Noninvasive evaluation of liver fibrosis using real-time tissue elastography and transient elastography (FibroScan).

OBJECTIVES: The purpose of this study was to assess liver fibrosis with real-time tissue elastography and to compare the results with those of transient elastographic (FibroScan; Echosens, Paris, France) measurements by using liver biopsy as the reference standard.

METHODS: Real-time tissue elastography and percutaneous liver biopsy were performed in 166 patients with chronic hepatitis B (estimation group). The relationship between the parameters obtained via real-time tissue elastography and the hepatic fibrosis stage was evaluated by a stepwise multiple linear regression, and the regression equation was used to calculate the liver fibrosis index. The diagnostic performance of the liver fibrosis index was validated and compared with FibroScan in 121 other patients with chronic hepatitis B (validation group).

RESULTS: The liver fibrosis index was calculated as follows: liver fibrosis index = 0.043 low-strain area ratio + 4.520 skewness + 0.033 mean - 1.002 kurtosis. The liver fibrosis index and liver stiffness measured by FibroScan were both significantly associated with the fibrosis stage in the validation group (r= 0.667 and 0.664, respectively; both P< .001). The areas under the receiver operating characteristic curves for the liver fibrosis index and liver stiffness were 0.880 and 0.909 for predicting substantial fibrosis (scores ≥F2), 0.868 and 0.874 for predicting severe fibrosis (≥F3), and 0.752 and 0.815 for predicting cirrhosis (F4), respectively.

CONCLUSIONS: Real-time tissue elastography is an effective method for assessing liver fibrosis, with diagnostic performance similar to that of transient elastography.