Conductive Titanium Dioxide for Hyperthermia Study on Liver Equivalent Phantom

Abstract

　Hyperthermia is one of the methods used in combination with medication in cancer treatment. The development of a device with minimal impact on the human body and high therapeutic effect is required for this method, and it is considered necessary to demonstrate the heating effect using a living body. On the other hand, experiments using the human body or animals raise ethical issues, and an electromagnetic phantom that mimics the electrical characteristics of the human body (relative permittivity and conductivity) is useful. In this study, we aimed to develop a liver-equivalent phantom at 8 MHz, which is the frequency of electromagnetic waves often used in hyperthermia and measured the electrical characteristics of mouse liver to determine target values. Furthermore, the electrical characteristics were adjusted by changing the composition ratio of the phantom materials, and a prototype liver phantom was fabricated. The electrical properties of the phantom sufficiently mimicked those of the mouse liver at 8 MHz, with errors of 5.0 % in relative permittivity and 17 % in conductivity.