Abstract
Purpose :
Myopia has been associated with structural changes such as axial elongation and thinning of the retina and choroid. The relationship between choroidal thickness (CT), axial length (AL) and myopia has been studied in adult populations, however, there is little evidence available in children. Baseline data of 248 myopic children aged 6-16 years and enrolled in the Myopia Outcome Study of Atropine in Children (MOSAIC) clinical trial (ISRCTN36732601) were analysed to investigate the relationship between CT, AL and myopia in European children.
Methods :
Myopia was categorized into three subgroups: low myopia (<= -0.50 D to -3.00 D); moderate myopia (< -3.00 D to > -6.00 D); high myopia (<= -6.00D). Macular CT images were obtained using Triton Swept Source OCT; AL was measured with the Topcon Aladdin; cycloplegic spherical equivalent refraction (SER) was measured with the Grand Seiko Open Field autorefractor. Multiple linear regression analysis was used to explore associations between CT and age, gender, AL, and SER. A P-value of .05 was considered statistically significant.
Results :
The mean±SD age of participants was 11.3±2.4 years (63% females). There was a statistically significant difference in mean CT across the three myopic groups (P=.0002). A negative correlation between CT and AL was observed, with each additional millimeter in AL equating to a 21.2mm lower CT (P<.0001). There was a statistically significant positive correlation between CT and SER, with each additional diopter of myopia equating to a 11.5mm greater CT (P<.0001). Only AL was significantly associated with CT after adjusting for age, sex, and SER in the studied population. CT was thicker in females than in males (240.0mm vs 230.8mm; P=.29); thicker in younger (age 6-11) than older (age 12-16) children (242.9mm vs 229.5mm; P=.11).
Conclusions :
The current study showed that CT was thinnest in high myopes and was associated with AL in European children. The MOSAIC trial will evaluate longitudinal changes in CT in children with progressive myopia to understand the relationship between CT, AL and other ocular parameters both with (0.01% atropine treatment group) and without (placebo control group) myopia control treatment with low dose atropine.
This is a 2021 ARVO Annual Meeting abstract.