Aetiology of childhood vision impairment, metropolitan Atlanta, 1991-93

Data from the population-based Metropolitan Atlanta Developmental Disabilit ies Surveillance Program (MADDSP) were used to describe the underlying caus es of vision impairment (VI; corrected visual acuity in the better eye of 2 0/70 or worse) in young children (n = 228) in metropolitan Atlanta in 1991- 93. Children with VI were identified through record review at multiple educ ational and medical sources. Children were categorised as having isolated V I or multiple disabilities (i.e. VI plus one or more of four additional dev elopmental disabilities) and as having low vision (visual acuity 20/70-20/4 00) or blindness (visual acuity worse than 20/400). Medical conditions abst racted from MADDSP sources were reviewed to determine the probable aetiolog y of a child's VI. Aetiologies were assigned to one of three developmental time periods: prenatal, perinatal, or postnatal. Prenatal aetiologies were identified in 43% of the children; 38% of the prenatal aetiologies were gen etic. Perinatal aetiologies were found in 27% of the children. Postnatal ae tiologies were rare. Prenatal aetiologies were more common in children with isolated VI; perinatal and postnatal aetiologies were more common in child ren with multiple disabilities. Children with prenatal aetiologies tended t o have less severe vision loss than did children with perinatal or postnata l aetiologies. The distribution varied by birthweight, but did not differ s ignificantly by sex or race.