Posters

A study for volume-geometric operators to assist detection in early keratoconus with normal vision

Poster Details

First Author: L.Bataille SPAIN

Co Author(s):    F. Cavas-Martinez   D. Fernandez-Pacheco   J. Velazquez   J. Bolaren   J. Alio        

Abstract Details

Purpose:

To define new volumetric parameters and evaluate their potential for early keratoconus detection.

Setting:

Vissum Corporation, Alicante, Spain. Technical University of Cartagena, Spain.

Methods:

Comparative study including 310 eyes of 310 patients (age: 17-69 years). Two groups of eyes were differentiated: control group (148 healthy eyes) and early keratoconus group (162 eyes). A morphogeometric modeling of the cornea was performed using raw topographic data (Sirius system, CSO, Firenze) and the following corneal volume parameters were calculated: VOLmct, defined by the points of minimal thickness; VOLaap, defined by the anterior corneal apex, and VOLpap, defined by the posterior corneal apex. All the volumes were calculated for radius of the revolution cylinder ranging from 0.1 to 1.5 mm.

Results:

Significantly lower values of VOLmct, VOLaap, and VOLpap were found in early keratoconus groups (p<0.001). A logistic regression analysis revealed that the detection of early keratoconus was related to spherical equivalent, coma root mean square (RMS), spherical aberration, spherical-like RMS and VOLaap (R2 Nagelkerke: 0.887). The overall percentage of cases correctly classified by the model was 95.2%.

Conclusions:

A reduction of corneal volume in early keratoconus is detected. The combination of optical and volumetric data allows an accurate detection of incipient cases.

Financial Disclosure:

None