Facial nerve stimulation after Nucleus 22-channel cochlear implantation.

OBJECTIVE To review the clinical features, radiographic findings, and programming strategies used in our population of patients who developed facial nerve stimulation after cochlear implantation. STUDY DESIGN AND SETTING Patients referred to our nonprofit, outpatient facility were studied prospectively. PATIENTS The study consisted of 14 patients with facial nerve stimulation after placement of the Nucleus 22-channel cochlear implant. INTERVENTIONS Records were reviewed retrospectively, and patients were studied with three-dimensional computed tomographic scanning techniques. Electrical testing was performed, and various cochlear implant programming strategies were evaluated. MAIN OUTCOME MEASURES Important clinical features were reviewed. The radiographic and anatomical relationships of the facial nerve to the cochlea were evaluated, and the programming strategies used to effectively control facial nerve stimulation were reviewed. RESULTS Prevalence of facial nerve stimulation in our population was 7%. The most common cause was otosclerosis. Anatomical data confirmed the close proximity of the basal turn of the cochlea and the labyrinthine segment of the facial nerve. There was a high correlation between the electrodes causing symptoms and those found radiographically to be closest to the labyrinthine segment of the facial nerve. We were able to control facial nerve stimulation in all patients through programming mode changes. CONCLUSIONS Otosclerosis appears to be a risk factor for developing facial nerve stimulation after cochlear implantation, and the site of stimulation appears to be the labyrinthine segment of the facial nerve. Familiarity with more elaborate programming techniques is critical to managing patients with this complication.