Fig. 2. MRS (A, B) and MRI-proton density fat fraction (C) results of a patient with hepatic steatosis.

A. A 3 × 3 × 3 cm-sized voxel was placed in the right hepatic lobe for MRS. B. The MRS frequency spectrum (upper) at the voxel shows a large water peak at 4.7 ppm as well as multiple lipid peak areas at a lower ppm. Fat and water signals at different TEs are plotted (lower), and the T2-corrected fat signal fraction is calculated by 29.3%. C. Fat signal fraction map acquired with multi-echo Dixon MRI in the same patient: brighter areas indicate higher fat signal fraction. A 2 cm-sized circular ROI is placed in the right hepatic lobe, and the fat signal fraction for the ROI was calculated as 24.4%. MRS = MR spectroscopy, ROI = region of interest, TE = echo time