Correlations between quantitative parameters of contrast-enhanced ultrasonography and histopathologic stage of liver fibrosis

Objective To investigate the correlations between quantitative parameters of contrast-enhanced ultrasonography(CEUS) and histopathological stage of liver fibrosis.Methods Sixty cases of hepatic fibrosis diagnosed pathologically were examined with CEUS.The dynamic images of CEUS were analyzed off-line with a quantitative software.Region of interest (ROI) were drawn separately in hepatic artery(HA),liver parenchyma(PA),main portal vein(PV) and right hepatic vein(HV).The time intensity curve(TIC) and some quantitative parameters,including arrival time,increased signal intensity(ISI),peak intensity(PI) and area under curve(AUC) were acquired.Intrahepatic transit time of contrast agents were calculated as the arrival time difference between hepatic artery(HA) and HV(HA-HVTT),between PV and HV(PV-HVTT) and between PA and HV (PA-HVTT).All the parameters were compared with histopathologic stage.Results All cases were grouped into mild fibrosis (S0 and S1,25 cases),moderate fibrosis (S2 and S3,17 cases) and severe fibrosis (S4,18 cases) according pathologic stage.HA-HVTT,PV-HVTT and PA-HVTT decreased with the development of liver fibrosis.The parameters of ISI,PI and AUC obtained from TIC of portal vein reduced with the progression of fibrosis,too(P＜0.05).Receive operating characteristic(ROC) curve analysis showed that the area under curve of HA-HVTT,PV-HVTT and PA-HVTT were 0.808,0.848,and 0.823 (S＞S1),and 0.856,0.903,and 0.806 (S＞S3),respectively.Conclusions Quantitative parameters of CEUS reflect the stage of liver fibrosis mediately.The parameters of HA-HVTT,PV-HVTT and PA-HVTT are closely correlated with the stage of liver fibrosis. Key words: Ultrasonography; Microbubbles; Liver cirrhosis