A Meta-analysis of Central Corneal Thickness Changes With Overnight Orthokeratology

Abstract

Objectives: To assess the change of central corneal thickness (CCT) in the treatment of orthokeratology in patients with myopia.

Methods: A systematic search of all relevant studies published through April 2014 was conducted, and 95% confidence intervals (CI) of CCT change were calculated. Random or fixed-effects models were used according to heterogeneity. Publication bias of the articles was evaluated using funnel plots and Begg test.

Results: A total of 10 studies with 239 patients (339 eyes) from clinical studies were included. Central corneal thickness reduced significantly from 1 day to 1 week by 5.73 μm (95% CI, 1.75-9.70 μm; P=0.005), and a significant mean reduction of 5.89 μm also occurred from 1 day to 1 month (95% CI, 3.50-8.29 μm; P<0.001). No significant reduction was found between 1 week and 1 month (P=0.32).

Conclusions: Our meta-analysis demonstrated that most reduction of CCT occurred during the first week and remained thinner for 1 month. Further randomized controlled trials with larger sample sizes, standardized outcome measurements, and different follow-up periods are warranted to find the precise change.