Cochlear implantation influences contralateral hearing and vestibular responsiveness.
A cochlear implant program has been carried out at the ORL Clinic of Semmelweis University in Budapest since 1985. Different devices and techniques have been used in pre- and postlingual children and adults. Over the last 6 years contralateral hearing improvement has been observed in 18 patients. This phenomenon can usually be demonstrated 6 months after the operation. Since our first observation several other authors have confirmed this phenomenon. However, the underlying mechanism is still obscure; both the efferent innervation and the plasticity of the brain may be important factors. The vestibular function of cochlear implant candidates was checked routinely pre- and postoperatively and changes in vestibular responsiveness were observed. Over the last 3 years air-caloric stimulation has been performed by means of a computer-based ENG system. In most patients the vestibular function was unchanged after the implantation. but in some cases a significant improvement in vestibular responsiveness was noted. Here we briefly describe cases of re-implantation carried out at the clinic. All the patients obtained better speech discrimination scores after having been implanted with intracochlear devices. None of the patients suffered any inner ear abnormality due to the first implant.
D000328:Adult; D002648:Child; D019929:Cochlear Implantation; D003054:Cochlear Implants; D004584:Electronystagmography; D006309:Hearing / Q000502:physiology*; D006801:Humans; D012086:Reoperation; D013067:Speech Perception; D014722:Vestibule, Labyrinth / Q000503:physiopathology*