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Abstract #2612

Simulation Study of Parallel Transmit Arrays for 3T Body Imaging Under Local and Global SAR Constraints

Bastien Guerin1, Matthias Gebhardt2, Peter Serano1, Elfar Adalsteinsson3, 4, Michael Hamm2, Josef Pfeuffer2, Juergen Nistler2, Lawrence L. Wald1, 4

1Martinos Center for Biomedical Imaging, Dept. of Radiology, Massachusetts General Hospital, Charlestown, MA, United States; 2Siemens Healthcare, Erlangen, Germany; 3Dept of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States; 4Harvard-MIT Division of Health Sciences Technology, Cambridge, MA, United States

Despite intense research in pTx hardware development there has been little theoretical work on the benefit of increasing the number of transmit channels. In this work we compare the performance of three pTx arrays with 4, 8 and 16 channels using an HFSS/ADS co-simulation and a pulse design algorithm constraining simultaneously global/local SAR and average/maximum forward power. We show that increasing the number of channels from 4 to 16 allows reduction of local SAR by as much as 90% for constant excitation error and reduction of excitation error by as much as 10% for constant local SAR (2 spokes excitations).

Keywords

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