Fixation Suppression of Vestibulo-ocular Reflex in Elderly Patients with Disequilibrium: Significance of Cerebral Lesions on MRI

In this retrospective study, the authors asked whether the presence of cerebral lesions (lacunar infarcts and/or white matter lesions) on magnetic resonance images (MRI) affected vestibulo-ocular reflex (VOR) gain, fixation-suppressed VOR (fVOR) gain, and visual suppression rate (VSR) in 46 elderly patients with disequilibrium symptoms treated at Department of Otolaryngology, Matsue City Hospital between January 2004 and December 2004. The VOR and fVOR were examined with manually-rotated sinu-soidal stimuli using an infrared camera system. VOR gain in the dark did not differ significantly, irrespective of the MRI findings. On the other hand, fVOR gain in patients with cerebral lesions was significantly higher than that in patients without cerebral lesions, resulting in significantly lower VSR in the former patients. Impairment of visual suppression of VOR due to brain lesions outside the cerebellum or pons may not be uncommon in the elderly.