The color topography maps produced by these instruments usually give the shape of the cornea in diopters with each color corresponding to a given dioptric value. The dioptric change from one color to the next usually varies from one map to the next depending on the range of values for that cornea or the steps set by the operator. The data can be displayed in a number of ways with the different instruments.
The maps shown here are for a near spherical cornea, a toric cornea and a keratoconic patient.
See the module on the use and interpretation of computerized videokeratographers for more details on and its measurement.
