SAR analysis of a re-entrant resonant cavity applicator for brain tumor hyperthermia treatment with a 3-D anatomical human head model

A re-entrant resonant cavity applicator system for non-invasive brain tumor hyperthermia treatments was presented. We have already confirmed the effectiveness of the heating properties of this heating system with cylindrical agar phantoms and with computer simulations. This paper describes the specific absorption rate (SAR) analysis of this heating system for non-invasive brain tumor hyperthermia treatments. The purpose of this study is to present the capability of this heating system with the developed three-dimensional (3-D) anatomical human head model using the finite element method (FEM). First, a method of reconstructing a 3-D anatomical human head model from two-dimensional (2-D) MRI and X-ray CT images using 3D-CAD software was described. Second, the results of the SAR distributions of this heating system with the developed 3-D anatomical human model were presented. According to our computer simulations, a hot spot was not generated in either eyeball. From these results, we found that the possibility of clinical heating using the developed heating system was confirmed by estimating SAR distributions with a 3-D anatomical human head model.