keratoscope

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keratoscope

 [ker´ah-to-skōp″]
a device consisting of alternate black and white concentric circles and used for examining corneal curvature.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

ker·a·to·scope

(ker'ă-tō-skōp'),
An instrument marked with lines or circles by means of which the corneal reflex can be observed.
[kerato- + G. skopeō, to examine]
Farlex Partner Medical Dictionary © Farlex 2012

ker·a·to·scope

(ker'ă-tō-skōp)
An instrument marked with lines or circles by means of which the corneal reflex can be observed.
Synonym(s): Placido da Costa disc.
[kerato- + G. skopeō, to examine]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

keratoscope

An instrument from which bright concentric circles can be reflected by the CORNEA so as to reveal optical irregularities of the surface.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

keratoscope

Instrument for examining the front surface of the cornea. It consists of a pattern of alternately black and white concentric rings reflected by the cornea and seen through a convex lens mounted in an aperture at the centre of the pattern. Such an instrument gives a qualitative evaluation of large corneal astigmatism, and is useful in cases of irregular astigmatism as in keratoconus, for example (Fig. K3). Syn. Placido disc. See corneal topography; photokeratoscopy; videokeratoscope.
Fig. K3 Keratoscopeenlarge picture
Fig. K3 Keratoscope
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann