Endoscopic ultrasonography for diagnosing anomalous pancreaticobiliary junction

Background: Anomalous pancreaticobiliary junction (a long common channel) is associated with choledochal cyst or biliary malignancy. We conducted a prospective study to assess the diagnostic value of endoscopic ultrasonography for anomalous pancreaticobiliary junction. Methods: In 188 adult patients with pancreatobiliary disease, the length of the common channel demonstrated by endoscopic ultrasonography was compared with that demonstrated by ERCP. In 25 patients with anomalous pancreaticobiliary junction (the common channel > 15 mm on ERCP), diagnostic accuracy of endoscopic ultrasonography for associated pancreatobiliary diseases was evaluated. Results: On endoscopic ultrasonography, the length of the common channel measured 16.3 +/- 5.8 mm (4 to 27 mm) in patients with anomalous junction; 12 mm or longer in 22 (88%) of 25 patients. In patients with a normal junction, endoscopic ultrasonography demonstrated the channel to be shorter than 7 mm. Endoscopic ultrasonography detected choledochal cyst (in 19 patients), gallstones (in 7), and acute pancreatitis (in 2). This imaging precisely differentiated gallbladder lesions, including carcinoma (4 patients) and mucosal hyperplasia (10 patients) in 14 of 16 patients. Endoscopic ultrasonography could be performed safely in outpatients. Conclusions: Endoscopic ultrasonography is a useful imaging method for patients with suspected anomalous pancreaticobiliary junction.