The associations of accommodation and aberrations in myopia control with orthokeratology

Abstract

This study aimed to investigate the effect of orthokeratology (OK) on accommodative function and aberrations, to explore the correlations between them and determine what role they play in myopia control. Methods:In this prospective case-controlled study, 61 children were divided into an OK (n = 30) and a single-vision spectacles (SVS) (n = 31) group. Accommodation and ocular wavefront aberrations in the OK group were measured at baseline and after 1, 3, 6, 9 and 12 months of OK wear, and again at 1 month after stopping OK (13 th month). The same procedure was performed in the SVS group at baseline and at 3, 6 and 12 months. Axial length (AL), accommodative lag area and aberrations including spherical aberration (SA), coma and total higher-order aberrations (HOAs) were analysed.Results: During OK wear, the accommodative lag area at each visit was lower than the baseline level (all p < 0.01); all aberrations at each visit were higher than pretreatment (all p < 0.001). After 1 month of OK treatment, changes in accommodative lag area and SA did not show significant correlation (p = 0.16), but after OK cessation these changes were correlated (p = 0.01). In the OK group, multivariate regression analysis showed changes in accommodative lag area were associated with AL progression in the first 6 months but not in the 1-year analysis. For the SVS group, there were no significant changes in the accommodative lag area or any aberrations during the study period.Conclusions: Increased HOAs and improved accommodative accuracy were observed during OK treatment, but began to regress after the cessation of OK. A significant positive correlation between improved accommodative accuracy and slowed axial elongation was only observed during the first 6 months of treatment.

IMI 2023 Digest

“… 228 – 230 New data on ortho-k propensity to increase the accommodation response 231 , 232 and create an exophoric shift in children at near 232 are in agreement with results from previous studies 233 , 234 and appear linked to a greater myopia control. 231 In contrast, aspheric MFSCLs were found to reduce the accommodation response and yet induce a small exophoric shift in children 235 , 236 and young adults, 228 , 237 , 230 , 237 with different peripheral add powers having no differential impact on these responses. 228 , 230 For ortho-k, a more accurate accommodation response has been correlated with a larger myopia control effect.…”

Orthokeratology with increased compression factor in adolescent myopia control: a 2-year prospective randomized clinical trial

“…Recent studies investigated that children with higher levels of HOAs in the root-mean-square (RMS) values exhibited slower axial growth [20][21][22] . As the corneal shape is modified during ortho-k treatment, ocular aberrations, primarily HOAs, significantly increase [23][24][25] . The increase in HOAs may usually be asymmetric.…”

Night contact lenses used for myopia – personal experience

“…Another study showed that night contact lenses have a beneficial effect on accommodative function during the treatment and there was a significant association between improved accommodative accuracy and decreased axial elongation during the first six months of therapy [ 25 ].…”