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Abstract #2741

Performance Comparison of Parallel Transmit Arrays for Body Imaging at 3 T Under Local SAR Constraint

Bastien Gurin1, Matthias Gebhardt2, Peter Serano1, Elfar Adalsteinsson3, Michael Hamm2, Josef Pfeuffer2, Juergen Nistler2, Lawrence L. Wald1

1Radiology, Massachusetts General Hospital, Charlestown, MA, United States; 2Siemens Healthcare, Erlangen, Germany; 3Electrical Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States

Little theoretical work has been done optimizing pTx array geometries and number of Tx channels. We simulate eight 3T body pTx arrays with varying number and distribution of Tx channels. We design transverse and coronal RF shimming and 2-spoke pulses subject to local SAR constraint. We show that adding Tx channels improves the local SAR vs. fidelity tradeoff however at the cost of increased power. For arrays with at least 8 Tx channels per row, it is beneficial to add channels in the z-direction as opposed to only in the transverse direction, especially for imaging in the coronal orientation.

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Keywords

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