ABSTRACT
Three hundred and eighteen of 421 children (76 per cent) registered in Chile's 10 schools for the blind were examined. 84 per cent of these had severe visual loss (severe visual impairment or blindness), which was attributable to hereditary factors in 29.6 per cent, intra-uterine factors in 8.2 per cent, perinatal factors in 22.5 per cent and childhood factors in 11.2 per cent. The aetiology could not be determined in 28.5 per cent. Retinopathy of prematurity (ROP) accounted for 17.6 per cent of all children with severe visual loss; analysis of data by age-group suggested that ROP is becoming an increasingly important cause of blindness. It is estimated that one-half of the children with severe visual loss in Chile have avoidable causes of blindness. The findings are discussed in the light of possible control strategies.
Subject(s)
Blindness/etiology , Eye Diseases/complications , Blindness/diagnosis , Blindness/epidemiology , Child , Child, Preschool , Chile/epidemiology , Eye Diseases/diagnosis , Female , Humans , Infant , Male , PrevalenceABSTRACT
Using World Health Organization definitions of visual loss and a standardised methodology, 905 children were examined in Chile, West Africa and South India. Of these 806 (89%) suffered from blindness (BL) or severe visual impairment (SVI). Causes of SVI and BL were classified anatomically and aetiologically, and avoidable causes identified. In W. Africa (n = 284) the major anatomical cause of SVI/BL was corneal scar/phthisis bulbi (35.9%). Retinal disease accounted for 20.4%, cataract 15.5% and glaucoma 13.0%. Aetiologically 33.8% of SVI/BL was due to childhood factors and 21.1% to hereditary disease. In S. India (n = 305) the major anatomical cause of SVI/BL was corneal scar/phthisis bulbi (38.4%). Retinal disease accounted for 22.6%, cataract 7.4% and glaucoma 3%. Aetiologically 37.0% of SVI/BL was due to childhood factors and 29.8% to hereditary disease. In Chile (n = 217) the major anatomical cause of SVI/BL was retinal disease (47.0%). Cataract accounted for 9.2%, glaucoma 8.3% and 6.9% was due to corneal pathology. Aetiologically 30.4% of SVI/BL was due to hereditary factors, and 20.8% to perinatal factors of which four-fifths (16.6%) was due to retinopathy of prematurity. Avoidable conditions accounted for 70%, 47% and 54% of cases in W. Africa, S. India and Chile respectively.
