Simulation of nonlinear Westervelt equation for the investigation of acoustic streaming and nonlinear propagation effects
Journal
Journal of the Acoustical Society of America
Journal Volume
134
Journal Issue
5
Pages
3931-3942
Date Issued
2013
Author(s)
Abstract
This study investigates the influence of blood flow on temperature distribution during high-intensity focused ultrasound (HIFU) ablation of liver tumors. A three-dimensional acoustic-thermal-hydrodynamic coupling model is developed to compute the temperature field in the hepatic cancerous region. The model is based on the nonlinear Westervelt equation, bioheat equations for the perfused tissue and blood flow domains. The nonlinear Navier-Stokes equations are employed to describe the flow in large blood vessels. The effect of acoustic streaming is also taken into account in the present HIFU simulation study. A simulation of the Westervelt equation requires a prohibitively large amount of computer resources. Therefore a sixth-order accurate acoustic scheme in three-point stencil was developed for effectively solving the nonlinear wave equation. Results show that focused ultrasound beam with the peak intensity 2470 W/cm2 can induce acoustic streaming velocities up to 75 cm/s in the vessel with a diameter of 3 mm. The predicted temperature difference for the cases considered with and without acoustic streaming effect is 13.5 °C or 81% on the blood vessel wall for the vein. Tumor necrosis was studied in a region close to major vessels. The theoretical feasibility to safely necrotize the tumors close to major hepatic arteries and veins was shown. ? 2013 Acoustical Society of America.
SDGs
Other Subjects
Acoustic streaming effect; Acoustic streaming velocity; High intensity focused ultrasound; Large blood vessels; Nonlinear propagation effect; Nonlinear wave equation; Temperature differences; Westervelt equation; Acoustic streaming; Blood vessels; Hemodynamics; Navier Stokes equations; Tumors; Ultrasonics; Nonlinear equations; article; blood flow velocity; computer simulation; hepatic artery; high intensity focused ultrasound; human; liver circulation; liver tumor; mathematical computing; necrosis; nonlinear system; pathology; pathophysiology; portal vein; temperature; ultrasound; vascularization; Blood Flow Velocity; Computer Simulation; Hepatic Artery; High-Intensity Focused Ultrasound Ablation; Humans; Liver Circulation; Liver Neoplasms; Necrosis; Nonlinear Dynamics; Numerical Analysis, Computer-Assisted; Portal Vein; Temperature; Ultrasonics
Type
journal article