Abstract
Purpose:
To investigate central retinal thickness in relation to axial length.
Methods:
The Copenhagen Child Cohort 2000 (CCC2000) is a population-based study where 1417 children have been examined with best corrected visual acuity, non-cycloplegic refraction, non-contact ocular biometry (IOL-master) and enhanced depth imaging spectral-domain optical coherence tomography (EDI-SD-OCT). Central retinal thickness (average thickness in the central 1000-μm diameter area) was calculated in 432 randomly selected children from the CCC2000 study. Scaling factors were as found in the instrument manufacturer's proprietary software.
Results:
Data from 432 children (199 boys; 233 girls) were analyzed. The mean age was 11.67 ± 0.33 years. All had a best corrected visual acuity of 50 letters on the ETDRS-chart or better and the mean axial length was 23.18 ± 0.76 mm. The mean spherical equivalent refraction was +0.12 ± 0.90 D. Mean central retinal thickness was 275.87 ± 19.03 μm. Boys had significantly longer eyes (0.42 mm, CI95 0.28 - 0.55 mm ; p < 0.001) and thicker central retinae (6.16 mm, CI95 2.59 - 9.72 μm ; p = 0.008) compared with girls (Student’s t-test analysis). Central retinal thickness increased 3.84 μm (CI95 0.88 - 8.23 μm ; p = 0.0019) per mm increase in axial length and was 4.55 μm (CI95 1.43 - 6.25 μm ; p < 0.0152) thicker in boys compared with girls in a multiple linear regression analysis including both sex and axial length. There was no significant interaction between sex and axial length.
Conclusions:
Central retinal thickness increased with increasing axial length and was thicker in boys than in girls in this subset of 432 children from a Danish population-based cohort of 1417 Danish children. The results are sensitive to errors of axial magnification scaling factors, especially those that vary with axial length.
Keywords: 551 imaging/image analysis: non-clinical •
605 myopia •
688 retina