The aim of this study was to compare the correlations between computed tomography (CT) criteria for hepatic steatosis and lipid profile values when hepatic steatosis is incidentally detected.Participants and methods
This is an institutional Review Board-approved, HIPPA-compliant, retrospective study of abdominal CT scans in 200 randomly selected patients who had either nonenhanced CT (NECT) or contrast-enhanced CT (CECT) studies with reported fatty liver. The participants were matched for age, sex, and ethnicity with 200 patients with nonfatty liver. For NECT, four different criteria have been proposed in the literature to diagnose fatty liver: (i) liver Hounsfield Units (HU) less than 48 HU, (ii) ratio of liver to spleen HU less than 0.8, (iii) HU difference between liver and spleen less than −10, and (iv) hepatic vessel HU greater than or equal to liver HU. For CECT, the criteria was attenuation difference between liver and spleen HU, in the portal venous phase of up to −20 to −25 HU. Laboratory results (low-density lipoprotein, high-density lipoprotein, triglycerides) were documented. Matched analyses and conditional logistic regression analysis were carried out for matched variables.Results
There were statistically significant differences in triglyceride values, between the cases and controls (P=0.02), when all criteria were considered. Also, statistically significant differences were found between cases and controls on the basis of NECT criterion 2 and high-density lipoprotein (P=0.04), as well as CECT criteria and triglyceride levels (P=0.02). In addition, the data indicate that criteria for steatosis on CECT may be more broad than traditionally utilized.Conclusion
Incidental reporting of fatty liver on NECT/CECT should prompt consideration of clinical follow-up and lipid profile testing in an otherwise asymptomatic patient. Additional metrics for the diagnosis of steatosis in CECT exam should also be considered.