Congenital periodic alternating nystagmus

Abstract

Oculography can provide important information where it concerns difficult diagnostic cases. Periodic alternating nystagmus (PAN) was found in a woman presenting with complaints of oscillopsia. The PAN was sometimes associated with a downbeat nystagmus and the recording by electromagnetic induction coils showed features of a leaky neural integrator. PAN is reported with various conditions, demyelination occupying the main place. A congenital form has been described. In our case the only pathology revealed was a split septum pellucidum, pointing in the direction of a kind of septo-optic dysplasia.

Key Words:

• periodic alternating nystagmus
• congenital nystagmus
• anoxia
• De Morsier syndrome