VEP projections in congenital nystagmus; VEP asymmetry in albinism: a comparison study

Visual evoked potential (VEP) asymmetry in which a preponderance of nasal and temporal retina afferents project to the contralateral hemisphere after full-field monocular stimulation is considered specific to albinism. Some reports, however, suggest that patients with congenital nystagmus (CN) share the albino-like visual pathway anomaly. To examine the clinical specificity of albino misrouting, VEP topography was assessed in ten patients with congenital nystagmus and in ten age-matched albino patients. As an additional control, the VEP response profiles from eight albino patients with no nystagmus were also evaluated. The results are definitive; VEP contralateral asymmetry reflecting temporal retinal misprojection is evinced only in albino patients. Furthermore, ocular-motor instabilities in CN cannot be readily attributed to albino-type misrouted retinal-cortical projections.