We formed a database gathering the wavefront aberrations of 50 healthy eyes measured with an original custom-built Shack-Hartmann aberrometer at a temporal frequency of 236 Hz, with 22 lenslets across a 7-mm diameter pupil, for a duration of 20 s. With this database, we draw statistics on the spatial and temporal behavior of the dynamic aberrations of the eye. Dynamic aberrations were studied o...

The aim of this study was to determine whether dynamic accommodation responds to isolated blur cues without feedback, and without changes in the distance of the object. Nine healthy subjects aged 21-40years were recruited. Four different aberration patterns were used as stimuli to induce blur with (1) the eye's natural, uncorrected, optical aberrations, (2) all aberrations corrected, (3) spheri...

BACKGROUND Corneal collagen cross-linking (CXL) is the only treatment currently available to arrest the progression of keratoconus. The procedure consists of photopolymerization of stromal collagen fibers induced by combined action of a photosensitizing substance (riboflavin or vitamin B2) and ultraviolet-A light. PURPOSE To determine changes in the ocular higher-order aberrations (HOAs) afte...

The effect of brief periods of monocular oblique viewing on axial refractive error in myopes and emmetropes was studied in 20 normal subjects. Refractive error and higher order aberrations were measured either with the subject's head positioned such that the subject looked straight into an aberrometer with the right eye or the subject's head rotated to the right or left by approximately 30 degr...

PURPOSE To compare forward shift of posterior corneal surface and higher-order aberration (HOA) changes after LASIK, LASEK, and wavefront-guided LASEK surgery in moderate myopia METHODS One hundred eighty four eyes undergoing LASIK, LASEK and wavefront-guided LASEK with VISX STAR S4 were included in this study. The posterior corneal elevation was measured with Orbscan before, 2 and 4 months a...

PURPOSE To determine changes in higher-order aberrations (HOAs) after corneal collagen crosslinking (CXL). SETTING Cornea and refractive surgery practice. DESIGN Prospective randomized controlled clinical trial. METHODS Corneal and ocular HOAs were measured and analyzed using the Pentacam device and Ladarwave aberrometer, respectively, at baseline and 12 months after CXL. RESULTS Ninety...

Purpose In this study, we investigated whether an individual's visual fatigue can be evaluated objectively and quantitatively from their ability to maintain binocular fusion. Methods Binocular fusion maintenance (BFM) was measured using a custom-made binocular open-view Shack-Hartmann wavefront aberrometer equipped with liquid crystal shutters, wherein eye movements and wavefront aberrations ...

Changes in pupil size and shape are relevant for peripheral imagery by affecting aberrations and how much light enters and/or exits the eye. The purpose of this study is to model the pattern of pupil shape across the complete horizontal visual field and to show how the pattern is influenced by refractive error. Right eyes of 30 participants were dilated with 1% cyclopentolate, and images were c...

The problem of measuring the objective refractive error with an aberrometer has shown to be more elusive than expected. Here, the formalism of differential geometry is applied to develop a theoretical framework of refractive error sensing. At each point of the pupil, the local refractive error is given by the wavefront curvature, which is a 2 × 2 symmetric matrix, whose elements are directly re...

AIM To compare visual performance of wavefront-guided laser in situ keratomileusis (LASIK) with iris-registration (Wg-LASIK group) and conventional LASIK (LASIK group) one year after surgery and analyze the correlation between wavefront aberrations and visual performance. METHODS Eight hundred and fifty-two myopic eyes of 430 patients were enrolled in this prospective study and divided into t...