Search results for "Astigmatism"
showing 10 items of 91 documents
Genome-wide association study for refractive astigmatism reveals genetic co-determination with spherical equivalent refractive error: the CREAM conso…
2015
To identify genetic variants associated with refractive astigmatism in the general population, metaanalyses of genome-wide association studies were performed for: White Europeans aged at least 25 years (20 cohorts, N = 31,968); Asian subjects aged at least 25 years (7 cohorts, N = 9,295); White Europeans aged <25 years (4 cohorts, N = 5,640); and all independent individuals from the above three samples combined with a sample of Chinese subjects aged <25 years (N = 45,931). Participants were classified as cases with refractive astigmatism if the average cylinder power in their two eyes was at least 1.00 diopter and as controls otherwise. Genome-wide association analysis was carried out for e…
Evaluation of a new nomogram for Ferrara ring segment implantation in keratoconus
2021
AIM: To evaluate the short-term clinical outcomes of Ferrara rings in keratoconus using an optimized nomogram developed after several years of research and retrospective analysis of clinical data. METHODS: This prospective longitudinal non-comparative clinical trial evaluated 88 eyes of 88 patients (age 18-62y) with keratoconus diagnosis from two Spanish centers. Ferrara ring segment (AJL Ophthalmic) implantation was performed in all cases, using the mechanical procedure in 25 eyes (28.4%) and a femtosecond laser-assisted procedure in 63 eyes (71.6%). The ring segments implanted in each case were selected using a new optimized nomogram that considered variables such as anterior corneal asph…
Pràctica 4. Astigmatisme
2021
El document forma part dels materials docents programats mitjançant l'ajut del Servei de Política Lingüística de la Universitat de València Guió de la quarta pràctica de l'assignatura d'Òptica Fisiològica del Grau d'Òptica i Optometria de la Universitat de València Script of the fourth practice of Physiological Optics subject of the Optics and Optometry Degree of the University of Valencia
Redzes refraktīvo defektu izplatība skolas vecuma bērniem
2021
Darbs ir uzrakstīts latviešu valodā uz 28 lapaspusēm, satur 7 attēlus, 10 tabulas, un 28 atsauces uz literatūras avotiem. Darba mērķis bija novērtēt nekoriģēto redzes refraktīvo defektu izplatību skolas vecuma bērniem dažādās vecuma grupās. Pētījumā tika izmantoti 11033 skolēnu dati no LU skrīninga projekta “Skolas vecuma bērnu redzes un redzes uztveres traucējumu pētīšana un diagnostikas metodiku izstrāde”. Tika analizēta refraktīvo defektu izplatības atkarībā no vecuma un smaguma pakāpes. Nekoriģētie redzes refraktīvie defekti tika konstatēti 8,5 % skolēniem, no tiem 25,8 % skolēniem novēroja miopiju, 11,1 % – hipermetropju, un 22,4 % vienkāršo vai saliktu astigmatismu. Refraktīvo defektu…
Femtosecond‑LASIK outcomes using the VisuMax®‑MEL® 80 platform for hyperopia and hyperopic astigmatism refractive surgery
2021
The present study evaluated the efficacy, the safety and the predictability of the Femtosecond laser-assisted in situ keratomileusis (Femto-LASIK) procedure for hyperopia and hyperopic astigmatism. We retrospectively analyzed the postoperative 12-month evolution of 593 eyes with hyperopia and hyperopic astigmatism that underwent Femto-LASIK treatment. The procedure was predictable and effective. No eye lost 2 lines of corrected distance visual acuity (CDVA), demonstrating a safety profile of the procedure. Nine percent of the eyes gained at least one line of CDVA. The accuracy of the spherical equivalent after 12 months was 74% within ±1.0 diopter (D) of emmetropia. The refractive outcomes …
Heredity of interocular similarities in components of refraction: a population-based twin study among 66- to 79-year-old female twins.
2019
Purpose: To examine genetic influences on interocular similarities in ocular refraction and components of refraction among elderly female twins. Methods: Refraction was assessed in 94 monozygotic (MZ) and 74 dizygotic (DZ) female twins aged 66–78 years. Absolute values of interocular differences (Aniso variables) in spherical refraction (SR), refractive astigmatism (AST), spherical equivalent (SE), corneal refractive power (CR), corneal astigmatism (CAST), anterior chamber depth (ACD) and axial length (AL) were calculated. The differences between sisters in each of the Aniso variables were calculated and graded into two categories, best differentiating the groups, here isometropic and aniso…
Heritability of corneal refraction and corneal astigmatism: a population-based twin study among 66- to 79-year-old female twins.
2012
. Purpose: To examine the heritability of corneal refraction power (CR) and corneal astigmatism (AST) in older women. Methods: Corneal refraction and AST were measured by IOL master in 52 monozygotic (MZ) and 47 dizygotic (DZ) female twin pairs aged 66–79 years. The relative contribution of genetic and environmental factors to individual differences in CR was estimated by applying an independent pathway model to the twin data and AST by intraclass correlations (ICC). Results: For the right eye, mean CR was 44.58 dioptres (D) (standard deviation (SD) ±1.28) When comparing CR of the right and left eye between MZ and DZ, no significant difference was found. Mean AST was 0.77 D (SD ±0.44) wi…
Implantation of a custom intraocular lens with a 30-diopter torus for the correction of high astigmatism after penetrating keratoplasty.
2003
Abstract We present a 62-year-old woman who had implantation of an intraocular lens (IOL) with a torus of 30.0 diopters (D) in an eye after penetrating keratoplasty. The patient presented with cataract and a best corrected visual acuity of 20/400. Penetrating keratoplasty was performed in 1975 because of decompensated keratoconus. With a clear but inferiorly decentered corneal graft, visual acuity was limited because of keratoplasty-related high corneal astigmatism of 22.5@156 that could not be successfully treated with spectacles or contact lenses. A custom toric IOL with –30.0 D of cylindrical power was implanted in the capsular bag via a sclerocorneal tunnel incision. Additionally, a sph…
Toric phakic intraocular lens
2003
Abstract Objective To evaluate safety, efficacy, predictability, stability, complications, and patient satisfaction after implantation of Artisan toric phakic intraocular lenses (TPIOLs) for the correction of myopia or hyperopia with astigmatism. Design Prospective, nonrandomized, comparative (self-controlled) multicenter trial. Participants Seventy eyes of 53 patients (mean, 35 years; range, 22–59 years) with preoperative spherical equivalent between +6.50 and −21.25 diopters (D) and cylinder between 1.50 and 7.25 D. Methods Seventy eyes underwent implantation of a TPIOL with an optical zone of 5.0 mm (Artisan, Ophtec, Groningen, The Netherlands). The dioptric power of the intraocular lens…
Effects of Superficial Keratectomy in Peripheral Hypertrophic Subepithelial Corneal Opacification on Front and Back Corneal Astigmatism
2020
To evaluate changes of anterior and posterior corneal astigmatism after superficial keratectomy in peripheral hypertrophic subepithelial corneal opacification (PHSCO). Patients with PHSCO, who had ...