title: A comparative analysis of PTFE-covered and uncovered stents for palliative treatment of malignant extrahepatic biliary obstruction.
abstract: OBJECTIVE
  The purpose of our study was to evaluate the outcomes of the newly designed partially polytetrafluoroethylene (PTFE)-covered stent and compare the outcomes of PTFE-covered and uncovered stents in patients with malignant extrahepatic biliary obstruction.
  
  
  METHODS
  From March 2006 to December 2008, 58 consecutive patients who underwent PTFE-covered stent placement were prospectively studied. Those data were compared with data obtained by retrospectively studying 58 consecutive patients who underwent self-expanding uncovered stent placement from March 2003 to February 2006.
  
  
  RESULTS
  According to the Kaplan-Meier analysis, the cumulative stent patency of covered stents (98%, 98%, 91%, 76%, and 76% at 1, 3, 6, 9, and 12 months, respectively) was significantly better than that of uncovered stents (98%, 83%, 72%, 57%, and 57% at 1, 3, 6, 9, and 12 months, respectively) (p = 0.037). There was no significant difference in the patient survival between the groups (p = 0.479). The two groups also did not significantly differ in terms of complication rate (p = 0.717), with 8.6% (5/58) in the covered stent group and 5.2% (3/58) in the uncovered stent group.
  
  
  CONCLUSIONS
  Partially PTFE-covered stents are effective and safe for the palliative treatment of malignant extrahepatic biliary obstruction. Moreover, PTFE-covered stents were significantly superior to uncovered stents in terms of stent patency for palliative treatment of patients with malignant extrahepatic biliary obstruction. In addition, there was no significant difference in patient survival and complication rate between the PTFE-covered and uncovered stent group.
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, 86, Asanbyeongwon-gil, Songpa-gu, Seoul, 138-736 Korea. radgwon@amc.seoul.kr
authors.forename: Dong Il
authors.initials: DI
authors.lastname: Gwon
authors.forename: Gi-Young
authors.initials: GY
authors.lastname: Ko
authors.forename: Jin Hyoung
authors.initials: JH
authors.lastname: Kim
authors.forename: Hyun-Ki
authors.initials: HK
authors.lastname: Yoon
authors.forename: Im Sick
authors.initials: IS
authors.lastname: Lee
authors.forename: Kyung-Ah
authors.initials: KA
authors.lastname: Kim
authors.forename: Kyu-Bo
authors.initials: KB
authors.lastname: Sung
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001650:Bile Duct Neoplasms / Q000628:therapy*; D001651:Cholestasis, Extrahepatic / Q000628:therapy*; D020099:Coated Materials, Biocompatible; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010166:Palliative Care / Q000379:methods*; D011138:Polytetrafluoroethylene; D011446:Prospective Studies; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D015607:Stents; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D020099:Coated Materials, Biocompatible; D011138:Polytetrafluoroethylene