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Evaluation of slice accelerations using multiband echo planar imaging at 3 T.

ABSTRACT: We evaluate residual aliasing among simultaneously excited and acquired slices in slice accelerated multiband (MB) echo planar imaging (EPI). No in-plane accelerations were used in order to maximize and evaluate achievable slice acceleration factors at 3 T. We propose a novel leakage (L-) factor to quantify the effects of signal leakage between simultaneously acquired slices. With a standard 32-channel receiver coil at 3 T, we demonstrate that slice acceleration factors of up to eight (MB=8) with blipped controlled aliasing in parallel imaging (CAIPI), in the absence of in-plane accelerations, can be used routinely with acceptable image quality and integrity for whole brain imaging. Spectral analyses of single-shot fMRI time series demonstrate that temporal fluctuations due to both neuronal and physiological sources were distinguishable and comparable up to slice-acceleration factors of nine (MB=9). The increased temporal efficiency could be employed to achieve, within a given acquisition period, higher spatial resolution, increased fMRI statistical power, multiple TEs, faster sampling of temporal events in a resting state fMRI time series, increased sampling of q-space in diffusion imaging, or more quiet time during a scan.

SUBMITTER: Xu J

PROVIDER: S-EPMC3815955 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Evaluation of slice accelerations using multiband echo planar imaging at 3 T.

Xu Junqian J Moeller Steen S Auerbach Edward J EJ Strupp John J Smith Stephen M SM Feinberg David A DA Yacoub Essa E Uğurbil Kâmil K

NeuroImage 20130727

We evaluate residual aliasing among simultaneously excited and acquired slices in slice accelerated multiband (MB) echo planar imaging (EPI). No in-plane accelerations were used in order to maximize and evaluate achievable slice acceleration factors at 3 T. We propose a novel leakage (L-) factor to quantify the effects of signal leakage between simultaneously acquired slices. With a standard 32-channel receiver coil at 3 T, we demonstrate that slice acceleration factors of up to eight (MB=8) wit ...[more]

PMID: 23899722

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Evaluation of slice accelerations using multiband echo planar imaging at 3 T.

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Evaluation of slice accelerations using multiband echo planar imaging at 3 T.

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