Evaluation of liver fibrosis by transient elastography using acoustic radiation force impulse: comparison with Fibroscan(®).

BACKGROUND: Accurate evaluation of liver fibrosis in patients with chronic liver damage is required to determine the appropriate treatment. Various approaches, including laboratory tests and transient elastography, have been used to evaluate liver fibrosis. Recently, transient elastography with acoustic radiation force impulse (ARFI) has been developed and applied with conventional ultrasonography. The aim of this study was to evaluate the clinical utility of transient elastography with ARFI and to compare the results with this method and those of the Fibroscan(®) procedure.

METHODS: One hundred and thirty-one patients with liver damage, who underwent liver biopsy at our department, were enrolled prospectively in this study. Elastography with ARFI (applied with ACUSON S2000(®)), and Fibroscan(®) was performed at the same time as liver biopsy. These measurements were compared with histological findings in liver biopsy specimens, and measurement accuracy was evaluated by receiver-operating characteristic analysis.

RESULTS: Elastography values with both procedures were significantly correlated with the stages of liver fibrosis and there was little difference in the results obtained using the 2 procedures. The accuracy of differential diagnosis between no fibrosis at F0 and more than F1 stage was insufficient with ARFI, but this procedure was sufficient for diagnosing advanced fibrosis. The accuracy of ARFI was almost equivalent to that of the Fibroscan(®) method. Moreover, both ARFI and Fibroscan(®) values increased in proportion to the severity of hepatic inflammation when fibrosis stage is low, but not in proportion to the severity of steatosis.

CONCLUSIONS: Transient elastography with ARFI is simple, non-invasive and useful for diagnosing the stage of fibrosis in chronic liver disease. The utility of ARFI was almost equivalent to that of the Fibroscan(®) method.