Choroidal Changes During and After Discontinuing Long-Term 0.01% Atropine Treatment for Myopia Control

Few studies have explored choroidal changes after cessation of myopia control. This study evaluated the choroidal thickness (ChT) and choroidal vascularity index (CVI) during and after discontinuing long-term low-concentration atropine eye drops use for myopia control.

Children with progressive myopia (6-16 years; n = 153) were randomized to receive 0.01% atropine eye drops or a placebo (2:1 ratio) instilled daily over 2 years, followed by a 1-year washout (no eye drop use). Optical coherence tomography imaging of the choroid was conducted at the baseline, 2-year (end of treatment phase), and 3-year (end of washout phase) visits. The main outcome measure was the subfoveal ChT. Secondary measures include the CVI.

During the treatment phase, the subfoveal choroids in both treatment and control groups thickened by 12-14 µm (group difference P = 0.56). During the washout phase, the subfoveal choroids in the placebo group continued to thicken by 6.6 µm (95% confidence interval [CI] = 1.7 to 11.6), but those in the atropine group did not change (estimate = -0.04 µm; 95% CI = -3.2 to 3.1). Participants with good axial eye growth control had greater choroidal thickening than the fast-progressors during the treatment phase regardless of the treatment group (P < 0.001), but choroidal thickening in the atropine group's fast-progressors was not sustained after stopping eye drops. CVI decreased in both groups during the treatment phase, but increased in the placebo group after treatment cessation.

On average, compared to placebo, 0.01% atropine eye drop treatment did not cause a differential rate of change in ChT during treatment, but abrupt cessation of long-term 0.01% atropine eye drops may disrupt normal choroidal thickening in children.