Oscillopsia in patients with loss of vestibular function.

Contrary to standard teaching, many patients with bilateral vestibular loss clearly deny oscillopsia or imbalance in darkness. In an attempt to characterize these patients within the larger population of all patients with bilateral vestibular loss, the rotation and posturography test results of 22 patients with bilateral vestibular loss were reviewed. In addition, dynamic visual acuity was assessed with an eye chart test. There was a poor relationship between oscillopsia and dynamic visual acuity or rotation testing. There were three patterns of response on rotation testing, and loss of high-frequency gain was seen in as many patients who reported oscillopsia as did not. There were some patients with normal gain values at all frequencies tested who reported oscillopsia. It may be that the change in the VOR, rather than the absolute VOR loss, is responsible for the production of oscillopsia. On the basis of this and other studies, treatment strategies for patients with bilateral vestibular loss are suggested.