Keratoscope (Placido's disc)
A keratoscope is also known as (a) "Placido's Disc".
A keratoscope is not itself an ophthalmic
procedure but it is included in this section of terms about ophthalmic
procedures because a keratoscope is used for diagnosis or assessment
prior to, and / or sometimes after, some ophthalmic procedures.
That this term concerns the cornea of the eye is indicated by the part of the term "kerato-" which refers to the cornea of the eye, and is also applied to other terms in this section - listed on the left.
A keratoscope is an ophthalmic instrument for detecting abnormal curvature of the the cornea of the eye. It consists of a black disc that is marked with concentric white rings at whose centre is a small lens through which the ophthalmologist can observe the patient's cornea. When using this device the practitioner observes the reflections of the white rings in the patient's cornea. In the case of a normally-shaped cornea, those reflections are also a set of concentric rings. If the reflections appear to be non-circular, treatment might be recommended.
More about Ophthalmology:
This section includes short definitions
of many diseases, disorders, and conditions of the eyes and visual system.
For definitions of other terms in this category, choose from the list to the left (but note that this is not a complete/exhaustive list).
Other related pages include
- A diagram of the eye
- Definitions and descriptions of the parts of the eye
- A concise description of the human retina
- Definitions of parts of the retina
- Diseases and disorders of the human eye and the human visual system
For further information see also our pages of books about ophthalmology.