COMPUTERIZED VIDEOKERATOSCOPESDATA DISPLAY

Difference Maps

A common use of the videokeratoscopes is to follow changes in the corneal curvature over time such as with adaptation to contact lenses, changes with orthokeratology, progression of keratoconus or following corneal surgery.  

The software with the instruments allow two images to be subtracted so that the difference between the two maps can be displayed.  This allows for a quick analysis 
of the difference between 
two readings.  In this case 
the dioptric values 
represent the difference 
between the maps.

The difference map can be 
displayed by itself or along 
with the original maps.