Comparative analysis of contrast sensitivity of adolescent orthokeratology lens wearers

Objective Adolescent myopia has a high incidence rate in China,and orthokeratology lens can improve the vision quality.This study focuses on the changes of contrast sensitivity(CS) in young patients wearing orthokeratology lens.MethodsWe included in this study sixty-four 7 to 20 years old patients with myopia in 120 eyes,who were all orthokeratology lens wearers.The diopter of the patients was ≤-6.00 D,and the best corrected visual acuity was ≥1.0.Based on diopter,the 120 eyes were divided into groups A(≤-2.00 D),B(-2.25 to-4.00 D) and C(-4.25 to-6.00 D).Another sixty 7 to 19 year-olds(120 eyes) with normal visual acuity(naked vision ≥1.0) were enlisted as controls.We performed the CS test for all the subjects and compared spatial frequencies among different groups as well as before and after orthokeratology lens wearing.Results Compared with the normal controls,the young myopia patients showed markedly reduced CS in all spatial frequency zones(P0.01),with statistically significant difference among the three diopter groups only in the intermediate frequency zone(P0.01).Orthokeratology lens wearing obviously improved CS,but with no significant difference as compared with different spatial frequencies(P0.05).Conclusion Adolescent myopia reduces CS in all spatial frequency zones.