A study was conducted on a group of 50 obese females with a mean body mass index of 39 +/- 16, aged 19 years, in order to determine if sonography could be adopted as a direct means for measuring intra-abdominal fat deposits. Adipose tissue evaluation was performed by computed tomography (CT) and ultrasonography (using 3.5-MHz and 5-MHz probes) at the L4 level. CT intra-abdominal fat area (VAT) and ultrasonography visceral thickness from abdominal muscle to aorta were the values mainly considered. Ultrasonographic intra-abdominal thickness correlated well with VAT (r = 0.669, p less than 0.001), supporting the hypothesis that ultrasonography could be useful in the direct evaluation of intra-abdominal fat deposits.