A new coupled model for laser-induced thermal ablation accounting for tissue water vaporization

Abstract

A new model is considered to describe the evolution of tissue temperature and water concentration during a thermal ablation process. The aim of this study is to expand the results obtained in Blauth et. al. 2020, where the tissue water concentration is considered as a known function, experimentally obtained. The model consists of two coupled equations: a parabolic partial differential equation for the temperature $\theta$ and an ordinary differential equation for the water content $w$. The equation for $\theta$ accounts for temperature diffusion, blood perfusion, the heat source provided by the laser applicator and the vaporization effects which act when the temperature approaches 100C. The equation for $w$ accounts for the loss of tissue water that occurs during vaporization. The model equations are solved in a cylindrical domain around the laser applicator and the results are compared with the existing experimental data for porcine liver tissue from H\"ubner et. al. 2017.