Posters

Correlation between corneal biomechanical indices and severity of keratoconus

Poster Details

First Author: S.Koh JAPAN

Co Author(s):    R. Inoue   R. Ambrósio Jr   N. Maeda   K. Nishida           

Abstract Details

Purpose:

Corneal biomechanical analysis is highly sensitive to distinguish clinical keratoconus (KC) eyes from normal healthy eyes. However, the correlation between corneal biomechanical indices and severity of KC are unknown. The purpose of the study is to compare the biomechanical indices from Scheimpflug-based corneal biomechanical assessments in patients with asymmetric KC and investigate the relationship between these indices and the severity of KC.

Setting:

Osaka University Hospital, Osaka, Japan

Methods:

Fifty-eight patients who presented with clinical KC in one eye and mild  KC in the fellow eye were included. The mild KC eyes had abnormal topography based on Klyce/Maeda and Smolek/Klyce indices without slit-lamp findings of KC. Corneal tomographic and biomechanical assessments were accomplished by Pentacam HR and Corvis ST (Oculus GmbH). The following parameters were compared between the clinical and mild KC eyes: deformation amplitude max 2mm (DAmax), integrated radius, Ambrósio relational thickness to the horizontal profile (ARTh), and stiffness parameter at first applanation (SPA1).The relationship between biomechanical indices and maximum keratometry (Kmax)/thinnest pachymetry reading (Tmin) were analyzed

Results:

DAmax and integrated radius were significantly higher (p<0.001, p<0.001), and  ARTh and SPA1 were significantly lower in KC eyes than in mild KC eyes (p<0.001, p<0.001). Significant positive correlations between Kmax and DAmax (r=0.746, p<0.001) and Kmax and integrated radius (r=0.728, p<0.001). Significant negative correlations between Kmax and ARTh (r=-0.725, p<0.001) and Kmax and SPA1 (r=-0.641, p<0.001). Significant negative correlations between Tmin and DAmax (r=-0.658, p<0.001) and Tmin and integrated radius (r=-0.654, p<0.001). Significant positive correlations between Tmin and ARTh (r=0.716, p<0.001) and Kmax and SPA1 (r=0.708, p<0.001).

Conclusions:

Corneal biomechanical indices correlated well with disease severity and with corneal shape parameters such as Kmax and thinnest pachymetry in KC and mild KC eyes. This work supports the possibility for developing a biomechanically-based staging classification for KC.

Financial Disclosure:

... gains financially from product or procedure presented