Effect of Low-dose Atropine on Binocular Vision and Accommodation in Children Aged 6 to 17 Years

SIGNIFICANCE Low-dose atropine is one of the leading treatments of myopia progression in children. However, the effect of low-dose atropine on binocular vision measurements has not been thoroughly studied. PURPOSE This study aimed to determine the effect of 0.01, 0.03, and 0.05% atropine on visual acuity, pupil size, binocular vision, and accommodation in children aged 6 to 17 years. METHODS Forty-six children (28 girls and 18 boys) were randomized into four groups: placebo (n = 10) and 0.01% (n = 13), 0.03% (n = 11), and 0.05% (n = 12) atropine. One drop of atropine or placebo was administered into each eye once. The following measurements were collected before applying the eye drops and 30 minutes, 60 minutes, and 24 hours after application of eye drops: habitual visual acuity at distance and near, pupil size, dissociated phoria at distance and near, negative and positive fusional vergence, near point convergence, near point convergence stamina and fragility, accommodative lag, and amplitude of accommodation. Repeated-measures analysis of variance was used, and P < .05 was considered statistically significant. RESULTS Differences in pupil diameters under photopic and scotopic conditions were statistically significant when comparing all three atropine groups with placebo over time ( P < .001). Pupil size in both the 0.03 and 0.05% atropine groups was enlarged from baseline at the 30-minute, 60-minute, and 24-hour time points ( P < .05) in both photopic and scotopic conditions. Pupil size in the 0.01% atropine group had minimal change, and only the scotopic 60-minute time point was statistically significant ( P = .02). All three concentrations of atropine eye drops have no significant effect on accommodation, binocular vision measurements, or visual acuity compared with the control group. CONCLUSIONS Pupil size was significantly enlarged by 0.03 and 0.05% atropine in both photopic and scotopic conditions. Low-dose atropine eye drops have no significant effect on accommodation, binocular vision measurements, or visual acuity compared with control.