Comparative Evaluation of the Efficacy, Safety, and Corneal Dynamics of Overnight Orthokeratology in Teenagers and Adults With Myopia: A Prospective, Open-Label Study in Taiwan.

BACKGROUND: Myopia is a global public health concern, and its prevalence has been increasing year by year worldwide. Orthokeratology uses gas-permeable contact lenses to reshape the corneal contour and correct low-to-moderate myopia. Orthokeratology has also been shown to reduce myopia progression in children. For adults, ortho-K lenses remain a viable option for myopia correction; however, their usage rate is relatively low due to maintenance difficulties and safety concerns. To date, few studies have compared the efficacy, safety, and corneal dynamics of ortho-K use between teenagers and adults. METHODS: Subjects with myopia of either sex aged between 12 and 65 years were enrolled in this prospective open-label study. The subjects were fitted with Progressive Boston Orthokeratology Shaping Lenses for overnight wear and were instructed to wear (before going to sleep) the lenses for > 7 h each night and remove them in the morning, for 9 months. Manifest refraction spherical equivalent (MRSE) and uncorrected visual acuity (UCVA) were assessed. RESULTS: Overall, 68 subjects (134 eyes) completed the study, and of these, 15 (22.06%) subjects were teenagers (≤ 19 years) and 53 (77.94%) subjects were adults (> 19 years). In the teenager and adult groups, the mean MRSE changed from -2.84 D and -3.31 D at baseline to approximately 0.0 D in both groups at 9 months. UCVA improved significantly in both groups, reaching approximately Snellen 20/20 (logMAR 0) within the first few weeks of treatment and remaining stable throughout the study period. No clinically significant increases in intraocular pressure were observed during treatment, and endothelial cell density remained clinically stable. Mild corneal staining occurred in a small number of examinations and resolved with conservative management. After discontinuation, both MRSE and UCVA in both groups quickly returned to baseline by Week 4. CONCLUSION: These findings suggest that orthokeratology is an effective option for temporary correction of low-to-moderate myopia in both teenagers and adults. Within the limitations of the sample size, orthokeratology may be considered a safe and effective myopia correction option for adults.