Induced Current Electro-Thermal Imaging in A Realistic Breast Model: A Numerical Study

Passive (standard) thermography is a medical imaging modality that visualizes the surface temperature distribution by detecting infrared (IR) radiation emitted from the body surface through an IR camera. Passive IR imaging has begun to be used in routine health screenings; however, the effectiveness of passive thermography in detecting small and deep tumors is limited. Active thermography uses an external heat source to detect deeper tumors. In this study, the induced currents generated by time-varying magnetic fields at a frequency of 750 kHz, depending on the dielectric parameter distribution of the breast tissue, were used as an external heat source. The current-induced medical electro-thermal imaging method was numerically investigated using a realistic breast model. In the simulation study, tumor and breast tissues were modeled in three dimensions, and the bio-heat equation for the active mode was solved using realistic values of the tissue layers. A 4 A current was applied to a 25 winding Helmholtz coil, and the electric field, current density, induced power, and temperature distributions were analyzed. The results showed that a 1 cm
³
malignant tumor could be detected at a depth of 19 mm in a realistic breast model.