Noninvasive control of microwave hyperthermia by retro-focusing.

Phased arrays for hyperthermia application have numerous advantages. They have the ability to be focused onto a desired location, and have a slightly greater depth of penetration than single applicators. Their most significant drawback has been the inability to determine the appropriate phasing necessary to focus onto a tumor location. This paper presents simulated results of a novel method, designed to overcome this problem. By precisely determining the appropriate phase coefficients and utilizing the conjugated, incoherent tumor emissions, the array can be noninvasively controlled and retro-focused onto the tumor.