Objective: To compare the ocular wavefront aberrations of normal and keratoconic eyes and to describe the characteristics of the higher-order aberrations in eyes with keratoconus.
Design: Prospective case control and observational study.
Participants: Thirty-five keratoconic eyes and thirty-eight normal controls.
Methods: Higher-order aberrations in refraction were measured with a wavefront sensor, and those aberrations resulting from the cornea were evaluated by videokeratographic data.
Main Outcome Measures: Coma-like (S(3 + 5)), spherical-like (S(4 + 6)), and total (S(3 + 4 + 5 + 6)) higher-order aberrations in both refraction and the cornea.
Results: The mean +/- standard deviation of S(3 + 5) (1.88 +/- 1.16), S(4 + 6) (0.70 +/- 0.55), and S(3 + 4 + 5 + 6) (2.03 +/- 1.23) in refraction (6-mm diameter, root mean square, micro m) were significantly higher in the keratoconic eyes than in normal controls (0.26 +/- 0.10, 0.19 +/- 0.10, 0.34 +/- 0.11, respectively; Mann-Whitney U test, P = 0.001). Coma-like aberrations were 2.32 times larger than spherical-like aberrations in keratoconic eyes.
Conclusions: The increase of ocular higher-order aberrations in keratoconic eyes results from an increase of corneal higher-order aberrations. Coma-like aberrations were dominant compared with spherical-like aberrations in keratoconic eyes. Wavefront sensing will enable us not only to evaluate the quality of vision but also to differentiate keratoconic eyes from normal eyes by analyzing the characteristics of the higher-order aberrations.
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http://dx.doi.org/10.1016/s0161-6420(02)01279-4 | DOI Listing |
J Clin Med
January 2025
Department of Ophthalmology, St. Barbara Hospital, Trauma Centre, 41-200 Sosnowiec, Poland.
The aim of this retrospective study was to compare corneal parameters and compliance using a Pentacam HR-Scheimpflug (Pentacam HR) and a swept-source OCT Casia (Casia) in keratoconus (KC) patients post penetrating keratoplasty (PKP) and KC patients without PKP, as well as a control group. Pachymetry measurements were also analyzed using a spectral domain OCT Solix (OCT Solix), Pentacam HR, and Casia. The study included 71 patients (136 keratoconic eyes; group A), 86 eyes with KC post-PKP (group B), 50 eyes with KC without PKP (group C), and 52 control participants (104 eyes).
View Article and Find Full Text PDFCureus
November 2024
Ophthalmology, International University of Health and Welfare, Chiba, JPN.
Keratoconus is a condition that causes progressive thinning and anterior protrusion of the cornea. Because of its irregular astigmatism, mild to moderate keratoconus is corrected with hard contact lenses (HCLs), but blepharoptosis due to the long-term wearing of HCLs is often a problem. In this study, we investigated blepharoptosis in HCL wearers with keratoconus.
View Article and Find Full Text PDFAim: To evaluate the long-term impact of accelerated corneal cross-linking (A-CXL) on selected refractive and topographical parameters in eyes with progressive keratoconus.
Methods: 77 eyes with keratoconus in 54 patients treated with A-CXL (10 min "epi-off" protocol) were included in the analysis. Preoperative and postoperative (1, 3 and 5 years after A-CXL) values of the studied parameters were compared.
Ophthalmic Physiol Opt
December 2024
Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany.
Purpose: To compare the parameters and indices of a novel swept-source optical coherence tomography device (SS-OCT, ANTERION) with those of a rotating Scheimpflug camera (RSC)-based tomograph (Pentacam) in normal and keratoconic (KC) eyes.
Methods: This prospective, monocentric, cross-sectional study included individuals with unoperated normal and KC eyes, selecting one eye per subject. Ectasia-specific parameters analysed with the SS-OCT were difference in mean keratometry (K) in the inferior and superior meridians, maximum keratometry value (K), elevation of the posterior surface at the thinnest point, screening corneal objective risk of ectasia (SCORE) and thinnest point thickness.
Int Ophthalmol
November 2024
Anterior Segment Surgery Department, Asociación Para Evitar La Ceguera en México I.A.P., Vicente García Torres 46, Barrio San Lucas, CP 04030, Coyoacán, Mexico City, Mexico.
Purpose: To describe the accuracy of monofocal intraocular lens power calculation in patients with keratoconus using total keratometry (TK) and standard keratometry (K) with conventional and keratoconus-modified formulas.
Setting: Asociación Para Evitar la Ceguera en México, Mexico City, Mexico.
Design: Observational, retrospective, non-randomized, comparative study.
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