Causes and Associations of Amblyopia in a Population-Based Sample of 6-Year-Old Australian Children

Abstract

To describe the prevalence of amblyopia and associated factors in a representative sample of 6-yearold Australian children. Methods: Logarithm of minimum angle of resolution visual acuity (VA) was measured in both eyes before and after pinhole correction, correcting cylindrical refractive components greater than 0.50 diopter (D), and with spectacles (if worn) in a population-based sample of 1741 schoolchildren. Retinal pathological abnormalities were excluded based on photographs. Amblyopia was defined using various best-available corrected VA measures in the absence of significant organic pathological abnormalities. Results: Using the criteria of corrected VA less than 20/40 and at least a 2-line difference between eyes, amblyopia was diagnosed in 13 children (0.7%). The inclusion of children with amblyopia who had been successfully treated (n = 19) increased the amblyopia prevalence to 1.8%. Strabismus or strabismus surgery history was present in 37.5% of the children with amblyopia, anisometropia in 34.4%, both conditions in 18.8%, and isoametropia in 6.3%. Mean corrected VA in amblyopic eyes was 37.7 logarithm of minimum angle of resolution letters (Snellen VA equivalent Ͻ20/40), ranging from 0 to 48 logarithm of minimum angle of resolution letters (Snellen VA equivalent Ͻ20/200-20/25). Most amblyopic eyes (58.7%) were significantly hyperopic (spherical equivalent Նϩ3.00 D); 8.7% were myopic. Conclusions: A relatively low prevalence of amblyopia in a sample of 6-year-old children is documented. The majority of these children had already been diagnosed and treated for this condition.

Patterns of Eyecare Utilization by Young Australian Children: Findings from a Population-Based Study

“…We recently reported that a relatively high proportion (47%) of all amblyopic children in this population had been successfully treated, attaining corrected visual acuity ≥20/40 in the affected eye. 18 Given that access to and availability of professional eyecare services are generally similar in most major towns and cities, this finding is probably generalizable to most Australian urban and sub-urban cities, and therefore points to the likely effectiveness of detection strategies currently in place in Australia.…”

Refractive Errors in School-age Children in Qazvin, Iran

“…In studies on Singaporean 30 to 72-month old children, 7-year-old children in the United Kingdom and Australian children aged 6 years; the prevalence of amblyopia was 1.19%, 3.6% and 0.7%, respectively (54)(55)(56). The reported prevalence of amblyopia in a questionnaire-based study on Japanese children aged between 1.5 and 12 years was between 0% to 0.2% and this amount in Korean children aged 3 to 5 years was 0.4% of the 43% who responded (57)(58)(59).…”

Stereoacuity and ocular associations at age 12 years: Findings from a population-based study

“…28 Criterion A. All children with best-corrected visual acuity Ͻ 20/20 not attributable to organic disease of the eye or visual pathway were included as potential cases.…”