Medical Implant

• US 20080319532A1
• Filed: 09/22/2004
• Published: 12/25/2008
• Est. Priority Date: 09/22/2004
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: ev3, Inc. (Medtronic Plc)
• Inventors: Hannes, Ralf, Monstadt, Hermann, Henkes, Hans, Flesser, Achim
• Granted Patent: US 7,879,064 B2
• Time in Patent Office: Days
• US Class Current: 623/1.22
• 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 2017/00526 Methods of manufacturing
• CPC Class Codes: A61B 2017/00867 shape memory effect for prostheses A61F2210/0014
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

The invention relates to a medical implant (1′) in the form of an elongated helix wherein at least one part of the helix is preformed in such a manner that it has a secondary structure of identically sized loops which it assumes during implantation at the placement site, with said structure in turn forming at the placement site during implantation a polyhedral tertiary structure, and the polyhedron being provided with at least one additional loop.

Claims

1. A medical implant comprising:

an elongated helix;

at least one part of the helix preformed to define a secondary structure with loops of substantially identical size during implantation at a placement site;

said secondary structure forming at the placement site a polyhedral tertiary structure with each face of the polyhedron being built up by a loop, and

the polyhedron provided with at least one additional loop.

2. Medical implant according to claim 1, characterized in that the additional loop is arranged in an area selected from a polyhedron face, polyhedron edge, and a polyhedron vertex.

3. Medical implant according to claim 1 characterized in that the polyhedron is selected from a tetrahedron, a hexahedron, an octahedron, a dodecahedron, a pentagonal dodecahedron, and an icosahedron.

4. Medical implant according to claim 1, characterized in that the loops are closed loops.

5. Medical implant according to claim 1, characterized in that the at least one additional loop is smaller than the loops forming the polyhedron faces.

6. The medical implant according to claim 5, characterized in that the numerical proportion between smaller and greater loops is approximately 1:

1.

7. The medical implant according to claim 4, characterized in that the closed loops are alternately arranged in a linear extension of the elongated helix.

8. Medical implant according to claim 7, further comprising characterized in that in the polyhedron a smaller loop arranged in each of the polyhedron faces which are formed by the large loops.

9. Medical implant according to claim 7, characterized in that in the polyhedron a small loop is arranged between two adjacent large loops.

10. Medical implant according to claim 7, characterized in that in the polyhedron a small loop is arranged between three adjacent large loops.

11. Medical implant according to claim 1, characterized in that the size of the polyhedron is greater than the volume of the body cavity which it is meant to fill.

12. Medical implant according to claim 1, characterized in that the elongated helix in extended state has a length ranging between 50 and 600 mm.

13. Medical implant according to claim 1, characterized by a microcoil having a lumen which is closed at least at a distal end thereof.

14. Medical implant according to claim 1, characterized in that the elongated helix has an outside diameter ranging between 0.1 and 0.5 mm.

15. Medical implant according to claim 1, characterized in that at least one of the wires forming the elongated helix comprises one of a platinum-iridium and platinum-tungsten alloy having shape memory properties.

16. Medical implant according to claim 1, characterized in that a filamentous shaping element made of a metal alloy having shape memory properties passes through the elongated helix along a longitudinal axis thereof.

17. Medical implant according to claim 16, characterized in that a filamentous retaining element (16) made of a polymer material or a metal wire without shape memory properties passes elongated helix along a longitudinal axis thereof.

18. The medical implant according to claim 16, characterized in that the diameter of the filamentous shaping element (16) reduces towards a distal end thereof.

19. Medical implant according to claim 18, characterized in that the diameter of the filamentous shaping element (16) at the distal end amounts to 25 to 50% of a remaining diameter of the shaping element.

20. The medical implant according to claim 18, characterized in that the diameter of the filamentous shaping element constantly narrows in the range of the distal end.

21. Medical implant according to claim 1 further comprising at least one severance module provided with an electrolytically corrodible location which is arranged in the elongated helix proximally to a portion thereof forming the polyhedron.

22. A medical implant according to claim 1 in combination with an insertion aid which is detachably connected to the proximal end (11) of the implant.

23. The combination according to claim 22 comprising a catheter, a voltage source and a cathode, with the medical implant serving as an anode and being longitudinally movable in the catheter, with the connection between the medical implant and the insertion aid having an electrolytically corrodible location so that the medical implant can be detached by an electrolytic processes when in contact with a body fluid.

24. The combination according to claim 23, characterized in that the insertion aid has the form of a guide wire.

25. The combination according to claim 24, characterized in that the guide wire has, at least in part, the form of one of a helix and a spring.

26. The combination according to claim 25, characterized in that the medical implant and the insertion aid are connected with each other by means of a severance module provided with an electrolytically corrodible location.

27. The combination according to claim 26, characterized in that the severance module is provided with a proximal and a distal helix as well as a segment arranged in between, with the helixes consisting of a material whose susceptibility to electrolytic corrosion is lower than that of the interposed segment.

28. The combination according to claim 27, characterized in that the severance module is non-detachably connected to the medical implant and the insertion aid by a process selected from welding, soldering, bonding, mechanical force closing and mechanical form-closing.

29. The combination according to claim 23, characterized in that the insertion aid is at least partially surrounded, by one of an electrically insulating shrunk-on sleeve and an electrically insulating coating.