Utility of transient elastography in determining liver fibrosis

Abstract

Background:It was a descriptive study to evaluate the accuracy of acoustic radiation force impulse (ARFI) elastography for thedetection of liver fibrosis in patients with diffuse chronic liver diseases (CLD). Materials and Methods: In our study 36 adult healthy volunteers and 65 adult patients with Chronic liver diseases were evaluated using ARFI based US-elastography. Histopathological correlation was done as and when required. Results: ARFI was done in all 36 healthy volunteers and all 65 CLD patients and valid measurements were obtained. The mean shear-wave velocity (SWV) in healthy volunteers was 1.19±0.2 m/s. A gradual increase in mean SWV was noted from fibrosis of Grade F0 to F6 (Ishak's score) and a high positive correlation was found between the mean SWV on A RFI and fibrosis scores at liver biopsy (rho=0.8409). we found statistically significant difference (p<0.001) between the mild (F1 and F2) and significant fibrosis (F3 and F4). The difference in the SWV measurements obtained from consecutive groups (i.e., F1 versus F2, F2 versus F3, and F3 versus F4) was not statistically significant. Using the area under the receiver operating characteristic curve (AUROC), the best calculated cut -off SWVs for the presence of fibrosis (≥F1), significant fibrosis (≥F3), severe fibrosis (≥F4), and cirrhosis (F6) were found to be 1.207, 1.347, 1.513, and 1.92 m/s, respectively. ARFI values were significantly higher in cirrhotic patients than in other patients (p<0.001). Conclusions: ARFI elastography can be used for non-invasive evaluation of liver stiffness and may help to differentiate between no/mild fibrosis and significant fibrosis. Hence when ARFI suggests significant fibrosis the need for liver biopsy may, indeed, be obviated.