A comparative study of FibroScan and B ultrasound in diagnosis of liver fibrosis

Objective To compare the diagnostic performances of FibroScan ( FS) and B ultrasound for liver fibrosis and assess the relationship between the two methods. Methods The clinical data of 432 patients who were admitted to our institution between October 2012 and February 2014 were retrospectively analyzed. Of them, 305 had chronic hepatitis B virus infection, 96 had chronic hepatitis C virus infection, and 31 had primary biliary cirrhosis. FS values and parameters measured by B ultrasound including the thickness of left and right liver lobes, the diameter of the portal vein, spleen thickness, spleen length, the diameter of the splenic vein, and variables describing vascular morphology of the liver were recorded. Additionally, the incidence rates of ascites, fatty liver disease, gallbladder diseases, and liver cirrhosis were also reviewed. The correlations between FS value and the parameters were explored using the Spearman rank correlation test and multiple linear regression model. Patients were categorized based on FS values; parameters were compared between the groups by use of Kruskal-Wallis H test or Mann-Whitney U test. Results FS value was positively correlated with the thickness of left liver lobe, spleen thickness and length, the diameter of the portal vein, the diameter of the splenic vein, liver surface smoothness, parenchymal echo, vascular morphology, ascites ( presence or absence) , and liver cirrhosis ( presence or absence) ( rs= 0. 249-0. 543, P < 0. 05 for all) . Furthermore, positive correlations were also observed between these parameters and the stage of liver fibrosis as determined based on FS values ( rs= 0. 229-0. 541, P < 0. 05 for all) . Multiple linear regression analysis identified liver surface smoothness, thickness of the left liver lobe, ascites, and diameter of the portal vein as independent predictive factors for FS value ( t = 5. 123, 3. 703, 3. 113, and 2. 985, P <0. 05 for all) . FS values were 9. 573 ± 9. 490 kPa, 16. 339 ± 11. 359 kPa, and 27. 688 ± 18. 676 kPa in the three groups with liver echo enhancement, rough echo, and nodular echo, respectively; differences between the groups were significant ( χ2= 98. 469, P = 0. 000) .Conclusion There are reliable correlations between FS value and parameters measured by B ultrasound. The diagnostic performance of FibroScan for liver fibrosis is more accurate and objective than that of B ultrasound.