Posters

Fourier analysis of anterior and posterior corneal videokeratography data: clinical usefulness in keratoconus

Poster Details

First Author: V. Kozobolis GREECE

Co Author(s): H. Sideroudi   G. Labiris                 

Abstract Details

Purpose:

To evaluate the contribution of Fourier analysis of anterior and posterior corneal Videokeratographic Data in diagnosis of Subclinical Keratoconus (SKC) and Keratoconus (KC).

Setting:

Eye Institrute of Thrace, Democritus University, Alexandroupolis

Methods:

This was a cross-sectional, observational study. 80 eyes formed KC group, 55 eyes formed the SKC group while 50 normal eyes populated the control group (CG). Using Pentacam settings and a self-made code for Fourier series harmonic analysis, the anterior and posterior keratometric data on ring 1mm, 2mm, 3mm, 4mm were decomposed into spherical component, regular astigmatism, asymmetry and irregular astigmatism. The obtained values of both corneas surfaces were evaluated for their diagnostic capacity using receiver operating curves (ROC). Logistic regression was applied for identification of a combined diagnostic model.

Results:

For anterior and posterior corneal surface significant differences were detected in regular astigmatism, asymmetry and irregular astigmatism parameters among groups. Almost all parameters presented high diagnostic ability for both study group (AUC>90%). Concerning SKC group, among individuals parameters the highest predictive accuracy presented the regular astigmatism, irregular astigmatism and asymmetry (anterior: 90.9%-91.4% and posterior: 91.8%-95.8%). Higher predictive accuracy was identified using diagnostic models that combine the asymmetry, regular astigmatism and irregular astigmatism (anterior:99.4% and posterior: 100%).

Conclusions:

Fourier decomposition of anterior and posterior cornea Keratometric data provides parameters with high accuracy in differentiating SKC from normal corneas and should be included in the prompt diagnosis of KC.

Financial Disclosure:

None