Search results for "Corneal Wavefront Aberration"
showing 10 items of 35 documents
Visual performance of the Akreos Adapt AO intraocular lens in patients with different corneal profiles measured with an adaptive optics visual simula…
2012
AIMS: To evaluate the visual performance of an aberration-free intraocular lens (IOL) in patients with different corneal profiles using adaptive optics visual simulation. METHODS: A crx1 adaptive optics visual simulator was used to simulate the aberration pattern of an aberration-free IOL combined with five corneal profiles: virgin corneas and corneas with low and high myopic ablations and low and high hyperopic ablations. Ten eyes of 10 subjects were evaluated, and monocular distance visual acuity (VA) at 100%, 50% and 10% of contrast was measured. RESULTS: At 100% of contrast, no differences were found in VA values among virgin corneas, low and high myopic ablations and low hyperopic abla…
Effect of Simulated IOL Tilt and Decentration on Spherical Aberration After Hyperopic LASIK for Different Intraocular Lenses
2011
PURPOSE: To evaluate visual quality differences among intraocular lenses (IOLs) in patients with previous hyperopic laser ablations and to assess the impact of decentration and tilt of IOLs on visual quality. METHODS: An adaptive optics visual simulator was used to simulate the wavefront aberration pattern of one aberration-correcting IOL (AcrySof IQ SN60WF, Alcon Laboratories Inc) and two spherical IOLs with different amounts of positive spherical aberration (Akreos Adapt [Bausch & Lomb] and Triplato [AJL Ophthalmic]) in five situations—centered, 0.2 mm and 0.4 mm of decentration, and 2° and 4° of tilt—in two groups: simulated low hyperopic laser corneal ablation (low hyperopia group)…
Visual simulation through an aspheric aberration-correcting intraocular lens in subjects with different corneal profiles using adaptive optics.
2013
The aim of this study was to analyse the visual quality of the AcrySof IQ SN60WF® intraocular lens (IOL) when combined with different corneal profiles. Ten eyes of 10 participants with no prior history of refractive or cataract surgery were evaluated. An adaptive optics visual simulator was used to simulate the wavefront aberration pattern of an aspheric aberration-correcting IOL (AcrySof IQ SN60WF®). Normal corneas (group A), low and high myopic corneal ablations (groups B and C, respectively) and low and high hyperopic corneal ablations (groups D and E, respectively) were also simulated. Monocular distance visual acuities at 100, 50 and 10 per cent of contrast were measured. At 100, 50 an…
Lentes de contato corneoesclerais adaptadas em córneas irregulares após cirurgia LASIK
2018
ABSTRACT Purpose: We aimed to describe the outcomes of corneoscleral contact lens fitting with multi-aspherical geometry designs in patients with irregular corneas after laser-assisted in situ keratomileusis (LASIK). Methods: This was a retrospective series of 18 patients (age, 26-38 years) selected from an eye clinic database. Participants were required to have unsatisfactory visual acuity with their current contact lenses or spectacles after LASIK for myopia correction. All patients were fitted with corneoscleral contact lenses designed to correct corneal surface irregularities. A diagnostic trial set was used for fitting, and assessments were performed according to a standardized methodo…
Visual simulation through different intraocular lenses using adaptive optics: Effect of tilt and decentration
2011
Purpose To analyze visual quality differences between intraocular lenses (IOLs) and assess the impact of IOL decentration and tilt on visual quality. Setting University of Valencia, Valencia, Spain. Design Cohort study. Methods The crx1 adaptive optics visual simulator was used to simulate the wavefront aberration pattern of 2 commercially available aspheric aberration-correcting IOLs (Acrysof IQ SN60WF and Tecnis ZA9003) and 2 spherical IOLs (Akreos Adapt and Triplato) in 5 situations: centered, decentered 0.2 mm and 0.4 mm, and tilted 2 degrees and 4 degrees. Monocular distance visual acuity at 100%, 50%, and 10% contrast and the depth of focus were measured. Results Ten eyes of 10 patien…
Simulated prototype of posterior chamber phakic intraocular lens for presbyopia correction.
2014
Purpose To evaluate the visual impact of adding different spherical aberration values to an Implantable Collamer Lens phakic intraocular lens (pIOL) to increase the depth of focus using an adaptive optics visual simulator. Setting University of Valencia, Valencia, Spain. Design Experimental study. Methods Wavefront aberrations in −3.00 D and −6.00 diopter (D) pIOLs were measured in vitro. Afterward, different simulated pIOL experimental prototypes were created along with variances in the spherical aberration. An adaptive optics visual simulator was used to simulate vision after the implantation of the different pIOL prototypes from their wavefront aberrations. The corrected distance visual …
Depth of focus through different intraocular lenses in patients with different corneal profiles using adaptive optics visual simulation
2011
PURPOSE: To evaluate the depth of focus with monofocal intraocular lenses (IOLs) in patients with different corneal profiles using adaptive optics (AO) visual simulation. METHODS: An AO visual simulator (crx1, Imagine Eyes) was used to simulate the aberration pattern of three monofocal IOLs (Acrysof IQ SN60WF [Alcon Laboratories Inc]; Akreos Adapt AO [Bausch & Lomb]; and Triplato [AJL Ophthalmic]) of different optic designs. Five groups were considered: patients without any corneal refractive surgery (normal cornea group) and with prior low and high myopic and hyperopic ablations (low myopic ablation, high myopic ablation, low hyperopic ablation, and high hyperopic ablation groups). De…
Intrasubject repeatability of corneal power, thickness, and wavefront aberrations with a new version of a dual rotating Scheimpflug–Placido system
2014
Purpose To determine the intrasubject repeatability of a recently introduced dual-camera rotating Scheimpflug–Placido imaging system (Galilei G4) in determining corneal thickness, power, and wavefront aberrations in young healthy subjects. Setting University of Valencia, Valencia, Spain. Design Prospective evaluation of diagnostic technology. Methods The study comprised right eyes of 25 subjects aged 20 to 40 years with a spherical equivalent ranging from −4.25 to +1.00 diopters. The central corneal thickness, thinnest point value and location, anterior and posterior surface curvatures, total corneal power, and corneal wavefront aberrations were measured for distance vision using the dual S…
Precision of a commercial hartmann-shack aberrometer: limits of total wavefront laser vision correction.
2012
Purpose To assess the intrasession and intersession precision of higher-order aberrations (HOAs) measured using a commercial Hartmann-Shack wavefront sensor (Zywave; Bausch & Lomb) in refractive surgery candidates. Design Prospective, experimental study of a device. Methods To analyze intrasession repeatability, 1 experienced examiner measured 30 healthy eyes 5 times successively. To study intersession reproducibility, the same clinician obtained measurements from another 30 eyes in 2 consecutive sessions at the same time of day 1 week apart. Results For intrasession repeatability, excellent intraclass correlation coefficients (ICCs) were obtained for total ocular aberrations, total HOAs, a…
The effect of aberrations on objectively assessed image quality and depth of focus
2017
The effects of aberrations on image quality and the objectively assessed depth of focus (DoF) were studied. Aberrometry data from 80 young subjects with a range of refractive errors was used for computing the visual Strehl ratio based on the optical transfer function (VSOTF), and then, through-focus simulations were performed in order to calculate the objective DoF (using two different relative thresholds of 50% and 80%; and two different pupil diameters) and the image quality (the peak VSOTF). Both lower order astigmatism and higher order aberration (HOA) terms up to the fifth radial order were considered. The results revealed that, of the HOAs, the comatic terms (third and fifth order) ex…