Purpose: To evaluate and correlate corneal endothelium parameters with the severity of primary glaucoma.
Methods: This prospective case-control study was conducted on 150 eyes of 80 newly diagnosed primary open-angle glaucoma (POAG), chronic primary angle-closure glaucoma (cPACG), and normal-tension glaucoma (NTG) patients in a tertiary care center. Endothelial parameters including endothelial cell count (ECC), percentage of hexagonal cells, and coefficient of variation of cell size were analyzed. Glaucoma cases were further sub-grouped into early, moderate, and severe glaucoma and compared for endothelial parameters. Chi-square, Fischer's exact test, independent sample t-test, and analysis of variance were performed using IBM® SPSS® Statistics version 28.
Results: The ECC was markedly reduced in cases (2281 cells/mm2) versus controls (2611 cells/mm2) (P < 0.001). The POAG (2251 cells/mm2) and cPACG (2287 cells/mm2) eyes had significantly a lower ECC compared to healthy controls (P < 0.001), whereas NTG eyes had a lower mean ECC (2538 cells/mm2), but it was not statistically significant (P > 0.05) when compared with controls. The ECC decreased with an increase in severity as patients with early glaucoma had an ECC of 2284 cells/mm2, moderate 2261 cells/mm2, and severe 2086 cells/mm2, and the difference was statistically significant.
Conclusion: A significant decrease in corneal ECC was observed in POAG and cPACG patients when compared with healthy controls of the same age group. Mechanical damage following an elevated intra-ocular pressure for a longer duration may be attributed to morphological and consequent functional damage to endothelial cells.
Keywords: Chronic primary angle-closure glaucoma; endothelial cell density; intra-ocular pressure; normal-tension glaucoma; primary open-angle glaucoma.