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PubMed · 10748424

Phase-contrast with interleaved undersampled projections.

A V Barger·D C Peters·W F Block·K K Vigen·F R Korosec·T M Grist·C A Mistretta
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Abstract

MR phase-contrast techniques provide velocity-sensitive angiograms and quantitative flow measurements but require long scan times. Recently it has been shown that undersampled projection reconstruction can acquire higher resolution per unit time than Fourier techniques with acceptable artifacts when used in contrast-enhanced MR angiography. Undersampled projection reconstruction has similar potential for phase-contrast acquisitions. Flow sensitization gradients are used with projection trajectories to acquire velocity-dependent phase information. An acquisition scheme that acquires three flow encoding directions on three sets of angular-interleaved projections is introduced. Depending on the resolution, acquisition times for 3D datasets can decrease by factors of two to four.

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ArtifactsBlood Flow VelocityCircle of WillisHumansImage EnhancementMagnetic Resonance AngiographyModels, TheoreticalPhantoms, ImagingPulsatile FlowReference ValuesSensitivity and SpecificitySpectroscopy, Fourier Transform InfraredClinical TrialComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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A V Barger, D C Peters, W F Block, K K Vigen, F R Korosec, T M Grist, C A Mistretta. 2000. Phase-contrast with interleaved undersampled projections.. https://doi.org/10.1002/(sici)1522-2594(200004)43%3A4%3C503%3A%3Aaid-mrm3%3E3.0.co%3B2-0

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