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Abstract #4259

Improved Off-Resonance Correction for segmented Spatially Selective Excitation Pulses to Achieve Large Excitation Bandwidth

Patrick Waxmann1, Tomasz Dawid Lindel1, Frank Seifert1, Bernd Ittermann1, Ralf Mekle1

1Physikalisch-Technische Bundesanstalt, Berlin, Germany, Germany

Single voxel MR spectroscopy desires to acquire spectra from an anatomically defined region of interest. Spatially selective excitation (SSE) has been studied to adapt the voxel shape to the anatomy. Segmentation of SSE pulses can enhance the excitation bandwidth. Here, we introduce an off-resonance correction for segmented SSE-pulses designed with a small-tip-angle algorithm. The pulses can be designed as a whole and segmented only afterwards. This correction enhances target pattern fidelity even for large off-resonances and thus provides for uniform voxel localization over a wide frequency range.

Keywords

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