Overnight orthokeratology (ortho-K) is a safe option for children with myopia, but a new study helps outline the risk factors for corneal adverse events when they do happen, including younger age, higher myopia and allergic conjunctivitis. The research, published in Contact Lens & Anterior Eye, included a retrospective medical record review of consecutive patients who were using ortho-K for myopia correction for more than one year. The study considered sex, baseline age and related medical histories of 489 eyes of 260 patients between the ages of eight and 15 who had a spherical equivalent refraction of -1.00D to -6.00D.

At the one-year follow-up, 22.7% of eyes had corneal adverse events, including corneal staining and corneal infiltration; overall, the incidence of significant adverse events was 6.9%.

The researchers found an association between corneal adverse events and age, spherical equivalent refraction and allergic conjunctivitis. Additionally, high refraction was the key risk factor for significant adverse events.