[Clinical value of acoustic radiation force impulse imaging for quantitative evaluation of degree of liver fibrosis in chronic hepatitis C patients].

OBJECTIVE: To investigate the diagnostic value of acoustic radiation force impulse (ARFI) imaging technology for the assessment of liver fibrosis in chronic hepatitis C (CHC) patients.

METHODS: One-hundred-and-eight CHC patients were examined by real-time ultrasound elastography using the Acuson S2000 ARFI instrument (Siemens Healthcare) and underwent liver biopsy for pathohistological analysis. The correlation between liver fibrosis grades determined by the two approaches was analyzed. The cut-off values for diagnosis by ARFI (S more than 2, S more than 3 and S = 4) were determined by generating a receiver operating characteristic (ROC) curve.

RESULTS: The spectrum of liver stiffness detected by ARFI sonoelastography included S1 at (1.26+/-0.27) m/s (n = 36), S2 at (1.45+/-0.51) m/s (n = 31), S3 at (2.01+/-0.54) m/s (n = 27), and S4 at (2.28+/-0.82) m/s (n = 14). The ARFI values were significantly different among the four different stages of liver fibrosis (P less than 0.001). The liver stiffness detected by ARFI sonoelastography was significantly correlated with the liver fibrosis stage determined by the gold standard pathohistological analysis (Spearman's rank coefficient: 0.61, P less than 0.001). Using the ARFI technology for assessment of liver fibrosis gave areas under the ROC curve of 0.779 for S more than 2 patients, of 0.863 for S more than 3 patients, and of 0.0880 for S = 4 patients.

CONCLUSION: The real-time ultrasound elastography ARFI technology can show the elasticity modulus of liver, and its data values positively correlate with the patho-histology grade of liver fibrosis in CHC patients. ARFI technology is easy to operate, non-invasive, and quantitative, and has potential clinical value for assessing liver fibrosis in CHC.