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PubMed · 11590645

Embedded MR fluoroscopy: high temporal resolution real-time imaging during high spatial resolution 3D MRA acquisition.

S B Fain·S J Riederer·J Huston·B F King
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Abstract

A method termed "embedded fluoroscopy" for simultaneously acquiring a real-time sequence of 2D images during acquisition of a 3D image is presented. The 2D images are formed by periodically sampling the central phase encodes of the slab-select direction during the 3D acquisition. The tradeoffs in spatial and temporal resolution are quantified by two parameters: the "redundancy" (R), the fraction of the 3D acquisition sampled more than once; and the "effective temporal resolution" (T), the time between temporal updates of the central views. The method is applied to contrast-enhanced MR angiography (CE-MRA). The contrast bolus dynamics are portrayed in real time in the 2D image sequence while a high-resolution 3D image is being acquired. The capability of the 2D acquisition to measure contrast enhancement with only a 5% degradation of the spatial resolution of the 3D CE-MR angiogram is shown theoretically. The method is tested clinically in 15 CE-MRA patient studies of the carotid and renal arteries.

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Feasibility StudiesFluoroscopyHumansImaging, Three-DimensionalMagnetic Resonance AngiographyMathematicsPhantoms, ImagingTime FactorsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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S B Fain, S J Riederer, J Huston, B F King. 2001. Embedded MR fluoroscopy: high temporal resolution real-time imaging during high spatial resolution 3D MRA acquisition.. https://doi.org/10.1002/mrm.1247

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