The Assessment of Hepatosteatosis in Living-Donor Liver Transplant: Comparison of Liver Attenuation Index and Histopathologic Results.

Objectives: The purpose of the study was to determine the diagnostic value of computed tomography densitometry in the quantification of hepatosteatosis.

Materials And Methods: Fifty-one potential liver donors, ranging in age from 19 to 52 years (mean age: 32.4 years ± 10.2), participated in the study. The mean hepatic attenuation and mean splenic attenuation were determined using regions of interest measurements. The difference between the mean hepatic attenuation and mean splenic attenuation (or liver attenuation index), with liver attenuation index = mean hepatic attenuation - mean splenic attenuation were calculated. Computed tomography densitometric parameters were correlated with histopathologic results.

Results: From the histopathologic analysis, the degree of macrovesicular hepatosteatosis was 0% to 8% (mean: 1.1% ± 2%). Seven donors (13.7%) had a degree of macrovesicular steatosis of > 5%, and 12 donors (23.5%) had ≥ 2%. Of the 29 normal donors with histopathologic verification, computed tomography densitometry predicted ≤ 5% of the hepatosteatosis in 27 donors, and ≤ 2% hepatosteatosis in 2 subjects. The liver attenuation index was significantly correlated to the histopathologic results. The mathematical relation between liver attenuation index and the degree of histopathologic hepatosteatosis was calculated using the least-squares methods, which provided quadratic polynomials.

Conclusions: Computed tomography densitometry is a rapid, robust, noninvasive technique for the assessment of hepatosteatosis. When used in conjunction with clinically stable reference measurements of spleen, the density measurements of liver correctly predicted the presence of fatty infiltration with significant sensitivity (77%) and specificity (75%). This technique, which was refined during the course of our liver transplant program, minimizes the need for highly invasive percutaneous liver biopsies.