Partial insertion of the nucleus multichannel cochlear implant: technique and results

The goal of cochlear implant surgery is to insert the entire electrode array into the scala tympani. Incomplete insertion is usually attributable to the presence of new bone formation as a result of meningitis. Surgical techniques for dealing with obstruction include various degrees of drilling of the cochlea or alternative placement of the electrode array. We evaluated the postoperative performance of eight such patients implanted with the Nucleus multichannel cochlear implant at NYU Medical Center as well as data from adults and children nationwide. Scores ranging from marginal closed-set speech discrimination to 40 percent on open-set speech recognition tests were obtained. Surgical procedure, placement, and number of electrodes as well as number of channels in use affect the ultimate performance of these patients.