The Role Of Materials In Designing Nerve Guidance Channels And Chronic Neural Interfaces

Abstract

A variety of neural electrodes have been developed to simulate and record from axons of the peripheral nervous system. Chronic neural interfaces may be used to facilitate voluntary movement or to control prosthetic devices in patients with spinal cord injuries, amputated appendages, or damaged nerves. Severed nerves are secured within synthetic tubular structures so as to induce and guide regenerating axons through neural interfaces. The regeneration process is strongly influenced by the properties of the tubular guidance channels. Channel characteristics impacting on regeneration include electrical, permeability, and surface microgeometrical properties as well as the ability to release growth factors. Biocompatible electrode materials are essential for insuring axonal survival and accurate signal transduction, especially in long-term use. By maximizing regeneration and providing a compatible neural interface, it may be possible to design implantable devices capable of chronic neural signal transduction in humans. Prosthetic devices and control units connected to neural interfaces could restore motor and sensory function. This review describes current approaches toward the development of nerve guidance channels and chronic neural interfaces.