ONSET-MITIGATING HIGH-FREQUENCY NERVE BLOCK

• US 20100241190A1
• Filed: 10/28/2008
• Published: 09/23/2010
• Est. Priority Date: 10/29/2007
• Status: Active Grant

• Current Assignee: Case Western Reserve University
• Original Assignee: Case Western Reserve University
• Inventors: Kilgore, Kevin L., Bhadra, Niloy
• Granted Patent: US 8,983,614 B2
• Time in Patent Office: Days
• US Class Current: 607/48
• CPC Class Codes: A61N 1/0551 Spinal or peripheral nerve electrodes
• CPC Class Codes: A61N 1/20 continuous direct currents
• CPC Class Codes: A61N 1/205 for promoting a biological process
• 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 1/36057 adapted for stimulating afferent nerves
• CPC Class Codes: A61N 1/36067 Movement disorders, e.g. tremor or Parkinson disease stimulating motor muscle A61N1/36003
• CPC Class Codes: A61N 1/36071 Pain
• CPC Class Codes: A61N 1/36103 Neuro-rehabilitation; Repair or reorganisation of neural tissue, e.g. after stroke
• CPC Class Codes: A61N 1/3615 Intensity
• CPC Class Codes: A61N 1/36167 Timing, e.g. stimulation onset
• CPC Class Codes: A61N 1/36171 Frequency

Abstract

A method of blocking signal transmission through a nerve with reduced onset activity includes applying an HFAC to an axon of a nerve to block the transmission of signals through the axon. The method may also include applying a direct current (DC) to the axon, increasing the amplitude of the DC over time to a predetermined amplitude, applying the HFAC, and then decreasing the DC. The method may also include temporarily reducing the amplitude of the HFAC to permit the transmission of signals through the axon and subsequently increasing the amplitude to block transmission without triggering an onset response. The method may also include temporarily applying an unbalanced charge to the nerve and then balancing the charge over time.

Claims

1-38. -38. (canceled)

39. A method, comprising:

providing one or more transition waveforms to a nerve to manage an onset activity in the nerve; and

providing at least one steady-state waveform to block nerve signal transmission in the nerve.

40. The method of claim 39, where the one or more transition waveforms deliver electrical charge of either polarity.

41. The method of claim 39, where the at least one steady-state waveform delivers a zero net charge.

42. The method of claim 39, comprising providing the one or more transition waveforms and the steady state waveform through a single electrode.

43. The method of claim 39, where the one or more transition waveforms and the steady state waveform deliver electrical charge in an amount that does not produce an action potential in the nerve.

44. The method of claim 39, where the one or more transition waveforms are imbalanced, and where the method includes recovering at least a portion of an imbalanced charge over a period of time.

45. The method of claim 39, where the at least one steady state waveform is imbalanced, and where the method includes recovering at least a portion of an imbalanced charge over a period of time.

46. The method of claim 39, where the one or more transition waveforms initially vary in one or more of, offset, amplitude, and frequency, and where the method comprises altering the one or more transition waveforms to a charge-balanced waveform.

47. An apparatus, comprising:

an electrode;

a waveform generator connected to the electrode; and

a controller configured to;

first control the waveform generator to generate a DC ramp and to apply the DC ramp to a nerve through the electrode;

then control the waveform generator to generate a first alternating waveform and to apply the first alternating waveform to the nerve through the electrode, where the first alternating waveform has an increasing amplitude, and where the first alternating waveform has one of, a cathodic offset, and an anodic offset;

then control the waveform generator to generate a second alternating waveform and to apply the second alternating waveform to the nerve through the electrode, where the second alternating waveform has one of, a cathodic offset that ramps to zero, and an anodic offset that ramps to zero;

then control the waveform generator to generate a steady state, HFAC waveform and to apply the steady state HFAC waveform to the nerve through the electrode.

48. An apparatus, comprising:

an electrode;

a waveform generator connected to the electrode; and

a controller configured to;

control the waveform generator to first apply a first high frequency alternating current (HFAC) to a nerve through the electrode, the first HFAC having a first amplitude and a first frequency, the combination of the first amplitude and the first frequency being configured to produce a conduction block in the nerve, where the conduction block blocks transmission of signals through the nerve;

control the waveform generator to then apply a second HFAC to the nerve, the second HFAC having a second amplitude and a second frequency, the combination of the second amplitude and the second frequency being configured to not produce a nerve conduction block in the nerve, the combination of the second amplitude and the second frequency being configured to prevent the occurrence of an onset condition in the nerve upon the application of a third HFAC sufficient to produce a conduction block in the nerve; and

control the waveform generator to then apply the third HFAC to the nerve, the third HFAC having a third amplitude and a third frequency, the combination of the third amplitude and the third frequency being configured to produce a conduction block in the nerve.

49. The apparatus of claim 48, where the first frequency and the third frequency are in the range of 1 kiloHertz to 100 kiloHertz.

50. The apparatus of claim 49, where the nerve conduction block is one of, a motor nerve block, a sensing nerve block, an autonomic block, a sternocleidomastoid block, a median nerve block, a phrenic nerve block, a celiac plexus nerve block, and a modulated spasticity block, and where the nerve conduction block is applied to treat symptoms of one or more of, torticollis, neuroma pain, hiccups, muscular dystrophy, cancer pain, post-operative pain, chronic pain, pain, and stroke.

51. The apparatus of claim 49, where the waveform generator is controlled to selectively apply one or more of, the first HFAC, the second HFAC, and the third HFAC based, at least in part, on a control signal received from a closed loop control apparatus.

52. The apparatus of claim 49, where one or more of, the first HFAC, the second HFAC, and the third HFAC are initially unbalanced with respect to charge and where the waveform generator is controlled to balance, over a period of time, the charge of an initially unbalanced HFAC.

53. The apparatus of claim 52, where the waveform generator is controlled to vary the amplitude of the initially unbalanced HFAC over the period of time during which the charge of the initially unbalanced HFAC is being balanced.

54. An apparatus, comprising:

an electrode;

a waveform generator connected to the electrode; and

a controller configured to;

control the waveform generator to first apply a direct current (DC) to an axon of a nerve, the DC having a first DC amplitude, the DC having the first amplitude not being sufficient to produce a nerve block in the axon;

then control the waveform generator to alter the DC over a first period of time by changing the first DC amplitude to a second DC amplitude, the DC having the second DC amplitude being sufficient to produce a conduction block in the nerve;

then control the waveform generator to apply a high frequency alternating current (HFAC) to the nerve, the HFAC having an HFAC amplitude and an HFAC frequency, the HFAC being configured to produce a conduction block in the nerve; and

then control the waveform generator to alter the DC over a second period of time by changing the second DC amplitude to a third DC amplitude, the DC having the third DC amplitude not being sufficient to produce a conduction block in the nerve;

where the combination of the DC and the HFAC and the order in which the DC and the HFAC are applied reduce an onset activity in the nerve associated with producing a conduction nerve block when compared to the onset activity in the nerve if only the HFAC was applied.

55. The apparatus of claim 54, the electrode comprising a four node electrode, the four node electrode comprising a set of two inner nodes for applying an HFAC and a set of two outer nodes for applying a DC.

56. The apparatus of claim 54, the electrode comprising a three node electrode, the three nodes comprising a set of two outer nodes for applying both the HFAC and DC together, and the center node for applying the HFAC only.

57. The apparatus of claim 54, where the HFAC frequency is in the range of 1 kiloHertz to 100 kiloHertz.

58. The apparatus of claim 54, where the nerve conduction block is one of, a motor nerve block, a sensing nerve block, an autonomic block, a sternocleidomastoid block, a median nerve block, a phrenic nerve block, a celiac plexus nerve block, and a modulated spasticity block, and where the nerve conduction block is applied to treat symptoms of one or more of, torticollis, neuroma pain, hiccups, muscular dystrophy, cancer pain, post-operative pain, chronic pain, pain, and stroke.