Abstract
Purpose
To determine the intensity of corneal pigmented arc in orthokeratology (ortho-k)-treated children, and its correlation with key epithelial thickness measurements obtained by anterior segment optical coherence tomography (AS-OCT).
Methods
This study is a retrospective case series. Medical records of children who received ortho-k treatment for myopia control in our hospital were reviewed. Intensity of ortho-k-associated pigmented arc and its correlation with key epithelial thickness parameters in the central 7-mm-diameter zone obtained by AS-OCT was examined. The subjects were further divided into apparent and unapparent pigmented arc groups for severity comparison.
Results
The mean age of children was 11.4 years, and the incidence of corneal pigmented arc was 92.2% after lens wear for a mean duration of 21.2 months. Intensity of pigmented arc was found to be significantly correlated with key epithelial thickness parameters, including maximum and minimum epithelial thickness (Spearman’s rank correlation coefficient (rs) = 0.404, P = 0.003; rs = − 0.426, P = 0.002, respectively), the difference between them (Min–Max) (rs = −0.624, P < 0.001) and standard deviation (rs = 0.659, P < 0.001). Significant correlation between intensity of pigmented arc and ortho-k target power (rs = 0.454, P = 0.001) was found. Comparison between the two groups showed significant difference in the same key epithelial thickness parameters.
Conclusions
Children receiving ortho-k treatment tended to develop pigmented arcs. Significant correlation between intensity of pigmented arc and key epithelial thickness parameters was observed. AS-OCT can be a useful tool for predicting intensity of pigmented arc in ortho-k-treated children.
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Acknowledgements
We acknowledge the financial support of the Maintenance Project of the Bio-statistical Consultation Center under Grant CLRPG2G0082 and thank the technicians of the Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung for their technical assistance.
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Liu, CF., Lee, JS., Sun, CC. et al. Correlation between pigmented arc and epithelial thickness (COPE) study in orthokeratology-treated patients using OCT measurements. Eye 34, 352–359 (2020). https://doi.org/10.1038/s41433-019-0542-8
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DOI: https://doi.org/10.1038/s41433-019-0542-8
