1 research outputs found
Myocardial T1, T2, T2*, and fat fraction quantification via low-rank motion-corrected cardiac MR fingerprinting
PURPOSE: Develop a novel 2D cardiac MR fingerprinting (MRF) approach to enable simultaneous T1, T2, T2*, and fat fraction (FF) myocardial tissue characterization in a single breathâhold scan. METHODS: Simultaneous, coâregistered, multiâparametric mapping of T1, T2, and FF has been recently achieved with cardiac MRF. Here, we further incorporate T2* quantification within this approach, enabling simultaneous T1, T2, T2*, and FF myocardial tissue characterization in a single breathâhold scan. T2* quantification is achieved with an eightâecho readout that requires a long cardiac acquisition window. A novel lowârank motionâcorrected (LRMC) reconstruction is exploited to correct for cardiac motion within the long acquisition window. The proposed T1/T2/T2*/FF cardiac MRF was evaluated in phantom and in 10 healthy subjects in comparison to conventional mapping techniques. RESULTS: The proposed approach achieved high quality parametric mapping of T1, T2, T2*, and FF with corresponding normalized RMS error (RMSE) T1 = 5.9%, T2 = 9.6% (T2 values <100 ms), T2* = 3.3% (T2* values <100 ms), and FF = 0.8% observed in phantom scans. In vivo, the proposed approach produced higher leftâventricular myocardial T1 values than MOLLI (1148 vs 1056 ms), lower T2 values than T2âGraSE (42.8 vs 50.6 ms), lower T2* values than eightâecho gradient echo (GRE) (35.0 vs 39.4 ms), and higher FF values than sixâecho GRE (0.8 vs 0.3 %) reference techniques. The proposed approach achieved considerable reduction in motion artifacts compared to cardiac MRF without motion correction, improved spatial uniformity, and statistically higher apparent precision relative to conventional mapping for all parameters. CONCLUSION: The proposed cardiac MRF approach enables simultaneous, coâregistered mapping of T1, T2, T2*, and FF in a single breathâhold for comprehensive myocardial tissue characterization, achieving higher apparent precision than conventional methods