Vaso-occlusive devices with in-situ stiffening
View Patent ↗A vaso-occlusive device includes a first coil made from a first substantially non-expansile material, and a second coil at least partially co-wound with the first coil and made from a second expansile material. The second coil has a contracted state and an expanded state, in which the second coil expands radially and/or longitudinally. The vaso-occlusive device has increased stiffness when the second coil is in its expanded state.
1. A vaso-occlusive device, comprising:
a first coil made from a first material wherein the first coil forms first coil loops; and
a second coil forming second coil loops at least partially co-wound with the first coil loops and made from a second material, wherein the first material is substantially non-expansile and the second material is expansile.
2. The vaso-occlusive device of claim 1 , wherein the first material is a metal.
3. The vaso-occlusive device of claim 2 , wherein the first material is selected from the group consisting of platinum, platinum-tungsten alloy, platinum-iridium alloy, platinum rhenium alloy, and platinum palladium alloy.
4. The vaso-occlusive device of claim 1 , wherein the second material is a polymer.
5. The vaso-occlusive device of claim 4 , wherein the second material is a hydrogel.
6. The vaso-occlusive device of claim 1 , wherein the first coil loops and the second coil loops are packed together such that each loop is in contact with loops adjacent thereto.
7. The vaso-occlusive device of claim 1 , further comprising spaces disposed between at least some of the first coil loops and respective adjacent second coil loops.
8. The vaso-occlusive device of claim 1 , wherein the first and second coils are co-wound such that a plurality of successive first coil loops separate an adjacent pair of second coil loops.
9. The vaso-occlusive device of claim 1 , wherein the first and second coils are co-wound such that a plurality of successive second coil loops separate an adjacent pair of first coil loops.
10. The vaso-occlusive device of claim 1 , wherein the first and second coils are co-wound such that a plurality of successive first coil loops are adjacent a plurality of successive second coil loops.
11. The vaso-occlusive device of claim 1 , wherein the second coil has a contracted state and an expanded state.
12. The vaso-occlusive device of claim 11 , wherein the second coil expands radially in its expanded state.
13. The vaso-occlusive device of claim 11 , wherein the second coil and the vaso-occlusive device both expand longitudinally when the second coil is in its expanded state.
14. The vaso-occlusive device of claim 11 , wherein the second coil transitions from its contracted state to its expanded state when it absorbs liquid.
15. The vaso-occlusive device of claim 11 , wherein, when the second coil is in its expanded state, the second coil loops compress the first coil loops.
16. The vaso-occlusive device of claim 11 , the second coil defining an axial lumen, wherein, when the second coil is in its expanded state, the second coil loops substantially close the lumen.
17. The vaso-occlusive device of claim 11 , wherein the vaso-occlusive device has increased stiffness when the second coil is in its expanded state.
18. The vaso-occlusive device of claim 1 , further comprising third and fourth coils at least partially co-wound with the first and second coils.
19. The vaso-occlusive device of claim 1 , wherein the first coil loops and the second coil loops are collated together.
20. A vaso-occlusive device, comprising:
a first coil forming first coil loops and made from a first material; and
a second coil forming second coil loops and at least partially co-wound with the first coil loops and made from a second material coated with a third material, wherein the first and second materials are substantially non-expansile and the third material is expansile.