Apparatus for delivery of pharmaceuticals to the cochlea

• US 20040078057A1
• Filed: 11/10/2003
• Published: 04/22/2004
• Est. Priority Date: 11/14/2000
• Status: Active Grant

• Current Assignee: Cochlear Limited
• Original Assignee: Cochlear Limited
• Inventors: Gibson, Peter
• Granted Patent: US 7,571,012 B2
• Time in Patent Office: Days
• US Class Current: 607/3
• CPC Class Codes: A61M 2205/054 with electrotherapy
• CPC Class Codes: A61M 2210/0662 Ears
• CPC Class Codes: A61M 2210/0668 Middle ear
• CPC Class Codes: A61M 2210/0675 Eustachian tube
• CPC Class Codes: A61M 25/00 Catheters; Hollow probes dilators A61M29/00; peritoneal catheters A61M1/285; tracheal tubes A61M16/04; for drainage A61M27/00; for uterus, vagina or rectum A61M31/00 ; for measuring or testing A61B; materials for catheters A61L29/00
• CPC Class Codes: A61M 31/00 Devices for introducing or retaining media, e.g. remedies, in cavities of the body A61M25/00 takes precedence ; introducing or retaining ophthalmic products into the ocular cavities A61F9/0008
• CPC Class Codes: A61M 31/002 Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50
• CPC Class Codes: A61N 1/0541 Cochlear electrodes
• CPC Class Codes: A61N 1/32 alternating or intermittent currents applying electric fields by inductive or capacitive coupling A61N1/40; microwave apparatus A61N5/02
• CPC Class Codes: A61N 1/36038 Cochlear stimulation
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/49885 with coating before or during assembling

Abstract

An implantable tissue-stimulating device, such as a cochlear implant, having a resiliently flexible elongate member (11) having a plurality of electrodes (12) positioned thereon. The elongate member (11) provides a means of delivering at least one bio-active substance to the implantee following implantation of the elongate member (11). The delivery means can comprise a lumen 21 containing the bio-active substance in a liquid form. The bio-active substance can comprise a steroid or can perform a function of reducing the resting neuron potential of neurons within the cochlea.

Claims

1. An implantable tissue-stimulating device comprising:

a resiliently flexible elongate member having a plurality of electrodes mounted thereon; and

a bio-active substance delivery means adapted to deliver at least one bio-active substance to the implantee following implantation of the device.

2. A device of claim 1 wherein the device is a cochlear implant electrode assembly.

3. A device of claim 2 wherein the substance delivery means comprises at least a portion of the elongate member impregnated with a bio-active substance that can leach therefrom following implantation.

4. A device of claim 2 wherein the elongate member has a first end that is firstly inserted into the implantee.

5. A device of claim 4 wherein the substance delivery means comprises a lumen extending through the elongate member for at least a portion of the length of the elongate member.

6. A device of claim 5 wherein the lumen extends through the elongate member from an opening distal the first end to a position that is at or adjacent the first end.

7. A device of claim 6 wherein the distal opening of the lumen is closable by a closure means adapted to seal the opening of the lumen.

8. A device of claim 7 wherein the closure means comprises a plug insertable in the lumen to form a seal therewith.

9. A device of claim 8 wherein the plug is formed from a resiliently flexible material selected from the group comprising a silicone and a polyurethane.

10. A device of claim 6 wherein the lumen in the elongate member acts as a reservoir for a bio-active substance within the elongate member.

11. A device of claim 10 wherein the elongate member has at least one substance egress means whereby the bio-active substance leaves the lumen and the elongate member to a position of implantation of the elongate member.

12. A device of claim 11 wherein the bio-active substance is carried in or comprises a fluid and said at least one substance egress means is a fluid egress means.

13. A device of claim 12 wherein each said at least one fluid egress means has a valve means that allows fluid to exit the lumen but at least substantially prevents fluid flow from external the elongate member back into the lumen within the elongate member.

14. A device of claim 10 wherein the distal opening of the lumen is in fluid communication with an additional reservoir for the bio-active substance that is external to the elongate member.

15. A device of claim 14 wherein a pumping means transfers the bio-active substance from the additional reservoir into the lumen of the elongate member for subsequent delivery to the site of implantation of the elongate member.

16. A device of claim 10 wherein the bio-active substance is impregnated in a ceramic or a polymer pellet having a predetermined rate of release of the bioactive substance stored in the lumen of the elongate member.

17. A device of claim 2 wherein the bioactive substance comprises a steroid.

18. A device of claim 2 wherein the bioactive substance performs a function of reducing the resting neuron potential of neurons within the cochlea.

19. A device of claim 6 wherein the elongate member has a first configuration that allows said member to be inserted into an implantee'"'"'s cochlea, and a second configuration wherein said elongate member is adapted to apply a preselected tissue stimulation with the electrodes.

20. A device of claim 19 wherein the elongate member has at least one intermediate configuration between said first and second configurations.

21. A device of claim 2 wherein at least a portion of the outer surface has a coating of lubricious material.

22. A device of claim 21 wherein the lubricious material is selected from the group comprising polyacrylic acid (PAA), polyvinyl alcohol (PVA), polylactic acid (PLA) and polyglycolic acid (PGA).

23. A device of claim 21 wherein the lubricious material is impregnated with a bio-active substance.

24. A device of claim 19 wherein the device further comprises a stiffening element extending through the elongate member and made of a second material relatively stiffer than the resiliently flexible material of the elongate member and adapted to bias the elongate member into the first configuration.

25. A device of claim 19 wherein the device further comprises a stiffening sheath that at least partially envelops said elongate member and made of a material that is relatively stiffer than the resiliently flexible material of the elongate member, the stiffening sheath adapted to bias the elongate member into the first configuration.

26. A device of claim 25 wherein the stiffening sheath is at least partially overlaid by a coating of a lubricious material.

27. A device of claim 19 wherein the second configuration of the elongate member is curved.

28. A device of claim 27 wherein the elongate member adopts a spiral configuration when in the second configuration.

29. A device of claim 19 wherein the first configuration is at least substantially straight.

30. A device of claim 2 wherein the elongate member is formed from a biocompatible material selected from the group comprising a silicone and a polyurethane.

31. A device of claim 24 wherein the stiffening element is formed of a bioresorbable material which softens or dissolves on exposure to cochlear fluid.

32. A device of claim 31 wherein the bioresorbable material of the stiffening element is selected from the group comprising polyacrylic acid (PAA), polyvinyl alcohol (PVA), polylactic acid (PLA) and polyglycolic acid (PGA).

33. A device of claim 32 wherein the bioresorbable material of the stiffening element is impregnated with one or more bio-active substances.

34. A device of claim 24 wherein the stiffening element is formed from a non-bioresorbable material selected from the group comprising a metallic stylet and a non-metallic stylet.

35. A device of claim 2 wherein the device is adapted to deliver the bio-active substance to the implantation site of the elongate member for a predetermined period of time following implantation.

36. An implantable tissue-stimulating device comprising:

a resiliently flexible elongate member having a plurality of electrodes mounted thereon, the elongate member surrounding a sealable reservoir for storing within the member at least one bio-active substance for delivery to an implantee following implantation of the device.

37. A cochlear implant electrode assembly comprising:

a resiliently flexible elongate member having a plurality of electrodes mounted thereon, the elongate member surrounding a sealable reservoir for storing within the member at least one bio-active substance for delivery to a cochlea of an implantee following implantation of the device.

38. A cochlear implant electrode assembly of claim 37 wherein the reservoir comprises a sealable lumen extending through the elongate member for at least a portion of the length of the elongate member.

39. A cochlear implant electrode assembly of claim 38 wherein the elongate member has at least one substance egress means whereby the bio-active substance leaves the lumen and the elongate member to a position of implantation of the elongate member.

40. A cochlear implant electrode assembly of claim 39 wherein the bio-active substance is carried in or comprises a fluid and said at least one substance egress means is a fluid egress means.

41. A cochlear implant electrode assembly of claim 40 wherein each said at least one fluid egress means has a valve means that allows fluid to exit the lumen but at least substantially prevents fluid flow from external the elongate member back into the lumen within the elongate member.

42. A cochlear implant electrode assembly of claim 37 wherein at least a portion of the elongate member is coated with a bioresorbable layer that seals the reservoir of the assembly prior to implantation.