Abstract
Purpose :
Peripheral refractive status plays a major role in central refractive development and therefore myopia progression. No systematic analysis of specific features of the peripheral refraction profiles and their influence on progression has been conducted on a large sample. We analyzed the contribution of curvature and slope (asymmetry) of peripheral refraction profiles, at baseline, to myopia progression prognosis in children.
Methods :
Unaided baseline peripheral refractive error data (Eyemapper, Brien Holden Vision Institute, Australia; NVision-K 5001, Shin-Nippon, Japan) from seven randomized clinical trials were analyzed. Data from 1186 Chinese children aged 10.8±1.7 (6-16 years) with 50% Males and 74% with at least 1 myopic parent were available. For each eye, relative (to central) peripheral refraction at the 20 degrees nasal and temporal visual fields was used to determine asymmetry, defined as the slope (D / degree) of a linear fit. Relative peripheral refraction between the nasal and temporal 30-degree fields was used to determine curvature, defined as the second order coefficient of a quadratic fit. Linear mixed model was used to determine the relationship of peripheral refraction profiles with annual progression after adjusting for confounders.
Results :
Study group (intervention worn) was the most significant factor associated with annual progression. This was followed by age at baseline, where progression reduced with increasing age (p<0.001). Slope and curvature were the third and fourth most significant factors (p<0.001 and p=0.006, respectively) ahead of parental myopia, gender and baseline spherical equivalent (p>0.05).
Conclusions :
Our data indicate that curvature and slope of the peripheral refractive error profile are good predictors of future progression. Overall, patients having high curvature (more relative peripheral hyperopia) and / or negative slope values (asymmetry with more hyperopic defocus in the temporal field) progressed slower than the other groups.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.