Nystagmus reactions among patients with asymptomatic cerebrovascular diseases: results and analysis of investigation of 228 persons.

The aim of this investigation was to view characteristics of vestibular nystagmus (spontaneous, latent, and positional) through Frenzel's spectacles in patients with asymptomatic cerebrovascular disease (ACVD), with the intent of providing an early diagnosis and appropriate prophylaxis. We examined a total of 228 men (mean age, 48.04 +/- 7.8 years), a mean group of 150 men with proven asymptomatic cerebrovascular disease, and 78 clinically healthy men. Vestibular nystagmus was investigated through Frenzel's spectacles. The following characteristics (qualitative and quantitative) were studied: degree and direction form, association, continuity, frequency, and amplitude. It was found that in patients with proven ACVD, latent nystagmus is prevalent. The symptom of positional nystagmus is much more frequent than that of spontaneous nystagmus and is often the first objective symptom of initial disturbances of the cerebral blood flow in the region of the vertebrobasilar system. The vestibular system is mainly labyrinthine in origin, becoming later of central origin.