Evaluation of hepatic steatosis by ultrasound in patients with chronic hepatitis C virus infection.
OBJECTIVE
To compare two alternative ultrasound parameters, hepatic vein flow (HVF) pattern and presence of focal hypoechoic areas (FHA) within the liver hilus, as non-invasive predictors of liver steatosis in patients with chronic hepatitis C virus (HCV) infection.


METHODS
In 122 consecutive patients with chronic HCV infection, the HVF pattern and presence of FHA within the liver hilus were assessed by Duplex-Doppler and B-mode sonography. All patients underwent liver biopsy and the sonographic results were compared with a histological score of steatosis used as the gold standard for this purpose. Association of fatty infiltrations with clinical and sonographic features were evaluated by a stepwise logistic regression analysis.


RESULTS
Reduced HVF and FHA, but not standard clinical and laboratory parameters, strongly correlated with steatosis on histology (P<0.001). Both sonographic parameters made excellent predictions for the subgroup of patients with severe steatosis, particularly when both tests were combined [sensitivity (SE) 95%, specificity (SP) 96%, positive predictive value (pPV) 93%, negative predictive value (nPV) 97%, and accuracy 96%]. However, the sensitivity and accuracy of HVF pattern analysis were markedly reduced when all degrees of steatosis were defined as positive (SE 71%, SP 76%, pPV 81%, nPV 64%, and accuracy 73%). In contrast, the dichotomous parameter FHA remained a powerful indicator even under the latter conditions (SE 74%, SP 100%, pPV 100%, nPV 72%, and accuracy 84%). The combination of both sonographic tests resulted in improved sensitivity (82%), but significant loss of specificity (76%) and accuracy (80%) for prediction of liver steatosis.


CONCLUSIONS
Sonographic evaluation of reduced HVF and FHA within the liver hilum is easy to perform, non-invasive, and, when present, gives a high degree of confidence in the diagnosis of liver steatosis. However, the lack of sonographic evidence of steatosis cannot definitively exclude the presence of mild steatosis, as shown on biopsy.
Hirche
T O
TO
Department of Internal Medicine I, University Hospital Frankfurt, Frankfurt am Main, Germany.
Ignee
A
A
Hirche
H
H
Schneider
A
A
Dietrich
C F
CF
D000328:Adult; D001706:Biopsy; D001783:Blood Flow Velocity; D005234:Fatty Liver / Q000000981:diagnostic imaging* / Q000473:pathology / Q000821:virology; D005260:Female; D006503:Hepatic Veins / Q000000981:diagnostic imaging* / Q000503:physiopathology; D019698:Hepatitis C, Chronic / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D008099:Liver / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000473:pathology / Q000821:virology; D008102:Liver Circulation; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018616:Ultrasonography, Doppler, Duplex