purpose : to evaluate the correlation of central corneal thickness (cct) with refractive error and keratometry in a group of patients eligible for laser keratorefractive surgery, which may serve as a bias in studies on intraocular pressure (iop) measurement methods : in a cross sectional observational study, the right eyes of 340 patients who underwent laser keratorefractive surgery during the ...

PURPOSE To explore the potential effect of ageing on the corneal curvature and corrected visual acuity in patients with long-term keratoconus because of the paucity of these patients older than 50 years. METHODS Records of keratoconic patients, who had initially presented to a specialized contact lens clinic and followed for more than 20 years after disease onset, were reviewed. Collected inf...

PURPOSE To study the intraocular pressure (IOP), the corneal thickness and the corneal curvature distribution in a normal population. To investigate the relation between these variables, and to determine if the IOP and the paquimetry will be modified by the refractive error and age. METHODS A population of 273 subjects, 545 eyes, without ocular pathology was selected. The refractive error, th...

OBJECTIVE Corneal topography and thickness has clinical importance in contact lens fitting and refractive surgery, however repeated measurement of corneal thickness and curvature is complicated by the natural phenomenon of diurnal variation. Our aim was determine diurnal variations of central and paracentral corneal thickness and curvature over a period of ten hours. MATERIALS AND METHODS Cor...

original article   to determine the association between ocular biometric components and near work in bank employees.this study was conducted as an analytical cross-sectional study. a group of bank employees and a control group were randomly selected. after applying the inclusion criteria, all selected subjects had a set of examinations including refraction, uncorrected and corrected visual acui...

INTRODUCTION Accurate corneal measurements are crucial in corneal refractive surgery (CRS) to ensure successful outcomes. Soft contact lens (SCL) wear may result in changes to corneal curvature and structure. United States Food and Drug Administration (FDA) pre-operative guidelines recommend that prior to CRS, SCL wearers cease SCL wear for "at least two weeks before examination and treatment" ...

Purpose To evaluate the accuracy of IOL power calculation using adjusted corneal power according to the posterior/anterior corneal curvature radii ratio. Methods Nine hundred twenty-eight eyes from 928 reference subjects and 158 eyes from 158 cataract patients who underwent phacoemulsification surgery were enrolled. Adjusted corneal power of cataract patients was calculated using the fictitio...

PURPOSE To quantify the error introduced by videokeratographic corneal topography devices in using a paraxial formula to calculate power over the entire corneal surface, including areas removed from the central paraxial region where the formula is known to be invalid. METHODS Corneal refractive power and two paraxial power approximations were computed as a function of distance from the apex f...