Combination of orthokeratology and low-dose atropine for axial length elongation control in myopic children with a poor response to orthokeratology

Objectives To compare the effectiveness of combined treatment comprising low-dose atropine and orthokeratology (OK) in controlling myopia in children with poor responses to OK. Methods This retrospective study evaluated 91 children who underwent two years of OK treatment. All the children were 6–12 years old at the start of OK treatment. They all showed a minimum annual increase of 0.3 mm in the first year. In the second year, children receiving 0.01% atropine were categorized into the OKA 0.01% group, those receiving 0.05% atropine into the OKA 0.05% group, and those not receiving atropine into the Mono-OK group. Results In the end of the first year, the axial length (AL) in the OKA 0.01% and Mono-OK groups were similar (25.01 mm and 25.29 mm, P  = 0.160). However, the OKA 0.05% group exhibited a shorter AL (24.54 mm) than both the OKA 0.01% and Mono-OK groups ( P  = 0.013 and P <  0.001). After atropine combination therapy, the OKA 0.05% group also exhibited a smaller AL change (0.02 mm/y) than did the Mono-OK group (0.38 mm/y; P  < 0.001) and OKA 0.01% group (0.27 mm/y; P = 0.002 ), while the difference between the OKA 0.01% and Mono-OK groups was not significant (0.27 mm/y vs. 0.38 mm/y; P  = 0.192). Conclusions For young children with a poor response to OK, the addition of 0.05% atropine could control the progression of axial elongation compared with the combination of 0.01% atropine.