Abstract Objectives To evaluate the influence of fat on the assessment of liver fibrosis in chronic liver disease using two-point Dixon water-only Look-Locker T1 mapping by comparing water-only derived sequence (W-Dixon) with in-phase (IP) and opposed-phase (OP)-based sequences. Methods 2.89-T MRI included 2D two-point Dixon Look-Locker T1 mapping and proton density fat fraction (PDFF) mapping. The correlations between liver T1 values and PDFF were assessed using Spearman correlation coefficient. T1 values on each T1 map were compared among three FIB-4 index range groups (FIB-4 1.3, 1.3-2.67, 2.67) in patients with and without hepatic steatosis using one-way analysis of variance and Kruskal-Wallis test. Results 204 patients with chronic liver disease were retrospectively evaluated. T1 values on IP or OP images were significantly correlated with PDFF (r = -0.373, 0.220), while no significant correlation was found between T1 values on W-Dixon images and PDFF (r = -0.071). In patients without hepatic steatosis, T1 values on each T1 map in FIB-4 2.67 group were significantly higher than in FIB-4 1.3-2.67 group (p 0.01). Conversely, in patients with hepatic steatosis, only W-Dixon sequence statistically differentiated FIB-4 2.67 group from FIB-4 1.3-2.67 group based on T1 values (p 0.05). Conclusions The assessment of liver fibrosis based on T1 values obtained by Dixon water-only T1 mapping was less influenced by the presence of fat. Advances in knowledge Two-point Dixon water-only Look-Locker T1 mapping minimizes the confounding effect of fat, enabling proper assessment of liver fibrosis in steatotic chronic liver disease.
Higashi et al. (Tue,) studied this question.