Influence of Keratoconus Severity on Detecting True Progression with Scheimpflug Imaging and Anterior Segment Optical Coherence Tomography

To determine consistent change over time in keratoconus disease, it is necessary to establish progression cut-off values based on intersession variability of the device used monitor cornea. The aim this study was analyze accuracy corneal parameters using Scheimpflug tomography and anterior segment optical coherence healthy keratoconic eyes varying severity that indicate real progression. Three repeated measurements each cornea (20 eyes) (mild = 16, moderate 25 severe 20) were recorded Pentacam Casia SS-1000 devices, which 2–3 weeks later. K1, K2, maximal posterior keratometry, thickness at thinnest location (TCT) collected. excellent with both devices; however, presented better repeatability reproducibility all groups compared Pentacam. mild stage lower (K1 0.50 0.37 D; K2 0.51 Kmax-A 1.24 0.65 Kmax-P 0.38 0.17 TCT 19.64 11.19 µm) than 1.09 0.88 1.41 0.87 2.74 2.15 0.82 0.22 28.68 14.83 µm). These results show greater severity, must occur for be considered real.