Heat penetration in microwave hyperthermia based on infrared thermography

According to the electromagnetic theory, permeating depth of the 2 450 MHz microwave in homogeneous media is analyzed. A nonlinear heat transfer model is applied to predict the temperature variation in biotissues under the microwave irradiation. Based on the thermal images measured by an far-infrared imager, the heat penetration of multi-layered homogeneous medium simulating biomaterial is studied. The experimental results show the difference between permeating depth and heat penetration. The heat penetration is mainly related to the power of microwave antenna, distance between antenna and biomaterial, and duration of irradiation, etc. Adopting high power microwave, long irradiation duration or close distance can enhance heat penetration in the human body.