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Abstract #4552

Implementation of a Robust Method to Derive Unbiased T1 Maps from MOLLI Sequence and Bloch Equations Simulations.

Benjamin Marty1, 2, Alexandre Vignaud3, Andreas Greiser4, Pierre G. Carlier1, 2

1NMR Laboratory, Institute of Myology, Paris, France; 2NMR Laboratory, CEA, I2BM, MIRCen, Fontenay-aux-Roses, France; 3CEA, I2BM, NeuroSpin, Gif-sur-Yvette, France; 4Siemens AG, Erlangen, Germany

The MOLLI sequence has been widely used in CMR protocols for diagnosis and quantification of diffuse myocardial fibrosis but is known to underestimate high T1 values. Bloch equations simulations show that the T1 values derived from MOLLI are quite sensitive to sequence parameters (bSSFP readout scheme, nominal flip angle, inversion efficiency) but also to the tissue T2, using the standard post-processing procedure. In this study, we proposed a robust approach to derive unbiased T1 maps using the simulations, experimental data points of the MOLLI sequence and the acquisition of T2 and B1 maps.

Keywords

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