Purchase this article with an account.
J.M. Jackson, T. Bildstein, J. Anderson, B. Leak, K. Buresh; Short–Term Corneal Changes with Corneal Refractive Therapy (CRT) . Invest. Ophthalmol. Vis. Sci. 2004;45(13):1547.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: To evaluate changes in visual acuity, corneal topography, and corneal thickness after short periods of CRT lens wear. Methods: Twenty eyes of 10 subjects were analyzed. One eye was randomly selected to wear the CRT lens, while the other served as a control. After baseline examination, the test eye was fit with the CRT lens. Subjects wore the lens for intervals of 10 minutes, 30 minutes, and 60 minutes. After each period, the lens was removed and a masked examiner measured unaided high contrast LogMAR VA, corneal topography (Humphrey Atlas), and ultrasound pachymetry (Corneogage II) for both eyes. The results were compared to the same values measured at the baseline examination prior to lens wear using repeated–measures ANOVA. Results: Visual acuity improved in the test eyes (p<0.001, ANOVA) after 30 minutes (0.2 +/– 0.02 LogMAR mean improvement), but did not change over time in the control eyes (p=0.48, ANOVA). Apical corneal radius flattened significantly in the test eyes (p<0.001, ANOVA) after 10 minutes (0.05 +/– 0.02 mm mean change), but did not change in the control eyes (p=0.979, ANOVA). Total central corneal thickness did not change significantly in either group (p=0.021 test eyes; p=0.053 control eyes, ANOVA). Central epithelial thickness did not change significantly in either group (p=0.242, test eyes; p=0.624, control eyes, ANOVA). Conclusions: Previous studies using other orthokeratology lens designs have found significant changes in acuity, topography, and corneal thickness after 10 minutes of lens wear. This study, using the CRT design, shows similar results, but acuity changes took longer to achieve and pachymetry changes did not occur. The lack of corneal thickness changes may be attributable to the ultrasound instrument used for this study.
This PDF is available to Subscribers Only