Corneal endothelial density: An indicator for primary glaucoma progression

Abstract

Purpose: Glaucoma is a progressive optic neuropathy causing death of retinal ganglion cells and their axons resulting in visual morbidity. This study was aimed to evaluate the impact of primary glaucoma on retinal nerve fiber layer (RNFL) thickness and corneal endothelial damage and to establish any correlation between these two. Materials and Methods: A total of 104 patients (179 eyes) diagnosed as primary open-angle glaucoma (POAG), primary angle-closure glaucoma (PACG), and normotensive glaucoma (NTG) were included in this study. Secondary glaucoma, postviral infection, ocular trauma, ocular surgery, and diabetes mellitus were criteria for exclusion. Average retinal nerve fiber layer (AvRNFL) thickness and endothelial cell count (cell density [CD]) were measured. Statistical analysis was done using Spearman's correlation coefficient. Results: The AvRNFL thickness in POAG (n = 120) was 83.83, PACG (n = 46) was 81.45, and Normotensive (NTG) (n = 13) was 71.07 μ. The mean CD values were 2416.68 cells/mm2, 2622.543 cells/mm2, and 2482.69 cells/mm2, respectively. A significant positive correlation between these two values was observed in POAG (P = 0.004) but not seen in PACG or NTG. Conclusion: Corneal endothelium loss may be an indicator of disease progression and RNFL thinning in patients of POAG. Routine specular microscopy evaluation of these patients can be helpful, and low endothelial counts indicate RNFL damage.