To Assess and Compare the Effect of Combination of Anti-Glaucoma Drug on Corneal Endothelium in Primary Glaucoma Patients with Age Matched Healthy Control

Abstract

Purpose: To compare the corneal endothelium changes in primary glaucoma patients on common combination of anti- glaucoma medications with healthy controls of the same age group. Material and Methods: A case control study which was conducted from January 2022 for a period of 12 months on 100 patients. The patients with primary glaucoma above 40 years of age on same combination of anti-glaucoma medications Brimonidine (0.2%w/v) and Timolol (0.5%w/v) )and their age matched healthy control were included in the study. Detailed slit lamp evaluation of all the patients were performed including visual acuity, Static perimetry Intraocular Pressure (IOP) measurement, indirect gonioscopy and fundus evaluation with +90 D, similar tests were performed in normal age matched controls as well. Additionally, specular bio microscopy was performed and the following parameters were assessed and compared with age matched normal control group. Endothelial Cell Density (ECD), Percentage of hexagonal cells (6A), Central Corneal Thickness (CCT), Coefficient of Variation (CV) in cell area were determined. All examinations were performed by the same examiner to avoid biasing. Result: It was observed that out of 50 glaucoma patients 36 patients (72%) were diagnosed as Primary Angle Closure Glaucoma (PACG) and 14 patients (28%) had Primary Open-Angle Glaucoma (POAG). Correlation between ECD loss, hexagonality, endothelial cell area and intraocular pressure was studied between case and control groups and glaucoma subgroups as well. IOP showed positive correlation with Coefficient of variation (CV) i.e.with increase in IOP value of CV increased . However, a negative correlation was found between IOP corneal ECD), hexagonality (6A) and CCT i.e., with increase in IOP the value of ECD ,6A and CCT decreased and vice versa. The average endothelial cell density was significantly decreased in glaucoma patients (1610 ± 225 cells/mm2) compared with the control group (2210 ± 236 mm2). Conclusion: The present study, suggest that use of antiglaucoma medications (Brimonidine 0.2% and Timolol0.5%) affect the metabolism of the corneal endothelium and cause pathological changes. Hence for primary glaucoma patients, quantitative analysis of corneal endothelial cells morphology is necessary, despite the well-established benefits of antiglaucoma medications in reducing Intraocular Pressure (IOP), the potential impact of these drugs on the corneal endothelium remains a concern.