SIMULATION AND EX VIVO EXPERIMENTAL STUDY OF MICROWAVE ABLATION OF ADRENAL ADENOMA BY COAXIAL SLOT ANTENNA

Abstract

Object: Microwave ablation has been widely used in tumor treatment, and the antenna is a critical component of microwave ablation. We aimed to evaluate a single-slot antenna to generate a small volume ablation zone ([Formula: see text] in adrenal tissue. Methods: A three-dimensional numerical model of the adrenal tissue was built and solved by the Finite Element Method. In the simulation model, the slot antenna was placed between the adrenal gland and fat, and the microwave ablation power and time were adjusted to obtain the target ablation zone. In ex vivo experiments, the length and width of the ablation zone were measured, and the significance of ablation parameters on it was determined using a multi-factorial analysis of variance method. The temperature versus time curves at 3[Formula: see text]mm and 7[Formula: see text]mm from the antenna were plotted to validate the simulation. Results: The simulation results showed that the combination of microwave ablation parameter settings 30[Formula: see text]W/300[Formula: see text]s, 40[Formula: see text]W/180[Formula: see text]s, and 40[Formula: see text]W/300[Formula: see text]s could create ablation zones in the adrenal tissue volumes of [Formula: see text] and [Formula: see text], respectively, with minimal damage (less than [Formula: see text] to the surrounding fat tissue. Both power and heating time significantly affected the length and width of the ablation zone. The temperature rise curves obtained in the simulation and ex vivo experiments were in good agreement. Conclusion: This work shows that utilizing a slot antenna can produce a small volume ablation zone in adrenal tissue for microwave ablation of benign adrenal adenomas.