A Computational Study of Time Reversal Techniques for Ultra-Wideband Microwave Hyperthermia Treatment of Breast Cancer

We present a computational study of the application of time reversal (TR) principles to microwave hyperthermia treatment of breast cancer. A wideband source is excited at the tumor location (the desired focus) in an electromagnetic (EM) simulation based on the finite-difference time-domain (FDTD) method and the transmitted wave is recorded at multiple antenna locations. The FDTD-computed signals are time reversed for transmission into the breast. The same set of FDTD-computed signals is also used in a comparative investigation of a space-time beamforming technique, which has been previously studied for microwave hyperthermia. We discuss the relation between these two approaches, and compare the focusing efficacy and heating selectivity of the TR and beamforming approaches using FDTD EM and thermal simulations with anatomically realistic numerical breast phantoms. Promising results from both methods are obtained.