title: Mechanism of procedural failure related to wingspan.
abstract: OBJECTIVE
  Wingspan is the only FDA approved self-expanding stent for intracranial artery and known to have better delivery compared to balloon expandable stent. However, some delivery failure has been reported but incidence and mechanism of the failure have not been completely elucidated. We present the cause and mechanism of Wingspan deployment failure experienced in our Institute.
  
  
  METHODS
  We experienced deployment failure in seven patients (8.8%) out of 80 patients who underwent Wingspan stenting since 2007. Mean age of the patients was 62 (range 47~78) and male to female ratio was 6:1. We evaluated the cause and mechanism why the deployment was not successful and how we could manage it subsequently.
  
  
  RESULTS
  WE CATEGORIZED FAILURES OCCURRED IN SEVEN PATIENTS INTO THREE CATEGORIES: delivery failure (n = 3), deployment failure of stent (n = 3), retrieval failure of dual tapered (olive) tip of the inner body through the deployed the stent (n = 1). The technical failure in using Wingspan stent (delivery, deployment and retrieval failures) are related to tortuousness of the proximal (n =4) as well as distal (n =1) cerebral vessels to the stenotic lesion and bulky profile of the olive tip (n =2).
  
  
  CONCLUSIONS
  The technical failure in using Wingspan stent (delivery, deployment and retrieval failures) are related to tortuousness of the proximal as well as distal cerebral vessels to the stenotic lesion and bulky profile of the olive tip. To avoid device-related complication, complete understanding of the stent design is mandatory before using the stent.
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Lin-Bo
authors.initials: LB
authors.lastname: Zhao
authors.forename: Soonchan
authors.initials: S
authors.lastname: Park
authors.forename: Donggeun
authors.initials: D
authors.lastname: Lee
authors.forename: Deok Hee
authors.initials: DH
authors.lastname: Lee
authors.forename: Dae Chul
authors.initials: DC
authors.lastname: Suh