Corneal endothelial cell density and pterygium: a cross-sectional study
ABSTRACT Purpose: To investigate the effects of pterygium on corneal endothelial cell density in patients with unilateral pterygium. Methods: We performed a cross-sectional analysis of data from patients with unilateral pterygium who were selected from September 1, 2015 to July 31, 2016 at Hospital de Base do Distrito Federal to assess the corneal endothelial cell density, coefficient of variation in the cell area, hexagonality, and corneal pachymetric results. In all patients, noncontact specular microscopy was performed in both eyes and a minimum endothelial cell count of 75 cells/mm2 was required for inclusion in the study. The contralateral eye served as the control. Results: Sixty-one patients were included in the study. Twenty-nine (47.5%) patients were men and 32 (52.5%) were women (mean age, 50.84 ± 13.8). The percentage of pterygium that invaded the cornea ranged from 4.87% to 24.59% (median, 9.70% ± 4.99%). The mean corneal endothelial cell density (cells/mm) was lower in the pterygium eyes than in the controls (2451.83 ± 284.96 vs. 2549.95 ± 268.94, respectively; p=0.04). No differences in the mean coefficients of variation of cell size, hexagonality, and corneal pachymetric results were observed between the patients and controls. The Pearson correlation test showed a significant negative linear relationship between pterygium invasion and endothelial cell density [p<0.001, n=61, r=-0.553 (95% CI, -0.34 to -0.73)]. Conclusion: Compared with the contralateral eyes, those of patients with unilateral pterygium were associated with a decrease in corneal endothelial cell density.