Epileptic nystagmus in a patient with nonconvulsive status epilepticus.

Epileptic nystagmus (EN) is a rare form of rhythmic eye oscillations occurring during seizure activity. Not only convulsive states, but also nonconvulsive status may represent with EN and this phenomenon may be the only motor manifestation of seizure activity. Epileptic activation of a cortical saccade region may be distinguished from activation of a cortical pursuit region clinically as activation of pursuit regions results in nystagmus slow phases that bring the eyes across the midline. Horizontal EN results most commonly from seizure activity involving the occipital cortex. In this report, horizontal EN in a patient with nonconvulsive status epilepticus (NCSE) is described with clinical, radiological and electrophysiological findings that occur probably due to posterior leukoencephalopathy syndrome.