Search results for "Contrast sensitivity"
showing 5 items of 115 documents
Bilateral Ultrathin Descemet’s Stripping Automated Endothelial Keratoplasty vs. Bilateral Penetrating Keratoplasty in Fuchs’ Dystrophy: Corneal Highe…
2021
Background and Objectives: The objective of this paper is to compare the visual outcomes and quality of life (QoL) after bilateral ultrathin Descemet’s stripping automated endothelial keratoplasty (UT-DSAEK) with bilateral penetrating keratoplasty (PK) for Fuchs’ endothelial dystrophy (FED). Materials and Methods: Retrospective comparative cohort study, including 11 patients with FED who underwent bilateral PK and 13 patients with FED who underwent bilateral UT-DSAEK. All patients were already pseudophakic or had undergone a combined cataract procedure. The main outcomes were corrected distance visual acuity (CDVA) corneal higher-order aberrations (HOAs), contrast sensitivity (CS) and quali…
Visual acuity and contrast sensitivity screening with a new iPad application
2016
We present a new iPad application (app) for a fast assessment of Visual Acuity (VA) and Contrast Sensitivity (CS) whose reliability and agreement was evaluated versus a commercial screening device (Optec 6500). The measurement of VA was programmed in the app in accordance with the Amblyopia Treatment Study protocol. The CS was measured with sinusoidal gratings of four different spatial frequencies: 3, 6, 12 and 18 cpd at the same contrast values of the Functional Acuity Contrast Test (FACT) included in the Optec 6500. Forty-five healthy subjects with monocular corrected visual acuities better than 0.2 logMAR participated in the agreement study. Bland-Altman analyses were performed to assess…
Impact of the pupil size – central optical zone diameter relationship on visual performance in aspheric multifocal contact lenses
2020
Abstract Purpose To determine the impact of different central optical zone diameters (COZDs), obtained from pupil size, on the visual performance of presbyopic subjects fitted with centre-distance simultaneous-image multifocal contact lenses (SIMCLs). Methods Thirty-two presbyopic volunteers, between 45–58 years of age, participated in this prospective, controlled, double-blind study. Subjects were fitted with 5 centre-distance SIMCLs of variable COZD, determined from the measurement of pupil size under photopic light conditions and corresponding to 60, 70, 80, 90 and 100 % of pupil diameter. Subjects visual performance was evaluated through the measurement of distance, intermediate and nea…
Effect of Varying Levels of Glare on Contrast Sensitivity Measurements of Young Healthy Individuals Under Photopic and Mesopic Vision
2018
Contrast sensitivity (CS), the ability to detect small spatial changes of luminance, is a fundamental aspect of vision. However, while visual acuity is commonly measured in eye clinics, CS is often not assessed. At issue is that tests of CS are not highly standardized in the field and that, in many cases, optotypes used are not sensitive enough to measure graduations of performance and visual abilities within the normal range. Here, in order to develop more sensitive measures of CS, we examined how CS is affected by different combinations of glare and ambient lighting in young healthy participants. We found that low levels of glare have a relatively small impact on vision under both photopi…
Reading ability with 3 multifocal intraocular lens models.
2006
Purpose To prospectively evaluate reading performance with of 3 types of multifocal intraocular lenses (IOLs) under different lighting conditions based on reading acuity and reading speed tests. Setting Augenklinik, Bad Hersfeld, Germany. Methods This randomized study comprised 60 cataract patients (120 eyes) randomly assigned to receive an SA40N IOL (AMO) (Group 1, 20 patients), Tecnis ZM001 IOL (AMO) (Group 2, 20 patients), or AcrySof ReSTOR SA60D3 IOL (Alcon) (Group 3, 20 patients). Pupil size and reading ability at near (visual acuity, reading speed) without correction, with best distance correction, and with best near correction were assessed 6 weeks postoperatively under low-light con…