Vestibular rehabilitation using visual displays: Preliminary study

Objectives/Hypothesis: Interactive computer displays can alter vestibular function. We hypothesized that by placing a vestibulopathic subject with chronic vertigo in a computer scene, slowing the visual scene motion to a rate slightly higher than their vestibulo-ocular reflex (VOR) gain, and gradually speeding up the scene, we could cause VOR improvement and symptom reduction. Study Design: Randomized, non-blinded treatment/control study. Methods: Subjects were selected for VOR gain less than 0.5 at 0.16, 0.32, or 0.64 Hz. They wore a computer display that interacted with the movement of their head. The scene magnification controlling image motion was initially set approximately 5% higher than the VOR gain. Subjects had interaction tasks for 10 sessions of 30 minutes twice daily for 5 days. The scene magnification was gradually increased over the sessions. Control subjects had a similar procedure but were shown a normal, x 1.0 magnification for each interaction session. Results: Nine subjects and six control subjects were tested. Test subjects showed an average increase in VOR gain of 0.05 at 0.16 Hz, 0.048 at 0.32 Hz, and 0.098 at 0.64 Hz. In contrast, control subjects showed a decrease of 0.008 at 0.16 Hz, an increase of 0.016 at 0.32 Hz, and a decrease of 0.058 at 0.64 Hz. Improvement remained after 1 week but at a lower level than immediately after testing. Subject Dizziness Handicap Inventory scores decreased by 2.8 from 38.5 in the first week. Control subjects reported no symptom improvement. Conclusion: Immersive computer environments can improve VOR function and reduce vertigo.