Modification of hemodynamics in basilar artery aneurysm by the single and Y stent placement1

BACKGROUND: Stent placement can change the hemodynamics in basilar artery aneurysms. However, the effects of the stent placement can depend on the angle of vessel bifurcation. OBJECTIVE: The hemodynamics in and near the aneurysm are investigated for two angles of vessel bifurcation and two stent m odels. Some statistical indexes are calculated to evaluate the effects of the stent placements on the possibility of aneurysm rupture. METHODS: Computational fluid dynamics simulations and phantom model experiments are performed. The angle between the basilar and posterior cerebral arteries is set to 90 and 135 degrees. The single stent and Y stent models are tested in addition to the case without stent placement. RESULTS: The velocity in the aneurysm in the Y stent case is smaller than that in the no stent and single stent cases when the angle is 135 degrees. High OSI and low AFI areas often appear at the same locations, and the area is larger in the single stent case than in the no stent and Y stent cases. CONCLUSIONS: The Y stent placement promotes hemostasis and thrombosis in the basilar artery aneurysm, whereas the single stent placement can enhance the growth and rupture.