A 3-year study on the effect of RGP contact lenses on myopic children

Abstract

Aim and background: Recent studies in the West have shown that rigid gas-permeable (RGP) contact lenses can control the progress of myopia in children. These studies were done on Caucasian children, whose myopias are less rapidly progressive than those which we see in Singaporean children. This three-year study was started in 1993, with the following objectives: 1. To verify whether RGP contact lenses can control the progress of myopia in Singaporean children. 2. If so, to investigate the mechanism by which the lenses control myopia; whether by corneal flattening or by reducing the growth of the axial length. 3. If so, to assess if the effects are permanent, by discontinuing lens wear.

Materials and methods: The study was carried out at the Eye Clinic of the School Health Service. Enough school children were referred to the clinic from the various schools to achieve about 100 children wearing contact lenses. Past studies showed that the drop-out rate would be 50%, as there is no cosmetic motivation in 10 year-old children to wear contact lenses. The successful wearers were those who had parental encouragement and support.

Results: The results show that there was a suppression of the progress of myopia in children wearing the lenses as compared to their counterparts wearing spectacles. However, only in ten eyes was there arrest of the myopia. For the lenses to be effective, they needed to be worn regularly for about eight hours a day. Reasons for the drop-outs included lack of motivation, lens intolerance and simply being too busy with the school curriculum. Discontinuance of lens wear for more than 2 months had minimal effect on the refraction, indicating that the controlling effect was not due purely to corneal change.

Conclusion: It is recommended that more studies be done to confirm the findings of this study. Children with rapidly progressive myopia can wear rigid gas-permeable contact lenses to reduce the progression.