System and method for assessing neural health

• US 9,301,711 B2
• Filed: 11/12/2013
• Issued: 04/05/2016
• Est. Priority Date: 11/10/2011
• Status: Active Grant

• Current Assignee: Innovative Surgical Solutions, LLC (Johnson & Johnson)
• Original Assignee: Innovative Surgical Solutions, LLC (Johnson & Johnson)
• Inventors: Bartol, Stephen, Wybo, Christopher
• Primary Examiner(s): HENSON, DEVIN B
• Application Number:
  US14/077,272
• Publication Number:
  US 20140073986A1
• Time in Patent Office: 875 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2505/05 Surgical care
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/1104 induced by stimuli or drugs; A61B5/1102 takes precedence; investigating medicinal preparations G01N33/15
• CPC Class Codes: A61B 5/1107 Measuring contraction of parts of the body, e.g. organ, muscle apparatus for measuring work or force in general G01L
• CPC Class Codes: A61B 5/4029 for evaluating the peripheral nervous systems A61B5/24 takes precedence
• CPC Class Codes: A61B 5/4041 Evaluating nerves condition
• CPC Class Codes: A61B 5/4519 Muscles A61B5/389, A61B5/224 take precedence
• CPC Class Codes: A61B 5/4893 Nerves
• CPC Class Codes: A61B 5/6828 Leg
• CPC Class Codes: A61N 1/0551 Spinal or peripheral nerve electrodes

Abstract

A method of identifying a change in the health of a nerve during a surgical procedure includes determining a sensitivity of the nerve at a first time, determining a sensitivity of the nerve at a second time, and providing an indication to a user corresponding to a change in the sensitivity of the nerve from the first time to the second time. In each instance, the sensitivity of the nerve is determined by providing an electrical stimulus via an electrode disposed on a distal end portion of an elongate medical instrument, and monitoring a magnitude of a mechanical response of a muscle innervated by the nerve.

Claims

1. A method of identifying a change in the health of a nerve during a surgical procedure, wherein the nerve extends within an intracorporeal treatment area of a subject and innervates a muscle of the subject, the method comprising:

determining a sensitivity of the nerve via Mechanomyography periodically throughout the surgical procedure;

providing an indication to a user corresponding to a difference in nerve sensitivity between a first time during the procedure and a second time during the procedure; and

wherein the difference in nerve sensitivity corresponds to the change in the health of a nerve; and

wherein determining the sensitivity of the nerve includes;

providing an electrical stimulus via an electrode disposed on a distal end portion of an elongate medical instrument, the elongate medical instrument being configured to extend within the intracorporeal treatment area; and

receiving a mechanomyography output signal generated by a non-invasive mechanical sensor disposed in mechanical communication with the muscle of the subject, the mechanomyography output signal corresponding to a mechanical movement of the muscle that is induced by the electrical stimulus.

2. The method of claim 1, wherein determining a sensitivity of the nerve further includes:

determining the minimum electrical stimulus that must be provided to the nerve to artificially induce a mechanical response of the muscle; and

wherein the minimum electrical stimulus is indicative of the sensitivity of the nerve.

3. The method of claim 1, wherein determining a sensitivity of the nerve at both the first time and at the second time further includes:

determining a peak amplitude of the mechanomyography output signal; and

wherein the peak amplitude is indicative of the sensitivity of the nerve.

4. A method of identifying a change in the health of a nerve during a surgical procedure, wherein the nerve extends within an intracorporeal treatment area of a subject and innervates a muscle of the subject, the method comprising:

determining a sensitivity of the nerve periodically throughout the surgical procedure by;

providing an electrical stimulus via an electrode disposed on a distal end portion of an elongate medical instrument configured to extend within the intracorporeal treatment area;

monitoring a magnitude of a mechanical response of the muscle, wherein the mechanical response of the muscle is artificially induced by the electrical stimulus;

providing an indication to a user corresponding to a difference between the magnitude of the mechanical response at a first time during the surgical procedure and the magnitude of the mechanical response at a second time during the surgical procedure, and wherein the difference is indicative of a change in the health of the nerve; and

wherein monitoring the magnitude of the mechanical response includes receiving a mechanomyography output signal generated by a non-invasive mechanical sensor disposed in mechanical communication with the muscle, the mechanomyography output signal corresponding to a mechanical movement of the muscle that is induced by the electrical stimulus.

5. The method of claim 4, wherein providing an indication to a user includes displaying, via a display device, the magnitude of the second mechanical response as a percentage of the magnitude of the first mechanical response.

6. The method of claim 5, further comprising providing an indication to a user corresponding to the difference between the magnitude of the second mechanical response and a predefined threshold.

7. The method of claim 4, further comprising, retracting tissue within the intracorporeal treatment area of a subject between the first time and the second time.

8. The method of claim 7, wherein the tissue includes a portion of a psoas muscle of the subject.

9. The method of claim 7, wherein the elongate medical instrument is a retractor blade used to retract the tissue within the intracorporeal treatment area of a subject.

10. The method of claim 4, wherein the electrical stimulus is provided at a common current at both the first time and the second time.

11. The method of claim 4, wherein providing the electrical stimulus via the electrode includes transmitting an electrical current from the electrode to tissue of the subject within the intracorporeal treatment region.

12. The method of claim 4, wherein the first time and the second time are from about 2 seconds apart to about 60 seconds apart.

13. The method of claim 4, further comprising:

revising the indication provided to the user to correspond to a difference between the magnitude of the mechanical response at a third time and the magnitude of the mechanical response at the first time, and wherein the difference is indicative of a change in the health of the nerve from the first time to the third time.