Diagnosis of liver cirrhosis by transit-time analysis at contrast-enhanced ultrasonography

Purpose. The aims of this prospective study were to evaluate analysis of sulfur-hexafluoride-filled microbubble contrast agent (Sonovue) transit times as a tool for differentiating liver cirrhosis from the noncirrhotic stage of liver disease and to compare its performance with that of conventional B-mode and Doppler ultrasonography (US). Materials and methods. Contrast-enhanced hepatic ultrasonography with the US contrast agent Sonovue was performed on 38 patients with diagnoses of hepatic cirrhosis based on unequivocal clinical signs or liver biopsy findings (Child-Pugh classes A in 19, B in 16 and C in three). 31 patients with noncirrhotic diffuse liver disease (biopsy confirmed) and 14 controls without diffuse liver disease. Time curves of hepatic-vein signal intensity were analysed analysed using objective criteria to determine the time of enhancement onset (hepatic-vein arrival time) and peak enhancement (hepatic-vein peak enhancement). Accuracy in diagnosing cirrhosis was compared with that based oil B-mode and Doppler data. Results. Hepatic-vein arrival time in cirrhotic patients Wits significantly shorter (p < 0.01) than in noncirrhotic (chronic liver disease and controls) patients. Peak enhancement times in these three groups were not significantly different. An arrival-time cutoff of 17 s distinguished cirrhotic from noncirrhotic patients with high accuracy (100% sensitivity, 93.3% specificity, positive and negitive predictive values 92.6% and 100%, respectively)and excellent reproducibility (kappa coefficients of 1.0 and 0.93 for intra- and interobserver agreement). Contrast-enhanced US showed better sensitivity than the B-mode and Doppler data. Conclusions. Analysis of the time of onset of US contrast enhancement of the hepatic vein appears to he a potentially useful noninvasive supplement to conventional sonography and Doppler in the follow-up of patients with chronic diffuse liver disease.