Reconstructions of Tissue Thermal Properties Together with Perfusion and Thermal Source

Abstract

A robust non-invasive technique for reconstructing the thermal properties of living tissues-thermal conductivity, thermal capacity and thermal diffusivity - and thermal quantities such as thermal source/sink and perfusion for diagnosis, and monitoring and planning thermal treatments such as a high-intensity focused ultrasound (HIFU) and interstitial radio frequency (RF) or microwave electromagnetic coagulation therapy are reported. Internal tissue temperature distributions can be measured using ultrasonic imaging or magnetic resonance imaging. When performing a reconstruction after stopping heating and perfusion, only the thermal properties are reconstructed. However, because the region of interest may include thermal source and the perfusion cannot always be stopped, by increasing the independent temperature field data, the thermal source and perfusion can also be reconstructed. The feasibilities of the reconstructions of thermal source and perfusion are respectively verified by simulations. Although the increase in the number of equations leads to unstable results for the reconstruction of perfusion, our developed regulation is effective for stabilizing the reconstruction.