Short-term refractive and ocular parameter changes after topical atropine

PURPOSE: The purpose of this study is to explore short-term refractive and ocular parameter changes and their correlations after cycloplegia with atropine. METERIALS AND METHODS: This is a prospective clinical trial that enrolled 96 eyes of 96 participants (mean age, 8.5 ± 2.1 years). Spherical equivalent refractive error (SER), axial length (AL), mean keratometric value (mean-K), anterior chamber depth (ACD), and intraocular pressure (IOP) were measured at baseline and 1 week after topical use of 0.125% atropine. Postcycloplegic changes of refractive error and ocular parameters were evaluated, and their correlations were analyzed with multiple linear regression models. RESULTS: After topical atropine use, the mean AL decreased by 0.016 mm (P = 0.008), and the mean ACD increased by 0.58 mm (P < 0.0001). There was no significant change in the Mean-K or IOP. Eighty-two eyes (85%) had an emmetropic or hyperopic shift, and 14 (15%) had a myopic shift. Those with an emmetropic or hyperopic shift had their mean AL shortened by 0.023 mm, whereas the eyes with myopic shifts had their mean AL lengthened by 0.026 mm (P = 0.003). Change in SER was negatively correlated with change in AL (−2.57 D for an increase of 1 mm in AL, P < 0.001) and positively correlated with change in ACD (+0.96 D for an increase of 1 mm in ACD, P = 0.013). CONCLUSION: Most eyes had emmetropic or hyperopic changes after short-term topical atropine use, and AL shortening and anterior chamber deepening both contributed to the hyperopic changes. Meanwhile, myopic change may be observed in some eyes (15%), which were related to transient AL elongation but not invalid myopic control. This encouraged clinicians to sustain the atropine treatment for a longer period before switching to other modalities for myopic control in clinical practice. The clinical trial registration number NCT03839888 (clinicaltrials.gov).