Pediatric cochlear implantation in cochlear malformations

Objective: This study aimed to present relevant information about pediatric cochlear implantation in malformed cochleas based on the experience gather ed with 12 implanted children. Study Design: A retrospective analysis was performed. Setting: All patients were diagnosed and implanted at the Medical Universit y of Hannover. Medical check-ups were performed regularly. The rehabilitati on concept was developed by the Cochlear Implant Center of Hannover. Patients: All children were female and were between 2 and 13 years of age a t the time of implantation, with the average age being 4 years and 2 months . Only patients who were younger than 14 years of age and implanted between September 1992 and October 1995 were evaluated. Intervention: Diagnostic computed tomographic scans including three-dimensi onal reconstructions and magnetic resonance imaging images were performed. In all cases, Nucleus devices (Mini 22 or 20 + 2) were implanted. Medical U niversity of Hannover standard surgical technique was used, although in mos t cases, facial nerve monitoring and electrically evoked auditory brain ste m responses were additionally recorded. Total or partial obliteration of th e middle ear had occurred in two cases. An anteroposterior approach was use d four times. The implantation was followed by the standard rehabilitation procedure for children. Results: No serious complications occurred. All children responded to acous tic stimuli and showed improvement in their speech production. However, one autistic child performed poorly, and for another child suffering from a CH ARGE syn drome, results still are pending. Conclusions: Given suitable preconditions, cochlear implantation is feasibl e with an acceptable risk of complications. Implantation appears to be bene ficial in most cases with cochlear malformations provided that eighth nerve and cochlear lumen are present.