Noninvasive assessment of macrovesicular liver steatosis in cadaveric donors based on computed tomography liver-to-spleen attenuation ratio.

Fatty liver disease, including liver steatosis, is a major health problem worldwide. In liver transplantation, macrovesicular steatosis in donor livers is a major cause of graft failure and remains difficult to assess. On one hand, several imaging modalities can be used for the assessment of liver fat, but liver biopsy, which is still considered the gold standard, may be difficult to perform in this context. On the other hand, computed tomography (CT) is commonly used by teams managing cadaveric donors to assess donors and to minimize the risk of complications in recipients. The purpose of our study was to validate the use of CT as a semiquantitative method for assessing macrovesicular steatosis in cadaveric donors with liver biopsy as a reference standard. A total of 109 consecutive cadaveric donors were included between October 2009 and May 2011. Brain death was diagnosed according to French legislation. Liver biopsy and then CT were performed on the same day to determine the degree of macrovesicular steatosis. All liver biopsies and CT scans were analyzed in a double-blinded fashion by a senior pathologist and a senior radiologist, respectively. For CT, we used the liver-to-spleen (L/S) attenuation ratio, which is a validated method for determining 30% or greater steatosis in living liver donors. Fourteen of 109 biopsies exhibited macrovesicular steatosis > 30% upon histologic analysis. A receiver operating characteristic curve was generated for the L/S ratio to identify its ability to predict significant steatosis, which was defined as >30%. A cutoff value of 0.9 for the CT L/S ratio provided a sensitivity of 79% and a specificity of 97% to detect significant steatosis.