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Abstract #3477

Nonlinear RF Pulse Optimization for Segmented Multi-Dimensionally Selective Excitation with Parallel Transmit

Martin Haas1, Jeff Snyder1, Jrgen Hennig1, Maxim Zaitsev1

1Department of Radiology, Medical Physics, University Medical Center Freiburg, Freiburg, Germany

The duration of multi-dimensionally spatial selective excitation (SSE) RF pulses usually implies high excitation fidelity of a given target pattern only for a narrow range of frequencies. Segmentation of an SSE pulse across several repetitions results in short RF pulses and broadband excitation of the target pattern in the summed signal. In this work, a generalized nonlinear large tip angle RF optimization algorithm is presented which jointly optimizes the RF segments and thus extends previous approaches using small tip angles or segment-wise large tip angle optimization.

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Keywords

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