PURPOSE Ocular refraction is measured in spherical equivalent as the power of the external lens required to focus images on the retina. Myopia (nearsightedness) and hyperopia (farsightedness) are the most common refractive errors, and the leading causes of visual impairment and blindness in the world. The goal of this study is to identify rare and low-frequency variants that influence spherical...

PURPOSE To evaluate refractive state in children with unilateral congenital nasolacrimal duct obstruction (NLDO). METHODS This descriptive cross-sectional study includes consecutive children with unilateral congenital NLDO. Examination under anesthesia was performed to perform cycloplegic refraction and was followed by appropriate intervention in each patient. Refractive errors of the involve...

purpose: to determine the long-term visual outcomes and complications of penetrating keratoplasty (pk) performed for keratoconus. methods: hospital records of patients with keratoconus who underwent pk at the ophthalmology center of shaheed sadoughi, yazd, iran, during 1992-2003 were reviewed. we studied records of 84 pk procedures in 72 keratoconus patients. data including best corrected visua...

PURPOSE To evaluate the efficacy of unilateral photorefractive keratectomy to correct anisometropia induced by retinal detachment surgery. METHODS Photorefractive keratectomy was performed in 10 eyes of 10 patients with anisometropia induced by previous retinal detachment surgery. The Aesculap Meditec MEL 60 excimer laser was used. RESULTS Preoperative mean spherical equivalent refraction w...

PURPOSE To compare the agreement between subjective refraction and autorefraction using two commercially available autorefractors. METHODS Prospective data were collected for 190 subjects using either the Nidek ARK-700A (Fremont, CA) or the Topcon KR-8000 (Paramus, NJ) and subjective refraction (masked to autorefraction). Refractions were compared in terms of spherical equivalent using Bland-...

PURPOSE To report the visual and refractive outcomes of small incision lenticule extraction for low myopia using the VisuMax femtosecond laser (Carl Zeiss Meditec, Jena, Germany). METHODS A retrospective analysis of 120 consecutive small incision lenticule extraction procedures was performed for low myopia. Inclusion criteria were preoperative spherical equivalent refraction up to -3.50 diopt...