title: The success of flow diversion in large and giant sidewall aneurysms may depend on the size of the defect in the parent artery.
abstract: OBJECTIVE
  Flow diverters are designed to occlude aneurysms while preserving flow to jailed arterial branches. We postulated that treatment success depended on the size of the aneurysm ostium or defect in the parent artery.
  
  
  METHODS
  Flow diverter expansion and deformation were studied in silicone tubes with wall apertures of various sizes. Large and giant canine sidewall aneurysms, featuring a branch located immediately opposite the aneurysm, and a smaller 6- to 8-mm (group A, n = 6) or a larger 10- to 16-mm (group B, n = 6) ostium were created to study the effects of ostium size on aneurysm or branch occlusion by flow diverters. Angiographic results after deployment and at 3 months were scored by using an ordinal scale. The amount of neointima formation on the segment of the device overlying the aneurysm or the branch ostia was determined by specimen photography.
  
  
  RESULTS
  The fusiform deformation of flow diverters was maximal with larger defects in silicone tubes. At 3 months, group B aneurysms showed worse angiographic results than group A aneurysms, with larger residual aneurysm volumes (P = .002). Neointimal coverage of the aneurysm ostia was more complete in group A compared with group B (P = .002).
  
  
  CONCLUSIONS
  The effects of flow diversion may vary with the size of the aneurysm ostium.
authors: From the Department of Radiology (J.C.G., J.R.), Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital, Montreal, Quebec, Canada Groupe d'étude de la Thrombose en Bretagne Occidentale (J.C.G.), Université de Bretagne Occidentale, Brest, France.
authors: J C
authors: JC
authors: Gentric
authors: Division of Neurosurgery (T.E.D.), Department of Surgery, University of Alberta Hospital, Mackenzie Health Sciences Centre, Edmonton, Alberta, Canada.
authors: T E
authors: TE
authors: Darsaut
authors: Laboratory of Interventional Neuroradiology (A.M., I.S., J.R.), Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital Research Centre, Montreal, Quebec, Canada.
authors: A
authors: A
authors: Makoyeva
authors: Laboratory of Interventional Neuroradiology (A.M., I.S., J.R.), Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital Research Centre, Montreal, Quebec, Canada.
authors: I
authors: I
authors: Salazkin
authors: From the Department of Radiology (J.C.G., J.R.), Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital, Montreal, Quebec, Canada Laboratory of Interventional Neuroradiology (A.M., I.S., J.R.), Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital Research Centre, Montreal, Quebec, Canada. jean.raymond@umontreal.ca.
authors: J
authors: J
authors: Raymond
mesh_terms: D000783:Aneurysm / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D000792:Angiography; D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D015607:Stents; D014656:Vascular Surgical Procedures / Q000295:instrumentation* / Q000379:methods*