[Vertical vergences. I. Physiological and pathological aspects].

The vertical vergences are rather weak physiological conjugate movements of the eyes. When the ocular axes approach each other or deviate, a vertical convergence or divergence occurs. These reflex movements are evoked either by visual stimuli (fusional vergence) or by labyrinthine stimuli. In pathological situations vertical vergences may become evident in permanent or alternating hyperphorias, in the strabismus occurring in the Hertwig-Magendie syndrome, in see-saw nystagmus and in labyrinthine lesions (such as Meniere's disease, after labyrinthectomy and after section of the VIIIth nerve).