Acquired Pendular Nystagmus: Characteristics, pathophysiology and pharmacological modification

Abstract

Pendular nystagmus is an oscillatory movement of the eye which has a sinusoidal rather than a “saw-tooth” wave form (Figure 1). It may be congenital, acquired in association with neurological diseases, or voluntary (trick nystagmus). This report discusses the manifestations of acquired pendular nystagmus in 20 of our own patients together with a further 32 cases from the literature. Complete clinical details of these patients have been published elsewhere (Gresty et al, 1982). Albeit a rare disorder, pendular nystagmus is important because of its implications for the organisation of the oculomotor system, the pathophysiology of tremor and for the severe visual handicap it may produce. For the latter reason emphasis has been laid on the pharmacological modification of the nystagmus with a view to treatment.