Development and Laboratory Testing of a Noninvasive Intracranial Focused Hyperthermia System

During the past two decades, a great deal of research has been carried out with the aim of developing effective techniques for hyperthermia treatment, primarily using RF, microwave, and ultrasound energy. A system for deep brain hyperthermia treatment, designed to also provide passive measurements of temperature and/or conductivity variations inside the human body, is presented in this paper. The proposed system comprises both therapeutic and diagnostic modules, operating in a totally contactless way, based on the use of an ellipsoidal beamformer to achieve focusing on the areas under treatment and monitoring. In previous publications, the performance of the system´s diagnostic module in phantom, animal, and human studies has been reported. In the current research, new theoretical and experimental results using the therapeutic hyperthermia module of the system are presented. The main scope of the theoretical analysis is the improvement of the system´s focusing attributes. Moreover, phantom experimental results verify the proof of concept. Both computation and phantom measurement results show that deep focused brain hyperthermia may be achievable with adequate spatial resolution and sensitivity using the proposed methodology, subject to the appropriate combination of operation frequency and low-loss dielectric material used as filling in the ellipsoidal.