Long-term follow-up of changes in ocular biometric parameters in orthokeratology lens wearers with relatively large-scale axial length reduction

Abstract Background To investigate ocular biological characteristics for myopic children with axial length (AL) reduction during orthokeratology (Ortho-K) treatment and provide clinical clues for better myopia control effects. Methods Changes in ocular parameters and treatment zone (TZ) in 75 subjects who completed one-year Ortho-K treatment were retrospectively reviewed. The subjects were divided into two groups according to one-year AL change: the AL reduction group (n = 37) and the AL elongation group (n = 38). Univariate and multivariate regression analyses were performed to determine the association between TZ, ocular parameters, and AL change. Results There was no significant difference in baseline between the two groups (all P > 0.05). After one year of Ortho-K treatment, compared with those in the AL elongation group, children in the AL reduction group had a decreased anterior chamber depth (ACD) (P