Vestibulo-ocular reflex abnormality in Vogt-Koyanagi-Harada syndrome.

The eye movements of 15 patients with Vogt-Koyanagi-Harada (VKH) syndrome were analysed. Transient dizziness occurred in 60% of the patients. Eight patients (53%) exhibited horizontal jerk nystagmus that was completely inhibited by visual fixation. Eight cases (53%) exhibited the elevation of vestibulo-ocular reflex (VOR) gain in darkness. Six of the patients with nystagmus had defective smooth pursuit movements with reduced gain on the side ipsilateral to the nystagmus. Saccadic and optokinetic eye movements were intact, and visual vestibular interaction was also normal. Impaired eye movements in VKH syndrome may be caused by asymmetry of the vestibular function secondary to the labyrinthine inflammation.