Christina Triantafyllou1, 2, Jonathan R. Polimeni3, Jennifer A. McNab3, Thomas Witzel3, Lawrence L. Wald3, 4
1A.A. Martinos Imaging Center, McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA, United States; 2A.A. Martinos Center for Biomedical Imaging, Department of Radiology, , MGH, Charlestown, MA, United States; 3A.A. Martinos Center for Biomedical Imaging, Department of Radiology,, MGH, Charlestown, MA, United States; 4Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, United States
In this study, we compare two different acquisitions; Accelerated (GRAPPA) single-shot and non-accelerated mutli-shot EPI with matched effective echo spacing. Our findings demonstrate that in both thermal and physiological noise dominated acquisitions, when the temporal sampling interval is matched, by temporally smoothing the single-shot time-series, the single-shot accelerated time-series result in higher tSNR. But if the fixed duration scan can afford reduced temporal resolution (sampling interval not matched), then the slower multi-shot strategy provides slightly higher tSNR than the distortion matched single-shot acquisition.
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