Improving SAR Homogeneity in a Layered Spherical Model of Head for Hyperthermia Treatments with RF Phased Array Systems

Homogeneity of power delivery to tumor is a first goal in hyperthermia for cancer treatment. In this study, it has been analyzed together with other indicators of the quality of heating. The benchmark is a stratified spherical model of head containing a small spherical target deeply located in its interior. The head model is illuminated by an array of conformal antennas whose radiation is evaluated in closed form. Preliminarily, the radiation by the elementary antenna is shown equivalent to the radiation by a realistic small-size wire antenna. Heating homogeneity being largely conflicting with the other indicators a trade-off is investigated.