Changes in choroidal thickness and blood flow in myopic children with 0.01% atropine or orthokeratology and atropine combination therapy

PURPOSE: To evaluate changes in choroidal thickness (CT), choroidal blood flow and axial length (AL) after therapy with either 0.01% atropine eye drops (AT) or the combination of orthokeratology and 0.01% AT (OKA) among Japanese myopic children. METHODS: We analysed changes in CT, choroidal blood flow and AL among myopic children who received either 0.01% AT or the OKA therapy at Toho University Omori Hospital from January 2021 through December 2022 (n = 38 eyes, 8.26 ± 2.13 years old in the 0.01% AT group and n = 44 eyes, 8.36 ± 1.54 years old in the OKA group). Comprehensive ophthalmologic examinations were performed at baseline, 3, 6 and 12 months. RESULTS: Subfoveal CT increased in the OKA group more than that in the AT group at 3, 6 and 12 months. Choroidal blood flow increase was greater in the OKA group compared to that in the AT group at 6 and 12 months. AL increase was less in the OKA group than that in the AT group at 6 and 12 months. AL changes were negatively correlated with choroidal blood flow and CT changes at both time points. In multivariate analysis, age, male, CT change and choroidal blood flow were independently associated with AL changes at 12 months. CONCLUSION: The increase in CT was more pronounced in the combination therapy group compared to the AT group. The increase in CT and choroidal blood flow was associated with a reduced AL progression.