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Abstract #1729

Combination of SPECIAL and 2D SSE Parallel Transmit Pulses for Volume Selection in MR Spectroscopy

Patrick Waxmann1, Tomasz Dawid Lindel1, Florian Schubert1, Bernd Ittermann1, Ralf Mekle1

1Physikalisch-Technische Bundesanstalt, Braunschweig & Berlin, Germany

Starting with a SPECIAL sequence for localized spectroscopy, we kept the initial plane inversion pulse and replaced the conventional excitation pulse with a 4-fold accelerated 2D spatially selective excitation (SSE) pulse. A refocusing pulse is no longer needed for voxel definition and was eliminated, thus reducing the minimum echo time to 1.5 ms. This sequence allows to excite voxels of uniform thickness but arbitrary shape in two dimensions. It was implemented on a 3 T scanner equipped with 8 Tx channels. In phantoms, good spatial selectivity was demonstrated in imaging and spectroscopy experiments.

Keywords

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