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Saturated double-angle method for rapid B1+ mapping.

Charles H Cunningham·John M Pauly·Krishna S Nayak
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Abstract

For in vivo magnetic resonance imaging at high field (> or =3 T) it is essential to consider the homogeneity of the active B(1) field (B(1)+), particularly if surface coils are used for RF transmission. A new method is presented for highly rapid B(1)+ magnitude mapping. It combines the double angle method with a B(1)-insensitive magnetization-reset sequence such that the choice of repetition time (TR) is independent of T(1) and with a multislice segmented (spiral) acquisition to achieve volumetric coverage with adequate spatial resolution in a few seconds. Phantom experiments confirmed the accuracy of this technique even when TR << T(1), with the side effect being lowered SNR. The speed of this method enabled B(1)+ mapping in the chest and abdomen within a single breath-hold. In human cardiac imaging, the method enabled whole-heart coverage within a single 16-s breath-hold. Results from phantoms and healthy volunteers at 1.5 T and 3 T are presented.

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AlgorithmsHeartHumansImage EnhancementImage Interpretation, Computer-AssistedInformation Storage and RetrievalMagnetic Resonance ImagingSignal Processing, Computer-AssistedEvaluation StudyJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov't

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BibTeXRIS

Charles H Cunningham, John M Pauly, Krishna S Nayak. 2006. Saturated double-angle method for rapid B1+ mapping.. https://doi.org/10.1002/mrm.20896

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