Jonathan R. Polimeni1, Kawin Setsompop1, Borjan A. Gagoski2, Jennifer A. McNab1, Christina Triantafyllou1, 3, Lawrence L. Wald1, 4
1Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, United States; 2Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States; 3A. A. Martinos Imaging Center, McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, United States; 4Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, United States Minor Outlying Islands
Highly-accelerated imaging allows for rapid single-shot EPI acquisitions to mitigate distortion and blurring effects. However there is an intrinsic SNR penalty that scales with the square-root of the acceleration factor and with the g-factor, ultimately limiting its usability. Multi-shot segmented EPI acquisitions can similarly mitigate these deleterious effects, yet the longer temporal sampling interval amplifies physiological noise and system instabilities. Here, we merge a segmented multi-shot EPI acquisition with the Simultaneous Multi-Shot technique. This combination of techniques allows each EPI segment to employ a distinct multi-slice excitation pulse, enabling advantageous slice-aliasing patterns to reduce the g-factor of the image reconstruction.
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