Abstract

Background
/Aims: Covered self-expandable metal stents (CEMS) were developed to overcome tumor ingrowth which is a problem of uncovered EMS (UEMS). However, the efficacy of CEMS is controversial, and CEMS have problems such as migration and development of cholecystitis. Methods: We evaluated 77 cases of endoscopic retrograde biliary drainage using EMS for unresectable distal malignant biliary obstruction in a retrospective setting. Polyurethane-covered Wallstents were used on 36 patients and uncovered Wallstents were used on 41 patients. Early complications and stent patency were analyzed. The end points of this study were stent obstruction or death of the patient. Results: Stent migration occurred in three of the CEMS group and one of the UEMS group. Cholecystitis occurred in one of the CEMS group but in none of the UEMS group. Acute pancreatitis and bleeding did not occur in both groups. Stent occlusion occurred after a mean of 271 days in the CEMS group and 263 days in the UEMS group. Conclusions: Stent patency was comparable between covered and uncovered Wallstent. A large-scale prospective randomized study is needed to evaluate the efficacy and indication of covered Wallstent. (Korean J Gastrointest Endosc 2005;30:257⁣261)

• Keywords: Stents, Biliary tract neoplasms, Biliary obstruction