Comparative study between two 2D-Shear Waves Elastography techniques for the non-invasive assessment of liver fibrosis in patients with chronic hepatitis C virus (HCV) infection

Abstract
Aims: We aimed to compare the diagnostic performance of two 2D-Shear Wave Elastography (2D-SWE) techniques for the non-invasive assessment of liver fibrosis in patients with chronic hepatitis C virus (HCV) infection using Transient Elas-tography (TE) as reference. Material and methods: We enrolled 208 consecutive patients with chronic HCV infection, in which liver stiffness (LS) was evaluated in the same session using two 2D-SWE techniques: 2D-SWE.GE and 2D-SWE.SSI using TE as the method of reference. LS measurements were considered failures when no value was obtained after 10 attempts. Results: Valid LSMs were obtained in 95.6% (199/208) of cases by 2D-SWE.GE, 92.7% (193/208) of cases by 2D-SWE.SSI, and in 94.7% (197/208) of cases by TE (p>0.05). The mean LS values by 2D-SWE.GE were significantly lower than those obtained by 2D-SWE.SSI: 10.3±3.8 kPa vs. 15±10.4 kPa (p<0.0001). 2D-SWE.GE LSMs correlated better with TE than 2D-SWE.SSI (r=0.75, p<0.0001 vs. r=0.57, p<0.0001, z test p=0.0012). Linear regression analysis showed a moderate correlation between LSMs obtained by 2D-SWE.GE and 2D-SWE.SSI (r=0.63, R2=0.4, P<0.0001). Pairwise comparison of receiver operating characteristics curves (ROC) found no significant differences between 2D-SWE.GE and 2D-SWE.SSI in identifying F≥2 fibrosis (0.97 vs. 0.96, P = 0.5650), F≥3 (0.97 vs. 0.95, P = 0.2935), or F=4 (0.97 vs. 0.96, p = 0.6914). Conclusions: Both 2D-SWE techniques had good feasibility for the noninvasive assessment of liver fibrosis. LS values obtained by 2D-SWE.GE were significantly lower than those obtained by 2D-SWE.SSI. No significant differences were found between both methods in staging liver fibrosis in patients with chronic HCV.