Fig. 1From: Usefulness of peroral cholangioscopy in the differential diagnosis of IgG4-related sclerosing cholangitis and extrahepatic cholangiocarcinoma: a single-center retrospective studyCholangioscopic images of IgG4-related sclerosing cholangitis. a Stricture in the middle and hilar bile duct. b Dilated and tortuous vessels spreading around the stricture with smooth mucosal surface. c Stricture in the intrapancreatic bile duct. d Stricture with edematous and smooth mucosal surfaceBack to article page