Influence of Non-Conductive Probes on Specific Absorption Rate

Sukhoon Oh¹, Christopher M. Collins¹

Recently, there are an increasing number of interventional studies in which minimally invasive procedures are performed using MRI guidance using thin and precisely controlled devices and sensors. The influence of non-conductive devices on the specific absorption rate (SAR) in surrounding tissues are rarely investigated compared to studies investigating safety issues of metallic probes and devices. Here, we show that even non-conductive probes, in our case fiber optic thermal sensors, can have notable effects on SAR. Numerical calculations, based on the finite-difference time-domain (FDTD) method at 3 T, clearly show increased SAR around the non-conductive probes in a conductive phantom.