Abstract
Purpose :
To determine the concentration of atropine with most tolerable side-effects by assessing the effect of three concentrations of atropine on pupil size and accommodative amplitude in children with myopia.
Methods :
Children with myopia (spherical equivalent, SE ≥ -0.50D with astigmatism ≤-2.00D) were randomly allocated to receive either 0.01%, 0.02% or 0.03% atropine eye drops, once nightly for two weeks. Primary outcomes were change from baseline for pupil diameter (mm) and accommodative amplitude (D). Photopic pupil size was measured with Oculus Park 1 (OCULUS Optikgerate GmBH, Wetzlar, Germany) with illuminance at eye of 350 lux. Accommodative amplitude was measured using the push-up method with the Royal Air Force (RAF) Ruler. The criteria for tolerable side effects were set at residual accommodative amplitude > 5D and change in photopic pupil size < 2mm. Comparison between study groups was performed using repeated measures Analysis of Variance (ANOVA). Statistical significance was set at p< 0.05.
Results :
Fifty-seven participants (mean age 9.26 ± 1.66 years, range 6 to 12 years old) with mean SE-3.53 ± 1.79D) completed the two-week trial. Baseline data of photopic pupil size (3.91 ± 0.63, 4.30 ± 0.79, 4.18 ± 0.84 mm) and accommodative amplitude (19.40 ± 1.72D, 19.75 ± 0.93D, 19.27 ± 1.74D), for 0.01%, 0.02% and 0.03%, respectively were not different between groups. After 2 weeks of atropine use, all the concentrations had a significant effect on the pupil diameter and accommodative amplitude (p<0.05). A reduction in accommodative amplitude and an increase in photopic pupil size were observed. Mean reduction in accommodative amplitude was 5.23 ± 4.11D, 9.28 ± 3.26 D and 9.32 ± 2.83D and mean increase in photopic pupil size was 0.95 ± 1.05 mm,1.65 ± 0.93 mm and. 2.16 ± 0.88 mm for 0.01%, 0.02% and 0.03% concentrations,respectively. Of the participants, 96.5% had residual accommodative amplitude > 5D with only two eyes in each group of 0.02% and 0.03% having the residual accommodation equal or less than 5D.
Conclusions :
All concentrations had an effect on pupillary size and accommodative amplitude in a dose-dependent manner. With atropine 0.01% and 0.02%, the side effects were tolerable. Since 0.01% was not effective in reducing axial length elongation, atropine 0.02% may be the highest tolerable concentration that could be considered for further investigations in myopia control.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.