Neuromodulation device and method for use
Neuromodulation devices and methods of their use are described in which a therapeutic device is configured to generate a treatment for treating pain such as the reduction of the symptoms of chronic and acute pain as well as for treating other conditions. The neuromodulation device generates an output electrical signal in the form of pulses with a fast rise-time spike waveform followed by a longer-duration, lower amplitude primary phase waveform. The output signal includes a broad range of frequency components, with time constants tuned so as to interact with specific cell membrane or cellular components. The output signal may be conducted to the patient via electrodes. The pulses are triggered at variable intervals which prevent habituation.
1. A neuromodulation treatment apparatus, comprising:
a controller programmed to transmit one or more pulse waveforms having a spike and a primary phase following the spike,
wherein the spike has a first amplitude of up to 100 V and which is independent of an effect of variations in load impedance and a first duration time of between 1-5 μs and the primary phase has a second amplitude which is also independent of the effect of variations in load impedance and a second duration time,
wherein the first amplitude is greater than the second amplitude and the first duration time is less than the second duration time such that the spike has an intensity which is greater than an average intensity of the primary phase, and
wherein an electric field of the spike has a strength sufficient to produce a conformational change in cellular components of a tissue region of interest and an electric field of the primary phase has a strength sufficient to maintain the conformational change induced by the electric field of the spike.
2. The apparatus of claim 1 wherein the spike has a total energy per pulse of 55 μJ.
3. The apparatus of claim 1 wherein the one or more pulse waveforms are applied over an inter-electrode distance of between 5-20 cm such that a sub-threshold value is 0.01e-3 V-s/m.
4. The apparatus of claim 1 wherein the one or more pulse waveforms are applied over an inter-electrode distance of 1 cm such that a sub-threshold value is 0.1e-3 V-s/m.
5. The apparatus of claim 1 wherein the spike has a rise time of less than 1 μs.
6. The apparatus of claim 1 wherein the spike has a rise time of less than 50 ns.
7. The apparatus of claim 1 wherein the spike has a rise time of less than 100 ns.
8. The apparatus of claim 1 wherein the spike has a rise time of less than 500 ns.
9. The apparatus of claim 1 wherein the spike has a rise time of between 100 and 300 ns.
10. The apparatus of claim 1 wherein the spike and the primary phase have the same polarity.
11. The apparatus of claim 1 wherein the primary phase has an average current of between 1 and 100 mA.
12. The apparatus of claim 1 wherein the primary phase has an average current of between 10 and 50 mA.
13. The apparatus of claim 1 wherein the primary phase has a duration time of between 20 and 500 μs.
14. The apparatus of claim 1 wherein the primary phase has a duration time of between 80 and 120 μs.
15. The apparatus of claim 1 wherein the controller is further programmed to transmit a dead time having a zero amplitude following the primary phase.
16. The apparatus of claim 1 wherein the controller is further programmed to transmit a secondary phase following the primary phase, wherein the secondary phase has a polarity opposite to a polarity of the primary phase to allow for a controlled discharge of a tissue region of interest.
17. The apparatus of claim 16 wherein the secondary phase has a net charge per pulse of less than 10% of a total charge during the primary phase.
18. The apparatus of claim 16 wherein the secondary phase has a residual voltage at an end of the secondary phase of less than 10% of a peak voltage during the primary phase.
19. The apparatus of claim 16 wherein the secondary phase has a third duration time of 3-5 times the second duration time.
20. The apparatus of claim 16 wherein the spike has a rise time of between 10-500 ns, the second duration time of between 50-500 μs, and a third duration time of the secondary phase of between 50-2000 μs.
21. The apparatus of claim 20 further comprising a dead time duration of between 0-100 μs between the primary phase and the secondary phase.
22. The apparatus of claim 16 wherein the spike has a rise time of between 200-300 ns, the second duration time of between 80-120 μs, and a third duration time of the secondary phase of between 80-480 μs.
23. The apparatus of claim 22 further comprising a dead time duration of between 20-60 μs between the primary phase and the secondary phase.
24. The apparatus of claim 16 wherein the spike has a rise time of 300 ns, the first duration time of 4.6 μs, the second duration time of 90 μs, and a third duration time of the secondary phase of 360 μs.
25. The apparatus of claim 24 further comprising a dead time duration of 40 μs between the primary phase and the secondary phase.
26. The apparatus of claim 1 wherein the controller is programmed to transmit a plurality of the pulse waveforms in succession.
27. The apparatus of claim 26 wherein successive pulse waveforms are alternated in direction from one another.
28. The apparatus of claim 26 wherein the plurality of waveforms is comprised of a first group of several pulses having a first polarity followed by a second group with an equal number of pulses having a second polarity opposite to the first polarity.
29. The apparatus of claim 1 wherein the controller is programmed to apply the one or more pulse waveforms to a tissue region between 30 to 90 minutes.
30. The apparatus of claim 1 wherein the controller is programmed to apply the one or more pulse waveforms to a tissue region for at least 15 minutes.
31. The apparatus of claim 1 further comprising a first electrode and a second electrode in electrical communication with the controller for transmitting the one or more pulse waveforms.
32. The apparatus of claim 30 wherein a peak voltage of the spike divided by a spacing between the first and second electrodes is at least 8 V/cm.
33. The apparatus of claim 30 wherein a peak voltage of the spike divided by a spacing between the first and second electrodes is at least 50 V/cm.
34. The apparatus of claim 30 wherein a peak voltage of the spike divided by a spacing between the first and second electrodes is at least 100 V/cm.
35. The apparatus of claim 30 wherein the first and second electrodes each have a contact area of 5 to 100 cm 2 .
36. The apparatus of claim 30 wherein the first and second electrodes each have a contact area of 25 to 50 cm 2 .
37. The apparatus of claim 1 wherein a peak current of the spike is at least 30 mA.
38. The apparatus of claim 1 wherein a peak current of the spike is at least 80 mA.
39. The apparatus in claim 1 wherein an average amplitude of the primary phase is less than 0.5 times a peak amplitude of the spike.
40. The apparatus in claim 1 wherein an average amplitude of the primary phase is less than 0.25 times a peak amplitude of the spike.
41. The apparatus of claim 1 wherein the controller is programmed to transmit one or more pulse waveforms having a plurality of spikes near or at a beginning of the primary phase.
42. The apparatus of claim 1 wherein the controller is programmed to transmit one or more pulse waveforms having a plurality of spikes near or at a beginning of the secondary phase.
43. The method of claim 1 wherein the electric field of the spike has a strength sufficient to produce a conformational change when the one or more pulse waveforms are delivered transcutaneously to the tissue region of interest from an external region of a body.