Posters

Deviation of different points for keratoconus localisation

Poster Details

First Author: G.Steinwender AUSTRIA

Co Author(s):    A. Kollenc   M. Sommer   W. Glatz   J. Horwath-Winter   M. Shajari   T. Kohnen     

Abstract Details

Purpose:

Exact topographical determination of keratoconus localization is gaining in importance, as new diagnostic methods (e.g. Belin-Ambrosio enhanced ectasia display) and treatment options (e.g. customized corneal cross-linking) are based on the center of the ectatic corneal region. Therefore, the aim of the study was to compare different parameters like steepest curvature of anterior sagittal (Kmax) and tangential map (tKmax), thinnest point (TP), and maximum anterior (MAE) and posterior elevation (MPE) for keratoconus localization.

Setting:

Medical University Graz, Austria

Methods:

Scheimpflug measurements (Pentacam) of 164 eyes of patients who have been diagnosed with keratoconus were retrospectively analyzed. Coordinates of Kmax, tKmax, TP, MAE, and MPE were determined and the distances between those locations were calculated. Eyes were divided in 2 groups upon the topographic keratoconus classification (group 1 for stage 1 and 2, group 2 for stage 3 and 4) to compare the calculated distances between those 2 groups.

Results:

The smallest distances were detected between MAE and MPE (0.37 ±0.44 mm), followed by MAE and tKmax (0.64 ±0.46 mm), and MPE and tKmax (0.65 ±0.46 mm). Eighty eyes were included in group 1, and 84 eyes in group 2. Although distances between different points of keratoconus localization were higher in group 1, statistical significance was only reached in the distances between TP and Kmax (p=0.005), MPE and Kmax (p=0.002), and Kmax and tKmax (p=<0.001).

Conclusions:

There are deviations between different points of keratoconus localization, more pronounced in eyes with less advanced stages of disease. The smallest deviations were found between MAE, MPE, and tKmax. Therefore, these points seem to be the most accurate to determine the center of a keratoconus.

Financial Disclosure:

None