Filamentary devices for treatment of vascular defects

A method for treating a cerebral aneurysm, comprising the steps of:

• providing an implant comprising a single layer of woven braided mesh, the implant having a proximal end with a hub, a distal end, and a longitudinal axis extending from the proximal end to the distal end, and a length,
• wherein the implant has a distal region having a plurality of pore having an average diameter, a proximal region having a plurality of pore having an average diameter, and a transition region that lies substantially perpendicular to the longitudinal axis of the implant and extends between the distal and proximal regions and has a length;
• wherein the implant has an expanded globular configuration when deployed, the expanded implant having a region of maximum diameter that extends from a proximal portion of the distal region through the transition region and to a distal portion of the proximal region,
• wherein the average diameter of the plurality of pores in the distal region is greater than the average diameter of the plurality of pores in the proximal region, and wherein the length of the transition zone may be about 0.5% to about 20% of the length of the implant;
• advancing the implant in the low profile radially constrained state within a microcatheter to a region of interest within a cerebral artery;
• deploying the implant within the cerebral aneurysm, wherein the distal and proximal permeable shells expand to their expanded shapes;
• and
• withdrawing the microcatheter from the region of interest after deploying the implant.