Peripapillary retinal nerve fibre layer thickness and its association with refractive error in Chinese children: the Anyang Childhood Eye Study

Meng‐Tian Kang, Shi‐Ming Li, He Li, Lei Li, Si‐Yuan Li, Bi‐Dan Zhu, Yi‐Qin Guo, Bo Meng, Yun‐Yun Sun, Anran Ran, Yi‐Peng Wang, Luo‐Ru Liu, Si‐Yan Zhan, Ravi Thomas, Ningli Wang

To report the thickness of the peripapillary retinal nerve fiber layer (pRNFL) in Chinese children and examine it's association with refractive error, axial length and optic disc parameters. Population based, cross-sectional study. A total of 2893 seven-year-old children from 11 randomly selected primary schools in Anyang, central China. Participants underwent ophthalmic examinations including optical biometry, cycloplegic autorefraction, and SD-OCT. RNFL thickness in 16 radial sections, cycloplegic spherical equivalent, axial length. The mean (SD) average RNFL thickness was 102.01(8.02)µm. The average RNFL thickness decreased with smaller disc area (r = 0.18, R(2)  = 0.03, P < 0.0001), bigger cup area (r = -0.11, R(2)  = 0.01, P < 0.0001), smaller rim area (r = 0.28, R(2)  = 0.08, P < 0.0001), smaller nerve head volume (r = 0.27, R(2)  = 0.07, P < 0.0001), longer axial length (r = -0.15, R(2)  = 0.02, P < 0.0001) and a negative spherical equivalent (r = 0.11, R(2)  = 0.01, P < 0.0001). Hyperopic children had a thicker RNFL than emmetropic children [102.45(8.13)µm vs. 100.81 (7.18)µm, P < 0.001]. Myopic children had thinner RNFL than emmetropic children [99.17 (7.69)µm vs. 100.81 (7.18)µm, P < 0.05]. RNFL thickness decreased with increasing axial length, higher myopia, bigger cup area, smaller disc and rim area, and a smaller nerve head volume but the coefficient of determination for all these associations was small. The RNFL in myopes was significantly thinner than emmetropes or hyperopes, but with small absolute differences. The study provides RNFL values for healthy 7-year-old Chinese children. Follow up of this cohort to observe the change of RNFL thickness with myopia and possible change in detected associations with age is planned.