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Dynamic T1 measurement using snapshot-FLASH MRI.

A Jivan·M A Horsfield·A R Moody·G R Cherryman
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Abstract

The application of an inversion-recovery snapshot FLASH (fast low-angled shot) imaging sequence to the dynamic measurement of monoexponential T1 relaxation was investigated. The effect of (a) a reduction in the overall sequence repetition time, and (b) an increase of the read-pulse flip angle, on the measurement of T1 was analyzed. The error in T1 introduced by these factors is calculated, and a fuller analysis that takes them into account is presented. Data from a phantom are used to confirm this analysis. The magnitude of the errors is illustrated by measuring myocardial T1 in patients with acute ischaemic heart disease during the injection of a bolus of the contrast medium gadobenate dimeglumine. Overall, there was a 10% difference between the T1 values when the approximate and exact solutions were used; this was statistically significant. However, the difference was on average 25% for patients with a high heart rate (because of the shorter sequence-repetition time) in areas of infarcted myocardium (because of the longer T1).

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Contrast MediaGadoliniumHumansMagnetic Resonance ImagingMeglumineMyocardial InfarctionMyocardiumOrganometallic CompoundsPhantoms, ImagingJournal Article

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BibTeXRIS

A Jivan, M A Horsfield, A R Moody, G R Cherryman. 1997. Dynamic T1 measurement using snapshot-FLASH MRI.. https://doi.org/10.1006/jmre.1997.1177

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