Multichannel electrode and methods of using same

• US 20030083724A1
• Filed: 10/31/2001
• Published: 05/01/2003
• Est. Priority Date: 10/31/2001
• Status: Active Grant

• Current Assignee: London Health Sciences Centre Research Incorporated, National Research Council Canada
• Original Assignee: National Research Council Canada
• Inventors: Nikumb, Suwas, Jog, Mandar
• Granted Patent: US 7,010,356 B2
• Time in Patent Office: Days
• US Class Current: 607/122
• CPC Class Codes: A61N 1/0536 Preventing neurodegenerative response or inflammatory reaction
• CPC Class Codes: A61N 1/0551 Spinal or peripheral nerve electrodes

Abstract

The invention provides a multichannel electrode (“MC electrode”) which can perform multiple functions such as recording, stimulating and lesioning simultaneously or sequentially upon a single insertion into a target site. In one aspect, the MC electrode further provides imaging and drug delivery capabilities. The invention also provides interface connectors for connecting the MC electrode to external units such as data acquisition and/or stimulation systems. Although the MC electrode and associated connectors and system(s) provide an optimal way to perform deep brain surgical procedures, the MC electrode and associated connectors and system(s) are useful generally in any technique which relies on recording, activating, and/or inhibiting electrical signals produced by cells.

Claims

1. A multichannel electrode comprising:

a non-planar backbone comprising a plurality of electrode channels disposed thereon, wherein at least one of said channels has an impedance suitable for recording an electrical signal from a cell and wherein at least one other channel has an impedance suitable for electrical stimulation of a cell.

2. The multichannel electrode according to claim 1, wherein said non-planar backbone is substantially cylindrical.

3. The multichannel electrode according to claim 1, wherein said backbone is flexible or semi-flexible.

4. The multichannel electrode according to claim 1, wherein said backbone comprises a first and second end and wherein said second end tapers to a tip.

5. The multichannel electrode according to claim 4, wherein said tip is substantially conical or frustoconical.

6. The multichannel electrode according to claim 1, wherein said backbone comprises a non-conductive material and a layer of electrically conductive material comprising said channels on top of said non-conductive material.

7. The multichannel electrode according to claim 1, wherein there is an adhesive layer between said non-conductive material and said layer of electrically conductive material.

8. The multichannel electrode according to claim 1, wherein said backbone comprises a lumen.

9. The multichannel electrode according to claim 1 or claim 8, wherein said backbone comprises a light path for transmitting light.

10. The multichannel electrode according to claim 9, wherein said backbone is an optical fiber or light guide.

11. The multichannel electrode according to claim 8, wherein said backbone is coupleable to a fluid delivery pump for delivering a fluid to a target site.

12. The multichannel electrode according to claim 1, wherein said electrode is at least partially contained within a probe housing.

13. The multichannel electrode according to claim 1, wherein said plurality of channels comprise sets of channels, each set comprising at least two channels, and wherein each set is electrically insulated from other sets.

14. The multichannel electrode according to claim 13, wherein at least one of said sets comprises four channels.

15. The multichannel electrode according to claim 14, wherein at least one of said sets comprising four channels comprises at least two channels which are at least partially non coplanar.

16. The multichannel electrode according to claim 15, wherein at least one of said sets comprising four channels comprises two electrodes which are at least partially non-coplanar with either of the remaining two electrodes.

17. The multichannel electrode according to claim 15, wherein said backbone comprises a second end comprising a conical or frustoconical tip, and wherein said tip comprises a base portion adjacent to a substantially cylindrical portion of the backbone and a tip portion comprising a diameter which is smaller than the base portion, and wherein at least one of said sets comprising four channels comprises at least one channel which extends past the base portion of the tip and at least one channel which does not extend past the base portion of the tip.

18. The multichannel electrode according to claim 13 wherein at least one of said sets of channels has an impedance suitable for recording and at least one of said sets of channels has an impedance suitable for stimulating.

19. The multichannel electrode according to claim 18, wherein at least one of said sets of channels has an impedance suitable for lesioning.

20. The multichannel electrode according to claim 1, wherein said backbone comprises a second end comprising a conical or frustoconical tip, wherein said tip comprises a base portion adjacent to a substantially cylindrical portion of the backbone and a tip portion comprising a diameter which is smaller than the base portion, and wherein said channels extend at least the length of the substantially cylindrical portion of the backbone.

21. The multichannel electrode of claim 20, wherein at least a portion of at least one of said channels extends past the base portion of the tip.

22. The multichannel electrode of claim 21, wherein the substantially cylindrical portion of the backbone is covered by an insulating material.

23. The multichannel electrode of claim 22, wherein at least a portion of a channel on the tip is not covered with an insulating material.

44. A method of monitoring the activity of one or more cells at a target site by recording electrical potentials of the one or more cells and/or modulating the activity of one or more cells, comprising bringing an MC electrode according to claim 1 in electrical proximity to the one or more cells and recording the activity of the one or more cells using said at least one channel with an impedance suitable for recording.

45. The method according to claim 44, wherein recorded activity is compared to the activity of a cell with one or more known physiological properties.

46. The method according to claim 45, wherein said cell with one or more known physiological properties is a normally functioning cell and said recorded activity is indicative of the presence of a malfunctioning cell.

47. The method of claim 45, wherein recording is used to determine the anatomical location of said malfunctioning cell.

48. The method according to claim 47, wherein said at least one channel with an impedance suitable for stimulating is activated to deliver an electrical stimulus to said cell.

49. The method according to claim 48, wherein said stimulus activates said cell.

50. The method according to claim 48, wherein said stimulus inhibits said cell.

51. The method according to claim 48, wherein said stimulus permanently disables said cell.

52. The method according to claim 48, wherein said stimulus is used to treat a neurological disorder which is associated with the abnormal electrical activity of one or more neural cells.

53. The method according to claim 52, wherein said disorder is selected from the group consisting of Parkinson'"'"'s disease, motor dysfunction;

spasticity;

a tremor disorder;

dystonia;

a mood disorder;

hypothalmic obesity;

incontinence;

stroke;

epilepsy;

chronic pain;

cancer; and

a spinal cord injury.

54. The method for acute treatment of one or more cells with abnormal electrical activity, comprising:

bringing the multichannel electrode according to claim 1 in electrical proximity to one or more cells;

localizing target cells in need of such treatment by identifying abnormal electrical activity using said at least one channel of said multichannel electrode comprising an impedance suitable for recording;

normalizing said abnormal electrical activity by delivering at least one stimulus from said at least one channel of said multichannel electrode comprising an impedance suitable for stimulating; and

removing said multichannel electrode from electrical proximity of said one or more cells.

55. A method for chronic treatment of cells with abnormal electrical activity, comprising:

bringing a multichannel electrode according to claim 1 in proximity to one or more cells;

localizing target cells in need of such treatment by identifying abnormal electrical activity using said at least one channel of said multichannel electrode comprising an impedance suitable for recording;

normalizing said abnormal electrical activity by delivering at least one stimulus from said at least one channel of said multichannel electrode comprising an impedance suitable for stimulating; and

maintaining the position of the electrode with respect to said one or more cells, monitoring the activity of said one or more cells, and stimulating the cells as necessary to maintain normalized electrical activity.

56. A method for regulating drug delivery to a target site, comprising:

bringing the multichannel electrode according to claim 1 in electrical proximity to one or more cells at a target site being contacted with a drug;

identifying abnormal electrical activity of cells at said target site using said at least one channel of said multichannel electrode comprising an impedance suitable for recording;

changing the amount of drug provided to said target site.

57. The method according to claim 56, wherein said drug is being delivered through a lumen in the backbone of said multichannel electrode.

64. An interfacing connector for interfacing a multichannel electrode according to claim 1 with one or more external devices, said one or more external devices selected from the group consisting of an amplifier, a suction device, a data acquisition system, a drive device, microdrive device, a processor, a light source, an oscilloscope, a detector, a fluid delivery pump, an amplifier, filter, a power supply, an implantable stimulator and/or recording device, and an interfacing cable.

65. The interfacing connector according to claim 64, wherein said connector comprises a plurality of wires, each wire connected to a channel of said multichannel electrode at one end and connectable to at least one external system at another end.

66. The connector according to claim 64, comprising a housing with an inner wall and an outer wall and having a first and second end, wherein said first end is proximal to the MC electrode and said second end is coupleable to at least one external device.

67. The connector according to claim 66, wherein said inner wall defines a central opening into which the first end of the MC electrode can be placed to form electrical contacts with each of a plurality of central terminals which extend from the outer wall to form the inner wall.

24. A system comprising an interfacing connector for connecting to a multichannel electrode comprising a plurality of channels, at least one channel comprising an impedance suitable for recording and at least one channel suitable for stimulating, said connector comprising:

a housing comprising,

a first end and a second end, said first end for connecting to a device for communicating with said multichannel electrode, said second end for receiving said multichannel electrode;

a wall defining a lumen for receiving said multichannel electrode and comprising a plurality of contact points, wherein there is at least one contact point for each channel of said multichannel electrode, and wherein each contact point can transmit an electrical signal to the channel or receive an electrical signal from the channel.

25. An MC electrode system comprising the interfacing connector according to claim 24, coupled to said MC electrode at said second end of said interfacing connector.

26. The system according to claim 24, wherein said connector is coupled to a drive device for controlling the movement of said MC electrode.

27. The system according to claim 24, wherein said connector is coupled to an amplifier for amplifying a signal from said MC electrode.

28. The system according to claim 27, wherein said amplifier is a multichannel amplifier for amplifying signals from a plurality of channels in said MC electrode.

29. The system according to claim 26 or 27, wherein said amplifier is within said housing of said interfacing connector.

30. The system according to claim 27 or 28, wherein said housing is coupled to said first end of said multichannel electrode.

31. The system according to claim 24, wherein said interfacing connector comprises a plurality of resistors for modulating the impedance of said channels of said multichannel electrode.

32. The system according to claim 24, wherein said interfacing connector is in communication with a processor.

33. The system according to claim 32, wherein said processor comprises a data acquisition system.

34. The system according to claim 24, wherein said interfacing connector is coupled to a fluid delivery pump.

35. The system according to claim 24, wherein said interfacing connector is coupled to a stimulator device which comprises a controller for controlling the delivery of stimuli from one or more channels on the electrode to a target site.

36. The system according to claim 35, wherein stimuli can be delivered simultaneously or sequentially.

37. The system according to claim 35, wherein said stimulator device is implantable.

38. The system according to claim 32, wherein said processor is in communication with a computer comprising a display.

39. The system according to claim 24, wherein said interfacing connector is in optical communication with a light source and maintains a light path between the light source and a light path provided by the multichannel electrode for transmitting light from the light source to a target and for receiving light from the target.

40. The system according to claim 39, wherein the light path provided by the multichannel electrode is an optical fiber.

41. The system according to claim 39, wherein said system further comprises a detector in optical communication with a received light path provided by the multichannel electrode.

42. The system according to claim 41, wherein said detector converts optical signals obtained from said multichannel electrode into signals which can be translated into an image of the target site by a processor in communication with the detector.

43. The system according to claim 42, further comprising a computer comprising a display in communication with said processor and wherein said display displays an image of the target site.

58. A method of fabricating a multichannel electrode, said method comprising the steps of:

a) providing a non-planar backbone;

b) coating said non-planar backbone with an electrically conductive material; and

c) laser micro-machining a plurality of channels into said electrically conductive material;

wherein at least one channel comprises an impedance suitable for recording electrical activity of a cell, and wherein at least one channel comprises an impedance suitable for stimulating the electrical activity of a cell.

59. A method of fabricating fabricating a multichannel electrode, said method comprising the steps of:

a) providing a first non-planar backbone comprising a lumen;

b) coating said non-planar backbone with an electrically conductive material;

c) laser micro-machining a plurality of channels into said electrically conductive material;

d) providing a second non-planar backbone within said lumen of said first non-planar backbone, said second non-planar backbone coated with an electrically conductive material and comprising a plurality of electrode channels machined thereon;

wherein at least one channel of said multichannel electrode comprises an impedance suitable for recording electrical activity of a cell, and wherein at least one channel comprises an impedance suitable for stimulating the electrical activity of a cell; and

(e) placing said second backbone within said lumen of said first backbone.

60. A multichannel electrode comprising:

a first non-planar backbone comprising a lumen; and

a second non-planar backbone disposed within the lumen of the first non-planar backbone;

said first and second backbone each comprising at least one electrode channel, wherein at least one of said channels has an impedance suitable for recording an electrical signal from a cell and wherein at least one other of said channels has an impedance suitable for electrical stimulation of a cell.

61. The multichannel electrode according to claim 60, wherein said first non-planar backbone is formed by rolling a flexible sheet around said second non-planar backbone.

62. The multichannel electrode according to claim 60, comprising at least two sets of channels wherein at least one of said sets of channels has an impedance suitable for recording and at least one of said sets of channels has an impedance suitable for stimulating.

63. The multichannel electrode according to claim 60, wherein at least one channel of a set is on said first backbone and at least one other channel of said set is on said second backbone.