Effects of target temperature on thermal damage during temperature-controlled MWA of liver tumor

Abstract

Microwave ablation (MWA) is one among the cancer treatment techniques applied in clinical treatment. This technique is based on rising the temperature within the tissue and the radiation dose absorbed by the cells. The goal of this study is to improve the accuracy of temperature simulation during temperature-controlled MWA of liver tumor. A two-dimensional numerical model of liver tissue has been built and solved using the Finite Element Method (FEM). The bio-heat equation, the first-order Arrhenius rate equations, and the Maxwell equations are employed to simulate the cancer cells necrosis. For heat control, an input microwave power source was controlled by a proportional-integral-derivative (PID) controller to keep the target tip temperature below the preset temperature value during MWA. The effect of the target tip temperature on the applied input microwave power has been investigated in liver tissue. Further, the thermal damage fraction and the time required for complete necrosis liver cancer are also evaluated. The present results show that the specific absorption rate (SAR) and the temperature distribution are highly influenced by the target tip temperature. Optimal treatment period for total tumor ablation will offers a significant way to reduce damage to the surrounding healthy cells and providing safe use of MWA and without risk.