Vaso-occlusive devices including a friction element
Vaso-occlusive apparatuses, including implants, and methods of using them to treat aneurysms. The vaso-occlusive implants described herein include one or more soft and expandable braided member coupled to a pushable member such as a coil that maybe inserted and retrieved from within an aneurism using a delivery catheter as well as a friction element between the soft braided member and the coil. The friction element allows the relatively soft and elongate implant to be pushed out of a cannula without binding up within the cannula.
1. A vaso-occlusive device adapted to be pushed through a delivery catheter and out an open distal end of the delivery catheter, the vaso-occlusive device comprising:
an elongate braided tubular outer member having a radially compressed configuration when constrained within the delivery catheter, and a radially expanded configuration when pushed out the distal end of the delivery catheter so as to no longer be constrained within the delivery catheter;
an elongate pushable inner member disposed within an interior of the braided tubular outer member, wherein the pushable inner member is axially moveable relative to the delivery catheter; and
a friction element disposed between the pushable inner member and the braided tubular outer member, wherein at least a portion of the friction element is expandable to engage an inner surface of the braided tubular outer member when the vaso-occlusive device is constrained within the delivery catheter so as to move the braided tubular outer member axially relative to the delivery catheter as the pushable inner member is moved axially relative to the delivery catheter, wherein the friction element does not engage the braided tubular outer member when the braided tubular outer member is in the radially expanded configuration.
2. The vaso-occlusive device of claim 1 , wherein the friction element is coupled to the pushable inner member.
3. The vaso-occlusive device of claim 2 , wherein a proximal end of the friction element is coupled to the pushable inner member, and a distal end of the friction element comprises prongs that extend radially outward to engage the braided tubular outer member.
4. The vaso-occlusive device of claim 3 , wherein the prongs extend through open cells of the braided tubular outer member when the braided tubular outer member is in the radially compressed configuration.
5. The vaso-occlusive device of claim 2 , wherein the friction element comprises a braided bump having a distal end and a proximal end, wherein the distal and proximal ends of the braided bump are each coupled to the pushable inner member.
6. The vaso-occlusive device of claim 5 , wherein the proximal end of the braided bump is axially and radially fixed relative to the pushable inner member, and wherein the distal end of the braided bump is axially slidable relative to the pushable inner member.
7. The vaso-occlusive device of claim 6 , wherein a middle portion of the braided bump radially expands when the distal end of the braided bump slides axially towards the proximal end of the braided bump.
8. The vaso-occlusive device of claim 1 , wherein the friction element comprises a braided structure.
9. The vaso-occlusive device of claim 1 , wherein the friction element is a free-floating friction element that is not attached to the pushable inner member or to the braided tubular outer member.
10. The vaso-occlusive device of claim 9 , wherein the free-floating friction element comprises a braided structure having flared ends that protrude into open cells of the braided tubular outer member when the braided tubular outer member is in the radially compressed configuration.
11. A vaso-occlusion system, comprising:
a delivery catheter extending from a proximal end to an open distal end; and
a vaso-occlusive device disposed within the delivery catheter, wherein the vaso-occlusive device is adapted to be pushed out the open distal end of the delivery catheter, the vaso-occlusive device comprising
an elongate braided tubular outer member having a radially compressed configuration when constrained within the delivery catheter, and a radially expanded configuration when pushed out the distal end of the delivery catheter so as to no longer be constrained within the delivery catheter,
an elongate pushable inner member disposed within an interior of the braided tubular outer member, wherein the pushable inner member is axially moveable relative to the delivery catheter, and
a plurality of friction elements disposed between the pushable inner member and the braided tubular outer member, wherein at least a portion of each of the friction elements is expandable to engage an inner surface of the braided tubular outer member when the vaso-occlusive device is constrained within the delivery catheter so as to move the braided tubular outer member axially relative to the delivery catheter as the pushable inner member is moved axially relative to the delivery catheter,
wherein the friction elements do not engage the pushable inner member when the vaso-occlusive device is in the radially expanded configuration.
12. The vaso-occlusion system of claim 11 , wherein each of the friction elements is coupled to the pushable inner member.
13. The vaso-occlusion system of claim 12 , wherein a proximal end of each friction element is coupled to the pushable inner member, and a distal end of each friction element comprises prongs that extend radially outward to engage the braided tubular outer member.
14. The vaso-occlusion system of claim 13 , wherein the respective prongs of each friction element extend through open cells of the braided tubular outer member when the braided tubular outer member is in the radially compressed configuration.
15. The vaso-occlusive system of claim 12 , wherein each friction element comprises a braided bump having a distal end and a proximal end, wherein the distal and proximal ends of the respective braided bumps are coupled to the pushable inner member.
16. The vaso-occlusive system of claim 15 , wherein the proximal end of each braided bump is axially and radially fixed relative to the pushable inner member, and wherein the distal end of each braided bump is axially slidable relative to the pushable inner member.
17. The vaso-occlusive system of claim 16 , wherein a middle portion of each braided bump radially expands when the distal end of respective the braided bump slides axially towards the proximal end of the respective braided bump.
18. The vaso-occlusive system of claim 11 , wherein the friction elements comprise braided structures.
19. The vaso-occlusive system of claim 11 , wherein the friction elements comprise free-floating friction elements that are not attached to the pushable inner member or to the braided tubular outer member.
20. The vaso-occlusive system of claim 19 , wherein each of the free-floating friction elements comprises a braided structure having flared ends that protrude into open cells of the braided tubular outer member when the braided tubular outer member is in the radially compressed configuration.