Correctable and Non-Correctable Viual Impairment in a Population-Baed ample of 12-Year-Old Autralian Children Original Reearch Article

Purpoe To document the prevalence of correctable and non-correctable viual impairment in a repreentative ample of Autralian children, predominantly age 12 year. Deign Population-baed cro-ectional tudy. Method Logarithm of the minimum angle of reolution (logMAR) viual acuity wa meaured in both eye unaided, with pectacle if worn, and after ubjective refraction if required, in 2353 children, examined during 2004 to 2005. Cycloplegic autorefraction (uing cyclopentolate) and dilated fundu examination were performed. Uing a cut-off of 0.3 logMAR unit (<20/40), preenting viual impairment wa defined uing unaided viual acuity if pectacle were not worn or with uual correction if pectacle were worn. Impairment not eliminated by refraction wa conidered non-correctable; any difference between thi and preenting impairment wa defined a correctable impairment. Myopia wa defined a pherical equivalent refraction (ER) ≤−0.50 diopter (D), hyperopia a ER ≥+2.0 diopter, aniometropia a ER difference ≥1.00 diopter, and atigmatim a cylinder ≥1.0 diopter. Amblyopia wa defined a corrected viual acuity <0.3 logMAR not attributable to an underlying tructural eye or viual pathway abnormality. Reult Viual impairment wa found in the wore eye of 117 children (5.0%) and compried correctable (82%) and non-correctable impairment (18%). Correctable impairment wa due to myopia in 67 (69.8%), hyperopia in 11 (11.5%) and atigmatim in 32 ubject (33.3%). Caue of non-correctable impairment were: amblyopia 66.7%, congenital glaucoma 9.5%, optic nerve hypoplaia 9.5%, congenital nytagmu 4.8%, and cortical blindne 4.8%. Concluion Viual impairment had a relatively low prevalence in thi older childhood population, a large proportion of which wa correctable by refraction alone.