title: Causes of visual impairment in children seen at a university-based hospital low vision service in Brazil.
abstract: OBJECTIVE
  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.
authors.affiliation: Pediatric Low Vision Division, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Cristina Helena Toledo
authors.initials: CH
authors.lastname: de Paula
authors.affiliation: Pediatric Low Vision Division, Federal University of Minas Gerais, Belo Horizonte, Brazil. Electronic address: galton@lua.com.br.
authors.forename: Galton Carvalho
authors.initials: GC
authors.lastname: Vasconcelos
authors.affiliation: Retina Division, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Márcio Bittar
authors.initials: MB
authors.lastname: Nehemy
authors.affiliation: Divisions of Pediatric Ophthalmology and Eye Alignment Disorders, University of California, San Diego.
authors.forename: David
authors.initials: D
authors.lastname: Granet
mesh_terms: D001766:Blindness / Q000453:epidemiology*; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002662:Child Health Services / Q000706:statistics & numerical data; D002675:Child, Preschool; D005128:Eye Diseases / Q000453:epidemiology*; D005260:Female; D006785:Hospitals, University / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012017:Referral and Consultation; D012189:Retrospective Studies; D012424:Rural Population / Q000706:statistics & numerical data; D014505:Urban Population / Q000706:statistics & numerical data; D015354:Vision, Low / Q000453:epidemiology*; D019987:Persons with Visual Disabilities / Q000706:statistics & numerical data*