PURPOSE To report the time course of changes in corneal wavefront aberrations in a patient with pellucid marginal degeneration. CASE A 59-year-old man with pellucid marginal degeneration was followed-up annually with slit-lamp microscopy and videokeratography for 11 years. The anterior corneal height data of the videokeratography were expanded into the set of orthogonal Zernike polynomials to...

PURPOSE To simulate the effects of decentration on lower- and higher-order aberrations (LOAs and HOAs) and optical quality, by using measured wavefront error (WFE) data from a cat photorefractive keratectomy (PRK) model. METHODS WFE differences were obtained from five cats' eyes 19 +/-7 weeks after spherical myopic PRK for -6 D (three eyes) and -10 D (two eyes). Ablation-centered WFEs were co...

OBJECTIVE To report on 4-year follow-up of corneal higher-order aberrations and daily visual functions of myopic patients after laser in situ keratomileusis (LASIK). METHODS One hundred thirty four eyes of 67 patients who underwent LASIK guided by aspherical ablation were included in this study. The vision, corneal spherical aberration (SphA) and Coma were recorded before LASIK and at 6 month...

Purpose To compare corneal aberrations in former preterm infants to that of full-term infants. Methods A prospective cross-sectional study was carried out measuring the corneal shape with Scheimpflug imaging in former preterm infants of gestational age (GA) ≤32 weeks and full-term infants with GA ≥37 weeks now being aged between 4 to 10 years. The main outcome measures were corneal aberration...

Suggestions that peripheral imagery may affect the development of refractive error have led to interest in the variation in refraction and aberration across the visual field. It is shown that, if the optical system of the eye is rotationally symmetric about an optical axis which does not coincide with the visual axis, measurements of refraction and aberration made along the horizontal and verti...

PURPOSE This study reports the characteristics of corneal higher order aberrations (HOAs) in eyes with normal topographic pattern using the Pentacam scheimpflug system. METHODS In this prospective, observational, comparative study, 165 eyes of 97 patients separated into five groups based on corneal topographic patterns were enrolled. All eyes received a comprehensive ophthalmologic examinatio...

PURPOSE To evaluate the efficacy of AcrySof SN60WF aspheric intraocular lens (IOL) in decreasing spherical aberration and total higher order aberrations (HOAs) after cataract surgery compared to the spherical SN60AT lens. METHODS Wavefront analysis was conducted on 28 eyes of 28 patients that underwent un-complicated phacoemulsification with implantation of either SN60WF (15 eyes) or SN60AT l...

BACKGROUND To compare the corneal high-order aberrations (HOAs), asphericity and regularity after Q-value guided laser in situ keratomileusis (LASIK) and laser epithelial keratomileusis (LASEK) in high myopic astigmatism. METHODS In this retrospectively comparative study, we measured the corneal HOAs, asphericity indices (Q values) and corneal regularity indices preoperatively and 36 months p...

We made on-axis aberrations and horizontal peripheral refraction measurements of emmetropic subjects (spherical equivalent -0.88D to +0.75D) aged between 19 and 70 years. We found smaller changes in on-axis aberrations with age than has previously been reported, possibly because of the small refractive error range of our subject group. Higher order root-mean-squared aberrations increased by 26%...

OBJECTIVE To investigate the fluctuations in intraocular pressure during the day and to see if these are associated with changes in corneal shape and in the patterns of ocular aberrations. METHODS Intraocular pressure, corneal curvature, refractive error, spherical equivalent and aberrations (defocus (sphere); cylinder (astigmatism); coma, trefoil and third order spherical aberration) were me...