Vagus nerve stimulation via unidirectional propagation of action potentials

• US 20030236558A1
• Filed: 06/20/2002
• Published: 12/25/2003
• Est. Priority Date: 06/20/2002
• Status: Active Grant

• Current Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Inventors: Carbunaru, Rafael, Whitehurst, Todd K., Haller, Matthew I., McGivern, James P., Bradley, Kerry, Xiaohai He, Tom
• Granted Patent: US 7,292,890 B2
• Time in Patent Office: Days
• US Class Current: 607/45
• CPC Class Codes: A61N 1/0551 Spinal or peripheral nerve electrodes
• CPC Class Codes: A61N 1/0556 Cuff electrodes
• CPC Class Codes: A61N 1/36071 Pain
• CPC Class Codes: Y10S 128/903 Radio telemetry

Abstract

Methods of using unidirectionally propagating action potentials (UPAPs) for vagus nerve stimulation and for certain disorders are provided. Stimulators capable of creating such UPAPs include, but are not limited to, miniature implantable stimulators (i.e., microstimulators), possibly with programmably configurable electrodes.

Claims

1. Method of stimulating a vagus nerve, comprising:

providing at least one implantable stimulator with at least two electrodes;

configuring the electrodes to apply stimulation that unidirectionally propagates action potentials along a vagus nerve;

applying the stimulation to the vagus nerve to effectively select afferent fibers, thereby treating at least one of epilepsy and depression while limiting side effects of bidirectional stimulation.

2. The method of claim 1 wherein providing at least one implantable stimulator comprises providing at least one microstimulator.

3. The method of claim 1 further comprising applying the stimulation at less than about 50-100 Hz.

4. The method of claim 1 further comprising applying the stimulation with a stimulation pulse with at least one of a plateau pulsewidth of about 10 μ

sec to about 5 msec and a decaying trailing phase with a fall time of about 50 μ

sec to about 5 msec and a charge recovery pulse with at least one of a plateau pulsewidth of about 50 μ

sec to about 10 msec and a decaying trailing phase with a fall time of about 50 μ

sec to about 5 msec.

5. The method of claim 1 wherein at least one of the electrodes is a virtual electrode.

6. The method of claim 1 wherein the stimulator includes at least three electrodes.

7. The method of claim 6 wherein at least one of the electrodes is a virtual electrode.

8. The method of claim 1 further comprising sensing at least one physical condition of a patient.

9. The method of claim 8 wherein the at least one sensed physical condition includes at least one of EEG of the cortex, EEG of the thalamus, EEG of a region adjacent to a scarred region of the brain, EEG of an area of the brain known to give rise to a seizure in a particular patient, limb EMG, and action potentials propagating along the vagus nerve.

10. The method of claim 8 further comprising determining at least one of the electrode configuration and the stimulation to apply based on the at least one physical condition of the patient.

11. Method of stimulating a vagus nerve, comprising:

providing at least one implantable stimulator with at least two electrodes;

configuring the electrodes to apply stimulation that unidirectionally propagates the action potentials along a vagus nerve;

applying the stimulation to the vagus nerve to effectively select efferent fibers, thereby treating tachycardia while limiting side effects of bidirectional stimulation.

12. The method of claim 11 wherein providing at least one implantable stimulator comprises providing at least one microstimulator.

13. The method of claim 11 further comprising applying the stimulation at less than about 50-100 Hz.

14. The method of claim 11 further comprising applying the stimulation with a stimulation pulse with at least one of a plateau pulsewidth of about 10 μ

sec to about 5 msec and a decaying trailing phase with a fall time of about 50 μ

sec to about 5 msec and a charge recovery pulse with at least one of a plateau pulsewidth of about 50 μ

sec to about 10 msec and a decaying trailing phase with a fall time of about 50 μ

sec to about 5 msec.

15. The method of claim 11 wherein at least one of the electrodes is a virtual electrode.

16. The method of claim 11 wherein the stimulator includes at least three electrodes.

17. The method of claim 16 wherein at least one of the electrodes is a virtual electrode.

18. The method of claim 11 further comprising sensing at least one physical condition of a patient.

19. The method of claim 18 wherein the at least one sensed physical condition includes at least one of ECG, heart rate, blood pressure, blood flow, cardiac output, acceleration, breathing, and action potentials propagating along the vagus nerve.

20. The method of claim 18 further comprising determining at least one of the electrode configuration and the stimulation to apply based on the at least one physical condition of the patient.

21. Method of stimulating a vagus nerve, comprising:

providing at least one implantable stimulator with at least two electrodes;

configuring the electrodes to apply stimulation that unidirectionally propagates action potentials along a vagus nerve;

applying the stimulation to the vagus nerve to effectively select orthodromic action potentials traveling in one direction along the nerve, thereby limiting side effects of bidirectional stimulation.

22. The method of claim 21 wherein providing at least one implantable stimulator comprises providing at least one microstimulator.

23. The method of claim 22 wherein the at least one microstimulator comprises a programmably configurable microstimulator with at least two activated electrodes configured as a first cathode and a first anode.

24. The method of claim 21 wherein the electrodes comprise at least a first cathode and a first anode, and the method further comprises:

applying a depolarizing cathodic current to a nerve via the first cathode, which cathodic current is sufficient to initiate bidirectional action potentials in large diameter nerve fibers and small diameter nerve fibers;

applying a hyperpolarizing anodic current to the nerve via the first anode at a side of the cathode where arrest of the action potentials is desired; and

tapering the anodic current.

25. The method of claim 24 further comprising applying the hyperpolarizing current before the action potentials pass the first anode, which hyperpolarizing current is relatively high-amplitude hyperpolarizing current, which high-amplitude hyperpolarizing current is sufficient to arrest action potentials in large diameter nerve fibers and small diameter nerve fibers.

26. The method of claim 24 further comprising waiting an amount of time allowing the action potentials to propagate in the large diameter nerve fibers, then applying the hyperpolarizing anodic current to the nerve at the side of the cathode where arrest of the action potentials in the small diameter nerve fibers is desired, which hyperpolarizing current arrests action potentials in the small diameter nerve fibers.

27. The method of claim 24 further comprising applying the hyperpolarizing current before the action potentials pass the first anode, which hyperpolarizing current is a relatively low-amplitude hyperpolarizing current, which low-amplitude hyperpolarizing current is sufficient to arrest action potentials in large diameter nerve fibers and allows propagation of action potentials in small diameter nerve fibers.

28. Method of stimulating a vagus nerve, comprising the steps of:

providing at least one implantable stimulator with at least two electrodes;

configuring the electrodes to apply stimulation that unidirectionally propagates action potentials along a vagus nerve;

applying the stimulation to the vagus nerve to effectively select orthodromic action potentials traveling in one direction along the nerve, thereby limiting side effects of bidirectional stimulation.

29. The method of claim 28 wherein providing at least one implantable stimulator comprises providing at least one microstimulator.

30. The method of claim 29 wherein the at least one microstimulator comprises a programmably configurable microstimulator with at least two activated electrodes configured as a first cathode and a first anode.

31. The method of claim 28 wherein the electrodes comprise at least a first cathode and a first anode, and the method further comprises:

applying a depolarizing cathodic current to a nerve via the first cathode, which cathodic current is sufficient to initiate bidirectional action potentials in large diameter nerve fibers and small diameter nerve fibers;

applying a hyperpolarizing anodic current to the nerve via the first anode at a side of the cathode where arrest of the action potentials is desired; and

tapering the anodic current.