Optimizing stimulation therapy of an external stimulating device based on firing of action potential in target nerve

• US 7,970,478 B2
• Filed: 12/19/2008
• Issued: 06/28/2011
• Est. Priority Date: 12/19/2008
• Status: Active Grant

• Current Assignee: Ethicon Incorporated (Johnson & Johnson)
• Original Assignee: Ethicon Incorporated (Johnson & Johnson)
• Inventors: Wahlgren, Stephen, Tracey, Michael R.
• Primary Examiner(s): Manuel; George
• Assistant Examiner(s): Wieland; Robert N
• Application Number:
  US12/317,194
• Publication Number:
  US 20100161005A1
• Time in Patent Office: 921 Days
• Field of Search: 600/300, 600/372, 600/544, 607/2, 607/46, 607/57, 607/61, 607/62, 607/48, 607/544
• US Class Current: 607/62
• CPC Class Codes: A61B 2560/0276 Determining malfunction
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
• CPC Class Codes: A61B 5/242 Detecting biomagnetic fields, e.g. magnetic fields produced by bioelectric currents
• CPC Class Codes: A61B 5/4041 Evaluating nerves condition
• CPC Class Codes: A61B 5/6846 specially adapted to be brought in contact with an internal body part, i.e. invasive
• CPC Class Codes: A61N 1/36017 with leads or electrodes penetrating the skin
• CPC Class Codes: A61N 1/3603 Control systems

Abstract

A method and system for optimizing stimulation therapy of an external stimulating device. The stimulating signal for stimulation of a target nerve is produced using the external stimulating device. A magnetic field is induced in an implanted transmitting coil disposed proximate the target nerve when the action potential is fired along an axon of the target nerve. In turn, a feedback signal is generated in a receiving coil associated with the external stimulating device based on whether the target nerve fires an action potential. Stimulating signal parameters of the stimulating signal are adjusted based on the feedback signal.

Claims

1. A method for optimizing stimulation therapy for an external stimulating device, comprising the steps of:

generating a stimulating signal for stimulation of a target nerve using the external stimulating device;

producing a feedback signal based on whether the target nerve fires an action potential; and

adjusting a stimulating signal parameter of the stimulating signal based on the feedback signal;

wherein the producing step comprises the step of generating a magnetic field induced in an implanted transmitting coil disposed proximate the target nerve when the action potential fires along an axon along the target nerve in response to the generated stimulating signal produced by the external stimulating device;

grid the feedback signal is produced in a receiving coil associated with the external stimulating device based on the generated magnetic field induced in the implanted transmitting coil.

2. The method in accordance with claim 1, wherein the implanted transmitting coil serves a dual function of monitoring the firing of the action potential along the axon of the target nerve and inducing the feedback signal in the receiving coil of the external stimulating device.

3. The method in accordance with claim 1, wherein the producing step further comprises the step of processing and amplifying the feedback signal in the receiving coil using signal conditioning and amplification circuitry.

4. The method in accordance with claim 1, wherein the adjustment of the stimulating signal parameter is performed by a processor.

5. The method in accordance with claim 1, wherein the stimulating signal parameter is one of amplitude, frequency or a waveform itself.

6. The method in accordance with, claim 1, wherein the adjusting step comprises, when the feedback signal is zero, indicating that the target nerve was not stimulated nor was the action potential fired, adjusting the stimulating signal parameter;

whereas when the feedback signal is greater than zero indicating that the target nerve was stimulated and the action potential was fired, no adjustment is made to the stimulating signal parameter.

7. The method in accordance with claim 1, wherein adjustment of the stimulating signal parameter is in predetermined increments.

8. The method in accordance with claim 7, wherein adjustment of the stimulating signal parameter is in increments of approximately 0.5 V.

9. The method in accordance with claim 6, wherein the adjusting step further comprises, at least one of activating an alarm and shutting off the external stimulating device, if the adjusted stimulating signal parameter exceeds a predetermined maximum threshold allowed without detecting the firing of the action potential in the target nerve.

10. A system for optimizing stimulation therapy, comprising:

a transmitting coil implantable proximate a target nerve, the transmitting coil generating a magnetic field induced therein when an action potential fires along an axon along a target nerve;

an external stimulating device for generating a stimulating signal for stimulation of the target nerve;

the external stimulating device comprising;

a receiving coil for producing a feedback signal based on the generated magnetic field induced in the transmitting coil; and

a processor for adjusting a stimulating signal parameter of the stimulating signal based on the feedback signal.

11. The system in accordance with claim 10, further comprising signal conditioning and amplification circuitry for reducing noise and amplifying the feedback signal.

12. The system in accordance with claim 10, wherein the stimulating signal parameter is one of amplitude, frequency or a waveform itself.

13. The system in accordance with claim 10, wherein the processor is programmed so that when the feedback signal is zero indicating that the target nerve was not stimulated nor was the action potential fired, the stimulating signal parameter is adjusted;

whereas when the feedback signal is greater than zero indicating that the target nerve was stimulated and the action potential was fired, no adjustment is made to the stimulating signal parameter.

14. The system in accordance with claim 10, wherein adjustment of the stimulating signal parameter is in predetermined increments.

15. The system in accordance with claim 14, wherein adjustment of the stimulating signal parameter is in increments of approximately 0.5 V.

16. The system in accordance with claim 13, further comprising an alarm adapted to be activated if the adjusted stimulating signal parameter exceeds a predetermined maximum threshold allowed without detecting the firing of the action potential in the target nerve.

17. The system in accordance with claim 13, wherein the external stimulating device is shut off, if the adjusted stimulating signal parameter exceeds a predetermined maximum threshold allowed without detecting the firing of the action potential in the target nerve.

18. The system in accordance with claim 10, wherein the implantable transmitting coil serves a dual function of monitoring the firing of the action potential along the axon of the target nerve and inducing the feedback signal in the receiving coil of the external stimulating device.