Abstract
Purpose:
We aimed to describe the distribution of peripheral refraction and its associations with refractive error in a population of year 1 Chinese children in central China.
Methods:
Cross-sectional analysis of the Anyang Childhood Eye Study (ACES), a school-based cohort study.Cycloplegic central and peripheral refraction (15° and 30° at nasal and temporal retina, respectively) was measured using an open field, infrared autorefractor. Only right eyes were included for analysis.
Results:
A total of 2645 year 1 students (85.0% of the ACES eligible participants) aged 7.1 (5.7~9.3) years old had peripheral refraction measured at baseline. At baseline, there were 1353 children with hyperopia (>1.0 D, 51.2%), 1125 with emmetropia (-0.49 to 1.0 D, 42.5%), 161 with low myopia (-2.99 to -0.5 D, 6.1%), 6 with moderate and high myopia (<=3.0 D, 0.2%). Peripheral refraction of 15° and 30° at nasal and temporal retina shifted to be more myopic with increasing central myopia (P<0.001). Compared with central refraction, hyperopic children had relative myopia at nasal 15°, temporal 15°, nasal 30°, and temporal 30° retina (-0.49, -0.52, -0.33, and -0.52 D, P<0.0001). Emmetropic children also had relative myopia at nasal 15° and temporal 15° retina (-0.41 D, -0.37 D, P<0.0001), which was decreased to be slightly relative myopia at nasal 30° and temporal 30° retina (-0.13 D, -0.06 D, P<0.0001). Children with low myopia had relative myopia at nasal 15° and temporal 15° retina (-0.38 D, -0.20 D, P<0.0001), but relative hyperopia at nasal 30° and temporal 30° retina (0.25 D, 0.37 D, P<0.0001). Children with moderate to high myopia also had relative myopia at nasal 15° and temporal 15° retina (-0.27 D, -0.09 D, P<0.001), and higher relative hyperopia at nasal 30° and temporal 30° retina (0.60 D, 0.96 D, P<0.001).
Conclusions:
In young Chinese children, peripheral refraction presents to be relatively hyperopic in myopic eyes at 30° retina, and relatively myopic in emmetropic and hyperopic eyes at all eccentricities, with temporal retina being more hyperopic compared to nasal retina.
Keywords: 605 myopia •
511 emmetropization •
677 refractive error development