System and method for selective and maintained activation of sensory peripheral nerve fibers

Patent metadata

Field	Value
Publication number	US-9636497-B2
Application number	US-201615180613-A
Country	US
Kind code	B2
Filing date	Jun 13, 2016
Priority date	Jul 2, 2013
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

Electrical stimulation is applied to a patient at least in part via a pulse generator. A motor fiber component of an action potential that is evoked in response to the electrical stimulation is measured. A sensory fiber component of the action potential is also measured. A relationship between the motor fiber component and the sensory fiber component is determined. For example, a ratio between the sensory fiber component and the motor fiber component may be calculated, or the absolute sizes of the sensory fiber component and the motor fiber component may be compared. Based on the determined relationship between the motor and sensory fiber components, a paresthesia of the patient is estimated.

First claim

What is claimed is:

1. A method, comprising:
applying electrical stimulation to a patient at least in part via a pulse generator;
measuring a motor fiber component of an action potential that is evoked in response to the electrical stimulation;
measuring a sensory fiber component of the action potential; and
determining a relationship between the motor fiber component and the sensory fiber component.

2. The method of claim 1 , further comprising: estimating a paresthesia of the patient based on the determining.

3. The method of claim 1 , wherein the determining comprises: calculating a ratio between the sensory fiber component and the motor fiber component.

4. The method of claim 1 , wherein the determining comprises: comparing absolute sizes of the sensory fiber component and the motor fiber component.

5. The method of claim 1 , further comprising:
repeating the applying of the electrical stimulation, the measuring of the motor fiber component, the measuring of the sensory fiber component, and the determining the relationship between the motor fiber component and the sensory fiber component a plurality of times, wherein a different set of stimulation parameters is used for each of the times; and
selecting one or more of the sets of stimulation parameters as optimized sets of stimulation parameters based on the determined relationship between the motor fiber component and the sensory fiber component for each of the times.

6. The method of claim 1 , wherein:
the measuring of the motor fiber component is performed within a first time window; and
the measuring of the sensory fiber component is performed within a second time window that occurs after the first time window.

7. The method of claim 1 , wherein the applying of the electrical stimulation, the measuring of the motor fiber component, the measuring of the sensory fiber component, and the determining the relationship between the motor fiber component and the sensory fiber component are performed when the patient is in actual surgery.

8. The method of claim 1 , wherein the applying of the electrical stimulation, the measuring of the motor fiber component, the measuring of the sensory fiber component, and the determining the relationship between the motor fiber component and the sensory fiber component are performed in an automated manner without requiring a voluntary feedback from the patient.

9. A medical system, comprising:
a pulse generator configured to apply electrical stimulation to a patient;
a measurement tool configured to measure a motor fiber component and a sensory fiber component of an action potential that is evoked from in response to the electrical stimulation; and
an electronic processor configured to determine a relationship between the motor fiber component and the sensory fiber component.

10. The medical system of claim 9 , wherein the electronic processor is further configured to estimate a paresthesia of the patient based on the determined relationship between the motor fiber component and the sensory fiber component.

11. The medical system of claim 9 , wherein the electronic processor is further configured to calculate a ratio between the sensory fiber component and the motor fiber component.

12. The medical system of claim 9 , wherein:
the pulse generator is configured to apply a plurality of cycles of electrical stimulation, wherein a different set of stimulation parameters is used in each cycle;
the measurement tool is configured to measure the motor fiber component and the sensory fiber component corresponding to each cycle; and
the electronic processor is configured to determine the relationship between the motor fiber component and the sensory fiber component corresponding to each cycle.

13. The medical system of claim 12 , wherein the electronic processor is configured to select one or more of the sets of stimulation parameters as optimized sets of stimulation parameters based on the determined relationship between the motor fiber component and the sensory fiber component corresponding to each cycle.

14. The medical system of claim 9 , wherein:
the measurement tool is configured to measure the motor fiber component within a first time window; and
the measurement tool is configured to measure the sensory fiber component within a second time window that occurs after the first time window.

15. A medical device, comprising:
stimulation circuitry configured to apply electrical stimulation to a patient;
measurement circuitry configured to measure a motor fiber component and a sensory fiber component of an action potential that is evoked from in response to the electrical stimulation; and
controller circuitry configured to determine a relationship between the motor fiber component and the sensory fiber component.

16. The medical device of claim 15 , wherein the controller circuitry is further configured to estimate a paresthesia of the patient based on the determined relationship between the motor fiber component and the sensory fiber component.

17. The medical device of claim 15 , wherein the controller circuitry is further configured to calculate a ratio between the sensory fiber component and the motor fiber component.

18. The medical device of claim 15 , wherein:
the stimulation circuitry is configured to apply a plurality of cycles of electrical stimulation, wherein a different set of stimulation parameters is used in each cycle;
the measurement circuitry is configured to measure the motor fiber component and the sensory fiber component corresponding to each cycle; and
the controller circuitry is configured to determine the relationship between the motor fiber component and the sensory fiber component corresponding to each cycle.

19. The medical device of claim 18 , wherein the controller circuitry is configured to select one or more of the sets of stimulation parameters as optimized sets of stimulation parameters based on the determined relationship between the motor fiber component and the sensory fiber component corresponding to each cycle.

20. The medical device of claim 15 , wherein:
the measurement circuitry is configured to measure the motor fiber component within a first time window; and
the measurement circuitry is configured to measure the sensory fiber component within a second time window that occurs after the first time window.

Assignees

• Greatbatch Ltd

Inventors

• Bradley Kerry
• Halberg Leslie

Classifications

• A61B8/0841

  for locating instruments · CPC title

• A61N1/36153

  Voltage (A61N1/3616 takes precedence) · CPC title

• A61N1/36146

  specified by the stimulation parameters · CPC title

• A61N1/0553

  Paddle shaped electrodes, e.g. for laminotomy · CPC title

• A61B5/064

  using markers (A61B5/062 takes precedence) · CPC title