Model-free phasor image analysis of quantitative myocardial T1 mapping

• Published in: Scientific reports Vol. 12; no. 1; pp. 19840 - 10
• Main Authors: Franssen, Wouter M. J., Treibel, Thomas A., Seraphim, Andreas, Weingärtner, Sebastian, Terenzi, Camilla
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 18.11.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 631/1647/245/1627; 631/1647/245/1628; 631/1647/245/2225; 631/57; 692/308; 692/4019; Data processing; Dimensional analysis; Feasibility studies; Humanities and Social Sciences; Image processing; Lifetime; Magnetic resonance imaging; Mapping; multidisciplinary; Myocardium; Science; Science (multidisciplinary)
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-022-23872-9

Model-free phasor image analysis, well established in fluorescence lifetime imaging and only recently applied to qMRI T 2 data processing, is here adapted and validated for myocardial qMRI T 1 mapping. Contrarily to routine mono-exponential fitting procedures, phasor enables mapping the lifetime information from all image voxels to a single plot, without resorting to any regression fitting analysis, and describing multi-exponential qMRI decays without biases due to violated modelling assumptions. In this feasibility study, we test the performance of our recently developed full-harmonics phasor method for unravelling partial-volume effects, motion or pathological tissue alteration, respectively on a numerically-simulated dataset, a healthy subject scan, and two pilot patient datasets. Our results show that phasor analysis can be used, as alternative method to fitting analysis or other model-free approaches, to identify motion artifacts or partial-volume effects at the myocardium-blood interface as characteristic deviations, or delineations of scar and remote myocardial tissue in patient data.