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Abstract #2733

In Vivo B1-Based SAR Determination in a Multi-Transmit System with DREAM

Ulrich Katscher1, Kay Nehrke1, Hanno Homann1, Peter Brnert1

1Philips Research Europe-Hamburg, Hamburg, Germany

A central issue of parallel RF transmission is the SAR management to ensure patient safety. As an alternative to the usually applied model-based SAR estimation, a new method has been proposed to estimate SAR from the acquired B1 maps. This B1-based SAR determination was successfully tested for quadrature (single channel) excitation in vivo and non-quadrature (multi-channel) excitation in a phantom study. This study adapts B1-based SAR determination for non-quadrature excitation in vivo. To this goal, local SAR in thighs and pelvis of a volunteer is investigated and compared with results of corresponding FDTD simulations based on the same volunteer. <

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Keywords

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