Visual acuity and retinal changes in South Australian Aborigines

Eye examinations were carried out a four Aboriginal reserves. Of 361 Aboriginal adults tested, 64 had a visual defect (visual acuity of 6/9 or worse) in each eye, a prevalence of 18%, with an additional 79 (22%) with a similar loss of acuity in one eye only; these were more frequently seen at the urbanized reserve of Koonibba. Only one full blood Aboriginal child within the less urbanized communities had a reduced visual acuity, whereas seven (10%) part blood children at a more urbanized reserve had reduced vision in both eyes, with a further nine (13%) in one eye only, not unlike figures quoted for South Australian school children. Vascular changes in the fundus oculi were observed and occurred more often when hypertension and/or hyperglycaemia were present. They consisted of arteriovenous crossing changes (26%), swelling of the retinal veins (3%) and altered light reflex (41%) and were not infrequently seen in the younger adult (20% of adults under 30 years had AV crossing changes and 46% had widened light streak). Analysis suggests that, although hypertension and hyperglycaemia are related to retinal vascular changes, other factors, as yet unidentified, are present in the Aboriginal population under consideration.