Keratoscope
From Self-sufficiency
 | This article does not cite any references or sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (December 2009) |
This article is an orphan, as few or no other articles link to it. Please introduce links to this page from related articles; suggestions may be available. (December 2009) |
A keratoscope, sometimes known as Placido's disk, is an ophthalmic instrument for assessing the shape of the anterior surface of the cornea. A series of concentric rings are projected onto the cornea and their reflection viewed by the examiner through a small hole in the centre of the disk. A regular-shaped cornea should show equally-spaced symmetric reflections. If the patient is suffering from astigmatism or from a corneal dystrophy, the rings will be distorted.
A modern development of the concept is found in corneal topography, in which analysis of the reflected image is passed to a computer. The automated instrument can produce colour-coded contour maps of the eye's topology or even three-dimensional visualisations of its surface.
| 40x30px | This eye article is a stub. You can help ssf by expanding it. |
| 40x30px | This article related to medical equipment is a stub. You can help ssf by expanding it. |
