A Case of Pendular Nystagmus: Delayed Onset of Infantile Nystagmus

Pendular nystagmus (PN) is characterized by quasi-sinusoidal oscillations of the eyes disrupting visual acuity and causing oscillopsia. PN can be classified into congenital and acquired form. Infantile nystagmus (IN) describes a syndrome of involuntary, pathological oscillations of the eyes that are almost invariably conjugate, symmetrical and horizontal. The numerous afferent visual system pathologies associated with IN make it difficult to establish etiology, and furthermore, a sizable proportion of IN cases do not appear to be associated with any ocular pathology whatsoever (these are referred to as ‘idiopathic' or ‘isolated' IN).