Causes of visual impairment in children seen at a university-based hospital low vision service in Brazil.

Purpose: To evaluate the epidemiologic characteristics of patients 0-7 years of age with visual impairment registered at a university hospital low vision service in Brazil.

Methods: The medical records of visually impaired patients were retrospectively reviewed for sociodemographic characteristics and ocular and associated deficiencies. In addition to biographical information, the following data were collected: ocular disorders, diagnosis, affected anatomic region, etiology, and avoidable or unavoidable causes.

Results: A total of 229 patients were included, 65% of whom were referred from rural health centers. The mean age at first appointment was 39.4 months. Associated nonophthalmic disorders were present in 47% of patients. The most prevalent disorders were congenital cataract (14%), toxoplasmosis (14%), and congenital glaucoma (13%). The most commonly affected anatomic regions were the retina (18%) and lens (15%); 33% had a normal-appearing globe. Using World Health Organization classifications, the most prevalent underlying etiologies were undetermined (43%), perinatal/neonatal factors (22%), and intrauterine factors (20%). Avoidable causes were found in 64% of the children.

Conclusions: The three leading causes of infant blindness in our patient cohort were congenital cataract, toxoplasmosis, and congenital glaucoma. The most commonly affected anatomic regions were retina, lens, and normal-appearing globe. The percentage of avoidable causes of impairment was high and the mean age at first appointment was late.