Does the surgical approach in cochlear implantation influence the occurrence of postoperative vertigo?

OBJECTIVE: To investigate the impact of different cochleostomy techniques on vestibular receptor integrity and vertigo after cochlear implantation. STUDY DESIGN: Retrospective cohort study. SUBJECTS: A total of 62 patients (17 to 84 years of age) underwent implantation via an anterior or round window insertion approach. METHODS: Two groups of cochlear implant patients were compared with respect to their pre- and postoperative vestibular function and the occurrence of postoperative vertigo. The data were related to the different cochleostomy techniques. The patients were tested by a questionnaire (dizziness handicap inventory, DIH), caloric irrigation (vestibulo-ocular reflex, VOR) for the function of the lateral SCC and by vestibular evoked myogenic potential (VEMP) recordings for saccular function. RESULTS: Significant differences of postoperative VEMP responses (50% vs 13%) and electromystagmography (ENG) results (42.9% vs 9.4%) were found with respect to the 2 different insertion techniques. The number of patients with vertigo after the surgery as evidenced by DHI (23% vs 12.5%) was significantly different. CONCLUSION: The used round window approach for electrode insertion should be preferred to decrease the risk of loss of vestibular function and the occurrence of vertigo.