The Correlation of Visual Quality, Eye Refraction and Structural Parameters in Schoolchildren with Low Myopia

Abstract

Objective: To study the correlation between wavefront aberrations and refractive conditions, corneal curvature, and axial length in schoolchildren with low myopia. Methods: This was a case series study. One hundred and eighty schoolchildren 8 to 13 years old, with a spherical equivalent (SE) of -0.50- -3.00 D, were recruited. Refractive error, calculated as the SE, axial length (AL), and corneal curvature radius (R, radius of the flat meridian—— R1, radius of the steep meridian—— R2) were measured by IOLMaster, and wavefront aberrations were measured by a WASCA Hartmann-Shack aberrometer. Multiple linear regression was used to analyze the factors influencing aberrations. Pearson correlation and Spearman correlation were used to investigate the correlation among myopia, structural parameters and aberrations. Results: Refractive errors and aberrations had no close correlation. Multiple linear regression analysis showed that total higher-order aberrations (RMSh) was significantly affected by corneal curvature and age (R2: B=-0.054, t=-2.986, P=0.003; Age: B=0.009, t=2.176, P=0.031). The curvature radius mainly affected fourth-order aberrations and age mainly affected third-order aberrations. AL was related to RMSh, fourth-order aberrations and spherical aberrations (r=-0.147, -0.333, -0.358, all P < 0.05). R1 and R2 were related to RMSh, fourth-order aberrations, and spherical aberrations too (R1: r=-0.249, -0.421, -0.435, all P < 0.001; R2: r=-0.260, -0.377, -0.392, all P < 0.001). AL/R was related to spherical error and SE (r=-0.490, -0.527, P < 0.001). Conclusions: The imaging quality of schoolchildren with low myopia may be influenced mainly by ocular structure rather than refractive condition. Key words: myopia; schoolchildren; aberrations; corneal curvature radius; axial length