The tissue response to a chronically implanted cochlear electrode array can vary from a minimal response (a) to a more active foreign body reaction (b). The present study is designed to investigate techniques to reduce the tissue response while improving the electrical properties of the cochlear implant electrode array. Scale bar = 200 um. Image courtesy of the Bionics Institute.
Cochlear implants have made a dramatic impact on the quality of life of over 400,000 severe-profoundly deaf patients. While existing cochlear implant technology has been shown to be safe, their clinical efficacy can be significantly improved. The implantation of an electrode array evokes a local neuro-inflammatory response that can play a critical role in the long-term performance of the device. In addition, they must stimulate neural tissue using strict safety guidelines. Maximum safe stimulation using platinum (Pt) (the current material of choice), is restricted to relatively levels in order not to generate adverse electrochemical reactions. The aim of this project is to trial advanced electrode materials designed to reduce the inflammatory process while allowing a greater window of safe stimulation parameters.