The Diagnostic Value And Influencing Factors Of Testing Liver Fibrosis By FibroScan(?)

ObjectiveTo investigate the factors which will influence the success ratio of testing liver fibrosis by FibroScan and to make a preliminary probe into the relationship of the Liver Stiffness Measurement (LSM) by FribroScan and the stage of liver fibrosis and the complications of liver cirrosis.MethodDuring the test, 952 examinees received 1852 times of liver stiffness measurement test. The age, gender, BMI, medical history, Child-Pugh and the complications of liver cirrhosis were recorded and analyzed. Among the 952 cases, 639 are chronic hepatitis B patients (67.1%); 44 are asymptomatic hepatitis B virus carriers (4.6%); 3 are acute hepatitis patients (0.32%); 208 are HBV related cirrhosis patients (21.8%) and 58 are healthys (6.1%).The tests of Liver stiffness measurement: the tests were made according to the user manual of FibroScan (Echosens product from France). The tip of the probe transducer was placed on the skin, between the rib bones at the level of the right lobe of the liver, where liver biopsy always be done. 10 times of valid, consecutive measurements were made and the median value was recorded and used as the representative of liver elastic modulus, expressed in kilopascal (kPa). Only LSM obtained with a success rate of at least 60% and the deviation value lower than 1/3 of the median value were considered reliable.Liver histology: All liver specimens were analyzed by an experienced liver pathologist who was blocked from the results of LSM and clinical data of patients. LB specimens with a length of less than 8 septa were considered as unqualified for fibrosis assessment. Liver fibrosis was staged on a 0-4 scale according to the "Chronic hepatitis pathological changes staging" scoring system.Statistical analysis: We used rank correlation,coefficientof partial correlation,F test,Kruskal-Wallis H,Mann-Whitney U,Intra-class Correlation Coefficient and The receiver operating characteristics curves (ROC curve) in the research. Statistical analysis was accomplished with SPSS v 13.0 statistical package.Results1. The influencing factors and stability of FibroScan(?) measurementTo analyze the effect of the characters of the subjects on FibroScan(?) measure -ment by coefficient of partial correlation. Body mass index was the only factor associated with failure of FibroScan(r=-0.187, P=0. 000). And there is no difference of success rate in different state of the diseases(F=2.025, P=0.088),different sex(r=0. 026, P=0. 27) and different age(r=-0. 043, P=0. 064), different operator's relevant intra group coefficient and the same operator is 0.963and 0.922 respectively. For different subjects of different disease state, operated by the same tester, the test results proved to be equally stable.2. The value of LSM for the diagnosis of liver fibrosisThe diagnostic performance of LSM analyzed by receiver operating character -istics curves (ROC curves) indicated that the area under the ROC curves was large for each fibrosis stage which means the diagnosis value is high. And LSM was correlate to fibrosis stage by rank correlation analysis(r=0. 328, P=0. 000). And liver inflammation(r=0. 039, P=0. 607) and liver steatosis(r= - 0.113, P=0.128) usually did not affect the result of LSM .3. The value of LSM to forecasting the complications of liver cirrhosis.The patient who ever had ascites (z=-5.607,P=0.000) , encephalopathy (z=-2. 391,P=0. 017), alimentary tract hemorrhage(z=-2. 751,P=0. 006) and that had high Child-Pugh scores intended to have high LSM. By observing the patients with high bilirubin, the LSM dropped while bilirubin dropped (r=0.837,P = 0.000).The LSM failed to predict the presence of oesophageal varices and oesophageal varies grade=II(the area under ROC curves is 0.607 and 0.497 respectively) which is not in accordance with relevant reports from abroad. It might be that the amount of subjects of this research is small and most of the patients had very high bilirubin. This might have led to the inaccurate reflection of the degree of liver stiffness compared with the patients with identical fibrosis stage.Conclusions1. The cases studied proved that most of the subjects can get LSM successfully except those with high BMI. The stability of valid liver elasticity measurement is high and the same to the intra-and inter-operator stability of the liver elasticity measurement.2. The LSM from FibroScan have high reference value for the diagnosis of liver fibrosis. Liver steatosis and liver inflammation usually does not affect the result of LSM.3. The patients who ever had ascites, encephalopathy, alimentary tract hemorrhage and that had high Child-Pugh scores intend to get high LSM. However, the researches show that the liver stiffness measurement failed to predict the presence of oesophageal varices and oesophageal varies grade=II which is different from report abroad.