Sensing Nerve Regeneration with Implantable Flexible Electronics

Abstract

Objectives:

(1) Translate epidermal electronic systems (EES) into an implantable electrode system (IES) with the potential to detect electric activity from growing axons distal to the site of nerve repair. (2) Demonstrate baseline and stimulated activity in intact nerves using IES. (3) Demonstrate nerve activity using IES following nerve regeneration across a surgical repair site.

Methods:

EES consists of thin flexible electronic circuitry that is capable of sensing and wirelessly transmitting multiple modalities including electrical activity, temperature, and stretch following transfer to skin. We have modified EES technology into an implantable electrode system consisting of biocompatible components that can detect nerve activity in vivo in a rodent model. We obtained recordings of intact sciatic nerve activity following pulsed stimulation applied via the proximal portion of the electrode array. Future experiments will focus on detection of activity following nerve transection and repair.

Results:

A first-generation IES sensor was tested on intact mouse sciatic nerves. Proximal electrodes were used to stimulate the nerve, and distal electrodes recorded the stimulus. Action potentials were successfully recorded. Recorded activity was abolished following nerve transection.

Conclusions:

We demonstrate the adaptation of EES technology with the ability to stimulate and record nerve activity in a rodent model. An implantable device capable of sensing nerve regeneration would provide crucial information on the status of nerve repair and at much earlier time points allowed by clinical exam and electromyography. This technology has the potential to improve clinical decision-making and patient outcomes.