Changes in confocal microscopy in glaucoma patients after intraocular pressure reduction with medical therapy

Abstract

Purpose: Topical glaucoma medication is the first line of management to reduce intraocular pressure (IOP) in patients with glaucoma. In this study, we intended to compare the ultrastructural findings of the cornea in patients with glaucoma before and after the reduction of the IOP through confocal microscopy. Methods: Ten patients (19 eyes) with newly diagnosed glaucoma were recruited from the glaucoma services of our tertiary care center. Demographic parameters were noted, and basic ocular examination, specular microscopy (Topcon SP3000P, Tokyo, Japan), and ultrasonic pachymetry (300 AP, Sonomed Escalon, Stoneham, MA, USA) were performed. In vivo confocal microscopy of corneal sections was performed using the z-ring Confoscan 4.0 (Nidek, Inc., Freemont, CA) at baseline and after 3 months of starting glaucoma medications. Results: The mean age of the patients was 53.53 ± 9.34 years. There was a statistically significant reduction (P < 0.0001) of IOP from 30.21 ± 7.42 mmHg (baseline) to 16.42 ± 4.14 mmHg (3 months). The mean central corneal thickness at baseline was 533.42 ± 3.96 µm, and it further decreased to 521.94 ± 42.45 µm at the end of 3 months (P = 0.006). No significant change was noted in the mean epithelial cell density, mean keratocyte density in anterior and posterior stroma, and the mean endothelial cell density and cell area (P >0.5). There was no significant percentage change in these parameters before and after the lowering of the IOP. Conclusion: A short-term (3 months) decrease in IOP using topical glaucoma medications caused a significant reduction in corneal thickness but did not have any significant ultrastructural changes in cornea measured using confocal microscopy.