Effect of the antenna slot numbers and position on the performance of microwave ablation

Microwave ablation (MWA) is a type of thermal ablation used for cancer treatment in interventional radiology. To induce localized tissue heating MWA employs electromagnetic waves within the microwave energy spectrum, which is done by the precisely designed antenna. This study substantially emphasizes the design and performance ameliorating of slot (both single and double) antennae and compares the results with conventional monopole antennae in terms of temperature distribution, specific absorption ratio (SAR), and thermal tissue damage rate. The simulation has been done in COMSOL by solving the Bioheat equation along with Maxwell electromagnetic equations using the finite element method. The simulation results reveal that the double-slot antenna has the most accurate and directional heat dissipation for liver tumors as well as the highest tissue damage rate and SAR. The highest SAR was found to be 3500 W/kg and 3350 W/kg at the implant depth of 61 mm and 63 mm for double and single-slot antennae, respectively. In addition, the fastest tissue damage occurred near the upper slot of the double-slot antenna. This study helps to understand the basic design parameters for enhancing single and double-slot antennae performance.