Patent ID: 8562539
Filing Date: 2013-10-22
Classification: A61B

Abstract:
1. A method of determining at least one of a change in nerve status and a change in nerve proximity, comprising the steps of: (a) applying a first stimulus signal to a stimulus electrode communicatively linked to a controller that directs application of electrical stimulus signals, said stimulus electrode being situated on a medical device and located a distance from a nerve; (b) detecting with a sensor communicatively linked to said controller an EMG response generated by a muscle physiologically coupled to said nerve in response to said first stimulus signal; (c) increasing said first stimulus signal and repeating steps (a) and (b) until said controller determines said detected EMG response associated with said nerve reaches a predetermined minimum EMG value representing an evoked muscle action potential; (d) identifying the level of said first stimulus signal required to obtain said predetermined minimum EMG value; (e) storing in a non-transitory fashion on the controller the identified level of said first stimulus signal required to obtain said predetermined minimum EMG value; (f) repeating steps (a) through (d) with a second stimulus signal to identify the level of said second stimulus signal required to obtain said predetermined minimum EMG value associated with said nerve; and (g) recalling on the controller the identified level of said first stimulus signal level and determining at least one of a change in nerve status and a change in nerve proximity based on a comparison of said first stimulus signal level required to obtain said predetermined minimum EMG value and said second stimulus signal level required to obtain said predetermined minimum EMG value.