Modeling of interstitial applicators used for microwave hyperthermia of bone cancer based on subgridding FDTD method

In this paper, the subgridding finite-difference time-domain (FDTD) method is used to analyze the electromagnetic field distribution of the various kinds of interstitial applicators for treating the bone cancers. The 3-dimension subgridding FDTD program is tested by the radiation of an electric dipole in the free space. The calculating results show that the slot applicator is much better than the simple applicator that has been used in clinic for treating the bone cancer. The slot applicator with an enlarged cap can enhance the top field for heating the boundary tissue. The results of this research are very useful to improve the clinic microwave hyperthermia effect of bone tumors in the future.