Handcrafted Microwire Regenerative Peripheral Nerve Interfaces with Wireless Neural Recording and Stimulation Capabilities

Ali Ajam,Ridwan Hossain

doi:10.4172/2090-4886.1000133

Abstract

A scalable microwire peripheral nerve interface was developed, which interacted with regenerated peripheral nerves in microchannel scaffolds. Neural interface technologies are envisioned to facilitate direct connections between the nervous system and external technologies such as limb prosthetics or data acquisition systems for further processing. Presented here is an animal study using a handcrafted microwire regenerative peripheral nerve interface, a novel neural interface device for communicating with peripheral nerves. The neural interface studies using animal models are crucial in the evaluation of efficacy and safety of implantable medical devices before their use in clinical studies. 16-electrode microwire microchannel scaffolds were developed for both peripheral nerve regeneration and peripheral nerve interfacing. The microchannels were used for nerve regeneration pathways as a scaffolding material and the embedded microwires were used as a recording electrode to capture neural signals from the regenerated peripheral nerves. Wireless stimulation and recording capabilities were also incorporated to the developed peripheral nerve interface which gave the freedom of the complex experimental setting of wired data acquisition systems and minimized the potential infection of the animals from the wire connections. A commercially available wireless recording system was efficiently adopted to the peripheral nerve interface. The 32-channel wireless recording system covered 16-electrode microwires in the peripheral nerve interface, two cuff electrodes, and two electromyography electrodes. The 2-channel wireless stimulation system was connected to a cuff electrode on the sciatic nerve branch and was used to make evoked signals which went through the regenerated peripheral nerves and were captured by the wireless recording system at a different location. The successful wireless communication was demonstrated in the result section and the future goals of a wireless neural interface for chronic implants and clinical trials were discussed together.

Highlights

Neural interface technologies are envisioned to facilitate direct connections between the nervous system and external technologies such as limb prosthetics or data acquisition systems for further processing
This is a significant advantage of the μPNI because other electrodes that are near each other can create crosstalk due to parasitic capacitances [27]
A biological reaction to foreign materials could be significant in any chronic animal study requiring implantation, especially those that require the implanted device to be kept for more than three months

Summary

Introduction

Neural interface technologies are envisioned to facilitate direct connections between the nervous system and external technologies such as limb prosthetics or data acquisition systems for further processing. Neuronal interface signals captured from awake, freely behaving animals are crucial for the level of clinical applications In amputees, such technologies would provide direct neural control of prosthetic movements and restore sensory feedback by functionally reconnecting damaged efferent motor and afferent sensory pathways. The peripheral nerve has been one target for bidirectional interfacing, with renewed interest generated by reports that peripheral nerve tissue is viable for interfacing even years after injury or amputation [1,2,3,4] Several designs, such as cuff electrodes, flat interface nerve electrodes (FINE) [5,6,7], longitudinal intrafascicular electrodes (LIFE) [5,8,9,10], Utah Slanted Electrode Arrays (USEA) [11,12,13], and regenerative sieve and microchannel electrodes [14,15,16,17,18,19,20] demonstrated selective recording and stimulation. The devices have limited electrode sites and recordings can only be obtained from the limited number of nerve fascicles

Methods

Results

Conclusion