Threshold optimization for tissue stimulation therapy

• US 20070255351A1
• 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: Begnaud, Jason, Nguyen, Huan, Dupont, Chris, Kolafa, Jerry
• Granted Patent: US 7,869,885 B2
• Time in Patent Office: Days
• US Class Current: 607/62
• CPC Class Codes: A61N 1/36139 with automatic adjustment

Abstract

Methods and systems for determining an optimal therapeutic window of parameter settings for nerve stimulation therapy are described herein. The disclosed techniques generally utilize one or more parameter sweeps to determine upper and lower threshold settings. The determination of the optimal therapeutic window may be performed during or after implantation.

Claims

1. A method, comprising:

a) delivering an electrical signal to a cranial nerve of a patient according to at least a first parameter and a second parameter;

b) measuring an electrical response of said nerve to said electrical signal;

c) adjusting said first parameter while said second parameter remains constant; and

d) repeating a) through c) to acquire a plurality of electrical responses; and

e) determining a lower threshold setting and an upper threshold setting from the plurality of electrical responses.

2. The method of claim 1, wherein said lower threshold setting corresponds to a minimum electrical signal level necessary to evoke a compound action potential response on said nerve.

3. The method of claim 1, wherein said upper threshold setting corresponds to an electrical signal level above which increasing said first parameter does not cause an increase in said electrical response or an increase in said electrical response greater than a specified amount.

4. The method of claim 1, further comprising, prior to (a), defining an initial first and second parameter setting, wherein said initial first and second parameter setting does not define an electrical signal that evokes a compound action potential response.

5. The method of claim 1, wherein said first parameter comprises a parameter selected from the group consisting of current amplitude, frequency, pulse width, on-off time, and duty cycle.

6. The method of claim 1, further comprising adjusting said second parameter and repeating (a) through (d).

7. The method of claim 1, wherein (a) through (e) are performed automatically.

8. The method of claim 1, wherein (a) through (d) are performed during implantation of an implantable medical device into the body of the patient.

9. The method of claim 1, wherein (b) further comprises measuring an electrical response of said nerve to a trigger signal received from an electrical signal generator, said trigger signal indicating an occurrence of said electrical signal.

10. The method of claim 1, wherein (a) through (e) are performed after implantation of an implantable medical device into the body of the patient.

11. The method of claim 1, further comprising attaching a temporary electrode to said nerve to measure said electrical response.

12. A method, comprising:

a) delivering a plurality of electrical signals to a nerve of a patient at a plurality of current amplitudes and a constant pulse width;

b) recording a plurality of electrical responses of the nerve to the plurality of electrical signals; and

c) determining at least one lower threshold setting and at least one upper threshold setting from the plurality of electrical responses.

13. The method of claim 12, further comprising adjusting said pulse width and repeating (a) through (c).

14. The method of claim 12, further comprising defining a range for the plurality of current amplitudes prior to (a).

15. The method of claim 12, wherein said recording a plurality of electrical responses further comprises storing said plurality of electrical responses, said plurality of current amplitudes, and said pulse width on a storage medium.

16. The method of claim 12, wherein (a) through (c) are performed automatically.

17. The method of claim 12, wherein determining a lower threshold setting comprises determining a current amplitude and a pulse width that corresponds to a minimum electrical signal level necessary to evoke a compound action potential.

18. The method of claim 12, wherein determining an upper threshold setting comprises determining a current amplitude and a pulse width corresponding to an electrical signal level where increasing said current amplitude does not cause an increase in the electrical response or an increase in the electrical response greater than a specified amount.

19. The method of claim 12, wherein (b) further comprises recording an electrical response of the nerve in response to a trigger signal received from an electrical signal generator, said trigger signal indicating an occurrence of an electrical signal.

20. A system, comprising:

a processor;

software executable on said processor, wherein said software causes the processor to;

a) instruct an implantable medical device to deliver a plurality of electrical signals to a nerve according to at least first and second parameters, wherein said first parameter is iteratively adjusted while said second parameter remains fixed,

b) detect a plurality of electrical responses of the nerve to said plurality of electrical signals, and

c) determine a lower threshold setting and an upper threshold setting from said plurality of electrical responses based on said fixed second parameter.

21. The system of claim 20, wherein said software executable on said processor further causes the processor to adjust said second parameter and repeat (a) through (c).

22. The system of claim 21, wherein said software executable on said processor further causes the processor to determine a plurality of lower threshold settings and a plurality of upper threshold settings, wherein each lower threshold setting and each upper threshold setting corresponds to a different second parameter setting.

23. The system of claim 20, further comprising a programming device for programming said plurality of electrical signals and a removable cuff assembly comprising at least one sensing electrode, wherein said removable cuff assembly is coupled to said programming device.

24. The system of claim 20, wherein (b) comprises detecting an electrical response of said nerve to a trigger signal received from said implantable medical device, said trigger signal indicating an occurrence of an electrical signal.