Noninvasive evaluation of hepatic fibrosis stages by contrast enhanced ultrasonography parameters

Objective To discuss the feasibility of non-invasive quantitative evaluation of hepatic fibrosis by contrast-enhanced ultrasonography (CEUS) parameters. Methods CEUS of liver and liver biopsy were performed in 86 patients. CEUS parameters including area under curve of portal vein/hepatic artery(Qp/Qa) ,perfusion intensity of portal vein/hepatic artery(Ip/Ia), decreasing rate of liver parenchyma perfusion (β) and perfusion time of portal vein (Tp) were calculated based on CEUS images. Differences of the four parameters among stages of hepatic fibrosis were analyzed by ANOVA and Spearman rank correlation test was applied to analyze correlation between parameters and hepatic fibrosis stages. Areas under receiver operating characteristic (ROC) curves were calculated to evaluate the diagnostic accuracy of parameters. Results Tp and β had increasing tend while Ip/Ia and Qp/Qa had declining tend from S0 to S4.They were significantly correlated with fibrosis stage( P ＜0.05＝. The areas under ROC curves of Ip/Ia were 0.931 (≥S1) ,0.884(≥S2 ) ,0.820(≥S3 ) and 0.846(S4 ) respectively. The areas under ROC curves of Qp/Qa were 0.914(≥S1),0.813(≥S2),0.845(≥S3) and0.869 (S4) respectively. Conclusions CEUS parameters of liver parenchyma Ip/la, Qp/Qa, Tp and β are related to fibrosis stages. Ip/Ia and Qp/Qa provide a reliable,non-invasive method for evaluating fibrosis stages. Key words: Ultrasonography; Microbubbles; Liver cirrhosis