Recovery of dynamic visual acuity in bilateral vestibular hypofunction

Objective: To determine the effect of vestibular exercises on the recovery of visual acuity during head movement in patients with bilateral vestibular hypofunction (BVH). Design: Prospective, randomized, double-blinded study. Setting: Outpatient clinic, academic setting. Patients: Thirteen patients with BVH, aged 47 to 73 years. Intervention: One group (8 patients) performed vestibular exercises designed to enhance remaining vestibular function, and the other (5 patients) performed placebo exercises. Main Outcome Measures: Measurements of dynamic visual acuity (DVA) during predictable head movements using a computerized test; measurement of intensity of oscillopsia using a visual analog scale. Results: As a group, patients who performed vestibular exercises showed a significant improvement in DVA (P=.001), whereas those performing placebo exercises did not (P=.07). Only type of exercise (ie, vestibular vs placebo) was significantly correlated with change in DVA. Other factors examined, including age, time from onset, initial DVA, and complaints of oscillopsia and disequilibrium, were not significantly correlated with change in DVA. Change in oscillopsia did not correlate with change in DVA. Conclusions: Use of vestibular exercises is the main factor involved in recovery of DVA in patients with BVH. We theorize that exercises may foster the use of centrally programmed eye movements that could substitute for the vestibulo-ocular reflex.