Toric orthokeratology for highly astigmatic children

Purpose. To determine the efficacy of toric orthokeratology (ortho-k) in correcting myopia and astigmatism in myopic children with moderate to high astigmatism. Methods. Asymptomatic subjects aged 6 to 12 years with myopia of 0.50 to 5.00 D and astigmatism of 1.25 to 3.50 D of axes 180 ± 20° were fitted with Menicon Z Night Toric Lens (NKL Contactlenzen B.V., Emmen, The Netherlands). Data collection was performed at baseline and 1 night, 1 week, and 1 month after the commencement of lens wear. The results from the right eye or the eye with higher astigmatism were reported. Results. The first lens fit success rate was 95%. Two subjects had to be refitted due to lens decentration and inadequate central clearance after one overnight lens wear and were successfully fitted with a second pair of lenses. Toric ortho-k significantly reduced the manifest myopia from 2.53 ± 1.31 D to 0.41 ± 0.43 D and astigmatism from 1.91 ± 0.64 D to 0.40 ± 0.39 D (paired t-tests, p < 0.02) after 1 month of lens wear. The unaided visual acuity (logMAR) was 0.11 ± 0.13 after 1 month of lens wear. No significant lens binding, corneal staining, or other adverse events were observed during this period of lens wear. Conclusions. This toric lens design lens, with a first lens fit success rate of 95%, was effective in correcting low-moderate myopic children who had moderate-high astigmatism. It has the potential to be used in myopic control studies for myopic children who have high astigmatism.