A case of successful removal of a migrated fish bone in the bile duct after pancreaticoduodenectomy using overtube-assisted cholangioscopy.

Fish bone migration into the bile duct in patients with surgically altered anatomy is a very rare cause of bile duct stones. Recently, balloon-assisted endoscopic retrograde cholangiopancreatography (BAERCP) is performed for biliary lesions in patients with surgically altered anatomy. We report on a 73-year-old Japanese man with a history of pancreaticoduodenectomy for intraductal papillary mucinous adenoma. A 20 mm long linear hyperattenuating structure in the left intrahepatic bile duct was noted on routine follow-up computed tomography 14 years postoperatively. The linear structure persisted until follow-up computed tomography performed 15 years postoperatively, and the left intrahepatic bile duct was shown to be dilated. We performed BAERCP for the diagnosis and treatment of the linear structure but could not visualize the linear structure in the left intrahepatic bile duct via enteroscopy and fluoroscopy. We removed the enteroscope, leaving the overtube, and inserted the cholangioscope through the overtube over the guide wire. We observed a brown rod-shaped linear structure in the left intrahepatic bile duct and removed it under direct visualization via overtube-assisted cholangioscopy. We conclude that overtube-assisted cholangioscopy was useful for assessing undiagnosed biliary lesions using conventional BAERCP and removing fish bones in the bile duct of the patient with altered gastrointestinal anatomy.