Rise in Tissue Mimicking Material During HIFU Procedures

High Intensity Focused Ultrasound (HIFU) has shown considerable promise as a minimally-invasive technique for various therapeutic applications such as tumor ablation and vessel cauterization. The efficacies of these HIFU procedures depend on various operational parameters such as total acoustic power, pulse duration and transducer dimensions. In this study, the effect of total acoustic power on the tissue temperature rise is studied both experimentally and numerically. Experimentally, HIFU ablations, at different acoustic powers, were carried out in a tissue mimicking material embedded with thermocouples. Temperature rise measured from the in-vitro experiments were then validated with the numerical computations. Results show that experimental and numerical temperature rise match accurately. Our numerical model was able to predict the peak temperature rise within ∼12% of the experimental results. Results also show that the tissue temperature rise is linearly proportional to the input acoustic power. For the acoustic power levels considered in this study, the results suggest that acoustic non-linearity does not play a major role on the tumor ablation procedure.