Usefulness of Attenuation Imaging with an Ultrasound Scanner for the Evaluation of Hepatic Steatosis.

We investigated the diagnostic capability of the proprietary attenuation imaging (ATI) modality found on some Canon Medical Systems Corp. ultrasound scanners to detect histologically diagnosed steatosis in 148 patients. ATI values increased significantly with increasing steatosis grade (p < 0.001). The diagnostic values (area under the receiver operating characteristic curve) of ATI for steatosis grades ≥ 1 (5%-33% of hepatocytes), ≥ 2 (33%-66% of hepatocytes) and 3 (> 66% of hepatocytes) were 0.85, 0.91 and 0.91. In addition, ATI values increased significantly with increasing steatosis grades (p = 0.002) even in obese patients (n = 41). The diagnostic values of ATI for steatosis grades ≥ 1, ≥ 2 and 3 in obese patients were 0.72, 0.72 and 0.78. Furthermore, ATI values increased significantly with increasing steatosis grade (p < 0.001) in patients with non-alcoholic fatty liver disease (NAFLD) (n = 38). The diagnostic values of ATI for steatosis grades ≥ 1, ≥ 2 and 3 in NAFLD patients were 0.77, 0.88 and 0.86. In conclusion, the ATI method showed good diagnostic capability for the detection of hepatic steatosis.