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...

PURPOSE We evaluated ocular optical components and their interrelationships in myopic Korean patients. METHODS In this prospective observational study, 1,011 consecutive patients were recruited from a refractive surgery clinic. The best-corrected visual acuity was >20 / 20 in all patients. The refractive error, axial length (AL), anterior chamber depth (ACD), lens thickness (LT), and vitreous...

PURPOSE To determine corneal Q value and its related factors in Chinese subjects older than 30 years. DESIGN Cross sectional study. METHODS 1,683 participants (1,683 eyes) from the Handan Eye Study were involved, including 955 female and 728 male with average age of 53.64 years old (range from 30 to 107 years). The corneal Q values of anterior and posterior surfaces were measured at 3.0, 5....

PURPOSE To produce a two-dimensional reconstruction map of the living corneal sub-basal nerve plexus in keratoconus with in vivo confocal microscopy. METHODS Four eyes of four subjects with keratoconus were examined by slit lamp biomicroscopy, Orbscan II slit-scanning elevation topography (Bausch & Lomb Surgical, Rochester, NY), and laser scanning in vivo confocal microscopy with the Heidelbe...

We propose a method of calculating the corneal asphericity (Q) and analyze the characteristics of the anterior corneal shape using the tangential radius. Fifty-eight right eyes of 58 subjects were evaluated using the Orbscan II corneal topographer. The Q-values of the flat principal semi-meridians calculated by the sagittal radius were compared to those by the tangential radius. Variation in th...

PURPOSE To report the use of intracorneal ring segment (ICRS) implantation in a case of severe corneal thinning and irregularity secondary to alkali burn. CASE REPORT A 33-year-old man who had a history of ocular alkali burn in the right eye was admitted. His best corrected visual acuity was 0.16 with manifest refraction of +5.00 (-7.00 × 180°). Orbscan II(®) revealed steepening of >53 D supe...

Aim: To study the posterior corneal topographic changes in eyes with partial flaps during laser assisted in situ keratomileusis (LASIK). Methods: Case records of 16 patients, who had partial flap in one eye during LASIK (group 1) and uncomplicated surgery in the other eye (group 2), were studied. Following occurrence of partial flap intraoperatively, laser ablation was abandoned in all the eyes...

PURPOSE To test a pseudophakic eye model that allows for intraocular lens power (IOL) calculation, both in normal eyes and in extreme conditions, such as post-LASIK. METHODS PARTICIPANTS The model's efficacy was tested in 54 participants (104 eyes) who underwent LASIK and were assessed before and after surgery, thus allowing to test the same method in the same eye after only changing corne...

The porcine eye is often used as an ex vivo animal model in ophthalmological research. It is well suited for investigations concerning refractive surgery; however, corneal topography data are scarce. This study investigated the corneal topography and pachymetry of the porcine eye to provide further reproducible data. We evaluated freshly enucleated porcine eyes (n = 16) by performing computeriz...

PURPOSE To report the anatomical and visual outcomes of double layered amniotic membrane transplantation (AMT) in eyes with advanced Pseudomonas keratitis leading to Descemetocele formation. METHODS This prospective interventional case series included 6 eyes of 6 female patients with pseudomonas keratitis caused by contact lens-induced infection who underwent double layered AMT. Surgery was p...