PURPOSE Astigmatism is a very common refractive error in humans, but its etiology is poorly understood. The primary purpose of this study was to determine whether alterations in visual experience would result in astigmatism in chicks. METHODS Longitudinal and cross-sectional data were obtained from chicks that were raised undergoing four different visual manipulations known to alter axial eye...

PURPOSE To assess visual performance and the effects of color overlays on reading in children who were deaf and children who could hear. METHODS Thirty-one children who were deaf (mean [± SD] age, 14 [± 1.99] years) and 39 children who could hear (mean [± SD] age, 13.58 [± 3.09] years) underwent an optometric examination with specific emphasis on near vision. Participants chose an overlay wit...

PURPOSE To evaluate the performance and potential clinical role of three-dimensional (3D) 1060-nm OCT by generating choroidal thickness (ChT) maps in patients of different ages with different degrees of ametropia and axial lengths and to investigate the effect of cataract grade on OCT retinal imaging quality. METHODS Axial lengths (ALs) and 45° fundus photographs were acquired from 64 eyes (3...

OBJECTIVE To determine the effect of the axial length of the eye on laser spot size and irradiance. DESIGN Experimental study using a calibrated Gullstrand-type model eye. METHODS The model eye, which was fitted with a scale of half circles in the center of the artificial fundus, was first examined using 2 different fundus imaging systems, then with a setup of a slitlamp, 2 indirect condens...

PURPOSE The aim of this analysis was to determine the total ocular wavefront aberration values of a large phakic population of physiologically normal, ametropic eyes, gathered under the same clinical protocol using the same diagnostic wavefront sensor. MATERIALS AND METHODS Studies were conducted at multiple sites in Asia, North America, Europe, and Australia. A Bausch + Lomb Zywave II Wavefr...

We determined effects of hemiretinal form deprivation (i.e., form-depriving half of the retina) on central refractive development and posterior eye shape in chicks. Seventy-seven White Leghorn chicks were randomly assigned to receive superior (SRD, "Superior Retinal Deprivation" or inferior visual field deprivation, same principle applies for the following abbreviations, n=17), inferior (IRD, n...