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PubMed · 10748434

Rapid autocorrection using prescan navigator echoes.

K P McGee·J P Felmlee·A Manduca·S J Riederer·R L Ehman
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Abstract

Autocorrection is an adaptive motion correction algorithm that does not require an in vivo measurement of the motion record. A novel method for ensuring convergence of this algorithm when motion is severe is presented. A limited number of navigator echoes are acquired before the imaging sequence to obtain a "snapshot" of the object. Phase differences between the navigator and image k-space data are used as an estimate of motion-induced phase shifts in the image, followed by autocorrection. In phantom data a six-fold reduction in computation time compared to autocorrection alone was realized. These results indicate that this navigator/autocorrection combination may be useful for reducing motion artifacts and computation time for MR exams when motion along the image phase encoding axis is severe.

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AlgorithmsArtifactsAutomationHumansImage EnhancementMagnetic Resonance ImagingModels, TheoreticalMotionPhantoms, ImagingSensitivity and SpecificityWristComparative StudyJournal Article

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BibTeXRIS

K P McGee, J P Felmlee, A Manduca, S J Riederer, R L Ehman. 2000. Rapid autocorrection using prescan navigator echoes.. https://doi.org/10.1002/(sici)1522-2594(200004)43%3A4%3C583%3A%3Aaid-mrm13%3E3.0.co%3B2-b

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