Engineering Challenges in Cochlear Implants Design and Practice

Since the first successful cochlear implantation in the early 1970s by the House group in Los Angeles, about 120,000 patients have received cochlear implants (CI) worldwide, with more every year [1]. The premise of using electrical stimulation on the sensory nerves, either for visual or acoustic perceptions, is not new. Attempts were made in the 19th century by several researchers with backgrounds in engineering and/or medicine. The only documented account for that period was one by Volta and it was an accidental observation when he applied an electrical current into his ear canals. When this current was applied, he reported he heard a bubbling or crackling sound. Many years later, the first human implant was performed by an engineer/physician team of Djourno and Eyries in 1937. Unfortunately, it was obscurely published, and at the brink of war was therefore largely neglected until the 1970´s. The concept was then resurrected by the National Institutes of Health (NIH) with funding to support researchers in U.S. and subsequently in Australia and Europe.