Diagnosis of idiopathic infantile nystagmus and ocular albinism: a clinical challenge

Abstract

Advances in knowledge concerning the neural circuitry of eye movement control have provided understanding of the pathophysiology of various forms of nystagmus. Furthermore, advances in the molecular genetics and the newer methods of investigation, such as multichannel visual evoked potentials, electroretinograms and optical coherence tomography, have improved the ability to diagnose and differentiate between forms of nystagmus. Diagnosis of oculocutaneous albinism is usually straightforward. However, the clinical diagnosis of ocular albinism is often difficult owing to its varied phenotypical presentation and similarities to idiopathic infantile nystagmus and other congenital nystagmus forms. In our pediatric clinics, we have frequently encountered the misdiagnosis of patients with ocular albinism nystagmus as idiopathic infantile nystagmus instead. The main importance in diagnosing the different types of nystagmus lies in the treatment of these conditions and the visual prognosis, as well as genetic counseling. In this article, the genotypical and phenotypical characteristics of both idiopathic congenital nystagmus and ocular albinism will be highlighted, including the different types of examination required to correctly distinguish between these two types of nystagmus. The clinical characteristics and additional investigations often provide the pieces of a puzzle that need to be fitted together in order to solve diagnostic uncertainty.