The safety of orthokeratology in myopic children and analysis of related factors.

<bold>Objective: </bold>To evaluate the safety of overnight orthokeratology (OK) wear and explore whether factors such as age, refraction and allergic conjunctivitis (AC) history were associated with corneal adverse events (AEs) incidence.<bold>Methods: </bold>Medical records of consecutive patients who started OK for myopia correction and continued for more than one year were retrospectively reviewed. Clinical data including sex, baseline age, spherical equivalent refraction (SER), and related medical histories were retrieved. A total of 489 eyes from 260 patients (age: 8-15 years; SER: -1.00 to -6.00 D) were included. Corneal adverse events were the primary outcome. The generalized estimating equations model was used to evaluate the effects of sex, age, SER, and allergic conjunctivitis history on corneal AE incidence over the one-year period.<bold>Results: </bold>A total of 111 eyes (22.7%) had corneal AE during the one-year follow-up (corneal staining [n = 106], corneal infiltration [n = 5]) and the incidence of significant AE was 6.9%. The corneal AE incidence was associated with age (OR = 0.874, 95%CI = 0.781-0.978, p = 0.019); SER (OR=0.632, 95%CI=0.531-0.754, p < 0.001); and AC (OR=1.706, 95%CI=1.017-2.860, p = 0.043). High refraction was the key risk factor for significant AE (OR=0.542, 95%CI=0.401-0.732, p < 0.001).<bold>Conclusions: </bold>Orthokeratology is a safe option for children with myopia. Younger age, higher myopia, and AC were risk factors for corneal AE in OK wearers. Whereas, only higher myopia was a risk factor for significant AE. [ABSTRACT FROM AUTHOR]