Abstract:
:The assessment of myocardial fibrosis and extracellular volume requires accurate estimation of myocardial T1 s. While image acquisition using the modified Look-Locker inversion recovery technique is clinically feasible for myocardial T1 mapping, respiratory motion can limit its applicability. Moreover, the conventional T1 fitting approach using the magnitude inversion recovery images can lead to less stable T1 estimates and increased computational cost. In this article, we propose a novel T1 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 T1 fitting resulting in improved quality of the T1 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 T1 fitting, the proposed phase-sensitive method leads to less fluctuation in T1 estimates.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Xue H,Greiser A,Zuehlsdorff S,Jolly MP,Guehring J,Arai AE,Kellman Pdoi
10.1002/mrm.24385subject
Has Abstractpub_date
2013-05-01 00:00:00pages
1408-20issue
5eissn
0740-3194issn
1522-2594journal_volume
69pub_type
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