The Cornea and Corneal Topography
The cornea is the clear tissue in front of the iris (the coloured part of the eye) and the pupil. It plays a critical optical role and also protects the eye from infection, dust and other harmful particles.
Because the cornea and the tear film that it supports is the first structure that light passes through before coming to a focus at the back of the eye, any irregularities in the corneal surface can result in significantly reduced vision.
Corneal topography provides a 3-D map of the front corneal surface. This enables us to see the characteristics of its curves and to detect any surface irregularities - important for diagnosing conditions such as astigmatism, keratoconus, pellucid marginal degeneration and other rare corneal conditions.
Images from the corneal topographer are used for orthokeratology and for fitting other rigid gas permeable (hard) contact lenses.