Good Visual Performance Despite Reduced Optical Quality during the First Month of Orthokeratology Lens Wear. (2nd April 2020)

• Record Type: Journal Article
• Authors: Xia, Ruijing; Su, Binbin; Bi, Hua; Tang, Jiaze; Lin, Zhiyi; Zhang, Bin; Jiang, Jun
• Is Part Of: Current eye research. Volume 45:Number 4(2020)
• Page Start: 440
• Page End: 449
• Publication Date: 2020-04-02
• Subjects: RF pattern -- shape discrimination -- orthokeratology -- Fourier analysis -- corneal optical quality; Ophthalmology -- Periodicals; Eye -- Diseases -- Periodicals; Ophthalmology -- Periodicals; 573.88
• DOI: 10.1080/02713683.2019.1668950
• Languages: English
• ISSNs: 0271-3683

Abstract

ABSTRACT: Purpose : To measure changes in visual performances and optical quality in myopic children during the first month of wearing orthokeratology lens, and to reveal the association between those two. Methods : Thirty-five myopic children participated in this study. Visual performances were evaluated with visual acuity and shape discrimination threshold (SDT) for radial frequency patterns. Placido disc-based corneal topography for central 4 mm and 6 mm zones was collected and decomposed by Fourier analysis into the spherical, asymmetric, and regular astigmatic components. Root-mean-square of third-order, fourth-order, and total higher-order aberrations (HOA) were extracted for the 4 mm and 6 mm zones. All examinations were conducted at baseline, 1-week, and 1-month after lens dispensing. The changing trends over time and association between SDT and optical quality were analysed with linear-mixed model. Results : All subjects' uncorrected visual acuity improved to 0.1 logMAR or better at 1-week and 1-month lens wear ( P < .01). SDT did not change significantly from the baseline at 1-week and 1-month after lens wear ( P > .05). For the two zones with diameters of 4 mm and 6 mm, the spherical component decreased significantly at 1-week ( P < .01) and remained stable thereafter ( P < .01); the asymmetric component increased significantly at 1-week ( P < .01) and remained high at 1-month ( P < .01); and the regular astigmatism did not show any significant change throughout ( P > .05). At the two zones with diameters of 4 mm and 6 mm, the third-order, fourth-order, and total HOA increased significantly over time ( P < .05). Change of SDT did not correlate with impairments in optical quality ( P > .05 for all parameters). Conclusions : While corneal optical quality decreased steadily during the first month following lens wearing, the visual acuity and shape discrimination sensitivity assessed by SDT remained very satisfactory.