Waveform shapes for treating neurological disorders optimized for energy efficiency

• US 9,089,708 B2
• Filed: 05/27/2011
• Issued: 07/28/2015
• Est. Priority Date: 05/27/2010
• Status: Active Grant

• Current Assignee: NDI Medical, LLC
• Original Assignee: NDI Medical, LLC
• Inventors: Grill, Warren M., Wongsarnpigoon, Amorn
• Primary Examiner(s): Schaetzle, Kennedy
• Application Number:
  US13/118,081
• Publication Number:
  US 20120136408A1
• Time in Patent Office: 1,523 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: A61N 1/0529 Electrodes for brain stimulation
• CPC Class Codes: A61N 1/3606 adapted for a particular treatment
• CPC Class Codes: A61N 1/36146 specified by the stimulation parameters
• CPC Class Codes: A61N 1/36175 Pulse width or duty cycle

Abstract

Systems and methods for stimulation of neurological tissue apply a stimulation waveform that is derived by a developed genetic algorithm (GA), which may be coupled to a computational model of extracellular stimulation of a mammalian myelinated axon. The waveform is optimized for energy efficiency.

Claims

1. A system for neurological tissue stimulation comprising

a lead sized and configured for implantation in a targeted tissue stimulation region,

a pulse generator coupled to the lead, the pulse generator including a power source comprising a battery and a microprocessor coupled to the battery and being operable to apply to the lead a stimulation waveform derived at least in part through the use of a global optimization algorithm, and

wherein the microprocessor controls a generation of the stimulation waveform through a software implementation of a function comprising:

2. A system according to claim 1, wherein the stimulation waveform is derived through the use of a prescribed genetic algorithm (GA) coupled to a computational model of extracellular stimulation of a mammalian myelinated axon, wherein the waveform is optimized for energy efficiency to prolong battery life.

3. A system according to claim 1

wherein the waveform consists essentially of a Gaussian curve.

4. A system according to claim 1

wherein the waveform consists essentially of a truncated Gaussian curve.

5. A system according to claim 1

wherein the waveform is monophasic.

6. A system according to claim 1

wherein the waveform is biphasic.

7. A system according to claim 1

wherein the pulse generator is implantable.

8. A system according to claim 1, wherein A, β

, α

_L, α

_R, β

_L, and β

_R are selectively programmable.

9. A system according to claim 1, wherein A is within a range of about 10 microamps to about 10 milliamps.

10. A system according to claim 9, wherein α

_L and α

_R are greater than zero milliseconds and less than infinity milliseconds.

11. A system according to claim 1, wherein α

_L and α

_R are within a range of about 0.008 milliseconds to about 0.1 milliseconds.

12. A system according to claim 11, wherein β

_L and β

_R are greater than zero and less than infinity.

13. A system according to claim 12, wherein β

_L and β

_R are within a range of about 0.8 to about 1.8.

14. A system for creating a stimulation waveform optimized for energy efficiency comprising a population of parent stimulation waveforms, first means including a genetic algorithm (GA) for generating a population of offspring stimulation waveforms by mating the population of parent stimulation waveforms,

second means consisting essentially of a computational model of extracellular stimulation of a mammalian myelinated axon, being operative for assessing the fitness of individual offspring stimulation waveforms generated by the first means in terms of energy efficiency and selecting as a new population of parent stimulation waveforms the current offspring stimulation waveforms having the highest energy efficiency values, the selection terminating when predetermined termination criteria is met.

15. A system according to claim 14

wherein the termination criteria includes the fitness of successive populations of offspring stimulation waveforms converging toward a common energy-efficiency value.

16. A system according claim 14

wherein the stimulation waveform optimized for energy efficiency consists essentially of a Gaussian curve.

17. A system according claim 14

wherein the stimulation waveform optimized for energy efficiency consists essentially of a truncated Gaussian curve.