Corneal posterior surface characterization in normal and keratoconus patients according to the degree of visual limitation

Session Details

Session Title: Cornea Medical I

Session Date/Time: Monday 12/09/2016 | 17:00-18:30

Paper Time: 17:42

Venue: Hall C2

First Author: : A.Vega-Estrada SPAIN

Co Author(s): :    P. Sanz Diez   J. Alio                 

Abstract Details

Purpose:

To describe and analyze the main features of the corneal posterior surface in normal and keratoconus patients taking into account the severity of the visual function.

Setting:

Vissum, Alicante, Spain.

Methods:

Retrospective, clinical study evaluating 477 eyes. All patients were classified according to the degree of the visual limitation as follows: normal group: patients with corrected visual acuity (CDVA) of 1,000 in the decimal scale; grade I, CDVA between 0,900 and 0,980; grade II, CDVA between 0,600 and 0,880; grade III, CDVA between 0,400 and 0,580; grade IV, between 0,200 and 0,380 and grade Plus, less than 0,200. All patients were evaluated using rotating Scheimpflug camera and Placido disc topographer device (Sirius system, CSO, Firenze, Italy).

Results:

A significant difference were found in all pair of groups, including normal and keratconic patients, when evaluating the mean steepest posterior keratometric reading (K2) at 3 and 5 millimeters (p ≤ 0,03) and the root mean square per area unit (RMS/A) at 4,5 and 8 mm (p ≤ 0,01). Additionally, a high and statistically significant difference was observed between normal and grade I keratoconus patients when analyzing K2 at both 3 and 5 mm (p< 0,01). No significant differences were found when comparing the most severe grades (IV and Plus) in terms of K2 and RMS/A (p > 0.100).

Conclusions:

Corneal posterior analysis in normal and keratoconus patients correlated well with the degree of visual limitation. Posterior keratometry and root mean square per area unit allow us to discriminate between normal and keratoconus patients and also to characterize the severity of the disease according to the visual impairment.

Financial Disclosure:

NONE