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PubMed · 10828192

High-resolution diffusion imaging using a radial turbo-spin-echo sequence: implementation, eddy current compensation, and self-navigation.

M H Seifert·P M Jakob·V Jellus·A Haase·C Hillenbrand
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Abstract

This work describes a segmented radial turbo-spin-echo technique (DW-rTSE) for high-resolution multislice diffusion-weighted imaging and quantitative ADC mapping. Diffusion-weighted images with an in-plane resolution of 700 microm and almost free of bulk motion can be obtained in vivo without cardiac gating. However, eddy currents and pulsatile brain motion cause severe artifacts when strong diffusion weighting is applied. This work explains in detail the artifacts in projection reconstruction (PR) imaging arising from eddy currents and describes an effective eddy current compensation based on the adjustment of gradient timing. Application of the diffusion gradients in all three orthogonal directions is possible without degradation of the images due to eddy current artifacts, allowing studies of the diffusional anisotropy. Finally, a self-navigation approach is proposed to reduce residual nonrigid body motion artifacts. Five healthy volunteers were examined to show the feasibility of this method.

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AnisotropyArtifactsBrainEcho-Planar ImagingFeasibility StudiesHumansImage Processing, Computer-AssistedPhantoms, ImagingReference ValuesComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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M H Seifert, P M Jakob, V Jellus, A Haase, C Hillenbrand. 2000. High-resolution diffusion imaging using a radial turbo-spin-echo sequence: implementation, eddy current compensation, and self-navigation.. https://doi.org/10.1006/jmre.2000.2041

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