Real-time elastography for noninvasive assessment of liver fibrosis in chronic viral hepatitis

OBJECTIVE. Recently, transient elastography (FibroScan) has been introduced for noninvasive staging of liver fibrosis. Here, we investigated a novel approach for noninvasive assessment of liver fibrosis using sonography-based real-time elastography, which can be performed with conventional ultrasound probes during a routine sonography examination. MATERIALS AND METHODS. Real-time elastography was performed in 79 patients with chronic viral hepatitis and known fibrosis stage and in 20 healthy volunteers. A specially developed program was used for quantification of tissue elasticity. Stepwise logistic regression analysis was performed to define an elasticity score using variables with high reproducibility in a preceding analysis of data from 16 different patients. In addition, aspartate transaminase-to-platelet ratio index (APRI) and routine laboratory values were included in the analysis. RESULTS. The Spearman's correlation coefficient between the elasticity scores obtained using real-time elastography and the histologic fibrosis stage was 0.48, which is highly significant (p < 0.001). The diagnostic accuracy expressed as areas under receiver operating characteristic (ROC) curves were 0.75 for the diagnosis of significant fibrosis (fibrosis stage according to METAVIR scoring system [F] >= F2), 0.73 for severe fibrosis (F >= F3), and 0.69 for cirrhosis. For a combined elasticity-laboratory score, the areas under the ROC curves were 0.93, 0.95, and 0.91, respectively. DISCUSSION. Real-time elastography is a new and promising sonography-based noninvasive method for the assessment of liver fibrosis in patients with chronic viral hepatitis.