Dr Hirche and colleagues from Germany compared 2 alternative ultrasound methods in patients with Hepatitis C.
The techniques included hepatic vein flow pattern and presence of focal hypoechoic areas within the liver hilus as non-invasive predictors of liver steatosis in these patients.
The team assessed 122 consecutive patients with chronic Hepatitis C infection.
The Hepatic vein flow pattern, and presence of hypoechoic areas within the liver hilus were evaluated by Duplex-Doppler and B-mode sonography.
|Combination of both sonographic tests resulted in an improved sensitivity of 82%|
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.
The research team evaluated the association of fatty infiltrations with clinical and sonographic features by a stepwise logistic regression analysis.
The researchers found that reduced hepatic vein flow and hypoechoic areas strongly correlated with steatosis on histology.
However, standard clinical and laboratory parameters did not correlate with steatosis on histology.
Both sonographic parameters made excellent predictions for the subgroup of patients with severe steatosis, particularly when both tests were combined.
The sensitivity, specificity, positive predictive value, and accuracy was 95%, 96%, 93%, and 96%, respectively.
However, the sensitivity and accuracy of hepatic vein flow pattern analysis were markedly reduced when all degrees of steatosis were defined as positive.
The sensitivity, specificity, positive predictive value, and accuracy was 71%, 76%, 81%, and 73%, respectively, when all categories were defined as positive.
In contrast, the team noted that the dichotomous parameter hypoechoic areas remained a powerful indicator even under the latter conditions.
The combination of both sonographic tests resulted in an improved sensitivity of 82%.
However, the combination of the tests lead to a significant loss of specificity of 76%, and accuracy down to 80% for prediction of liver steatosis.
Dr Hirche's team concluded, "Sonographic evaluation of reduced hepatic vein flow and hypoechoic areas 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."