Effects of 0.01% atropine on ocular biometrics in myopic adolescents

To observe the effects of 0.01% atropine eye drops on ocular biometrics in myopic adolescents.

A prospective cohort study was conducted.Two hundred and nineteen myopic adolescents who visited the First Affiliated Hospital of Zhengzhou University from June 2016 to June 2017 and completed the 1-year follow-up on time were enrolled.The 219 adolescents were divided into a 0.01% atropine+ single-vision spectacles (SV) group (119 cases) wearing single-vision spectacles with one drop of atropine eye drop applied to both eyes once nightly, and a simple SV group (100 cases) wearing SV only.Axial length (AL), corneal power and anterior chamber depth were measured with the IOLMaster.Lens power was calculated using the Bennett-Rabbetts formula.Intraocular pressure was measured by non-contact tonometry.Spherical equivalent (SE) was examined by cycloplegic autorefraction.Total astigmatism and corneal astigmatism were calculated by vector decomposition.The right eye data were analyzed to compare the ocular biometrics changes between the two groups, and multiple linear regression analysis was used to evaluate the influencing factors.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of First Affiliated Hospital of Zhengzhou University (No.2016-35). Written informed consent was obtained from guardians before any medical examination.

The SE change and AL elongation 12 months after treatment in 0.01% atropine+ SV group were (-0.47±0.45) D and (0.37±0.22) mm, respectively, which were significantly lower than (-0.70±0.60)D and (0.46±0.35)mm in simple SV group (t=5.523, 9.651; both at P<0.001). There were significant differences in SE and AL between before and after treatment in both groups (SE: F_group=1.556, P=0.015; F_time=12.538, P=0.002; AL: F_group=3.425, P=0.021; F_time=18.235, P=0.008). The SE and AL at 4, 8 and 12 months after treatment were all increased in comparison with before treatment in both groups, showing statistically significant differences (all at P<0.001). The SE and AL at 8 and 12 months after treatment in 0.01% atropine+ SV group were smaller than in simple SV group, and the differences were statistically significant (all at P<0.001). At 8 and 12 months after treatment, total astigmatism and the anterior chamber depth were increased and the lens power was decreased in comparison with before treatment in both groups, and the differences were statistically significant (all at P<0.05). There was no significant difference in corneal astigmatism, corneal power and intraocular pressure at different time points before and after treatment between the two groups (all at P>0.05). In the multiple linear regression analysis, an equation of Δmyopic SE=-0.012-2.685×ΔAL-1.002×Δcorneal astigmatism-0.656×Δlens power+ 0.477×Δtotal astigmatism+ 0.363×Δanterior chamber depth-0.060×age+ 0.011×sex was used, showing the change of SE was mainly caused by the change of AL (β=-2.685), then corneal power, lens power, total astigmatism and anterior chamber depth.

In adolescents, 0.01% atropine eye drops can effectively retard myopia progression and axial elongation, showing no effect on astigmatism, corneal power, lens power, anterior chamber depth and intraocular pressure.The controlling effect of 0.01% atropine eye drops in the development of myopia is mainly achieved by reducing axial elongation.