Wire-guided intraductal US: an adjunct to ERCP in the management of bile duct stones

Background: Endoscopic retrograde cholangiography (ERC) may misdiagnose bil e duct stones if air bubbles are introduced during contrast injection, and it may also fail to diagnose stones in the presence of bile duct dilation. Methods: Our aim was to determine whether intraductal US (IDUS) improves th e accuracy of cholangiography and whether it is a useful adjunct in the man agement of bile duct stones. IDUS with a wire-guided US probe was performed after initial ERC in patients in whom bile duct stones were suspected. The diagnostic accuracy of ERC alone was compared with that of ERC plus IDUS. Results: ERC with IDUS was performed in 62 patients who were suspected to h ave bile duct stones. Both IDUS and ERC were performed by the same endoscop ist, and ERC was performed with a C-arm fluoroscope. The presence of bile d uct stones and/or sludge were confirmed after sphincterotomy and extraction in 34 patients. Overall, the accuracy of ERC combined with IDUS in the dia gnosis of bile duct stone and/or sludge was higher than that of ERC alone ( 97% vs. 87%, p < 0.05). With dilated bile ducts, the diagnostic accuracy of ERC combined with IDUS was also higher than that of ERC alone (95.5% vs, 7 2.7%, p < 0.05). Additional diagnostic information provided by II)US includ ed identification of cystic duct stones in 5 patients, characterization of bile duct strictures in 2 patients, and choledochal varices in 1 patient. P erformance of wire-guided IDUS required 5% of the total procedure time. Conclusions: IDUS improves diagnostic accuracy of ERC and is a useful adjun ct to ERC when bile duct stones are suspected.