Dataset Information

Scan time reduction for readout-segmented EPI using simultaneous multislice acceleration: Diffusion-weighted imaging at 3 and 7 Tesla.

ABSTRACT:

Purpose

Readout-segmented echo-planar imaging (rs-EPI) can provide high quality diffusion data because it is less prone to distortion and blurring artifacts than single-shot echo-planar imaging (ss-EPI), particularly at higher resolution and higher field. Readout segmentation allows shorter echo-spacing and echo train duration, resulting in reduced image distortion and blurring, respectively, in the phase-encoding direction. However, these benefits come at the expense of longer scan times because the segments are acquired in multiple repetitions times (TRs). This study shortened rs-EPI scan times by reducing the TR duration with simultaneous multislice acceleration.

Methods

The blipped-CAIPI method for slice acceleration with reduced g-factor SNR loss was incorporated into the diffusion-weighted rs-EPI sequence. The rs- and ss-EPI sequences were compared at a range of resolutions at both 3 and 7 Tesla in terms of image fidelity and diffusion postprocessing results.

Results

Slice-accelerated clinically useful trace-weighted images and tractography results are presented. Tractography analysis showed that the reduced artifacts in rs-EPI allowed better discrimination of tracts than ss-EPI.

Conclusion

Slice acceleration reduces rs-EPI scan times providing a practical alternative to diffusion-weighted ss-EPI with reduced distortion and high resolution. Magn Reson Med 74:136-149, 2015. © 2014 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.

SUBMITTER: Frost R

PROVIDER: S-EPMC4854329 | biostudies-literature |

REPOSITORIES: biostudies-literature

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