The modeling of temperature distributions of an interstitial two-tine antenna for hepatic cancer microwave ablation

Abstract

Hepatic cancer can be treated by microwave ablation, a therapy in which the goal is to increase the tissue temperature in order to induce necrosis. For the application of microwave ablation interstitial antenna have been developed with the objective of delivering and focusing energy deposition on the tissue in an effective manner. In this study, microwave ablation analyses using 2.45 GHz Two-Tine (2T) antenna for hepatic cancer tissue. This research is designed for a 2T-Conductor back-choke (2T-CBC) and 2T-Dielectrics Back-choke antenna (2T-DBC) and modeled using finite element method to obtain their heating patterns, compare them and analyze the effects of the back-choke to treat by microwave ablation. A preliminary study was first carried out with regard to the specific absorption rates (SAR) along the 2T antenna insertion depths and the ablation zone (heating pattern and lesion volume) inside the hepatic cancer models with 5 cm-in-diameter tumor. All scenarios were simulated under temperature-controlled mode (90°C) and the initial power was set at 50 W. Based on the preliminary results, the result shows that the maximum SAR and lesion volume is higher than when using a 2T-DBC antenna for microwave ablation (97.31 cm3). The conductor tine and bake-choke of the antenna has effect to heating pattern and lesion volume.