Visual Function and Ocular Pigmentation in Albinism

To study the relationship between visual function and ocular (iris, retina/choroidal) pigmentation in patients with albinism and other hypomelanotic disorders. To identify the carrier state in relatives of patients with ocular albinism.

Visual function and ocular pigmentation are being studied in patients with albinism and other disorders associated with hypopigmentation. The degree of ocular pigmentation is assessed clinically by estimating the melanin content of the iris, retinal pigment epithelium, and choroid. Visual function is measured in the conventional manner to study central vision, and electrophysiological methods to detect a misrouting of the visual pathways. The purpose of this study is to document the visual deficit and the pigmentary changes of patients with albinism, to observe their natural course, and to determine whether misrouting of the visual pathways is present and is correlated with pigmentation.

Patients have been recruited into the study by referral from an ophthalmologist or pediatrician. Entrance into the study was dependent upon clinical evidence of decreased or absent pigmentation in skin, hair, and/or eyes. The definition was purposefully broad to include the broad range of phenotype variations and clinical heterogeneity. The purpose of the study id to be able to document iris and retina/choroidal pigmentation and correlated these finding with visual function.

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