Phase-Sensitive Inversion Recovery for Myocardial T1 Mapping with Motion Correction and Parametric Fitting

The assessment of myocardial fibrosis and extracellular volume requires accurate estimation of myocardial T(1)s. While image acquisition using the modified Look-Locker inversion recovery technique is clinically feasible for myocardial T-1 mapping, respiratory motion can limit its applicability. Moreover, the conventional T-1 fitting approach using the magnitude inversion recovery images can lead to less stable T-1 estimates and increased computational cost. In this article, we propose a novel T-1 mapping scheme that is based on phase-sensitive image reconstruction and the restoration of polarity of the MR signal after inversion. The motion correction is achieved by registering the reconstructed images after background phase removal. The restored signal polarity of the inversion recovery signal helps the T-1 fitting resulting in improved quality of the T-1 map and reducing the computational cost. Quantitative validation on a data cohort of 45 patients proves the robustness of the proposed method against varying image contrast. Compared to the magnitude T-1 fitting, the proposed phase-sensitive method leads to less fluctuation in T-1 estimates. (C) 2012 Wiley Periodicals, Inc.