Observations on an experimental expansile electrode for use in cochlear implantation.
Cochlear implants in children must be designed to allow for a child's growth and maturation. An experimental animal study was performed to document the influence of head growth on a prototype expansile electrode system. Seven kittens were implanted with a stimulated electrode which had been coiled to allow for a two-to-one expansion in length. Head growth was monitored both by direct skull measurements and by serial radiography. The animals were sacrificed when they had reached maturity and the implanted devices were studied. When implanted in subcutaneous tissue, the coils became encased in fibrous tissue, while within air-containing spaces, such as the bulla, they distended freely. This suggested that a route which maximized the amount of air-containing space traversed by an electrode should be the preferred route for a cochlear implant in children.
D000818:Animals; D002415:Cats; D003051:Cochlea / Q000473:pathology; D003054:Cochlear Implants; D004567:Electrodes, Implanted; D005069:Evaluation Studies as Topic; D006257:Head / Q000000981:diagnostic imaging / Q000254:growth & development; D011474:Prosthesis Design; D011859:Radiography