Magnetic Resonance Thermometry During the Localized Heating of Biological Tissues

Abstract

In this paper, a state estimation problem is solved with the Steady-State Kalman filter for the nonintrusive measurements of the temperature inside the human body, with the magnetic resonance technique. The paper is focused on temperature measurements during the hyperthermia treatment of cancer imposed by radiofrequency waves. The coupled bioheat transfer and electromagnetic problems are numerically solved in a realistic twodimensional geometry obtained from the Visual Human Dataset. The tumor is considered loaded with nanoparticles in order to improve the localized absorption of the radiofrequency waves and to avoid the undesired heating of healthy tissues. Numerical results demonstrate that the present Steady-State Kalman filter solution is more accurate than the direct data inversion, which is commonly used for recovering the local transient temperature variation from the magnetic resonance measurements.