Acquired ocular visual impairment in children. 1960-1989
G. C. Robinson and J. E. Jan
Department of Paediatrics, Faculty of Medicine, University of British Columbia, Vancouver, Canada.
OBJECTIVE--To describe the causes, sites, and types of eye anomaly and
associated handicaps in children identified in the last 30 years with
ocular visual impairment of 20/200 (6/60) or worse in the better eye with
correction. DESIGN--Trend study. STUDY POPULATION--Children in British
Columbia younger than 19 years with visual loss diagnosed between January
1960 and December 1989 who were referred for multidisciplinary assessment.
RESULTS--The incidence of acquired ocular visual impairment has decreased
from 0.6 to less than 0.2 per 10,000 people aged 19 years or younger during
the last 30 years. The most common cause was a genetic cause, followed by
tumor, injury, infection and autoimmune disorders. Optic nerve atrophy and
retinal disorders together resulted in more than 90% of all ocular lesions.
Gender distribution revealed more males than females to be affected.
Sixty-six percent of children had enough sight to read. The percentage of
affected children with neurologic disabilities has increased overall in the
last 30 years because more children with profound brain damage have
survived. CONCLUSIONS--Acquired ocular visual impairment is rare. The
incidence of such impairment has been reduced by two thirds in the last 30
years. This decline has had little impact, however, because most cases of
blindness are due to congenital conditions. The number of cases of acquired
blindness is only one fourth that of congenital blindness, which has begun
to increase again owing to the reemergence of retinopathy of prematurity.
