Abstract #2211

SAR/B1+ calibration workflow for safe, high duty-cycle parallel transmission imaging at ultra-high field

Filiz Yetisir¹, Bastien Guerin², Lawrence Wald^2,3, and Elfar Adalsteinsson^1,3

¹Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States, ²Dept.of Radiology, Martinos Center for Biomedical Imaging, Charlestown, MA, United States, ³Harvard-MIT Division of Health Sciences Technology, Institute of Medical Engineering and Science, Cambridge, MA, United States

In this work, we propose a pTX safety workflow that will enable high duty cycle imaging at high field systems. Several SAR and B₁⁺ calibration steps are suggested for a complete analysis including modeling the TX array, testing it over time and different loads and finding a safety margin to account for RF system imperfections. Good qualitative agreement was achieved between the simulated and measured B₁⁺ maps for the TX array. 11% and 6° standard deviation was observed in the magnitude and the relative phase maps over time. A maximum difference of 16% was observed between offline and online calculated local SAR values due to RF system imperfections.

This abstract and the presentation materials are available to members only; a login is required.

Join Here