The status of astigmatism of 2354 eyes from preschool children in Ningbo

Abstract

Objective To investigate the status of astigmatism and its characters in preschool children.Methods Autorefraction with Canon RK-F1 refractor was performed by optometrists in 1177 cases of 4-6 year-old under natural pupil (non-cycloplegic) condition.Refractive correction was performed in trader-normal VA children after visual acuity was measured.Results 1.The astigmatism rate in preschool children was 50.17%.No significant difference between male and female.2.The incidence rate of low astigmatism (≤1.0D),medium astigmatism (1.25D-2.00D) and high astigmatism (≥2.25D) was 38.83%, 8.07% and 3.27%, re-spectively.No significant difference in every two age group except 3 year-old group and 6 year-old group.3.8.21% low astigmatism, 32.11% medium astigmatism and 6.23% high astigmatism caused abnormal VA.4.The incidence rate of binocular astigmatism was 38.93% including 37.76% symmetry astigmatism.No signifi-cant difference in every two age group.5.Astigmatism with-the-rule was the main type in preschool children,which proportion was 87.89%.The proportion of against-the-rule astigmatism and oblique astigmatism was 5.17% and 6.94%, respectively.Conclusions The incidence rate of astigmatism in preschool children is very high.Medium to high astigmatism always leads to low VA or amblyopia.Autorefraction in preschool children is very important to discover astigmatism and treat amblyopia early, especially in those younger children who are unable to read VA chart.Non-cycloplegic autorefraction is sensitive to discover astigmatism so that it's suitable for screening. Key words: Astigmatism; Preschool children; Non-cyclogic; Autorefraction