Objective: To determine the impact of cochlear implantation (CI) on the vestibular function.
Methodology: Prospective cohort study done on twenty seven adult patients before and after CI. Vestibular function was assessed using clinical vestibular examination, caloric video-nystagmography (VNG), vestibular-evoked myogenic potentials (VEMP), sensory organization test of computerized dynamic posturography (S0T-CDP) and Dizziness Handicap Inventory (DHI).
Results: 27 adult CI candidates were tested one week before and eight weeks after CI. In caloric test, new hypo-reflexia was found in three subjects and areflexia in another three subjects ipsilateral to the implanted ear. VEMP showed either a disappearance of response or an increase in threshold by >10dB in 15 ears postoperatively. SOT of CDP showed abnormal response in condition 6 only in two subjects. DHI scores worsened in five patients.
Conclusions: It is important to do vestibular function tests before CI to educate CI candidates about possible risk to balance function. Also, to think more and more before doing CI on only balancing ear.