Purpose. To investigate the relationship between corneal biomechanical parameters, anterior segment parameters, and geometric corneal parameters in a healthy Caucasian group. Methods. This retrospective study included the healthy eyes with best corrected visual acuity of at least 20/40 of 122 Caucasian subjects. The anterior segment parameters and geometric corneal parameters such as corneal vo...

PURPOSE To investigate the changes in Goldmann applanation tonometry (GAT) and Ocular Response Analyzer (ORA) measurements with corneal edema induced by contact lenses. METHODS Twenty-five healthy, normal subjects (age, 23 ± 2 years) had central corneal radius (CCR), ORA, GAT, and central corneal thickness (CCT) measurements performed in both eyes before a thick, soft hydrogel contact lens wa...

Flat and spherical PMMA surfaces were ablated with a standard refractive surgery laser system. The ratio of profiles on flat to spherical PMMA surfaces was used to estimate experimentally the radial change in ablation efficiency for PMMA and cornea. Changes in ablation efficiency accounted for most of the asphericity increase found clinically, using the same laser system. This protocol is usefu...

Introduction In a broad review, evidence that the corneal biomechanical properties influence the results and outcomes of various ocular measurements and procedures has existed for some time [1,2]. However, assessing the biomechanical properties of corneal tissue in vivo has previously not been possible. With the recent introduction of the Reichert Ocular Response Analyzer (ORA), direct clinical...

Compound eyes of insects should be both thin and transparent to allow light pass through, at the same time mechanically stable serve as exoskeleton. These conflicting requirements make corneal cuticle an interesting example for studying biomechanics well designing composite materials that seek similar properties. Here, scanning electron microscopy, confocal laser nanoindentation are combined in...

Purpose To evaluate and compare corneal hysteresis (CH) and corneal resistance factor (CRF) in pellucid marginal degeneration (PMD), keratoconus (KCN), and normal eyes using the Ocular Response Analyzer (ORA). Methods In this retrospective study, corneal biomechanical parameters were measured in patients with PMD (n = 102) and KCN (n = 202) and normal subjects (n = 208) using the ORA. Data, i...

Purpose To investigate the effects of religious fasting during the month of Ramadan on intraocular pressure (IOP), refractive error, corneal tomography and biomechanics, ocular biometry, and tear film layer properties. Methods This prospective study was carried out one week before and in the last week of Ramadan. Ninety-four eyes of 94 healthy adult volunteers (54 males and 40 females) with a...