To assess the efficacy of elastmetry in the determination of fibrotic stage in the liver, we investigated correlation between liver histology and the elastometry using a device equipped with a vibrator and an ultrasound system (Echosens, Paris, France) in patients with chronic hepatitis C. Totally 75 patients, 24 in F1 stage, 17 in F2 stage, 18 in F3 stage, and 16 in F4 stage according to the new Inuyama classification without fatty change were investigated. Correlations between the staging of liver fibrosis and elastometry, serum fibrosis makers and platelet counts were investigated. The elastometry was absolutely non-invasive. Serum fibrosis markers did not well correlate with the stage of liver fibrosis. Platelet counts significantly ( [Formula: see text] ) correlated with the fibrotic stage. Median platelet counts in each stage was; F1, 191.5; F2, 172.0; F3, 132.0; F4, 77.5 (x10(3)microl(-1)). However, the deviation was comparatively broad. On the contrary, the elastometry correlated well to the stage of fibrosis and the deviation was small. Median elastometric levels in each stage were; F1, 6.25; F2, 7.80; F3, 13.85; F4, 34.00 (kPa). These results suggest that elastometry is significantly useful for evaluating fibrotic staging of the liver without any invasiveness.