Low prevalence of visual impairment seen in Australian children

May 3, 2005

Young school children living in Sydney, Australia, were found to have a low prevalence of visual impairment, according to the results of a population-based, cross-sectional study, reported by Dana Robaei, MD.

May 3

- Fort Lauderdale, FL - Young school children living in Sydney, Australia, were found to have a low prevalence of visual impairment, according to the results of a population-based, cross-sectional study, reported by Dana Robaei, MD.

The Sydney Myopia Study examined the eyes of 1,740 school children between the ages 6 and 7 during 2003 and 2004. The mean uncorrected visual acuity was 20/32 or 49.6 +/-0.2 letters. Boys had slightly better vision than girls overall, said Dr. Robaei of the University of Sydney, Australia.

Only 4.1% of the children in the study were found to have any visual impairment in at least one eye. However, children of lower socioeconomic status had significantly more visual impairment, she noted.

"Uncorrected refractive error accounted for 69% of visual impairment in our sample and amblyopia was the second most common cause. We found a retinal disorder in only 2.8% of the sample and that was due to Coats' Disease, ocular albinism, and foveal pits, which were detected on OCT," Dr, Robaei noted.

Astigmatism accounted for the largest proportion of visual impairment due to refractive error, at 34.6% of those with visual impairment, she noted. "Overall, uncorrected astigmatism was the commonest cause of visual impairment in the study."

In the children with visual impairment in at least one eye that was due to refractive error, myopia accounted for a small proportion of visual impairment and all had received glasses. On the other hand, astigmatism, seen in a larger number of cases with visual impairment, had not been corrected with prescription glasses in most cases, Dr. Roaei said.

"At the time of the study, 4.4% of the children were wearing prescription glasses to correct refractive error," she said. "A significant proportion of children (one-third) had been prescribed glasses in the absence of significant refractive error."