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Abstract #4271

Fast B1+ Mapping for Cardiac MR Using a Black Blood DREAM Sequence

Kay Nehrke1, Alois M. Sprinkart2, 3, Hans H. Schild2, Peter Brnert1

1Philips Research Laboratory, Hamburg, Germany; 2Department of Radiology, University of Bonn, Bonn, Germany; 3Institute of Medical Engineering, Ruhr-University Bochum , Bochum, Germany

The recently introduced DREAM B1+ mapping approach has been combined with a black-blood prepulse to allow a 2D B1+ map of the heart to be acquired in the diastolic phase of a single heart beat. The approach has been studied in vivo for RF shimming of the heart using a dual-transmit 3T MRI system. Application of the black blood prepulse facilitated automatic threshold-based masking of the B1+ maps, thus improving the reliability of the maps. RF shimming resulted in significant improvement of RF homogeneity.

Keywords

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