Strabismus, significant refractive errors found in cross-section of Iranian children

Optom Vis Sci. 2009;86(4):364-369.

A sizeable proportion of children entering Iranian schools were identified as having strabismus or significant refractive errors, according to a study.

"The relatively high rate of hyperopia and astigmatism in the studied population needs more attention," the study authors said. "The results of the study emphasize the need for adequate diagnostic and therapeutic eye care services for preschool children."

The cross-sectional population-based study included 815 randomly selected 6-year-old children enrolling in schools in Shahrood, Iran. Children with organic blindness and mental retardation were excluded.

An optometrist recorded ocular alignment, visual acuity, stereopsis, cover testing and cycloplegic refraction. Amblyopia was defined as best corrected visual acuity of 6/12 or less in one or both eyes or a bilateral difference of at least two lines of BCVA.

The prevalence of significantly diminished visual acuity (uncorrected visual acuity of 6/12 or less in either eye) was 3.6%. The prevalence of amblyopia was 1.7%.

Hyperopia greater than 2 D was identified in 20.5% of children; myopia greater than 0.5 D was found in 1.7%. The prevalence of astigmatism that was 0.75 D or higher was 19.6%.

Hyperopia greater than 3.5 D was identified in 2.1% of children; myopia greater than 3 D was found in 0.1% of children. Astigmatism greater than 1.5 D was seen in 5% of the group. Strabismus was identified in 1.2% of the sample. Data also showed 6.4% of children were at risk for developing amblyopia.