title: Pathophysiology of proximal perigraft endoleak following endovascular repair of abdominal aortic aneurysms: a study using a flow model.
abstract: OBJECTIVE
  to design a flow model to determine whether and why increased proximal neck angulation correlates with increased risk of proximal perigraft endoleak (PPE) flow.
  
  
  METHODS
  a tapered stent-graft (Gianturco stent + Dacron) was deployed with proximal and distal necks made of silicone. The amount of PPE was measured over 30-s periods while the angulation of the proximal neck was increased.
  
  
  RESULTS
  PPE flow increased significantly for angulations > or =30 degrees. The graft was lifted off the neck wall and gaps between the stent-graft and the neck created.
  
  
  CONCLUSIONS
  greater neck angulation increased PPE flow. The stent-graft was lifted off the neck and subsequent gaps created. This model could be used to compare available stent-grafts and to test new designs that would improve the seal in angulated necks.
authors.affiliation: Vascular Surgery Department, Queen's Medical Centre, Nottingham, UK.
authors.forename: J N
authors.initials: JN
authors.lastname: Albertini
authors.forename: J A
authors.initials: JA
authors.lastname: Macierewicz
authors.forename: S W
authors.initials: SW
authors.lastname: Yusuf
authors.forename: P W
authors.initials: PW
authors.lastname: Wenham
authors.forename: B R
authors.initials: BR
authors.lastname: Hopkinson
mesh_terms: D000714:Anastomosis, Surgical; D017544:Aortic Aneurysm, Abdominal / Q000601:surgery*; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects*; D006801:Humans; D008954:Models, Biological; D011474:Prosthesis Design; D012039:Regional Blood Flow; D015607:Stents