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Abstract #2400

Effects of Phase Alternations in Nonlinear Inverse T2 Reconstructions from Undersampled Data

Tilman Johannes Sumpf1, Amir Moussavi1, 2, Martin Uecker1, 3, Susann Boretius1, 4, Jens Frahm1

1Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut fuer biophysikalische Chemie, Goettingen, Germany; 2DFG Research Center for Molecular Biology of the Brain (CMPB), Goettingen, Germany; 3Electrical Engineering and Computer Science, University of California, Berkeley, United States; 4Klinik fr Diagnostische Radiologie, Universittsklinikum Schleswig-Holstein, Kiel, Germany

Quantitative evaluation of the T2 relaxation time is of high importance for diagnostic MRI. Standard T2 mapping procedures rely on the time-demanding acquisition of several fully-sampled k-space data sets. We recently evaluated a new method that allows for the reconstruction of spin-density and T2 maps from highly undersampled Cartesian data by exploiting data redundancy in parameter space. However, the effect of periodic phase alternations due to unavoidable motion in in-vivo experiments can cause severe artifacts in reconstructions from undersampled data. This work explains the origin of these artifacts and demonstrates the impact on reconstructions from undersampled high-field animal MRI data.

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Keywords

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