Compensation reduction in tissue stimulation therapy

• US 20070255374A1
• Filed: 04/28/2006
• Published: 11/01/2007
• Est. Priority Date: 04/28/2006
• Status: Active Grant

• Current Assignee: LivaNova USA, Inc. (LivaNova Plc)
• Original Assignee: Cyberonics, Inc
• Inventors: Maschino, Steven, Kolafa, Jerry
• Granted Patent: US 7,962,220 B2
• Time in Patent Office: Days
• US Class Current: 607/118
• CPC Class Codes: A61N 1/36082 Cognitive or psychiatric applications, e.g. dementia or Alzheimer's disease

Abstract

Methods and systems for reducing compensation of the body to therapy delivered by an implanted medical device are described herein. The disclosed techniques cause a change from one therapy protocol to another therapy protocol based on the occurrence of an event (e.g., time, user activations of a sensor, input from a physiological sensor, etc.). The therapy protocols of the implanted medical device differ in terms of the on-time and off-time, but effectuate the same or similar duty cycle.

Claims

1. A method of treating a patient, comprising:

delivering an electrical signal to a nerve according to a first setting of an on-time and off-time that defines a duty cycle; and

automatically changing said first setting to a second setting of on-time and off-time in response to a first event, wherein said second setting defines a duty cycle substantially equal to the duty cycle defined by said first setting.

2. The method of claim 1, wherein (b) further comprises sensing an occurrence of said first event following changing to said second setting and repeating (a) and (b).

3. The method of claim 1 wherein said first event comprises an expiration of a defined time period.

4. The method of claim 1, wherein said first event comprises a physiological or psychological event.

5. The method of claim 1, wherein said first event comprises a sensed user input.

6. The method of claim 1, further comprising automatically changing said second setting to a third setting of on-time and off-time in response to a second event, wherein said third setting defines a duty cycle substantially equal to the duty cycle defined by said first and second settings.

7. A system, comprising:

at least one electrode coupled to a nerve;

a pulse generator coupled to said at least one electrode, wherein said pulse generator provides an electrical signal to a nerve using said at least one electrode; and

a controller coupled to said pulse generator, wherein said controller causes said pulse generator to deliver said electrical signal to a nerve according to a first setting of an on-time and off-time that defines a first duty cycle and, in response to a first event, causes a change from said first setting to a second setting of an on-time and off-time that defines a second duty cycle that is substantially equal to the first duty cycle.

8. The system of claim 7, further comprising a user input sensor coupled to the controller, wherein said user input sensor senses a manual control input to control an operation of the pulse generator.

9. The system of claim 8, wherein said first event comprises a user activation parameter of said sensor in excess of an activation parameter threshold.

10. The system of claim 7, further comprising a physiological sensor coupled to the controller to control, at least in part, changing from the first setting to the second setting.

11. The system of claim 7 wherein said first event comprises an expiration of a defined time period.

12. The system of claim 11 further comprising a user input sensor capable of sensing a user input signal, and wherein said first event comprises at least one of an expiration of a defined time period and a sensed user input signal.

13. A method of treating a patient having a medical condition, comprising:

applying to a vagus nerve of the patient a first electrical signal defined by a first plurality of parameters comprising a first on-time and a first off-time defining a first duty cycle;

determining the occurrence of a first event and, in response to said first event

ceasing said step of applying said first electrical signal to said vagus nerve, and

applying to said vagus nerve a second electrical signal defined by a second plurality of parameters comprising a second on-time and a second off-time defining a second duty cycle substantially the same as said first duty cycle.

14. The method of claim 13 wherein said first plurality of parameters comprises at least one of a first current magnitude, a first frequency, and a first pulse width, and said second plurality of parameters comprises at least one of a second current magnitude, a second frequency, and a second pulse width.

15. The method of claim 14 wherein at least one of said second current magnitude, said second frequency, and said second pulse width is the same as a respective one of said first current magnitude, said first frequency, and said first pulse width.

16. The method of claim 13 wherein said first event first is selected from the group consisting of the expiration of a defined time period, a physiological event, a psychological event, and a sensed user input.

17. The method of claim 13 further comprising:

detecting the occurrence of a second event, and in response to said second event

ceasing said step of applying said second electrical signal to said vagus nerve, and

applying said first electrical signal to said vagus nerve.

18. The method of claim 13 further comprising:

detecting the occurrence of a second event, and in response to said second event

ceasing said step of applying said second electrical signal to said vagus nerve, and

applying to said vagus nerve a third electrical signal defined by a third plurality of parameters comprising a third on-time and a third off-time characterized by a third duty cycle substantially the same as said first duty cycle.

19. The method of claim 13, wherein said second duty cycle differs from said first duty cycle by no more than 25%

20. The method of claim 13, wherein said second duty cycle differs from said first duty cycle by no more than 10%.

21. The method of claim 13, wherein said second duty cycle differs from said first duty cycle by no more than 5%.