Research Article Responses of the Ocular Anterior Segment and Refraction to 0.5 % Tropicamide in Chinese School-Aged

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Purpose. To investigate the changes of anterior segment after cycloplegia and estimate the association of such changes with the changes of refraction in Chinese school-aged children ofmyopia, emmetropia, and hyperopia.Methods. 309 childrenwere recruited and eligible subjects were assigned to three groups: hyperopia, emmetropia, or myopia. Cycloplegia was achieved with five cycles of 0.5 % tropicamide. The Pentacam system was used to measure the parameters of interest before and after cycloplegia. Results. In the myopic group, the lenses were thinner and the lens position was significantly more posterior than that of the emmetropic and hyperopic groups in the cycloplegic status.The correlations between refraction and lens thickness (age adjusted