Vestibular Outcome After Cochlear Implantation Is Not Related to Surgical Technique: A Double Blinded, Randomized Clinical Trial of Round Window Approach Versus Cochleostomy.

OBJECTIVE: To establish whether the round window approach (RWA) leads to less vestibular dysfunction and dizziness than the standard cochleostomy approach (SCA) during cochlear implant (CI) surgery, as assessed using the video head impulse test (vHIT).Additionally, objective findings were compared with the subjective dizziness perceived by the patient.

STUDY DESIGN: Double blinded, clinical randomized trial.

SETTING: University Hospital.

PATIENTS: Fifty-two ears from 46 patients were included. Inclusion criterion was a gain value more than 0.50.

INTERVENTION: Patients were randomized to the RWA or the SCA. Evaluation with the vHIT was performed before surgery, 1 day after surgery, and 1 month after surgery. Subjective dizziness was measured using a visual analogue scale (VAS) and the dizziness handicap inventory (DHI).

MAIN OUTCOME MEASURES: Gain values and the incidence of catch-up saccades.

RESULTS: Three out of 23 patients in the SCA group experienced catch-up saccades compared with no patients in the RWA group, indicating the occurrence of objective vestibular dysfunction after CI surgery; the difference was not statistically significant. The VAS increased in both groups the day after surgery. The difference between the groups was not statistically significant. No statistically significant changes in the gain value or the DHI score could were observed between the two groups.

CONCLUSION: No statistically significant difference between the cochleostomy approach and the round window approach using the vHIT and subjective dizziness perceived by the patient was found.