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Introduction Labile Fe2+ iron is the strongest oxidant in the human organism inducing inflammatory responses and cellular senescence, as well as the transition of fibroblasts and endothelial cells to myofibroblasts, thus, promoting fibrosis as typically occurs in hemochromatosis. On the other hand, as depicted in capillaroscopy images, microvascular damage and extravasation of erythrocytes occur even at the earliest stages of SSc. Such microhemorrhages could lead to erythrocyte-derived iron deposition in surrounding tissues, given that 70% of total body iron is stored in erythrocytes. T2* Magnetic Resonance Imaging (MRI) has emerged as the most reliable and reproducible method for non-invasive assessment of iron deposition in the liver and the heart of hemochromatosis patients. However, quantification of iron in the hands has not been studied. Herein, we examined the feasibility and repeatability of quantitative T2* MRI for the presence of iron in the soft tissues of the fingers in SSc.Material and Methods Ten SSc patients and 10 healthy individuals were studied by MRI examination of both hands using a 1.5T MRI system. Gradient echo (GRE) images with progressively increasing echo times (TE’s) were acquired. After visual inspection of dual-colored maps of the hands, built using an in-house developed software, multiple regions of interest (ROIs) were located at specific areas showing T2* attenuation suggestive of iron presence. Three ROIs per finger with the lowest T2* (ms) values were recorded leading to 30 measurements per individual.Results Mean T2* values for healthy individuals (n=30 per individual) ranged from 12.0 to 16.0 ms (mean±SD: 14.0±2.6 ms) except for a single ROI measurement of 8.8ms in one individual. In contrast, multiple ROIs with T2* values lower than 8.8 ms, considered arbitrarily as the cut-off suggestive of iron deposition, were detected in the fingers of all SSc patients (5-24 areas per patient, mean±SD: 9.7±3.2 ms, p<0.0001 vs healthy). MRI examinations were repeated in 4/10 healthy individuals one year later; again, no areas with T2* below 8.8ms were detected in any of them.Conclusions T2* GRE is a feasible and reproducible technique for the quantification of iron in the soft tissues of the fingers. Studies examining the prognostic value of T2* MRI findings for the assessment of microvasculopathy in the skin as well as in internal organs in SSc patients are underway.Acknowledgments This work is supported by FOREUM and the Bodossaki foundation.