ENERGY EFFICIENT HIGH FREQUENCY NERVE BLOCKING TECHNIQUE

• US 20120016448A1
• Filed: 07/15/2011
• Published: 01/19/2012
• Est. Priority Date: 07/15/2010
• Status: Active Grant

• Current Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Inventors: Lee, Dongchul
• Granted Patent: US 9,782,592 B2
• Time in Patent Office: Days
• US Class Current: 607/72
• CPC Class Codes: A61N 1/0553 Paddle shaped electrodes, e.g. for laminotomy
• CPC Class Codes: A61N 1/36062 Spinal stimulation
• CPC Class Codes: A61N 1/3615 Intensity
• CPC Class Codes: A61N 1/36171 Frequency

Abstract

A neurostimulation system and method of blocking a neural axon. Time-varying electrical energy is conveyed to a blocking site on the neural axon for an initial phase. The conveyed electrical energy has an amplitude and frequency during the initial phase sufficient to block action potentials from propagating along the neural axon from a location proximal to the blocking site to a location distal to the blocking site. The time-varying electrical energy is conveyed to the blocking site on the neural axon for a subsequent phase contiguous with the initial phase. The conveyed electrical energy has a decreased amplitude and a frequency during the subsequent phase sufficient to maintain blocking of the action potentials along the neural axon from the location proximal to the blocking site to the location distal to the blocking site.

Claims

1. A neurostimulation system, comprising:

at least one electrical terminal configured for being respectively coupled to at least one electrode locatable adjacent a blocking site of a neural axon;

analog output circuitry configured for conveying time-varying electrical energy to the at least one electrical terminal; and

control circuitry configured for instructing the analog output circuitry to convey the time-varying electrical energy during an initial phase and a subsequent phase, wherein the conveyed electrical energy has an amplitude and frequency during the initial phase sufficient to block action potentials from propagating along a neural axon from a location proximal to the blocking site to a location distal to the blocking site; and

the conveyed electrical energy has a decreased amplitude and a frequency during the subsequent phase sufficient to maintain blocking of the action potentials along the neural axon from the location proximal to the blocking site to the location distal to the blocking site.

2. The neurostimulation system of claim 1, wherein the amplitude is uniform during the initial phase.

3. The neurostimulation system of claim 1, wherein the control circuitry is configured for automatically instructing the analog output circuitry to decrease the amplitude from an initial value at the end of the initial phase to a steady-state value during the subsequent phase.

4. The neurostimulation system of claim 3, wherein the subsequent phase is divided into an amplitude adjustment phase and a steady-state phase, and the control circuitry is configured for instructing the analog output circuitry to gradually decrease the amplitude from the initial value to the steady-state value during the amplitude adjustment phase, and for instructing the analog output circuitry to maintain the amplitude at the steady-state value during the steady-state phase.

5. The neurostimulation system of claim 4, wherein the control circuitry is configured for instructing the analog output circuitry to exponentially decrease the amplitude from the initial value to the steady-state value during the amplitude adjustment phase.

6. The neurostimulation system of claim 4, wherein the control circuitry is configured for instructing the analog output circuitry to linearly decrease the amplitude from the initial value to the steady-state value during the amplitude adjustment phase.

7. The neurostimulation system of claim 1, wherein the frequency of the conveyed electrical energy is greater than 2 KHz during the initial phase.

8. The neurostimulation system of claim 1, wherein the frequency of the conveyed electrical energy is in the range of 3 KHz-20 KHz during the initial phase.

9. The neurostimulation system of claim 1, wherein the time-varying electrical energy is sinusoidal.

10. The neurostimulation system of claim 1, wherein the initial phase is in the range of 0.1-20 ms.

11. The neurostimulation system of claim 1, wherein the subsequent phase is greater than the initial phase.

12. The neurostimulation system of claim 1, wherein the frequency of the conveyed electrical energy during the subsequent phase is a decreased frequency.

13. The neurostimulation system of claim 1, further comprising at least another electrical terminal configured for being respectively coupled to at least another electrode locatable adjacent a stimulation site of the neural axon proximal to the blocking site, wherein the analog output circuitry is further configured for conveying stimulation pulses to the at least other electrical terminal, and the control circuitry is further configured for instructing the analog output circuitry to convey the stimulation pulses during the initial phase and the subsequent phase to evoke the action potentials at the stimulation site.

14. The neurostimulation system of claim 1, further comprising the at least one electrode.

15. The neurostimulation system of claim 1, further comprising a housing containing the at least one electrical terminal, the analog output circuitry, and the control circuitry.

16. A method of blocking a neural axon, comprising:

conveying time-varying electrical energy to a blocking site on the neural axon for an initial phase, wherein the conveyed electrical energy has an amplitude and frequency during the initial phase sufficient to block action potentials from propagating along the neural axon from a location proximal to the blocking site to a location distal to the blocking site; and

conveying the time-varying electrical energy to the blocking site on the neural axon for a subsequent phase contiguous with the initial phase, wherein the conveyed electrical energy has a decreased amplitude and a frequency during the subsequent phase sufficient to maintain blocking of the action potentials along the neural axon from the location proximal to the blocking site to the location distal to the blocking site.

17. The method of claim 16, wherein the amplitude is uniform during the initial phase.

18. The method of claim 16, wherein the amplitude is decreased from an initial value at the end of the initial phase to a steady-state value during the subsequent phase.

19. The method of claim 18, wherein the subsequent phase is divided into an amplitude adjustment phase during which the amplitude is gradually decreased from the initial value to the steady-state value, and a steady-state phase during which the amplitude is maintained at the steady-state value.

20. The method of claim 19, wherein the amplitude is exponentially decreased from the initial value to the steady-state value during the amplitude adjustment phase.

21. The method of claim 19, wherein the amplitude is linearly decreased from the initial value to the steady-state value during the amplitude adjustment phase.

22. The method of claim 16, wherein the frequency of the conveyed electrical energy is greater than 2 KHz during the initial phase.

23. The method of claim 16, wherein the frequency of the conveyed electrical energy is in the range of 3 KHz-20 KHz during the initial phase.

24. The method of claim 16, wherein the time-varying electrical energy is sinusoidal.

25. The method of claim 16, wherein the initial phase is in the range of 0.1-20 ms.

26. The method of claim 16, wherein the subsequent phase is greater than the initial phase.

27. The method of claim 16, wherein the frequency of the conveyed electrical energy during the subsequent phase is a decreased frequency.

28. The method of claim 16, further comprising applying stimulation pulses to a stimulation site during the initial phase and the subsequent phase to evoke the action potentials at the stimulation site, wherein the stimulation site is proximal to the blocking site.