Thermal treatment to avoid a surgical procedure involves a variety of energy sources. In several sites, radiofrequency energy is used as a source of thermal treatment. In the course of controlling lesion volume and shape during therapy, a number of sizes and shapes of applicators can be used as well as cooling or power pulsing to control or increase lesion size. Multiple sources are also used with monopolar or sesquipolar radiofrequency power delivery to enlarge the treatment volume. Following extensive in-vitro and in-vivo testing to optimize lesion size with time, power, and device, a simulation was set up to correlate theoretical predictions with experimental results with and without blood flow. A finite element model was applied to simulate the electric field and by using the bioheat equation, a thermal profile over time was established for various device parameters used in the experiments. The damage integral was used to estimate lesion size of irreversible damage. These results were compared to experimental results to verify the model's accuracy in predicting lesion size of both in-vitro and in-vivo experiments.
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