Liver stiffness measured with two-dimensional shear wave elastography comparable to histopathology falls dominantly on the severe liver fibrosis.

Abstract

Two-dimensional shear-wave elastography (2D-SWE) has been used for years for liver assessment of patients with chronic hepatitis B (CHB), but its effectiveness remains unclear in different populations and using different ultrasound systems. This study investigated the effectiveness of 2D-SWE in evaluating liver fibrosis in patients with CHB. A prospective investigation was conducted after approval by the institutional ethics committee, with 116 out of 133 patients with CHB referred for liver biopsy included and 50 patients with healthy livers selected as controls. Assessment with 2D-SWE of liver stiffness measurement (LSM) was compared with histopathological results. Cutoff values for LSM were set to determine the degree of fibrosis, and area under the receiver operating characteristic (AUROC) curve, sensitivity, and specificity were calculated. The optimal LSM cutoff for differentiating healthy livers from livers with CHB and any liver fibrosis was 6.485 kPa, with an AUROC of 0.927, sensitivity of 94%, and specificity of 19.8%. The optimal LSM cutoff values for F1, F2, F3, and F4 were 6.19 kPa, 6.485 kPa, 7.46 kPa, and 9.62 kPa, respectively, with corresponding AUROCs of 0.516, 0.625, 0.779, and 0.881, respectively. Comparisons of AUROCs between F1 and F3, F1 and F4, F2 and F3, and F2 and F4 were all significantly different (P = 0.0001, P < 0.0001, P = 0.0139, and P = 0.0003, respectively); comparisons of AUROCs between F1 and F2 and between F3 and F4 were not significantly different (P = 0.1232 and P = 0.2462, respectively). Comparisons of LSMs between healthy livers and F0 and between healthy livers and a combination of F0 and F1 were significantly different (P = 0.002 and P = 0.001, respectively). Comparisons of LSMs between F1 and F2 and between F3 and F4 were not significantly different (P = 0.233 and P = 0.072, respectively). Other comparisons between fibrosis score groups were significantly different (F1 and F3, P = 0.003; F1 and F4, P = 0.007; F2 and F3, P = 0.013; F2 and F4, P = 0.015). 2D-SWE using a specific diagnostic ultrasound system is effective for the assessment of severe liver fibrosis and cirrhosis, but is limited in diagnosing mild liver fibrosis.