Effect of Gd-DOTA on fat quantification in skeletal muscle using two-point Dixon technique - Preliminary data

Purpose To assess differences in fat signal fraction (FSF) in skeletal muscle as determined by two-point Dixon technique at 3T before and after application of intravenous gadoterate meglumide (Gd-DOTA). Materials and methods Eight patients (mean age, 50.8 years; range, 41-72 years) underwent clinical whole-body MRI at 3T for myopathic symptoms. Two-point Dixon technique based T1-weighted turbo spin-echo images were acquired before and after the administration of intravenous Gd-DOTA. On both image sets, the FSF was calculated in the gluteus medius, gluteus maximus, and quadriceps muscles bilaterally. Pre- and post-contrast FSF values were compared by linear regression, Bland-Altman plot as well as paired Student t-tests with Bonferroni correction. Results The mean pre- and post-contrast FSF of included muscles were 28.7% ± 14.9% and 27.8% ± 15.1%, respectively. Linear regression indicated almost equivalent FSF estimation between pre- and post-contrast measurements (sum of squared residuals R², 0.92 ± 0.04; slope, 0.97; X-intercept, -0.05; Y-intercept, +0.05). The Bland-Altman plot revealed a minimal systematical bias of the post-contrast FSF measurements of -0.87%. Paired Student t-tests did not reveal significant differences (overall p-value, 0.168). Conclusion Gd-DOTA does not significantly influence FSF quantification in skeletal muscle based on the two-point Dixon technique at 3T.