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PubMed · 9621921

GRASE imaging at 3 Tesla with template interactive phase-encoding.

J Jovicich·D G Norris
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Abstract

A new method for ordering the phase-encoding gradient is proposed, and an application for short effective TE gradient- and spin-echo (GRASE) imaging is demonstrated. The proposed method calculates the phase-encoding order from the signal decay of a template scan (hence "template interactive phase-encoding" or TIPE). Computer simulations are used to compare the point spread functions of different phase-encoding orders giving short effective echo times (kb centric GRASE, centric GRASE, centric TIPE). The conventional centric phase-encoding order is also considered for GRASE. The conventional centric method is sensitive to both amplitude and phase modulation of the signal in k-space. The centric TIPE method gives the least amplitude modulation artifacts but is vulnerable to phase artifacts. The TIPE experiment was implemented on a 3 Tesla system. To the best of our knowledge, we present the first in vivo GRASE images at this field strength.

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ArtifactsBiophysical PhenomenaBiophysicsBrainComputer SystemsEcho-Planar ImagingHumansImage EnhancementImage Processing, Computer-AssistedMagnetic Resonance ImagingPhantoms, ImagingReference ValuesSensitivity and SpecificityJournal Article

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J Jovicich, D G Norris. 1998. GRASE imaging at 3 Tesla with template interactive phase-encoding.. https://doi.org/10.1002/mrm.1910390615

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