CAVERNOUS NERVE STIMULATION VIA UNIDIRECTIONAL PROPAGATION OF ACTION POTENTIALS

• US 20070021800A1
• Filed: 09/28/2006
• Published: 01/25/2007
• Est. Priority Date: 06/20/2002
• Status: Active Grant

• Current Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Original Assignee: Advanced Bionics Corporation (Sonova Holding AG)
• Inventors: Carbunaru, Rafael, Bradley, Kerry, He, Tom, Haller, Matthew, McGivern, James, Whitehurst, Todd
• Granted Patent: US 7,899,539 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: A61N 1/37205 Microstimulators, e.g. implantable through a cannula

Abstract

Methods of using unidirectionally propagating action potentials (UPAPs) for cavernous 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 cavernous nerve, the method comprising:

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

programming stimulation parameters for the cathodic electrodes to radially steer an electric field generated by the cathodic electrodes to apply stimulation that unidirectionally propagates action potentials along a cavernous nerve; and

applying the stimulation to the cavernous nerve in accordance with the stimulation parameters to generate orthodromic action potentials traveling in one direction along the nerve,

thereby limiting side effects of bidirectional stimulation.

2. The method of claim 1 wherein applying the stimulation to the cavernous nerve comprises applying the stimulation to efferent fibers, thereby treating erectile dysfunction while limiting side effects of bidirectional stimulation.

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

4. The method of claim 3 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.

5. The method of claim 1 wherein the cavernous nerve comprises at least one cavernous nerve, including the left cavernous nerves, the right cavernous nerves, branches of the left cavernous nerves, branches of the right cavernous nerves, nerves that give rise to at least one cavernous nerve, and neurovascular bundles containing at least one cavernous nerve.

6. The method of claim 1 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.

7. The method of claim 6 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.

8. The method of claim 6 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;

9. The method of claim 6 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.

10. A method comprising:

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

programming stimulation parameters to radially steer an electric field generated by the electrodes to apply stimulation to a cavernous nerve;

applying the stimulation to the cavernous nerve at a first position using at least one of the cathodic electrodes;

attempting to hyperpolarize the cavernous nerve at a second position using an anodic electrode;

detecting a physiological condition characteristic of propagation of an action potential generated in response to the depolarization of the cavernous nerve past the second position;

reprogramming stimulation parameters used by the implanted stimulator to hyperpolarize the cavernous nerve.

11. The method of claim 10, wherein reprogramming the stimulation parameters to hyperpolarize the cavernous nerve comprises selecting a selecting a second anodic electrode to hyperpolarize the cavernous nerve.

12. The method of claim 10, wherein detecting the physiological condition comprises detecting the action potential at a position past the second position.

13. The method of claim 12, wherein detecting the action potential comprises detecting the action potential in relatively small diameter fibers of the cavernous nerve.

14. The method of claim 10, wherein the cathodic electrodes are distributed along an outer surface of an elongate capsule of the implanted stimulator

15. The method of claim 10, further comprising implanting the stimulator using a minimal surgical procedure.

16. A method comprising:

stimulating a cavernous nerve by selecting a subset of a collection of electrodes positioned at different locations along a short axis of an implanted microstimulator to direct electrical stimulation applied by the implanted microstimulator to a position along the cavernous nerve, said selecting being done in accordance with a set of stimulation parameters;

in response to a perceived reduction of stimulation of the cavernous nerve, transmitting to the implanted microstimulator data indicating that at least some of the stimulation parameters in the set are to change; and

stimulating the cavernous nerve by redirecting the electrical stimulation applied by the implanted microstimulator by steering the electrical stimulation among at least the subset of the collection of electrodes in accordance with the changes to the stimulation parameters to steer the electrical stimulation around the short axis of the microstimulator.

17. The method of claim 16, further comprising identifying reduced stimulation of the cavernous nerve by sensing arterial pressure in the penis.

18. The method of claim 16, further comprising identifying reduced stimulation of the cavernous nerve by sensing tumescence in the penis.

19. The method of claim 16, wherein stimulating the cavernous nerve comprises unidirectionally stimulating the cavernous nerve.

20. The method of claim 19, wherein unidirectionally stimulating the cavernous nerve comprises hyperpolarizing the cavernous nerve at a position between the central nervous system and the stimulation site of the cavernous nerve.

21. The method of claim 17, wherein the redirected electrical stimulation stimulates substantially the same position along the cavernous nerve.