The Effects of Low Dose Atropine on Choroidal Thickness

Summary

Atropine eye drops are considered to be an effective form of myopia control in human eyes. However, the mechanism by which it exerts it effects are not fully understood. Thickening of the choroid subsequent to atropine administration may play an important role in the mechanisms by which atropine induces myopia control. Literature also notes that choroidal thickness undergoes diurnal variations, which is a variable that will be controlled in this study in order to examine atropine's effects on different baseline choroidal thicknesses. The purpose of the proposed study is to characterize better the influence of atropine on choroid thickness. The study aims are to: 1. Determine the effect of low dose concentration of topical atropine (0.1% and 0.01%) on choroid thickness 2. Determine the effect of topical atropine on choroid thickness in relationship to baseline thickness throughout the day and after one week of daily instillation Hypothesis: Atropine's effect on choroidal thickness will be dependent on the subject's baseline thickness measurements, at a designated time of the day when the choroid is at its thinnest.

Timeline

Start

2018-05-21

Primary completion

2019-02-08

Completion

2019-02-08

Publications

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• Background Chakraborty R, Read SA, Collins MJ. Diurnal variations in axial length, choroidal thickness, intraocular pressure, and ocular biometrics. Invest Ophthalmol Vis Sci. 2011 Jul 11;52(8):5121-9. doi: 10.1167/iovs.11-7364.
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• Background Gong Q, Janowski M, Luo M, Wei H, Chen B, Yang G, Liu L. Efficacy and Adverse Effects of Atropine in Childhood Myopia: A Meta-analysis. JAMA Ophthalmol. 2017 Jun 1;135(6):624-630. doi: 10.1001/jamaophthalmol.2017.1091.
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• Background McAlinden C, Pesudovs K, Moore JE. The development of an instrument to measure quality of vision: the Quality of Vision (QoV) questionnaire. Invest Ophthalmol Vis Sci. 2010 Nov;51(11):5537-45. doi: 10.1167/iovs.10-5341. Epub 2010 May 26.
• Background Rahman W, Chen FK, Yeoh J, Patel P, Tufail A, Da Cruz L. Repeatability of manual subfoveal choroidal thickness measurements in healthy subjects using the technique of enhanced depth imaging optical coherence tomography. Invest Ophthalmol Vis Sci. 2011 Apr 8;52(5):2267-71. doi: 10.1167/iovs.10-6024. Print 2011 Apr.

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