Method for epidural stimulation of neural structures
View Patent ↗A method for treating a patient having nociceptive pain in a body region using at least one electrode implanted within a spinal column of the patient. The method comprises conveying electrical stimulation energy from the at least one implanted electrode to an efferent motor neural structure innervating the body region, thereby inducing an endogenous chemical response within a spinal cord of the patient that treats the nociceptive pain. Another method for treating a patient suffering from a medical ailment. The other method comprises applying electrical stimulation energy to an efferent neural structure, thereby increasing the activation threshold of the efferent neural structure relative an afferent neural structure, and applying electrical stimulation energy to the afferent neural structure while the activation threshold of the efferent neural structure is increased, thereby modulating activity of the afferent neural structure to treat the medical ailment while minimizing stimulation of the efferent neural structure.
1. A method for treating a patient suffering from a medical ailment using at least one electrode adjacent an efferent neural structure and at least another electrode adjacent an afferent neural structure, the method comprising:
applying electrical stimulation energy by the at least one electrode to the efferent neural structure, thereby increasing the activation threshold of the efferent neural structure relative the afferent neural structure; and
applying electrical stimulation energy by the at least other electrode to the afferent neural structure while the activation threshold of the efferent neural structure is increased, thereby modulating activity of the afferent neural structure to treat the medical ailment, wherein the increasing of the activation threshold of the efferent neural structure minimizes any stimulation of the efferent neural structure inadvertently caused by the electrical stimulation energy applied by the at least one other electrode to the efferent neural structure.
2. The method of claim 1 , wherein the medical ailment is chronic pain.
3. The method of claim 1 , wherein stimulation of the efferent neural structure that would otherwise occur absent the increased activation threshold is prevented.
4. The method of claim 1 , wherein the electrical stimulation energy is epidurally applied to the afferent neural structure and the efferent neural structure.
5. The method of claim 1 , wherein the efferent neural structure is a ventral root fiber.
6. The method of claim 5 , wherein the afferent neural structure is a dorsal root fiber.
7. The method of claim 5 , wherein the afferent neural structure is one of a dorso-spinal column fiber, dorso-lateral spinal column fiber, and a ventro-lateral spinal column fiber.
8. The method of claim 1 , wherein the activation threshold of the efferent neural structure relative to the activation threshold of the afferent neural structure is increased by applying electrical suppression energy by the at least one electrode to the efferent neural structure.
9. The method of claim 8 , wherein the electrical stimulation energy is applied to the afferent neural structure by sinking electrical current into the at least one other electrode adjacent the afferent neural structure, thereby treating the medical ailment, and the electrical suppression energy is applied to the efferent neural structure by sourcing at least a portion of the electrical current from the at least one electrode adjacent the efferent neural structure, thereby increasing the activation threshold of the efferent neural structure.
10. The method of claim 8 , further comprising sinking at least a portion of the electrical current sourced at the at least one electrode into a remote electrode.
11. The method of claim 8 , wherein the activation threshold of the efferent neural structure is increased by applying a sub-threshold, disabling conditioning pre-pulse by the at least one electrode to the efferent neural structure, and electrical stimulation energy is applied by the at least one other electrode to the afferent neural structure by applying a depolarizing stimulation pulse to the afferent neural structure.
12. The method of claim 11 , wherein the conditioning pre-pulse is a hyperpolarizing pulse having a duration less than 200 μs.
13. The method of claim 1 , wherein the activation threshold of the efferent neural structure is increased by applying electrical background energy by the at least one electrode to the efferent neural structure in accordance with at least one stochastic parameter.
14. The method of claim 13 , wherein the electrical background energy comprises pulses, and the at least one stochastic parameter comprises at least one of an interpulse interval, pulse amplitude, pulse shape, and pulse duration.
15. The method of claim 13 , wherein the electrical background energy comprises white noise, and the at least one stochastic parameter comprises a frequency.
16. The method of claim 1 , further comprising sensing neural activity in the efferent neural structure in response to the application of electrical stimulation energy to the afferent neural structure by the at least other electrode, wherein the electrical stimulation energy is applied to the efferent neural structure by the at least one electrode in response to sensing of the neural activity in the efferent neural structure.