Abstract
Purpose :
To evaluate a matrix mathematical method based on elevation data topography by comparing the pattern observed in normal controls and keratoconus diagnosed patients.
Methods :
37 keratoconus diagnosed patients (based on clinical examination and commonly used indices) and 36 age-matched normal controls were included (10-40 years old). Complete ophthalmological evaluation, including refraction, automated keratometry, and Pentacam corneal topography in both eyes were carried out in a cross-sectional study. Mean square (6 mm side) matricial data derived from elevation based topography and centered on the corneal apex were compared between keratoconus and controls. Specific eccentric mean matricial data of two additional patches in different locations of the cornea were also compared. Each keratoconus subject was compared with mean matricial data of control subjects to determine its applicability in the diagnosis of keratoconus, using both central and eccentric matricial patches.
Results :
Central square matrix was not significantly different between controls and keratoconus patients, except for the last three inferior rows. The two different eccentric matrices were significantly different in keratoconus vs control subjects (p < 0.01). Individuals diagnosed of keratoconus showed central square matrix pattern within the limits of controls, but eccentric matrix patterns were outside the limits of control subjects (sensitivity 91.8% and 97.3%; specificity 94% and 97.2%, respectively, for the two eccentric patches).
Conclusions :
Elevation data matrix may be useful in the diagnosis and early detection of keratoconus, and in the evaluation of normal corneas.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.