Accuracy of real-time shear wave elastography for assessing liver fibrosis in chronic hepatitis C: a pilot study

Real-time shear wave elastography (SWE) is a novel, noninvasive method to assess liver fibrosis by measuring liver stiffness. This single center study was conducted to assess the accuracy of SWE in patients with chronic hepatitis C in comparison with transient elastography (TE) by using liver biopsy (LB) as the reference standard. Consecutive patients with chronic hepatitis C scheduled for liver biopsy by referring physicians were studied. One hundred twenty-one patients met inclusion criteria. On the same day real-time SWE using the ultrasound system AixplorerTM (SuperSonic Imagine S.A., Aix-en-Provence, France), TE using FibroScanTM (Echosens, Paris, France) and ultrasound-assisted LB were consecutively performed. Fibrosis was staged according to METAVIR scoring system. Analyses of receiver operating characteristic curve were performed to calculate optimal area under the curve (AUROC) for F0-F1 versus F2-F4, F0- F2 versus F3-F4, and F0-F3 versus F4 for both real-time SWE and TE. Liver stiffness values increased in parallel with the degree of liver fibrosis both with SWE and TE. AUROCs were 0.92 (95%CI,0.85-0.96) for SWE and 0.84 (95%CI,0.76-0.90) for TE (p=0.002); 0.98(95%CI,0.94-1.00) for SWE and 0.96 (95%CI,0.90-0.99) for TE (p=0.14); 0.98(95%CI,0.93-1.00) for SWE and 0.96 (95%CI,0.91-0.99) for TE (p=0.48) when comparing F0-F1 versus F2- F4; F0- F2 versus F3-F4; and F0 -F3 versus F4 respectively. Conclusion. The results of this study show that real-time SWE is more accurate than TE in assessing significant fibrosis (F>2). With respect to TE, SWE has the advantage of imaging liver stiffness in real-time, while guided by a B-mode image. Thus, the region of measurement can be guided with both anatomical and tissue stiffness information.