International Journal of Keratoconus and Ectatic Corneal Diseases

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VOLUME 1 , ISSUE 2 ( May-August, 2012 ) > List of Articles


Topometric and Tomographic Indices for the Diagnosis of Keratoconus

Isaac Ramos, Fernando Faria Correia, Bernardo Lopes, Marcella Q Salomão, Rosane O Correa

Citation Information : Ramos I, Correia FF, Lopes B, Salomão MQ, Correa RO. Topometric and Tomographic Indices for the Diagnosis of Keratoconus. Int J Kerat Ect Cor Dis 2012; 1 (2):92-99.

DOI: 10.5005/jp-journals-10025-1018

Published Online: 01-08-2014

Copyright Statement:  Copyright © 2012; The Author(s).



To compare topometric (front surface curvature) and tomographic (3D corneal shape) indices for diagnosing keratoconus.


Pentacam data from one eye randomly selected of 200 normals (N) and 177 keratoconus (KC) were analyzed. Tomographic and topometric indices were tested. Receiver operating characteristic (ROC) curves were calculated, along with pairwise comparisons.


All tested variables had significant differences among N and KC (Mann-Whitney, p < 0.001). Most accurate tomographic indices had higher AUC than best topometric ones (DeLong, p < 0.05). Belin-Ambrosio D (BAD-D) had AUC of 1.00 (sensitivity 100.0%; specificity 98.5%).


Tomographic data was superior than topometric data to detect keratoconus. The BAD-D was an enhanced approach for detecting keratoconus.

How to cite this article

Correia FF, Ramos I, Lopes B, Salomão MQ, Luz A, Correa RO, Belin MW, Ambrósio R Jr. Topometric and Tomographic Indices for the Diagnosis of Keratoconus. Int J Kerat Ect Cor Dis 2012;1(2):92-99.

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