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Published on: November 12, 2015
Tangential vs sagittal videokeratographs in the "early" detection of keratoconus
1Cornea-Genetic Eye Medical Clinic, Cedars-Sinai Medical Center, Los Angeles, CA, USA. rabinowitzy@csmc.edu
Purpose:
To illustrate the difference between tangential and sagittal videokeratographs in the "early" (subclinical) detection of keratoconus.
Methods:
The clinically normal fellow eye of a patient with unilateral keratoconus was studied with a topographer, which can display both a sagittal and a tangential map on the same page using the same color scale.
Results:
The tangential map depicted a pattern more consistent with keratoconus and provided a maximum power of 51 diopters compared with the 46 diopters of the sagittal map.
Conclusions:
Tangential videokeratographs, derived from instantaneous radius of curvature algorithms, may be more useful than sagittal displays for detecting subtle corneal topographic abnormalities.
