Fig 1. A 14-year-old boy with obesity (body mass index, 28.9 kg/m²) and fatty liver.

From the liver MRI, (A) fat fraction of the liver (18%) was obtained from oval or circular region-of-interest (ROI, yellow circle) in the right lobe on the fat map. (B) The ROIs (yellow circles) for paraspinal muscle fat fraction were drawn bilaterally at the level of mid L2 and the mean value was 3.2% in this case. (C) In order to measure the psoas muscle area (PMA), free hand ROIs (yellow lines) were drawn at the level of mid L3 on T2-weighted axial images. The PMA was 1197.7 mm² and the z-score of PMA was -2.56 in this patient.