204 GASTROINTESTINAL ENDOSCOPY VOLUME 49, NO. 2, 1999 Biliary strictures can be caused by various inflammatory diseases and benign or malignant bile duct tumors. 1-3 In Asian countries focal strictures of the intrahepatic duct (IHD) are usually associated with IHD stones, 3-6 and these strictures are caused by repeated episodes of cholangitis. 7,8 IHD stric- tures can be caused by parasitic disease such as clonorchiasis. However, in this condition there are usually multiple strictures and dilatation of the peripheral intrahepatic ducts, and the pattern of change is not that of a focal stricture of the IHD. Strictures of the extrahepatic bile duct or the hepat- ic duct bifurcation can be caused by tumors or postinflammatory reactions. These lesions usually cause bile duct obstruction, proximal IHD dilata- tion, and obstructive jaundice. 1,2 Therefore unique clinical features and the morphologic changes in the bile duct are of assistance in the differential diagno- sis of bile duct obstruction. In contrast to the strictures described above, focal or segmental strictures of the IHD without any evi- dence of an IHD stone or parasitic disease often pose diagnostic problems. The stricture site is usually unilateral and segmental. Therefore jaundice does not develop until the later stages of the underlying disease. US or CT can detect the dilated duct proxi- mal to the stricture site, but the detailed anatomy of the stricture will remain obscure. ERCP often fails to delineate the lesion because the stricture obstructs the flow of contrast medium and renders the diseased duct as missing. It is usually impossi- Usefulness of cholangioscopy in patients with focal stricture of the intrahepatic duct unrelated to intrahepatic stones Dong Wan Seo, MD, Myung Hwan Kim, MD, Sung Koo Lee, MD, Seung Jae Myung, MD, Gyeong Hoon Kang MD, Hyun Kwon Ha, MD, Dong-Jin Suh, MD,Young Il Min, MD Seoul, Korea Background: Intrahepatic duct strictures are usually caused by intrahepatic duct stones and cholangitis. However, focal strictures of the intrahepatic duct unrelated to intrahepatic stones often pose diagnostic problems. This study was undertaken to prospectively evaluate the usefulness of percutaneous transhepatic cholan- gioscopy in patients with focal intrahepatic duct stricture and no evidence of a stone. Methods: Seventeen patients with focal strictures of the intrahepatic duct without any evidence of a stone were included. Percutaneous transhepatic cholangioscopic examination including procurement of biopsy specimens was performed after per- cutaneous transhepatic biliary drainage. Results: A histopathologic diagnosis was obtained in all patients (9 adenocarci- nomas, 1 squamous cell carcinoma, 2 hepatocellular carcinomas, 2 adenomas, and 3 benign strictures). Of the 9 patients with bile duct adenocarcinoma, 8 under- went surgery and a curative resection was possible in 7 patients (88%). Five patients (63%) had early-stage bile duct cancer in which cancer invasion was lim- ited to the mucosa or fibromuscular layer and there was no evidence of lymph node metastasis. Conclusions: Percutaneous transhepatic cholangioscopy in patients with focal stricture of the intrahepatic duct unrelated to choledocholithiasis is useful for diag- nosis including the detection of early bile duct cancer. (Gastrointest Endosc 1999;49:204-9.) Received January 27, 1998. For revision June 11, 1998. Accepted August 26, 1998. From the Departments of Internal Medicine, Pathology, and Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea. Reprint requests: Dong Wan Seo, MD, Department of Internal Medicine, Asan Medical Center, 388-1 Pungnapdong, Songpagu, Seoul, 138-736, Korea. Copyright © 1999 by the American Society for Gastrointestinal Endoscopy 0016-5107/99/$8.00 + 0 37/1/94056