A flow diversion device for the treatment of intracranial aneurysms and other medical conditions is disclosed. The flow diversion device may include a generally tubular wire stent frame formed from a plurality of zig-zag shaped wire elements that are coupled together. The device further includes a base layer of graft material coupled to the wire stent frame and surrounding at least a portion thereof, the wire stent frame maintaining the base layer in an open condition. In some embodiments, the base layer may be formed of porous graft material having a plurality of slits formed in the longitudinal direction. The slits may have a different shape in a compressed configuration and an expanded configuration. The slits provide a passageway for a small blood flow to maintain the long-term patency of important small side branches, while also reducing blood flow to the aneurysm to promote occlusion and avoid potential rupture.
