Electrode assembly for nerve control

• US 20060195170A1
• Filed: 02/02/2006
• Published: 08/31/2006
• Est. Priority Date: 05/23/2002
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: BioControl Medical (B.C.M) Ltd.
• Inventors: Cohen, Ehud, Ben-David, Tamir, Ayal, Shai, Ben-Ezra, Omry
• Granted Patent: US 7,844,346 B2
• Time in Patent Office: Days
• US Class Current: 607/118
• CPC Class Codes: A61N 1/0556 Cuff electrodes

Abstract

Apparatus is provided for applying current to a nerve, including a housing, that is adapted to be placed in a vicinity of the nerve. At least one electrode is fixed to the housing such that the at least one electrode does not come in direct physical contact with the nerve, and such that the electrode surrounds greater than 180 degrees of a circumference of the nerve after the placement of the housing. Two end insulating elements are fixed to the housing. The at least one electrode is between the end insulating elements. A characteristic closest end insulating element distance to a surface of the nerve is less than 0.5 mm.

Claims

1. Apparatus for applying current to a nerve, comprising:

a housing, adapted to be placed in a vicinity of the nerve;

at least one electrode, fixed to the housing such that the at least one electrode does not come in direct physical contact with the nerve, and such that the electrode surrounds greater than 180 degrees of a circumference of the nerve after the placement of the housing; and

two end insulating elements, fixed to the housing;

such that the at least one electrode is between the end insulating elements, and

so as to define a characteristic closest end insulating element distance to a surface of the nerve that is less than 0.5 mm.

2. The apparatus according to claim 1, wherein at least one of the end insulating elements is shaped so as to define a rough surface that is in physical contact with the nerve when the housing is placed in the vicinity of the nerve.

3. The apparatus according to claim 1, wherein the at least one electrode is fixed to the housing so as to define a closest electrode distance to a longitudinal central axis of the nerve that is at least 1 mm.

4. The apparatus according to claim 1, wherein the at least one electrode is fixed to the housing so as to define a closest electrode distance to the surface of the nerve that is at least 0.5 mm.

5. The apparatus according to claim 1, wherein the at least one electrode is fixed to the housing so as to define a closest electrode distance to a longitudinal central axis of the nerve that is at least 1.1 times a radius of the nerve.

6. The apparatus according to claim 1, wherein the at least one electrode is fixed to the housing so as to define a closest electrode distance to a longitudinal central axis of the nerve that is at least 1.5 times a radius of the nerve.

7. The apparatus according to claim 1, wherein the at least one electrode comprises exactly one set of one or more electrodes having respective electrode surfaces that are in electrical contact with the nerve and are in electrical contact with each other via a path outside of the nerve.

8. The apparatus according to claim 1, wherein the housing and the end insulating elements are an integrated unit.

9. The apparatus according to claim 1, wherein the housing is shaped so as to define an external surface, configured to promote growth of fibrous connective tissue therearound.

10. The apparatus according to claim 1, wherein the end insulating elements are shaped so as to define, upon placement of the housing in the vicinity of the nerve, a nerve axial distance between the end insulating elements that is less than an electrode surface axial length of the at least one electrode.

11. The apparatus according to claim 10, wherein the electrode surface axial length is between 1.5 and 5 times the nerve axial distance.

12. The apparatus according to claim 1, wherein at least one of the end insulating elements is shaped so as to define a contact surface between the end insulating element and the nerve, and wherein the contact surface is configured so as to promote connective tissue growth between the nerve and the contact surface.

13. The apparatus according to claim 12, wherein the contact surface is configured so as to promote the connective tissue growth in such a manner so as to provide insulation between the nerve and the contact surface.

14. The apparatus according to claim 12, wherein the contact surface is treated with a growth factor that can promote the connective tissue growth.

15. The apparatus according to claim 12, wherein the contact surface comprises a mesh that is adapted to promote the connective tissue growth.

16. The apparatus according to claim 1, wherein the end insulating elements are fixed to the housing so as to be in physical contact with the nerve after placement of the housing.

17. The apparatus according to claim 16, wherein the end insulating elements are fixed to the housing so as to be in physical contact with the nerve immediately upon the placement of the housing.

18. The apparatus according to claim 16, wherein the end insulating elements are fixed to the housing so as to be in physical contact with the nerve after a period of adaptation of the nerve to the placement of the housing.

19. The apparatus according to claim 16, wherein the end insulating elements are fixed to the housing so as to be in direct physical contact with the nerve.

20. The apparatus according to claim 16, wherein the end insulating elements are adapted to be in indirect physical contact with the nerve via connective tissue that grows after the placement of the housing.

21. The apparatus according to claim 1, wherein the at least one electrode comprises at least a first electrode and a second electrode, and comprising an internal insulating element fixed to the housing between the first and second electrodes, so as to define a closest internal insulating element distance to the surface of the nerve that is less than 0.5 mm.

22. The apparatus according to claim 21, wherein the internal insulating element is fixed to the housing so as to be in physical contact with the nerve after placement of the housing.

23. The apparatus according to claim 1, wherein the at least one electrode comprises at least first, second, and third electrodes, and comprising first and second internal insulating elements fixed to the housing between the first and the second electrodes, and between the second and the third electrodes, respectively, so as to define closest internal insulating element distances to the surface of the nerve that are each less than 0.5 mm.

24. The apparatus according to claim 23, wherein the internal insulating elements are fixed to the housing so as to be in physical contact with the nerve after placement of the housing.

25. The apparatus according to claim 23, wherein the first and second internal insulating elements are shaped to define, upon placement of the housing, a nerve axial distance between the first and second internal insulating elements that is less than an electrode surface axial length of the second electrode.

26. The apparatus according to claim 25, wherein the electrode surface axial length is between 1.5 and 5 times the nerve axial distance.

27. The apparatus according to claim 1, wherein the at least one electrode comprises one or more materials selected from the list consisting of:

platinum, a platinum alloy, titanium, and a titanium alloy.

28. The apparatus according to claim 27, wherein the at least one electrode comprises substantially only the one or more materials.

29. The apparatus according to claim 27, comprising at least one lead coupled to the at least one electrode, the at least one lead comprising:

a first portion thereof within 2 cm of a surface of the at least one electrode closest to the nerve, the first portion comprising substantially only the one or more materials; and

a second portion thereof greater than 2 cm from the surface of the at least one electrode closest to the nerve, the second portion comprising a conductive material.

30. The apparatus according to claim 1, wherein the housing comprises an outer insulating wall not in physical contact with the nerve when the housing is in the vicinity of the nerve, and wherein at least a portion of the outer insulating wall has a hardness greater than a hardness of at least a portion of at least one of the end insulating elements.

31. The apparatus according to claim 30, wherein the at least a portion of the outer insulating wall has a Shore D hardness of between 40 and 50, and wherein the at least a portion of the at least one of the end insulating elements has a Shore D hardness of between 5 and 20.

32. The apparatus according to claim 31, wherein the at least a portion of the end insulating elements has a Shore D hardness of 10.

33. Apparatus for applying current to a nerve, comprising:

a housing, adapted to be placed in a vicinity of the nerve;

first and second electrodes, fixed to the housing at respective first and second longitudinal sites of the housing, such that the first and second electrodes do not come in direct physical contact with the nerve;

an internal insulating element, fixed to the housing between the first and second longitudinal sites; and

two end insulating elements, fixed to the housing;

such that the first and second longitudinal sites are between the end insulating elements, and

so as to define a characteristic closest end insulating element distance to a surface of the nerve that is less than 0.5 mm.

34. Apparatus for applying current to a nerve, comprising:

a housing, adapted to be placed in a vicinity of the nerve;

exactly one set of one or more electrodes fixed to the housing, such that the electrodes do not come in direct physical contact with the nerve, the electrodes having respective electrode surfaces that are in electrical contact with the nerve and are in electrical contact with each other via a path outside of the nerve; and

two end insulating elements, fixed to the housing such that the set of electrodes are between the end insulating elements, so as to define a characteristic closest end insulating element distance to a surface of the nerve that is less than 0.5 mm.

35. The apparatus according to claim 34, wherein at least one of the end insulating elements is shaped so as to define a rough surface that is in physical contact with the nerve when the housing is placed in the vicinity of the nerve.

36. The apparatus according to claim 34, wherein the electrodes are fixed to the housing so as to define a closest electrode distance to a longitudinal central axis of the nerve that is at least 1 mm.

37. The apparatus according to claim 34, wherein the electrodes are fixed to the housing so as to define a closest electrode distance to the surface of the nerve that is at least 0.5 mm.

38. The apparatus according to claim 34, wherein the electrodes are fixed to the housing so as to define a closest electrode distance to a longitudinal central axis of the nerve that is at least 1.1 times a radius of the nerve.

39. The apparatus according to claim 34, wherein the electrodes are fixed to the housing so as to define a closest electrode distance to a longitudinal central axis of the nerve that is at least 1.5 times a radius of the nerve.

40. The apparatus according to claim 34, wherein the electrodes are fixed to the housing so as to define a closest electrode distance to a longitudinal central axis of the nerve that is at least 2 times a radius of the nerve.

41. The apparatus according to claim 34, wherein the housing comprises an outer insulating wall not in physical contact with the nerve when the housing is in the vicinity of the nerve, and wherein at least a portion of the outer insulating wall has a hardness greater than a hardness of at least a portion of at least one of the end insulating elements.

42. The apparatus according to claim 41, wherein the at least a portion of the outer insulating wall has a Shore D hardness of between 40 and 50, and wherein the at least a portion of the at least one of the end insulating elements has a Shore D hardness of between 5 and 20.

43. The apparatus according to claim 42, wherein the at least a portion of the end insulating elements has a Shore D hardness of 10.

44. Apparatus for applying current to a nerve having a radius, the apparatus comprising:

a housing, adapted to be placed in a vicinity of the nerve;

first and second anodes, fixed to the housing; and

a cathode, fixed to the housing between the first and the second anodes so as to define a first distance between a longitudinal center of the first anode and a longitudinal center of the cathode, and a second distance between a longitudinal center of the second anode and the longitudinal center of the cathode, the first and the second distances each at least 1 times the radius of the nerve,

the housing being configured such that circumferentially symmetric current is applied by at least one electrode selected from the set consisting of;

the cathode, the first anode, and the second anode.

45. The apparatus according to claim 44, wherein the first and second distances are each at least 1.5 times the radius of the nerve.

46. The apparatus according to claim 45, wherein the first and second distances are each at least 2 times the radius of the nerve.

47. The apparatus according to claim 44, wherein the housing is shaped to define first, second, and third chambers, the first chamber including therein the first anode, the second chamber including therein the cathode, and the third chamber including therein the second anode.

48. The apparatus according to claim 44,

wherein the housing is shaped to define at least one chamber, the chamber including therein an electrode selected from the set consisting of:

the cathode, the first anode, and the second anode, and

wherein the at least one chamber is shaped to surround more than 180 degrees of a circumference of the nerve.

49. The apparatus according to claim 48, wherein the electrode in the chamber is shaped to surround more than 180 degrees of the circumference of the nerve.

50. A method for applying current to a nerve having a radius, the method comprising:

applying first and second anodal currents in a vicinity of respective anodal longitudinal sites of the nerve;

applying a cathodic current in a vicinity of a cathodic longitudinal site of the nerve that is between the first and the second anodal longitudinal sites, locations of the sites defining;

(a) a first distance, that is between a longitudinal center of the first anodal longitudinal site and a longitudinal center of the cathodic longitudinal site, and (b) a second distance, that is between a longitudinal center of the second anodal longitudinal site and the longitudinal center of the cathodic longitudinal site, the first and the second distances each at least 1 times the radius of the nerve; and

configuring a source of at least one current selected from the set consisting of;

the cathodic current, the first anodal current, and the second anodal current, to apply the selected current as a circumferentially symmetric current.

51. The method according to claim 50, wherein the first and second distances are each at least 1.5 times the radius of the nerve.

52. The method according to claim 51, wherein the first and second distances are each at least 2 times the radius of the nerve.

53. The method according to claim 50, wherein applying the first and second anodal currents comprises applying the first and second anodal currents from respective first and second anodal current application chambers, and wherein applying the cathodic current comprises applying the cathodic current from a cathodic current application chamber, separate from the first and second anodal current application chambers.

54. The method according to claim 50, wherein configuring the source comprises applying the selected current from within a chamber that surrounds more than 180 degrees of a circumference of the nerve.

55. Apparatus for applying current to a nerve having a radius, the apparatus comprising:

a housing, adapted to be placed in a vicinity of the nerve;

first and second anodes, fixed to the housing; and

a cathode, fixed to the housing between the first and the second anodes so as to define a first distance between a longitudinal center of the first anode and a longitudinal center of the cathode, and a second distance between a longitudinal center of the second anode and the longitudinal center of the cathode, the first and the second distances each at least 1 times the radius of the nerve,

wherein the housing is shaped to define at least one chamber, the chamber including therein an electrode selected from the set consisting of;

the cathode, the first anode, and the second anode, and

wherein the at least one chamber is shaped to surround more than 180 degrees of a circumference of the nerve.

56. The apparatus according to claim 55, wherein the electrode in the chamber is shaped to surround more than 180 degrees of the circumference of the nerve.

57. The apparatus according to claim 55, wherein the electrode in the chamber is shaped to surround less than or equal to 180 degrees of the circumference of the nerve.

58. The apparatus according to claim 55, wherein the first and second distances are each at least 1.5 times the radius of the nerve.

59. The apparatus according to claim 58, wherein the first and second distances are each at least 2 times the radius of the nerve.

60. The apparatus according to claim 55, wherein the housing is shaped to define first, second, and third chambers, the first chamber including therein the first anode, the second chamber including therein the cathode, and the third chamber including therein the second anode.

61. A method for applying current to a nerve having a radius, the method comprising:

applying first and second anodal currents in a vicinity of respective anodal longitudinal sites of the nerve;

applying a cathodic current in a vicinity of a cathodic longitudinal site of the nerve that is between the first and the second anodal longitudinal sites, locations of the sites defining;

(a) a first distance, that is between a longitudinal center of the first anodal longitudinal site and a longitudinal center of the cathodic longitudinal site, and (b) a second distance, that is between a longitudinal center of the second anodal longitudinal site and the longitudinal center of the cathodic longitudinal site, the first and the second distances each at least 1 times the radius of the nerve; and

configuring a source of at least one current selected from the set consisting of;

the cathodic current, the first anodal current, and the second anodal current, to apply the selected current from within a chamber that surrounds more than 180 degrees of a circumference of the nerve.

62. The method according to claim 61, wherein the first and second distances are each at least 1.5 times the radius of the nerve.

63. The method according to claim 62, wherein the first and second distances are each at least 2 times the radius of the nerve.

64. The method according to claim 61, wherein applying the first and second anodal currents comprises applying the first and second anodal currents from respective first and second anodal current application chambers, and wherein applying the cathodic current comprises applying the cathodic current from a cathodic current application chamber, separate from the first and second anodal current application chambers.