Patient-Specific SAR Models and in Vivo Validation

Hanno Homann¹, Ingmar Graesslin², Holger Eggers², Kay Nehrke², Peter Brnert², Olaf Dssel¹

Dielectric body models are increasingly used for safety assessment of the local specific absorption rate (SAR). In this work, a new method for the generation of dielectric body models from MR images was developed. The method is based on a water-fat-separation of MR images and an expectation-maximization (EM) segmentation of the 2D histogram. Models of five subjects in different body poses were generated and simulated using the finite-differences time-domain (FDTD) method. Validation of the simulated fields against measured B1 field maps was performed.