Modelling of different types of applicators used for microwave hyperthermia based on FDTD method

The authors have developed a two dimensional model based on the finite difference time domain (FDTD) method for the study of interstitial and intracavitary applicators. This model takes into account the different lossy media surrounding the antenna (water, plastic catheter, metallic reflector...) in order to optimise the applicator at heating and radiometric frequencies: computation of the return losses (reflection coefficient) and of the power deposition gives the performances of the applicator and are very useful for thermal dosimetry based on the resolution of the bioheat equation. The theoretical results obtained with the FDTD method have been compared to experimental measurements.