Search results for "Visual Acuity"
showing 10 items of 456 documents
Refractive changes in nuclear, cortical and posterior subcapsular cataracts. Effect of the type and grade
2015
Purpose: To determine the effect of main morphological types and grades of age-related cataracts on refractive error. Methods: We measured 276 subjects with optical compensation prior to the development of cataract. We evaluated 224 eyes with nuclear cataract, 125 with cortical cataract, and 103 with posterior subcapsular (PSC) cataract classified with LOCSIII. We measured visual acuity (VA) with their spectacles and best-corrected visual acuity (BCVA) with chart in decimal scale to obtain the optimal compensation with cataract. We evaluated the differences between compensations. Results: A significant myopic shift was observed in nuclear cataract from low to mild grade (p = 0.031), the sam…
Optical and visual performance of diffractive intraocular lens implantation after myopic laser in situ keratomileusis
2008
To evaluate the optical and visual quality in eyes with diffractive intraocular lenses (IOLs) after myopic laser in situ keratomileusis (LASIK).Fernández-Vega Ophthalmological Institute, Oviedo, Spain.The best corrected visual acuity (BCVA [distance]) at 12.5%, 25.0%, and 100% contrasts under photopic and mesopic conditions; best distance-corrected near acuity; corneal total higher-order aberrations (HOAs); and optical quality by modulation transfer function (MTF) were measured after myopic LASIK in eyes with a spherical AcrySof ReSTOR SN60D3 IOL or an aspheric Acri.LISA 366D IOL and phakic eyes (control).Under photopic conditions at 100% contrast, the BCVA was 0.1 logMAR or better in all g…
Visual quality after diffractive intraocular lens implantation in eyes with previous hyperopic laser in situ keratomileusis
2010
To evaluate distance, intermediate, and near visual quality in eyes with diffractive intraocular lens (IOL) implantation after previous hyperopic laser in situ keratomileusis (LASIK).Fernández-Vega Ophthalmological Institute, Oviedo, Spain.Cohort study.Corrected distance visual acuity (CDVA) at 12.5%, 25.0%, and 100% contrast levels under photopic and mesopic conditions; uncorrected (UNVA) and distance-corrected (DCNVA) near visual acuity, defocus curves, and corneal higher-order aberrations (HOAs) were measured in eyes that had AcrySof Restor SN60D3 spherical IOL implantation (study group) and in phakic eyes (control group) after hyperopic LASIK.Under photopic conditions at 100% contrast, …
Toric intraocular lens versus opposite clear corneal incisions to correct astigmatism in eyes having cataract surgery.
2009
To compare toric intraocular lens (IOL) implantation with paired opposite clear corneal incisions (OCCIs) for astigmatism correction in patients having cataract surgery.Ophthalmology Service, Donostia Hospital, San Sebastián, Spain.This randomized prospective clinical study comprised eyes with more than 1.00 diopter (D) of preexisting corneal astigmatism. One group had AcrySof toric IOL implantation and the other, paired 2.75 mm/3.20 mm OCCIs in the steep axis with spherical IOL implantation. Uncorrected (UCVA) and best corrected (BCVA) visual acuity, refraction, corneal and total higher-order aberrations (HOAs), photopic and mesopic contrast sensitivity, and toric IOL axis were measured 3 …
Implantation of a toric poly(methyl methacrylate) intraocular lens to correct high astigmatism
1999
Abstract A 57-year-old man experienced a decrease in visual function because of cataract formation. Corneal astigmatism was 13.4 diopters (D) because he had had a penetrating keratoplasty 27 years before. Cataract surgery was planned, and biometric data for toric intraocular lens (IOL) implantation were collected for the manufacture of a custom IOL. After phacoemulsification, a toric poly(methyl methacrylate) (PMMA) IOL of +19.0 D spherical and +12.0 D cylindrical power was implanted via a sclerocorneal tunnel incision. Three months postoperatively, corneal astigmatism was 14.3 D and best corrected visual acuity (BCVA), 20/25. Postoperative refraction (+1.5 −3.0 × 90) and BCVA remained stab…
Effect of head position on refraction in aphakic and phakic silicone-filled eyes.
1997
BACKGROUND The refraction of the eye is altered significantly after the instillation of silicone oil into the vitreous cavity because of the silicone oil's high refractive index. The degree of the refractive change shows diurnal variation and depends on the patient's head position. PATIENTS AND METHODS To analyze the degree and time course of refractive changes with respect to head position, the authors performed objective refraction in five aphakic and five phakic silicone oil-instilled eyes with attached maculae using an automatic hand-held refractometer. In each patient, 25 measurements were taken at short intervals using a hand-held autorefractometer with the patient in different positi…
Intermediate visual function with different multifocal intraocular lens models
2009
Purpose To compare visual acuity at different distances after bilateral implantation of 1 of 4 multifocal intraocular lenses (IOLs). Setting Fernandez-Vega Ophthalmological Institute, Oviedo, Spain. Methods This study evaluated consecutive patients who had bilateral implantation of a spherical multifocal IOL with a +4.00 diopter (D) addition (add) (AcrySof ReSTOR SN60D3) or an aspheric multifocal IOL with a +4.00 D add (AcrySof ReSTOR SN6AD3), +3.75 D add (Acri.LISA 366D), or +3.00 D add (AcrySof ReSTOR SN6AD1). Six months postoperatively, binocular measurement of corrected distance visual acuity (CDVA) at 4 m, corrected near visual acuity (CNVA) at 40 cm, and corrected intermediate visual …
Visual acuity comparison of 2 models of bifocal aspheric intraocular lenses.
2008
Purpose To compare visual acuity after bilateral implantation of 2 models of multifocal aspheric intraocular lenses (IOLs). Setting Fernandez-Vega Ophthalmological Institute, Oviedo, and University of Valencia, Valencia, Spain. Methods Prospective study of patients who had bilateral implantation of an AcrySof ReSTOR SN6AD3 IOL (Group 1) or an Acri.LISA 366D IOL (Group 2). Six months postoperatively, binocular uncorrected and best corrected distance visual acuity, uncorrected-distance and best distance-corrected near visual acuity, best corrected intermediate visual acuity, and the defocus curve were measured in both IOL groups. Results Group 1 comprised 36 eyes (18 patients) and Group 2, 40…
Visual Acuity and Contrast Sensitivity in Eyes Implanted with Aspheric and Spherical Intraocular Lenses
2009
Purpose To compare visual acuity and contrast sensitivity (CS) in eyes implanted with aspheric and spherical intraocular lenses (IOLs) after cataract surgery. Design Randomized, prospective study. Participants Five hundred twenty-four eyes from 262 cataract surgery patients implanted with 2 IOL models: the AcrySof IQ (262 eyes) and AcrySof SN60AT (262 eyes; Alcon Laboratories, Fort Worth, TX). Methods High-contrast photopic best-corrected distance visual acuity (BCVA) and CS under photopic (85 cd/m 2 ) and mesopic (6 cd/m 2 ) conditions were measured. Pupil diameter was analyzed for distance vision under both lighting conditions. Follow-up was carried out for 6 months in all patients. Main …
Refractive and Visual Results after Implantation of the AcrySof ReSTOR IOL in High and Low Hyperopic Eyes
2009
To assess the differences in refractive and visual results obtained in eyes with high and low hyperopia after implantation of a multifocal intraocular lens (IOL).A prospective study was performed on 172 hyperopic eyes implanted with the AcrySof Re-STOR Natural (SN60D3) IOL. Two groups were created, high and low hyperopes (86 eyes in both cases). We analyzed monocular visual acuity for distance and near, with and without distance correction. Photopic and mesopic contrast sensitivity (CS) were also assessed. All measurements were performed at 6 months after surgery.Monocular best distance-corrected visual acuity was 0.01+/-0.03 logMAR for low hyperopes and 0.04+/-0.10 logMAR for high hyperope…