Leeor Alon1, 2, Cem Murat Deniz1, 2, Ryan Brown1, Daniel Sodickson1, 2, Yudong Zhu1, 2
1Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University, New York, NY, United States; 2Sackler Institute of Graduate Biomedical Sciences, New York University, New York, NY, United States
In Magnetic Resonance Imaging, local and global specific absorption rates (SAR) are metrics needed to ensure patient safety. Even though global SAR can be effectively monitored in-vivo for single and multi-channel transmit systems, local SAR is much harder to assess. Often, Local SAR estimation utilizes numerical simulation software to model particular coil setups and calculate the electromagnetic fields associated with the simulated coil setups. In this work, it is shown that even relatively slight inaccuracies in the modeled coil geometry could significantly alter the E field and SAR distribution while leaving the maximum B1+ field change relatively unperturbed. This alteration of the E field and SAR distribution are also seen to increase with field strength, suggesting possible shortcomings of using simulation software and comparing the B1+ maps of simulations and experiments to account for RF safety of coil arrays.
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