IMPLANT, A MANDREL, AND A METHOD OF FORMING AN IMPLANT

• US 20080228216A1
• Filed: 02/27/2008
• Published: 09/18/2008
• Est. Priority Date: 03/13/2007
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Micro Therapeutics, Inc. (Medtronic Plc)
• Inventors: Hewitt, Todd Jeffrey, Divino, Vince, Vu, Khoa Dang, Brennan, Scott William, Patterson, William Robert, Strauss, Brian Michael, Carrillo, Ramon Torres, Wilbur, Larry, Klotz, Justin
• Granted Patent: US 8,801,747 B2
• Time in Patent Office: Days
• US Class Current: 606/191
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61B 17/12113 within an aneurysm
• CPC Class Codes: A61B 17/12145 having a pre-set deployed three-dimensional shape methods of manufacturing A61B2017/00526
• CPC Class Codes: A61B 17/12154 having stretch limiting means
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• CPC Class Codes: A61B 2017/00862 elastic or resilient
• CPC Class Codes: A61B 2017/00867 shape memory effect

Abstract

This invention is directed to an implant having a coil for embolizing a vascular site, such as aneurysm. The coil has a specific three-dimensional shape that is achieved by winding the coil around a mandrel in a specific pattern and then heat setting the coil and the mandrel, another aspect of the invention. The three-dimensional shape resembles unclosed mobius loops. Also provided are methods of making the coil and methods of embolizing vascular site.

Claims

1. A 3-dimensional vascular coil comprising one or more unclosed mobius loops.

8. The implant of claim 1 or 2, wherein the coil substantially conforms to a vascular site.

9. The implant of claim 1 or 2, wherein the coil is comprised of a metal wire.

10. The implant of claim 9, wherein the wire is comprised of a metal selected from the group consisting of platinum, palladium, rhodium, rhenium, iridium, gold, silver, tungsten, tantalum, an alloy of two or more of these metals, or a super elastic metal.

11. The implant of claim 10, wherein the wire is a platinum alloy.

12. A method of embolizing a vascular site of a patient comprising delivering an implant of claim 1 or 2 via a delivery device to the vascular site thereby embolizing the vascular site.

13. The method of claim 12, wherein the implant substantially conforms to the vascular site.

14. The method of claim 13 comprising delivering additional implants to the vascular site.

2. An implant comprising:

a coil having a coil length that is biased to conform to a winding pattern, the winding pattern approximately conforming to a shape of an outer surface of a sphere, the winding pattern having at least one unclosed mobius loops distributed over the shape.

3. The implant of claim 2, wherein the winding pattern has a plurality of unclosed mobius loops distributed over the shape.

4. The implant of claim 2, wherein the winding pattern further comprises

eight substantially triangularly-shaped sections distributed over the shape.

5. The implant of claim 4, wherein the triangular shapes have a center and four of the triangular shapes have sides that bow outwards away from the center.

6. The implant of claim 4, wherein the triangular shapes have a center and four of the triangular shapes have sides that bow inwards towards the center.

7. The implant of claim 2, wherein the winding pattern further comprises at least one loop having at least a first type of curve and a second type of curve, the first type of curve corresponding to a shape of a sphere and the second type of curve comprising a plurality of curves corresponding to eight substantially triangularly-shaped sections disposed along a path of at least one loop.

15. A mandrel comprising:

a sphere having four markers distributed on a surface of the sphere, each marker defined by a cylinder abutting the surface of the sphere; and

the surface of the sphere between the markers defining a winding pattern across the surface of the sphere, a plurality of midpoints on the surface of the sphere between adjacent markers defining a plurality of crossing points of the winding pattern.

16. The mandrel of claim 15 further comprising

a stem extending from one of the four markers.

17. The mandrel of claim 16, wherein the mandrel has a ratio of marker diameter to sphere diameter of between about 0.5 and about 0.75.

18. The mandrel of claim 17, wherein the ratio is about 0.55 to 0.7.

19. The mandrel of claim 18, wherein the ratio is between about 0.61 and about 0.65.

20. The mandrel of claim 15, wherein the markers comprise caps on a radial extreme of the marker.

21. The mandrel of claim 20, wherein the caps have an outer diameter that is greater than an outer diameter of the marker.

22. The mandrel of claim 15, wherein each of the markers defines an axis that passes through the center of the sphere.

23. The mandrel of claim 22, wherein the axis of the marker having the stem is at about 19.5 degrees angle compared to the other three axes.

24. The mandrel of claim 23, wherein the remaining three of the axes are at a horizontal angle of about 120 degrees with respect to each other.

25. A method for forming a coil with a mandrel, comprising:

winding the coil around a marker of the mandrel to form an initial wind;

winding the coil across the surface of the mandrel between each of four markers disposed on the surface of the mandrel providing at least one unclosed mobius loop, the winding including crossing the coil over itself at each of a plurality of midpoints disposed on the exterior surface of the mandrel midway between each of two adjacent markers.

26. The method of claim 25 further comprising

heating the mandrel and the coil wrapped around the mandrel.

27. The method of claim 26 further comprising

removing the coil from the mandrel.

28. The method of claim 25, wherein the coil is wound to provide a plurality of unclosed mobius loops.