Electrooculographic Study of Latent Nystagmus

ABSTRACT

The authors analysed eleven patients with latent nystagmus who were diagnosed by clinical manifestation and electrooculography during six months. Among them, six patients had monocular amblyopia, four had binocular amblyopia and only one had normal visual acuity. All of them had manifest latent nystagmus which had a small amplitude of nystagmus in binocular fixation. Two of them showed typical latent nystagmus, jerky wave form characterized by decreasing velocity in slow phase and directing to fixing eye. Seven patients showed typical latent nystagmus wave form associated with pendular wave form and two patients showed jerky wave form with increasing velocity in slow phase. Therefore nine patients had componant of infantile nystagmus wave form. Ten of them had strabismus. Among them, five patients had hyper tropia. Three of the hypertropic patients showed dissociated vertical deviation. The authors suggest that the latent nystagmus is a kind of infantile nystagmus, and abnormal ocular conditions such as strabismus and amblyopia affects the infantile motor nystagmus.