Thermal images of electrically stimulated breast: A simulation study

Abstract

The thermal and electrical properties of biological tissues are different. It is also known that the electrical conductivity and metabolic heat source of tissues change de-pending on their state of health. Different thermal end electrical properties of tissues cause thermal emissions, and thermal imaging goes on very important and vital point. Infrared imaging has a limited performance for the breast cancer diagnosis due to patient moving and detector sensitivities. However, this performance can be improved by applying currents at different frequencies in medical safety limits. Due to the different electrical properties of tissues, temperature differences of tissues can be increased by the help of current application and malignant tissue can be distinguished from the healthy tissue in the thermal image. In this study, a two-dimensional model of breast and cancerous tissue is developed. To obtain the temperature distribution, Pennes Bio Heat Equation is solved with the finite element method. Secondary heat sources are generated in the model by applying currents from the boundary and solving the resulting electric field. Simulations are implemented for different tumor locations and at different frequencies for the same object. Different temperature distributions are obtained by changing the frequency of the stimulation current and corresponding frequency value. It is shown that imaging performance can be increased with the applied currents, and tumors can be sensed 5 cm away from the surface with the state-of-the-art thermal infrared imagers. © 2010 International Federation for Medical and Biological Engineering.