Axial Length/Corneal Radius of Curvature Ratio and Myopia in 3-Year-Old Children
Year: 2016
Type: article
Abstract: Purpose: This study investigated the association of axial length (AL) to corneal radius of curvature (CRC) ratio with spherical equivalent (SE) in a 3-year old Asian cohort. Methods: Three-hundred forty-nine 3-year old Asian children from The Growing Up in Singapore towards Healthy Outcomes (GUSTO) birth cohort study underwent AL and CRC measurements with a noncontact ocular biometer and cycloplegic refraction using an autorefractor. The ratio of AL to CRC (AL/CRC) was calculated for all the participants, and subsequently AL, CRC, and AL/CRC were analyzed in relationship to SE. Results: The SE showed better correlation with AL/CRC (Spearman's correlation coefficient, ρ = −0.53; 95% confidence interval [CI]: −0.66; −0.49; P < 0.001) compared to either AL or CRC alone ([ρ = −0.36; 95% CI: −0.51 to 0.51; P = 0.01] and [ρ = 0.05; 95% CI: −0.04 to 0.17; P = 0.34], respectively). Mean AL/CRC was 2.91 ± 0.06 among myopes and decreased to 2.79 ± 0.06 among hyperopes. Axial length to corneal radius of curvature was strongly correlated with SE in myopes (ρ = −0.78; 95% CI: −3.76; −0.79; P = < 0.001), but not in emmetropes and hyperopes ([ρ = −0.39; 95% CI: −10.73; −0.57; P = 0.01] and [ρ = −0.18; 95% CI: −17.28; 12.42; P = 0.38], respectively). Linear regression adjusted for gender and ethnicity showed a 0.74-diopter shift in SE towards myopia with every 0.1 increase in AL/CRC ratio (P < 0.001, r2 = 0.33). Conclusion: The correlation between SE and AL/CRC is stronger than that between AL or CRC alone. This suggests that in a research setting, when cycloplegic refraction is difficult to perform on 3-year-old children, AL/CRC may be the next best reference for refractive error. Translational Relevance: In the research setting, AL/CRC may be the next best reference for refractive error over AL alone when cycloplegic refraction is unavailable in 3-year old children.
DOI: 10.1167/tvst.5.1.5
Institutions: National University of Singapore, Singapore National Eye Center, Singapore Eye Research Institute, National University Hospital, National University Health System, Agency for Science, Technology and Research, Singapore Institute for Clinical Sciences, KK Women's and Children's Hospital, University of Auckland
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $1,850
OpenAlex ID: W2327265064