CT images obtained at the navel level demonstrating the method used to determine abdominal fat distribution. (a) The line (arrowed) outlines the intraperitoneal area. (b) The line (arrowed), drawn with a cursor automatically or manually, outlines the subcutaneous fat layer, in which attenuation is measured. (c) A histogram of the CT numbers (in Hounsfield units) in the area outlined in b (mean ± 2 SD). (d) Measurement of visceral fat tissue (solid arrow). The total fat area is represented by the region outlined by the circumference of the abdominal wall. The visceral fat area was subtracted, and the remainder was regarded as the subcutaneous fat area (dotted arrow).