Results 241 to 250 of about 23,253 (280)
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Investigation of posterior corneal curvature in CL-induced corneal swelling
Contact Lens and Anterior Eye, 2009To evaluate Orbscan II measurements without contact lens (CL) removal to monitor in vivo posterior corneal curvature in CL (hypoxia)-induced corneal swelling during extended wear (EW).Orbscan II corneal topographer was used to measure posterior corneal curvature 1 week before CL wearing and during 1 week of EW.
Raul, Martin +2 more
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Longitudinal Changes in Corneal Curvature in Keratoconus
Cornea, 2006This 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 +5 more
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Changes in corneal curvature following ocular convergence
Vision Research, 1965Abstract A method is described for the measurement of the radii of corneal curvature in the vertical and horizontal meridians. It was applied to the study of the change in curvature during the convergence of the ocular axes from an approximately primary position to a binocular fixation spot situated at some 5 metre-angles: (a) the eye under test ...
B, Löpping, R A, Weale
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Corneal Curvature Stability With Increased Intraocular Pressure
Eye & Contact Lens: Science & Clinical Practice, 2007To examine the corneal shape and ocular refraction under conditions of increased intraocular pressure (IOP) and to consider the possible influences of direct digital forces, corneal thickness, limbal and scleral rigidity, and the duration and frequency of IOP loading on the results.Forces applied digitally to the temporal sclera were used to obtain 15 ...
Charles W, McMonnies, Gavin C, Boneham
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POSITION AND CURVATURE OF THE CORNEAL APEX
Optometry and Vision Science, 1969Methods to measure the position of the corneal apex are reviewed and evaluated. The recommended method is with a small-mire keratometer that has a target mounted independently of the drum. The corneal apexes for eight subjects were found to be decentered from their lines of sight but a directional trend was not apparent.
R B, Mandell, R, St Helen
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Corneal curvature and trachoma.
Annals of ophthalmology, 1984In 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
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Posterior corneal curvature and its influence on corneal dioptric power
Acta Ophthalmologica, 1994Abstract. An algorithm for estimation of the posterior corneal curvature is presented and applied on data from normal and keratoconic eyes. Radius of central posterior corneal curvature are demonstrated to be (mean ± sd) 6.71 ± 0.23 mm and 5.58 ± 0.78 mm in normals and keratoconic eyes, respectively.
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Polynomial Approximations of Corneal Surfaces And Corneal Curvature Topography
Ophthalmic and Visual Optics, 1992Machines for the measurement of corneal topography typically produce a colored topographic map of the mean curvature of the cornea. (1). From the examination of a number of such maps of normal corneas it has been found that the normal cornea is most curved at its apex and flatter in the periphery. By contrast, a cornea flattened by corneal surgery will
H. C. Howland, A. Glasser, R. Applegate
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[Corneal curvature of myopia].
Nippon Ganka Gakkai zasshi, 1993We 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 +4 more
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Central corneal thickness and corneal curvature in patients with rheumatoid arthritis
International Ophthalmology, 2016The 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 +4 more
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