In Vivo B1-Based SAR Determination in a Multi-Transmit System with DREAM

Ulrich Katscher¹, Kay Nehrke¹, Hanno Homann¹, Peter Brnert¹

A central issue of parallel RF transmission is the SAR management to ensure patient safety. As an alternative to the usually applied model-based SAR estimation, a new method has been proposed to estimate SAR from the acquired B1 maps. This B1-based SAR determination was successfully tested for quadrature (single channel) excitation in vivo and non-quadrature (multi-channel) excitation in a phantom study. This study adapts B1-based SAR determination for non-quadrature excitation in vivo. To this goal, local SAR in thighs and pelvis of a volunteer is investigated and compared with results of corresponding FDTD simulations based on the same volunteer. <