title: The study of flow diversion effects on aneurysm using multiple enterprise stents and two flow diverters.
abstract: BACKGROUND
  Computer-based simulation is necessary to clarify the hemodynamics in brain aneurysm. Specifically for endovascular treatments, the effects of indwelling intravascular devices on blood stream need to be considered. The most recent technology used for cerebral aneurysm treatment is related to the use of flow diverters to reduce the amount of flow entering the aneurysm. To verify the differences of flow reduction, we analyzed multiple Enterprise stents and two kinds of flow diverters.
  
  
  METHODS
  In this research, we virtually modeled three kinds of commercial intracranial stents (Enterprise, Silk, and Pipeline) and mounted to fit into the vessel wall, and deployed across the neck of an IC-ophthalmic artery aneurysm. Also, we compared the differences among multiple Enterprise stents and two flow diverters in a standalone mode.
  
  
  RESULTS
  From the numerical results, the values of wall shear stress and pressure are reduced in proportion to the size of mesh, especially in the inflow area. However, the reduced velocity within the aneurysm sac by the multiple stents is not as significant as the flow diverters.
  
  
  CONCLUSIONS
  This is the first study analyzing the flow alterations among multiple Enterprise stents and flow diverters. The placement of small meshed stents dramatically reduced the aneurysmal fluid movement. However, compared to the flow diverters, we did not observe the reduction of flow velocity within the aneurysm by the multiple stents.
authors.affiliation: Department of Micro-Nano System Engineering, Nagoya University, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kojima
authors.forename: Keiko
authors.initials: K
authors.lastname: Irie
authors.forename: Toshio
authors.initials: T
authors.lastname: Fukuda
authors.forename: Fumihito
authors.initials: F
authors.lastname: Arai
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Hirose
authors.forename: Makoto
authors.initials: M
authors.lastname: Negoro
keywords: Aneurysm; computational fluid dynamics; flow diverter; multiple stents
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