The Value Of Acoustic Radiation Force Impulse Elastography In Differentiating Cirrhotic And Non-cirrhotic Ascites

Objectives: Cirrhosis accounts for 85% of the causes of ascites besides other causes such as malignancy, heart failure, tuberculosis, etc. Ascitic fluid analysis is one of the most important tests to diagnose causes of ascites. However, this is an invasive procedure. Acoustic Radiation Force Impulse (ARFI) is a new measurement of elastography which can diagnose cirrhosis in patients with ascites. This study evaluates the value of ARFI for initial diagnosis of ascites due to cirrhosis or not due to cirrhosis. Materials and methods: Institutional review board approved this cross-sectional study. The study was carried out on 90 patients with ascites. All patients diagnosed with ascites at Nguyen Trai hospital and Clinic of Pham Ngoc Thach University of Medicine were enrolled from January 2013 to October 2018. All patients underwent ARFI and ascitic fluid analysis. Results: The rate of cirrhotic and non-cirrhotic etiology of ascites were 84.4% and 15.6%, respectively The mean liver stiffness measurements by means of ARFI were statistically significantly higher in patients with cirrhotic ascites than in those with non-cirrhotic ascites: 3.84 m/s ± 1.43 v/s 1.48 m/s ± 0.55 (p<0.001). In our study, AUROC had a validity of 92.1% with 95% CI= 0.963–0.982 to diagnose of cirrhotic ascites. For an optimal cut-off value of 2.2 m/s for predicting cirrhosis and ascites in the context of cirrhosis, ARFI had sensitivity of 98%, specificity of 66.7%, positive predictive value of 94.3%, negative predictive value of 85.7% for predicting cirrhotic ascites. Conclusion: ARFI elastography was feasible in all patients with ascites. It had a high performance for diagnosis of cirrhosis (AUROC >0.9) andan effective differentiation between the cirrhotic and non-cirrhotic cause of ascites.