Control of Heating Pattern for Interstitial Microwave Hyperthermia by a Coaxial-Dipole Antenna-Aiming at Treatment of Brain Tumor

摘要

Interstitial microwave hyperthermia is one of the modalities for cancer treatment that insert a thin microwave antenna into the affected part to selectively heat only the tumor. The authors are investigating this technique with an aim of clinical applications of this medical treatment for brain tumors. In the clinical treatment of brain tumors, it is more critical that "only the tumor parts be heated" than for the treatment of other tissues. Therefore, an antenna that can generate a localized heating pattern on the tumor is required. Although the heating pattern can be controlled here in the longitudinal direction of the antenna by using multiple antennas to form an array applicator, control of the heating pattern in the axial direction is relatively difficult. In this paper, to enable the heating pattern to be controlled in the axial direction, the authors introduced a coaxial-dipole rnantenna and improved its structure. In addition, they assumed that it was actually applied in the medical treatment of brain tumors and used a numerical calculation model that included a tumor created from MR images to verify the effectiveness of the improved coaxial-dipole antenna according to numerical calculations.