Results 241 to 250 of about 276,917 (287)

Effect of the menstrual cycle on corneal curvature

Ophthalmic and Physiological Optics, 1996
Summary The purpose of this research was to determine if a clinically significant variation in corneal curvature occurs with the menstrual cycle. The EyeSys™ Corneal Analysis System™ (CAS) was used to measure corneal curvature of a test group of three normally menstruating female subjects over three cycles and compared with a control ...
Oliver, Katherine M., Walsh, Glyn, Tomlinson, Alan, McFadyen, Angus, Hemenger, Richard P.   +4 more
openaire   +3 more sources

The effect of incisions for cataract on corneal curvature

Ophthalmology, 2003
To determine the magnitude and duration of change on the horizontal and vertical meridians of the cornea after five different incisions for cataract.Retrospective comparative interventional study of five commonly used incisions for cataract surgery: extracapsular cataract extraction (ECCE), 6-mm superior scleral tunnel (6Sup), 3-mm superior scleral ...
John C, Merriam, Lei, Zheng, Joanna E, Merriam, Marco, Zaider, Bo, Lindström   +4 more
openaire   +2 more sources

Surgery in an Attempt to Change Corneal Curvature

Ophthalmic Surgery, Lasers and Imaging Retina, 1981
SUMMARY An historical review up to 1952 of surgical methods intended to change the refractive power of the eye is given. Experimental work at Yale utilizing 49 rabbits and dogs includes repeated prior studies done by others. This work incorporated: 1.
W, Szuniewicz, R M, Fasanella
openaire   +2 more sources

DIURNAL VARIATION IN CENTRAL CORNEAL CURVATURE

Optometry and Vision Science, 1970
ABSTRACT Various changes in central corneal curvature have been reported. One possible reason for these apparent changes is diurnal variation. After testing the ability of the average clinician accurately and repeatedly to make keratometric readings, we sought to determine if diurnal variation
D R, Reynolds, H L, Poynter
openaire   +2 more sources

Longitudinal Changes in Corneal Curvature in Keratoconus

Cornea, 2006
This study was designed to identify factors that predict longitudinal increases in corneal curvature as measured by the First Definite Apical Clearance Lens (FDACL) and flatter keratometric reading (Flat K) in keratoconus.The Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study is a long-te rm evaluation of the natural history of ...
Timothy T, McMahon, Timothy B, Edrington, Loretta, Szczotka-Flynn, Harald E, Olafsson, Larry J, Davis, Kenneth B, Schechtman   +5 more
openaire   +2 more sources

ODE/PDE analysis of corneal curvature

Computers in Biology and Medicine, 2014
The starting point for this paper is a nonlinear, two-point boundary value ordinary differential equation (BVODE) that defines corneal curvature according to a static force balance. A numerical solution to the BVODE is computed by first converting the BVODE to a parabolic partial differential equation (PDE) by adding an initial value (t, pseudo-time ...
Lukasz Plociniczak, Graham W. Griffiths, William E. Schiesser   +2 more
openaire   +2 more sources

Central corneal thickness and corneal curvature in patients with rheumatoid arthritis

International Ophthalmology, 2016
The aims of this study were to determine the central corneal thickness (CCT) and corneal curvature (CC) in patients with rheumatoid arthritis (RA), and to evaluate the correlations between the CCT, CC, RA activity, and RA duration. Fifty-four RA patients (104 eyes; 35 with dry eye, 69 without dry eye) and 21 age- and gender-matched control patients (42
Özcura, Fatih, Aktaş S., Özkan Y., Tetikoğlu M., Sağdik H.M.   +4 more
openaire   +3 more sources

Corneal curvature and thickness – Scheimpflug

Acta Ophthalmologica, 2022
AbstractAlthough the Scheimpflug principle was first described over a century ago, the clinical use of Scheimpflug camera in anterior segment imaging started only a decade ago. Scheimpflug imaging has since advanced significantly and modern instruments provide comprehensive imaging and topographic data of the anterior segment using a noncontact method.
openaire   +1 more source

[Corneal curvature of myopia].

Nippon Ganka Gakkai zasshi, 1993
We classified myopia by total refractive error, measured the corneal curvature, and analyzed the relationship between the diopter value and corneal curvature in growing teen-agers and in adults in their twenties, whose myopic progress is presumed to have stopped. We adopted as the harmonic average the central 3.0 mm of the cornea.
H, Yamaguchi, K, Kobari, H, Shioya, M, Kajita, K, Kato   +4 more
openaire   +1 more source

Corneal curvature and trachoma.

Annals of ophthalmology, 1984
In a study of 141 cases in different stages of trachoma, a definite change was observed in the curvature of upper part of cornea, which had become ectatic. The difference in curvature depended on the stage and severity of the trachoma. Most of the patients had fourth stage trachoma.
R P, Bhatia, P, Awasthy
openaire   +1 more source