Abstract:AIM:To investigate the effect of peripheral defocus design rigid gas permeable contact lenses(defocus RGPCL)in controlling myopia progression in children aged 6-12 y with high myopia, and to compare the outcomes with traditional single-vision RGPCL and single-vision spectacles.
METHODS:This prospective cohort study enrolled children aged 6-12 y with high myopia who visited the Ophthalmology and Optometry Center of Xi'an No.1 Hospital between January 2022 and January 2023. Based on parental preference, participants were divided into three groups: defocused RGPCL group, single-vision RGPCL group, and single-vision spectacles group. The axial length(AL)and cycloplegic spherical equivalent(SE)refraction were compared at baseline, 0.5, 1, 1.5, and 2 y after lens wear. Additionally, AL and SE delay rates were calculated for each group.
RESULTS: This study enrolled a total of 90 children with high myopia(180 eyes), with no participants lost to follow-up. Participants were allocated into three groups based on parental preference. Thirty children(60 eyes)were assigned to the peripheral defocus RGPCL group, consisting of 12 boys and 18 girls with a mean age of 9.96±1.56 y; 30 children(60 eyes)to the single-vision RGPCL group, including 15 boys and 15 girls with a mean age of 9.40±1.52 y; and 30 children(60 eyes)to the single-vision spectacles group, with 14 boys and 16 girls and a mean age of 9.80±1.37 y. At 0.5, 1, 1.5, and 2 y lens fitting, AL and SE increased significantly in all three groups(all P<0.05), with the growth rates in the defocused RGPCL group being significantly lower than those in the single-vision RGPCL and single-vision spectacles groups(all P<0.05). At 2 y lens fitting, the AL elongation was 0.22±0.24 mm and the mean SE progression was 0.70±0.70 D in the peripheral defocus RGPCL group; 0.49±0.38 mm and 1.34±0.60 D in the single-vision RGPCL group; and 0.50±0.21 mm and 1.72±0.47 D in the single-vision spectacles group. Using the single-vision spectacles group as the control, the AL delay rate and SE delay rate at 2 y lens fitting were 56.0% and 59.3%, respectively, in the defocused RGPCL group.
CONCLUSION:For children with high myopia aged 6-12 y, defocus RGPCLs can effectively and significantly delay AL elongation and SE progression, demonstrating markedly superior control efficacy compared to single-vision RGPCL or single-vision spectacles. Defocused RGPCL can serve as an effective optical intervention for high myopia children.
