Abstract
Purpose: :
Investigations that indicate soft contact lenses induce myopia progression ("myopic creep") all last one year or less. The purpose of this investigation is to measure the refractive error, corneal curvature, and axial length of eight to 11 year old children randomly assigned to wear single vision glasses or soft contact lenses (Acuvue 2 or 1 Day Acuvue, Vistakon) for three years to compare the rate of myopic progression with each mode of correction over three years as part of the ACHIEVE Study.
Methods: :
Measurements were conducted prior to randomization and annually. Cycloplegic autorefraction, following one drop of 0.5% proparacaine and two drops of 1.0% tropicamide, and the curvatures of the flat and steep corneal meridians were obtained by the Grand Seiko WR-5100K (Grand Seiko Co., Ltd., Fukuyama, Japan). The Sonomed A-5500 A-Scan (Sonomed, Inc., Lake Success, NY) was used to measure the axial length using a hand-held probe.
Results: :
We enrolled 484 subjects; 237 assigned to glasses and 247 assigned to contact lenses. We examined 467 (96.5%) of the subjects at the final visit. The spectacle wearers progressed -1.08 ± 0.71 D, and the contact lens wearers progressed -1.27 ± 0.72 D (analysis of covariance, p = 0.005). The axial growth of the spectacle wearers was 0.59 ± 0.37 mm and 0.63 ± 0.34 mm for the contact lens wearers (analysis of covariance, p = 0.27). The change in the steep corneal meridian was 0.05 ± 0.69 D for the spectacle wearers and 0.10 ± 0.70 D for the contact lens wearers (analysis of covariance, p = 0.43).
Conclusions: :
Although the three-year myopic progression is statistically greater in contact lens wearers than spectacles wearers, the difference is only 0.19 D, which is not clinically meaningful. Additionally, there was no difference in the axial growth of the eyes between the two groups. Soft contact lens wear was not shown to increase the rate of myopia progression in children over a three year period.
Clinical Trial: :
www.clinicaltrials.gov NCT00522288
Keywords: contact lens • myopia • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials