ABSTRACT
PURPOSE: To evaluate the efficacy of attenuation measurement function (ATT), a newly developed quantitative ultrasonography(US) method based on measurement of the attenuation coefficient, using unenhanced computerized tomography(CT) attenuation values as a reference standard, for the detection and measurement of hepatosteatosis. MATERIAL AND METHODS: A total of 98 patients were analyzed. The diagnostic ability of ATT was evaluated using receiver operating characteristic (ROC) curve analysis, and the correlation between liver attenuation index (LAI), the liver-to-spleen attenuation ratio (CTL/S), liver attenuation value (CTL), and ATT was determined. RESULTS: ATT is negatively correlated with LAI (r = -0.571, p < 0.001), CTL/S (r = -0.532, p < 0.001), and mean CTL (r = -0.50, p < 0.001). A significant difference was found between ATT values of patients with different grades of hepatosteatosis (p < 0.001). A significant difference was found between ATT values of patients with LAI < -10 and LAI > -10, CTL < 40 and CTL > 40, and CTL/S < 1 and CTL/S > 1 (p < 0.001). An ATT ≥ 0.665 showed a sensitivity of 100% and a specificity of 90% in diagnosing moderate-severe steatosis. The corresponding area under the ROC curve(AUROC) was 0.935. The intraclass correlation coefficient for the interobserver variability of ATT was 0.907 (95% CI, 0.85-0.95). CONCLUSION: In conclusion, ATT values for evaluation of hepatosteatosis was closely correlated with the degree of hepatosteatosis and liver fat content. It can be used as a noninvasive method in the diagnosis and follow-up.
