title: Cerebral aneurysms treated with flow-diverting stents: computational models with intravascular blood flow measurements.
abstract: OBJECTIVE
  Computational fluid dynamics modeling is useful in the study of the hemodynamic environment of cerebral aneurysms, but patient-specific measurements of boundary conditions, such as blood flow velocity and pressure, have not been previously applied to the study of flow-diverting stents. We integrated patient-specific intravascular blood flow velocity and pressure measurements into computational models of aneurysms before and after treatment with flow-diverting stents to determine stent effects on aneurysm hemodynamics.
  
  
  METHODS
  Blood flow velocity and pressure were measured in peri-aneurysmal locations by use of an intravascular dual-sensor pressure and Doppler velocity guidewire before and after flow-diverting stent treatment of 4 unruptured cerebral aneurysms. These measurements defined inflow and outflow boundary conditions for computational models. Intra-aneurysmal flow rates, wall shear stress, and wall shear stress gradient were calculated.
  
  
  RESULTS
  Measurements of inflow velocity and outflow pressure were successful in all 4 patients. Computational models incorporating these measurements demonstrated significant reductions in intra-aneurysmal wall shear stress and wall shear stress gradient and a trend in reduced intra-aneurysmal blood flow.
  
  
  CONCLUSIONS
  Integration of intravascular dual-sensor guidewire measurements of blood flow velocity and blood pressure provided patient-specific computational models of cerebral aneurysms. Aneurysm treatment with flow-diverting stents reduces blood flow and hemodynamic shear stress in the aneurysm dome.
authors.affiliation: Departments of Neurological Surgery.
authors.forename: M R
authors.initials: MR
authors.lastname: Levitt
authors.forename: P M
authors.initials: PM
authors.lastname: McGah
authors.forename: A
authors.initials: A
authors.lastname: Aliseda
authors.forename: P D
authors.initials: PD
authors.lastname: Mourad
authors.forename: J D
authors.initials: JD
authors.lastname: Nerva
authors.forename: S S
authors.initials: SS
authors.lastname: Vaidya
authors.forename: R P
authors.initials: RP
authors.lastname: Morton
authors.forename: B V
authors.initials: BV
authors.lastname: Ghodke
authors.forename: L J
authors.initials: LJ
authors.lastname: Kim
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D001794:Blood Pressure; D001807:Blood Vessel Prosthesis; D002536:Cerebral Arteries / Q000503:physiopathology* / Q000601:surgery; D002560:Cerebrovascular Circulation; D003198:Computer Simulation; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D008297:Male; D008955:Models, Cardiovascular; D008959:Models, Neurological; D011475:Prosthesis Failure; D013223:Statistics as Topic; D015607:Stents; D016896:Treatment Outcome