Comparison of Scheimpflug imaging parameters between steep and keratoconic corneas of Caucasian eyes

PURPOSE To compare the keratometric and pachymetric parameters of healthy eyes with those affected by steep cornea and keratoconus (KC) using Scheimpflug camera. SETTING Briz-L Eye Clinic, Baku, Azerbaijan. DESIGN A cross-sectional study. METHODS In this study, 49 KC (Amsler-Krumeich stage 1) eyes and 36 healthy eyes were enrolled. A complete ophthalmic evaluation and a Scheimpflug camera scan were performed in every eye included in the study. Tomographic parameters such as parameters from the front and back cornea, maximum keratometry reading (Kmax), corneal volume (CV), anterior chamber volume (ChV), anterior chamber depth (ACD), anterior chamber angle (AC angle), keratometric power deviation (KPD), maximum front elevation (Max FE), and maximum back elevation (Max BE), as well as pachymetric progression indices (PPI), Ambrosio relational thickness (ART), index of surface variance (ISV), index of vertical asymmetry (IVA), center keratoconus index (CKI), index of height asymmetry (IHA), index of height decentration (IHD), and radius minimum (RM) were collected and statistically compared between the two groups. RESULTS PPI, ART, ISV, IVA, CKI, IHA, IHD, and RM parameter values were significantly different (P<0.05) between the KC and healthy eyes. There were no significant differences in K mean and Q values of the frontal corneal parameters, as well as in Kmax, AC angle, RM, back, and front astigmatism, between stage 1 keratoconic and normal Caucasian eyes with steep cornea. All other parameters such as K mean and Q values of the back corneal parameters, Max FE, Max BE, ACD, ChV, and CV showed significant differences between the groups (P<0.05 for all). CONCLUSION Scheimpflug imaging is able to detect corneal morphological differences between stage 1 KC eyes and healthy eyes with steep cornea, in Caucasians.