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Abstract #0288

Local SAR Estimation for Human Brain Imaging Using Multi-Channel Transceiver Coil at 7T

Xiaotong Zhang1, Sebastian Schmitter2, Jiaen Liu1, Pierre-Francois Van de Moortele2, Bin He1, 3

1Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, United States; 2Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States; 3Institute for Engineering in Medicine, University of Minnesota, Minneapolis, MN, United States

Parallel transmission technique has been recognized as a potential powerful tool for B1 inhomogeneities compensation at UHF; however, elevated SAR associated with increased main magnetic field strength remains as a major safety concern in its application. A B1-based subject-specific local SAR estimation approach for single channel transmission is presented in this study, and has been demonstrated in a human brain imaging experiment at 7T using a 16-channel transceiver head coil. The present approach holds strong promises for enabling subject-specific local SAR prediction, which in turn can be used for explicit constraint in B1 shimming and multi-transmit RF pulse design.

Keywords

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