Abstract
Purpose :
A correlation between cone density and axial length has been shown in small studies. But association to birth parameters have not earlier been investigated.This cross-sectional study examined retinal cone density and its associations with birth parameters and axial length, gender and age in the Copenhagen Child Cohort (CCC2000) Study.
Methods :
The study included 1084 adolescents aged 16-17 (mean 16.6, SD ±0.29) years of Danish origin (470 male, 614 females) born in the Copenhagen County in the year 2000. Exclusion criteria were ocular pathology, being a twin, best corrected visual acuity < 80 ETDRS letters or previous eye trauma. Cone density and cone spacing was examined using adaptive optics fundus photography (RTX-1, Imagine Eyes). The images were measured using AO Detect mosaic software on images obtained 2 degrees temporal of the fovea. We tested for association between cone density and descriptive parameters including gestational age, birth weight, birth complications and maternal smoking during pregnancy, axial length, gender and age. Data were analyzed using multivariate regression analysis.
Results :
Mean cone density was 30030 cones/mm2 (SD ±3719, 95% CI 29803;30258, range 14765-39099) with no difference between genders. A longer axial length was associated with lower cone density of 2933 cones/mm2 per mm (P<0.001). A longer gestational age was associated with a slightly higher cone density of 119 cones/mm2 per week (P=0.0254). Adjusting for age and gender did not change the results. Cone density and cone spacing was highly correlated (R=-0.99, P<0.001). We found no association between cone density and any other descriptive parameters.
Conclusions :
Cone density in Danish 16-17-year-old adolescents was highly correlated to axial length, in agreement with smaller prior studies and the theory that the retina undergoes stretching during the development of myopia and that cone packing has been completed before the onset of myopic stretching.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.