Liver fibrosis: noninvasive assessment with acoustic radiation force impulse elastography--comparison with FibroScan M and XL probes and FibroTest in patients with chronic liver disease.

PURPOSE To compare the diagnostic performance of acoustic radiation force impulse (ARFI) elastography with that of FibroScan M and XL probes and FibroTest in the staging of fibrosis in patients with chronic liver disease. MATERIALS AND METHODS This study received ethics approval, and all participants provided written informed consent. A total of 321 consecutive patients with chronic liver disease who underwent liver biopsy were prospectively enrolled from April 2010 to May 2012. Liver disease was caused by viral hepatitis (n = 136), alcoholic or nonalcoholic steatohepatitis disorders (n = 113), or some other disease (n = 72). In each patient, liver stiffness was evaluated with ARFI elastography, M and XL probes, and FibroTest within 1 month before liver biopsy. Histologic staging of liver fibrosis served as the reference standard. RESULTS Liver stiffness measurement failure rates were 11.2% with the M probe (36 of 321 patients), 2.3% with the XL probe (six of 260 patients), and 0% with ARFI elastography (0 of 321 patients). Unreliable results with ARFI elastography were more frequent in obese patients (those with a body mass index of 30 kg/m(2) or more) (42 of 86 patients [48.8%] vs 34 of 235 patients [14.5%], P < .0001). No significant difference was found between ARFI elastography and the M probe in the diagnosis of cirrhosis (area under under the receiver operating characteristic curve [Az], 0.88 vs 0.91; P = .12) or severe fibrosis (Az, 0.85 vs 0.89; P = .15); however, the M probe demonstrated better results in the diagnosis of moderate fibrosis (Az, 0.81 vs 0.88; P = .008). No significant difference was found between ARFI elastography and the XL probe in the diagnosis of moderate fibrosis, severe fibrosis, or cirrhosis. The diagnostic performance of ARFI elastography improved when it was applied in nonobese patients (Az of ARFI for cirrhosis and severe fibrosis = 0.92 and 0.91, respectively, in nonobese patients [P = .0002] and 0.63 and 0.63, respectively, in obese patients [P < .0001]). CONCLUSION ARFI elastography is reliable in the assessment of liver fibrosis in patients with chronic liver disease, especially nonobese patients.