Filamentary devices for treatment of vascular defects
Devices and methods for treatment of a patient's vasculature are described. The device includes a self-expanding resilient permeable shell having a radially constrained state and an expanded state with a globular, axially shortened configuration. The permeable shell may be a single layer of braided elongate filaments having first and second ends that are secured at the proximal end of the permeable shell. The devices may also include permeable shells made of woven braided mesh having a variable mesh density, i.e., the average size of pores in one region are a different than the average size of pores in another region. Methods of using the device to treat a cerebral aneurysm are also described. Methods of forming a tubular braid are also described. Methods of forming a tubular braid with variable braid densities are described. Methods of forming a tubular braid using a castellated mandrel are also described.
1. A device for treatment of an aneurysm within a patient's vasculature, comprising:
a self-expanding resilient permeable shell having a proximal end, a distal end, and a longitudinal axis, the shell comprising a plurality of elongate resilient filaments having a braided structure, wherein each of the plurality of filaments has a first end and a second end, and wherein the first and second ends of each of the plurality of filaments are secured at the proximal end of the permeable shell, wherein the plurality of filaments comprise at least three different types of filaments, wherein at least some of the filaments of the plurality of filaments are drawn filled tubes, wherein the at least three different types of filaments are incorporated into a single braided mesh,
wherein the permeable shell has a radially constrained elongated state configured for delivery within a microcatheter, and
wherein the permeable shell has an expanded state having a substantially spherical shape, the expanded state having a length and an axially shortened configuration relative to the radially constrained state.
2. The device of claim 1 , wherein each of the plurality of filaments has a transverse dimension, and wherein the three different types of filaments comprise filaments having a first transverse dimension, filaments having a second transverse dimension, and filaments having a third transverse dimension.
3. The device of claim 2 , wherein the first, second, and third transverse dimensions are not equal.
4. The device of claim 2 , wherein the first transverse dimension is less than the second transverse dimension, and wherein the second transverse dimension is less than the third transverse dimension.
5. The device of claim 2 , wherein the first transverse dimension is between about 0.0005 inches to 0.001 inches.
6. The device of claim 2 , wherein the second transverse dimension is between about 0.00075 inches and 0.00125 inches.
7. The device of claim 2 , wherein the third transverse dimension is between about 0.001 inches to 0.002 inches.
8. The device of claim 1 , wherein each of the three different types of filaments comprise filaments of different materials.
9. The device of claim 1 , wherein at least some of the filaments of the plurality of filaments comprise platinum.
10. The device of claim 1 , wherein at least a portion of the permeable shell is coated with a growth factor.
11. The device of claim 1 , wherein at least some of the filaments of the plurality of filaments comprise bioresorbable filaments.
12. The device of claim 1 , further comprising an opening at the proximal end.
13. The device of claim 1 , wherein the permeable shell has a distal region having a plurality of pores having an average diameter, a proximal region having a plurality of pores having an average diameter, and a transition region that lies substantially perpendicular to the longitudinal axis of the permeable shell and extends between the distal and proximal regions and has a length.
14. The device of claim 13 , wherein the average diameter of the plurality of pores in the distal region is greater than 250 μm, and wherein the average diameter of the plurality of pores in the proximal region is 200 μm or less.
15. The device of claim 1 , wherein the filaments of the plurality of filaments are not secured together at the distal end of the permeable shell.