Robert Frost1, Karla L. Miller1, David A. Porter2, Rob H. N. Tijssen3, Peter Jezzard1
1FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; 2Healthcare Sector, Siemens AG, Erlangen, Germany; 3Department of Radiotherapy, UMC Utrecht, Utrecht, Netherlands
We present a 3D multi-slab readout-segmented echo-planar imaging (rs-EPI) sequence for diffusion imaging that minimizes motion-induced phase artefacts with 2D navigator correction and real-time reordering of k-space with respect to the cardiac cycle. Options for acquisition schemes and motion-induced phase corrections were simulated and the chosen strategy was implemented by modifying a standard 2D rs-EPI sequence. Real-time cardiac reordering is validated in simulations and experiment, demonstrating 40-50% reduced variability in a time series of diffusion images compared to a sequential k-space acquisition. The 3D multi-slab rs-EPI method is demonstrated in-vivo and is shown to provide excellent image fidelity.