Liver

histology was assessed by experienced histopathologists (B.L.B., P.C.C.) who were blinded to the clinical data. Liver specimens shorter than 15 mm were excluded. Histological scoring was performed according to the system reported by Kleiner et al.19 Grade of steatosis was defined according to Kleiner et al.: 0 = steatosis < 5%, 1 = steatosis 5% to 33%, 2 = steatosis > 33% − 66%, 3 = steatosis > 66%. Fibrosis was staged from 0 to 4: stage 0 = absence of fibrosis; stage 1 = perisinusoidal or portal; stage 2 = perisinusoidal and portal/periportal; stage 3 = septal or bridging fibrosis; and stage 4 = cirrhosis. LSM was performed within 1 week before liver biopsy by using transient elastography according to the instructions and training provided by the manufacturer. Measurements were performed on the right lobe of the liver through intercostal spaces with the patient lying in dorsal decubitus click here with the right arm in maximal abduction. Ten successful acquisitions were performed on each patient. The median value represented the liver elastic modulus. Only cases with 10 successful acquisitions were evaluated. The liver stiffness

was expressed find more in kiloPascal (kPa). The success rate was calculated as the number of successful measurements divided by the total number of measurements. The operators were blinded to all clinical data and the diagnoses of the patients. Statistical tests were performed using the Statistical Package for Social Sciences version 16.0. Continuous variables were expressed as mean ± standard deviation or median (interquartile range [IQR]) as appropriate. Receiver-operating characteristics curves were constructed to assess the overall accuracy of LSM and to see more identify optimal cutoffs. The optimal cutoffs of LSM for F2, F3, and F4 disease were chosen at points with the highest Youden’s index. The relationship between steatosis, NAFLD activity score, BMI, and LSMs was adjusted

by fibrosis stage in a multiple linear regression model. Significant discordance between transient elastography and histology was defined as a difference in fibrosis stage by 2 points or more. In the assessment of discordance, both cutoff values identified in this study and those reported by Yoneda et al.20 were used. Quantitative variables between groups were compared by unpaired t test, Mann-Whitney U test, and one-way analysis of variance followed by Bonferroni test. Categorical variables were compared by chi-squared test or Fisher’s exact test. The area under the receiver operating characteristics curves of different noninvasive tests was compared by the Delong test. All statistical tests were two-sided. Significance was taken as P < 0.05. From May 2003 to April 2009, 309 consecutive patients with NAFLD underwent transient elastography and liver biopsies. A total of 35 patients were excluded because of liver biopsy length less than 15 mm. Twenty-eight (10.