Methods and devices for treatment of vascular defects
Methods of implanting a device in the lumen of a blood vessel are described. The method includes providing a microcatheter and a device. The device includes a first hub, a second hub, a support structure including a plurality of struts disposed between the first hub and the second hub, and a layer of material disposed over the plurality of struts. The support structure has a low profile, radially constrained state with an elongated tubular configuration suitable for delivery from a microcatheter. The support structure also has an expanded state, a smooth outer surface, and has an axially shortened configuration relative to the radially constrained state. The microcatheter is advanced to a region of interest within the blood vessel. The support structure is advanced through the lumen of and out the distal end of the microcatheter where it expands to the expanded state.
1. A method of occluding a lumen of a tubular blood vessel, comprising the steps of:
advancing a distal end of a microcatheter to a region of interest within the tubular blood vessel;
advancing a device through a lumen of the microcatheter and out of the distal end of the microcatheter by advancing a pusher member such that the device deploys within the lumen of the tubular blood vessel, wherein the device comprises a first hub, a second hub, a support structure having a longitudinal axis, the support structure disposed between the first hub and the second hub, the support structure including a plurality of struts, and a layer of material disposed over the plurality of struts, wherein the first hub is cylindrical and connected to an end of each of the struts of the plurality of struts, wherein the pusher member is detachably coupled to the first hub via a detachment mechanism located within a lumen of the first hub, wherein the support structure has a radially constrained state with an elongated tubular configuration having a transverse dimension, the radially constrained state having a low profile suitable for delivery from the microcatheter, and wherein the support structure expands to an expanded state within the lumen of the tubular blood vessel, the expanded state having a tubular configuration having a first end, a second end, a total length, a longitudinal axis, a smooth outer surface and having an axially shortened configuration relative to the radially constrained state, wherein a first portion of the plurality of struts are in a zig-zag pattern and a second portion of the plurality of struts are straight in the expanded state, and wherein the layer of material spans the expanded state of the support structure from the first hub to a longitudinal position less than the total length of the expanded state; and
detaching the first hub from the pusher member,
wherein the longitudinal axis of the expanded state is substantially parallel to a longitudinal axis of the tubular vessel, and wherein the expanded support structure blocks a flow of fluid through the tubular vessel.
2. The method of claim 1 , wherein the layer of material comprises at least one of acrylic, silk, silicone, polyvinyl alcohol, polypropylene, polyester, PolyEtherEther Ketone (PEEK), polytetrafluoroethylene (PTFE), polycarbonate urethane (PCU) and polyurethane (PU).
3. The method of claim 1 , wherein the layer of material comprises polytetrafluoroethylene (PTFE).
4. The method of claim 1 , wherein the support structure is formed from a slotted tubular member.
5. The method of claim 1 , wherein the support structure comprises between about 4 struts and about 20 struts.
6. The method of claim 1 , wherein the support structure comprises between about 6 struts and about 12 struts.
7. The method of claim 1 , wherein the support structure comprises 8 struts.
8. The method of claim 1 , wherein 8 struts extend from at least one of the first hub and the second hub.
9. The method of claim 1 , wherein the plurality of struts of the support structure in its radially constrained state comprises a circumferential array of struts numbered between about 4 and about 20.
10. The method of claim 1 , wherein the plurality of struts of the support structure in its radially constrained state comprises a circumferential array of struts numbered between about 6 and about 12.
11. The method of claim 1 , wherein the plurality of struts of the support structure in its radially constrained state comprises a circumferential array of 8 struts.
12. The method of claim 1 , wherein at least one of the first or second ends is inverted.
13. The method of claim 1 , wherein the plurality of struts includes struts having a transverse cross section including a major transverse dimension disposed circumferentially with respect to the longitudinal axis of the support structure and a minor transverse dimension disposed radially with respect to the longitudinal axis of the support structure.
14. The method of claim 1 , wherein the support structure has a three dimensional contour, and wherein the layer of material has a three dimensional configuration that substantially matches at least a portion of the three dimensional contour of the support structure.
15. The method of claim 1 , wherein the layer of material is secured to the support structure at least in part by an adhesive.
16. The method of claim 1 , wherein the layer of material includes pores.
17. The method of claim 1 , wherein the expanded state of the support structure is a heat-formed three-dimensional shape.
18. The method of claim 1 , wherein the layer of material is stretched between adjacent struts of the plurality of struts when the support structure is in the expanded state.
19. The method of claim 1 , wherein each strut of the plurality of struts extends from the first hub to the second hub.
20. The method of claim 1 , wherein the expanded support structure does not block a flow of fluid through a saccular cavity.
21. The method of claim 20 , wherein the saccular cavity is an aneurysm.
22. The method of claim 1 , wherein the detachment mechanism is selected from a group consisting of a mechanical detachment mechanism, a thermal detachment mechanism and a electrolytic detachment mechanism.
23. The method of claim 1 , wherein a distal end of the device has a substantially closed configuration.
24. The method of claim 1 , wherein the second portion of the plurality of struts has a tapered configuration.