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Abstract #4572

Influence of Off-Resonance in Myocardial T1-Mapping Using SSFP Based MOLLI Method

Peter Kellman1, Daniel A. Herzka2, Andrew E. Arai1, Michael Schacht Hansen3

1NHLBI, NIH, Bethesda, MD, United States; 2Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States; 3NHLBI, National Institutes of Health, Bethesda, MD, United States

The frequency dependence of SSFP imaging is well known and results in dark band artifacts. Myocardial T1-mapping methods such as MOLLI use single shot SSFP readout and are prone to error in T1-measurement that is frequency dependent. A low excitation flip angle is used in MOLLI to reduce errors that result from influence of readout and improve T1-measurement accuracy. It may be less well appreciated that an additional significant frequency-dependent error in T1 results at relatively small off-resonance frequency deviations that are typically observed in the SSFP passband.

Keywords

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