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Abstract #0116

Reduction of Diffusion-Weighted Readout-Segmented EPI Scan Time Using a Blipped-CAIPI Modification

Robert Frost1, David A. Porter2, Gwenaelle Douaud1, Peter Jezzard1, Karla L. Miller1

1FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; 2Healthcare Sector, Siemens AG, Erlangen, Germany

Readout-segmented EPI (rs-EPI) for diffusion imaging reduces distortion and T2* blurring and enables higher resolution relative to single-shot EPI (ss-EPI). However, the long scan times caused by segmenting the acquisition of k-space limit the number of slices and/or diffusion directions. A blipped-CAIPI multiband modification to rs-EPI has the potential to address the scan time issue and is demonstrated here with slice acceleration factor two. Trace-weighted images with 0.9x0.9x4mm resolution acquired in clinically relevant scan times are presented. Diffusion tractography is compared from data acquired at 2 and 1.5mm isotropic resolution for rs- and ss-EPI.

Keywords

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