The present study is aimed at predicting liver tumor temperature increase during a high-intensity focused ultrasound (HIFU) thermal ablation using the proposed acoustics-heat-fluid coupling model. The linear Westervelt equation is adopted for modeling the incident finite-amplitude wave propagation. The nonlinear hemodynamic equations are also taken into account in the simulation domain that contains a hepatic tissue domain, where homogenization dominates perfusion, and a vascular domain, where blood convective cooling may be essential in determining the success of HIFU. We also consider the energy equation for the modeling thermal conduction heat transfer. Two heat sinks are dealt with to account for tissue perfusion and forced convection-induced cooling. The effect of acoustic streaming is also included in the current HIFU simulation study. Convective cooling in large blood vessel and acoustic streaming were shown to change the temperature near blood vessel. It was shown that the acoustic streaming effect can change the blood flow distribution in hepatic arterial branches and leads to mass flux redistribution. The effect of acoustic streaming can be used to control blood drug delivery. In the current work the realistic geometry for the blood vessel and liver was reconstructed using the MRI images. The presented results may be further used to construct a surgical planning platform for the non-invasive HIFU (High-Intensity Focal Ultrasound) tumor ablating (or cauterizing) therapy in real liver geometry on the basis of the MRI image.
High-intensity interstitial ultrasound for thermal ablation of focal cancer targets in prostate