AI Article Synopsis
- The study aimed to investigate how photopic pupil size (PPD) changes in myopic children undergoing overnight orthokeratology (ortho-k) and how this affects their eye growth over a year.
- A total of 202 Chinese myopic children participated, with those in the ortho-k group showing slower axial elongation compared to the spectacle group (0.25 mm vs. 0.44 mm).
- Results suggested that smaller PPD (specifically ≤4.81 mm) correlated with less axial elongation, indicating that children with smaller pupil sizes may benefit more from ortho-k treatment in terms of eye growth.
Article Abstract
Aim: To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology (ortho-k) over 1-year period and its effects on the axial elongation.
Methods: A total of 202 Chinese myopic children were enrolled in this prospective clinical trial. Ninety-five subjects in ortho-k group and eighty-eight subjects in spectacle group completed the 1-year study. Axial length (AL) was measured before enrollment and every 6mo after the start of ortho-k. The photopic pupil diameter (PPD) was determined using the Pentacam AXL and measured in an examination room with lighting of 300-310 Lx. Stepwise multiple linear regression analysis was used to identify variables contribution to axial elongation.
Results: Compared with spectacle group, the average 1-year axial elongation was significantly slower in the ortho-k group (0.25±0.27 0.44±0.23 mm, <0.0001). In ortho-k group, PPDs significantly decreased from 4.21±0.62 mm to 3.94±0.53 mm after 1mo of lens wear (=0.001, Bonferroni correction) and the change lasts for 3-month visit. No significantly change during the other follow-up visits was found (>0.05, Bonferroni correction). The 4.81 mm PPD may be a possible cutoff point in the ortho-k group. Subjects with PPD below or equal to 4.81 mm tended to have smaller axial elongation compared to subjects with PPD above 4.81 mm after 1-year period (=-3.09, =0.003). In ortho-k group, univariate analyses indicated that those with older age, greater degree of myopia, longer AL, smaller baseline PPD (PPD) experienced a smaller change in AL. In multivariate analyses, older age, greater AL and smaller PPD were associated with smaller increases in AL. In spectacle group, PPD tended to be stable (>0.05, Bonferroni correction) and did not affect axial growth.
Conclusion: PPDs experience significantly decreases at 1-month and 3-month ortho-k treatment. Children with smaller PPD tend to experience slower axial elongation and may benefit more from ortho-k.
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Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9358181 | PMC |
| http://dx.doi.org/10.18240/ijo.2022.08.15 | DOI Listing |
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