A correlation study between a corneal endothelial count in patients with different stages of keratoconus using specular microscopy

ABSTRACT Objective: To evaluate the corneal endothelial count in patients with keratoconus (KCN) by specular microscopy and correlate with the stage of keratoconus. Methods: Ninety-three eyes from 61 patients with KCN were included in this cross-sectional study. The eyes were classified into KCN stages 1 to 4 according to the Amsler-Krumeich classification using keratometry obtained by corneal topography and pachymetry readings obtained by specular microscopy. Results: Age ranged from 12 to 43 years, mean ± (standard deviation) 22.1 ± 6.7 years. The average keratometry ranged from 42.25 to 71.4 D, (53.0 ± 6.1 D). Pachymetry ranged from 350 to 606 µm, (461.7 ± 47.1 µm). Regarding the Amsler classification, 23 patients (24.7%) had stage 1, 24 (25.8%) stage 2, 5 (6.5%) stage 3 and 41 patients (44.1%) stage 4. No linear correlation was observed between mean keratometry and endothelial cell count (Pearson's correlation coefficient = -0.05). In the early to moderate stages of KCN, the mean endothelial cell count was 2738.3 ± 285.4 cell / mm2, while in the advanced KCN group (stages 3 and 4) it was 2670.6 ± 262.7 cell / mm2 , p = 0.24. Conclusions: No correlation was found between the endothelial cell count and the KCN stage.