Performance of Acoustic Radiation Force Impulse Imaging in Staging Liver Fibrosis and Cirrhosis in Comparison to Serum Fibrosis Markers in Patients with NAFLD

Background: ARFI elastography proved to have excellent performance diagnosing liver cirrhosis and significant fibrosis in viral hepatitis. This study evaluated the diagnostic accuracy of ARFI elastography in different liver segments in overweight and obese patients with non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH). Methods: A total of 89 patients with NAFLD with BMI >24kg/m underwent liver biopsy and liver stiffness (LS) measurement by ARFI elastography in segments 8 and 6. Results: Comparing LS in segment 8 and 6, 10 valid measurements were successful in segment 8 while 5% failure in segment 6. The diagnostic performance of segment 8 and 6 for >!F3 and F4 were 0.99, 0.99, 0.98 and 0.98, respectively. A significant correlation was detected between LS in segment 8 and 6 with the stages of liver fibrosis (p<0.001 and p<0.001, respectively) as well as with NAFLD fibrosis score, FIB-4 and APRI (p=0.004, p=0.041; p<0.001, p<0.001; p<0.001, p<0.001). The discordance between liver biopsy and LS in segment 8 was 5 (6%) and in segment 6 was 4 (5%) and was prominent in (F0-F2). No significant discordance between both segments for the different stages of liver fibrosis. No significant correlation and no significant difference were observed between LS in both segments and the different grades of steatosis or NASH. Conclusions: Liver stiffness (LS) by ARFI elastography is equally successful in several segments of the liver in obese and overweight patients with NAFLD and NASH. An excellent performance was detected for liver cirrhosis and advanced fibrosis and was equally found in the different liver segments in this group of patients.