Stability of FibroTouch in determining liver stiffness measurement and controlled attenuation parameter

Objective To investigate the stability of FibroTouch(FT) in the determination of liver stiffness measurement(LSM) and controlled attenuation parameter(CAP). Methods A total of 309 patients with chronic hepatitis B virus(HBV) infection,nonalcoholic fatty liver disease(NAFLD),liver function abnormalities,or other diseases who underwent FT in the outpatient service of Department of Hepatology,The Second Affiliated Hospital of Anhui Medical University,were enrolled. FT was performed at three different measurement points for the same subject,and intraclass correlation coefficient(ICC) and the Bland-Altman method were used to evaluate the stability of measured values. The Kendall's W test and pie charts were used to evaluate the stability of diagnostic results. Results LSM and CAP values of the three different measurement points for the same subject had an ICC of > 0. 75 in different disease groups(all P < 0. 001),among which the chronic HBV infection group had the highest ICC of LSM of 0. 905,the other disease group had the highest ICC of CAP of 0. 805,the NAFLD group had the lowest ICC of LSM of 0. 785 and the lowest ICC of CAP of 0. 780. The Bland-Altman plots were generated for the three measurement points,and the dots within the limits of agreement accounted for about 95%. The diagnostic results of LSM and CAP staging of the three measurement points had a Kendall's W coefficient of 0. 825 and 0. 858,respectively(all P < 0. 001). The proportion of patients with consistency between the diagnostic results for F≥2 stage(LSM > 7. 3 k Pa) and mild(or more severe) fatty liver stage(CAP >240 dB/m) based on mean value of measurement points and all three measurement points was > 60%,while the proportion of patients with consistency between the diagnostic results based on mean value of measurement points and only one measurement point was < 10%. Conclusion The values and diagnostic results of FT measurement have good stability; however,in order to improve its stability in diagnosing F ≥2 stage and mild(or more severe) fatty liver,it is suggested to use the mean value of multiple measurement points for diagnosis.