Fast-detaching electrically insulated implant

• US 6,425,914 B1
• Filed: 09/21/2000
• Issued: 07/30/2002
• Est. Priority Date: 08/29/1997
• Status: Expired

• Current Assignee: Stryker European Operations Holdings, LLC (Stryker Corporation)
• Original Assignee: Target Therapeutics, Inc. (Boston Scientific Corporation)
• Inventors: Bashiri, Mehran, Wallace, Michael P., Roue, Chad C.
• Primary Examiner(s): Nguyen, Dinh X.
• Assistant Examiner(s): Miller, Cheryl L.
• Application Number:
  US09/668,033
• Time in Patent Office: 677 Days
• Field of Search: 623/1.11, 623/11, 623/12, 606/200, 606/195, 606/198
• US Class Current: 623/1.11
• 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 17/1215 comprising additional materials, e.g. thrombogenic, having filaments, having fibers, being coated
• CPC Class Codes: A61B 17/12154 having stretch limiting means
• CPC Class Codes: A61B 2017/12063 electrolytically detachable
• CPC Class Codes: A61F 2/01 Filters implantable into blood vessels
• CPC Class Codes: A61F 2/0105 Open ended, i.e. legs gathered only at one side
• CPC Class Codes: A61F 2/011 Instruments for their placement or removal
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts

Abstract

This is an implant for placement in the human body and an assembly for so placing that implant. Most desirably, it is an implant for use in the vasculature of the human body and is used to occlude some space in that vasculature as a portion of a treatment regimen. The implant itself is preferably a component of a deployment device using an electrolytically severable joint. The implant component is at least partially covered with a highly resistive or insulative covering. The highly resistive or insulative layer or covering appears to enhance the susceptibility of the electrolytic joint to quick erosion and thus detachment of the implant. Although the implant itself is preferably a vaso-occlusive device, it may instead be a stent, a vena cava filter, or other implant which may be installed in this manner. The implant may be independently coated with insulative or resistive material or may be formed using a material with such as tantalum, which forms such an insulator or resistor in situ.

Claims

1. A method for introducing an implant member into a selected space within the human body comprising:

placing an implant member via an attached core wire into the selected space, said implant member having a proximal end and a distal end and having an implant member core at least partially covered with an inorganic insulative covering, and

detaching the implant from the core wire.

2. The method of claim 1 wherein the implant member further comprises an electrolytically severable joint attached to the implant member proximal end, the joint being relatively more susceptible to electrolysis in an ionic solution than is the implant member, and the step of detaching the implant from the core wire is accomplished electrolytically.

3. The method of claim 1 wherein the implant member at least partially comprises an oxide-forming material.

4. The method of claim 1 wherein the implant member comprises a core at least partially covered by a oxide-forming member.

5. The method of claim 2 wherein the implant member comprises a core at least partially covered by an oxide-forming material.

6. The method of claim 1 wherein the implant member comprises a stent.

7. The method of claim 1 wherein the implant member comprises a vena cava filter.

8. The method of claim 1 wherein the implant member comprises a helically wound coil.

9. The method of claim 8 wherein the coil further comprises a stretch resistant member extending at least partially from a proximal end of the coil to a distal end of the coil.

10. The method of claim 9 wherein the stretch resistant member comprises polypropylene.

11. The method member of claim 1 wherein the implant member comprises a braid.

12. A method for occluding a selected space within a human body comprising:

placing the tip of a catheter near the selected space,

introducing into a lumen of said catheter a tantalum occluding member having a proximal end and a distal end and further comprising an electrolytically severable joint attached to the occluding member proximal end, the joint being relatively more susceptible to electrolysis in an ionic solution than is the occluding member,

placing the occluding member into the space through the catheter tip, and

electrolytically severing the joint.

13. The method of claim 12 wherein the occluding member is at least partially covered with tantalum oxide.

14. The method of claim 12 wherein the occluding member comprises a coil.

15. The method of claim 14 wherein the coil further comprises a stretch resistant member extending at least partially from a proximal end of the coil to a distal end of a coil.

16. The method of claim 12 wherein the occluding member comprises a braid.

17. A method for occluding an aneurysm comprising:

placing the tip of a catheter near the aneurysm via a blood vessel,

introducing into a lumen of the catheter a vaso-occlusive coil having a proximal end and a distal end and a highly resistive or insulative layer on at least a portion of the coil, the coil further comprising a sacrificial link attached to the coil proximal end, the link being relatively more susceptible to electrolysis in an ionic solution than is the coil, said link connected to a core wire,

advancing the coil through the catheter lumen, out the catheter tip and into the aneurysm,

applying a positive electric current to the core wire to dissolve the link, and

removing the core wire and catheter from the vessel.

18. The method of claim 17 wherein the coil comprises tantalum.

19. The method of claim 18 wherein the coil is at least partially covered with tantalum oxide.

20. The method of claim 17 wherein the core wire comprises platinum.