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Abstract #1377

An Intuitive Model of Several Factors Affecting Accuracy of MOLLI T1 Values

Kelvin Chow1, Joseph J. Pagano1, Richard B. Thompson1

1Biomedical Engineering, University of Alberta, Edmonton, Alberta, Canada

The MOLLI sequence commonly used for myocardial T1 quantification is known to have systematic errors dependent on T1 and T2 values, although the interaction of these effects is not well understood. We propose an intuitive model for predicting MOLLI errors based on the magnetization perturbation of the imaging readout (Mdiff), incorporating the effects of tissue relaxation and other sequence parameters. Experiments in phantoms show highly variable MOLLI accuracy that is strongly correlated with Mdiff, due to varying magnetization perturbation caused by different T2/T1 values. Common sequence parameter changes also alter MOLLI accuracy in a way predicted by the Mdiff model.

Keywords

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