[Central corneal thickness and corneal endothelial morphology with and without therapy using commercially available antiglaucomatous drugs].

PURPOSE: The aim of this study was to investigate the influence of antiglaucomatous medications on central corneal thickness and corneal endothelium.
MATERIAL AND METHODS: Data of patients referred for glaucoma diagnostics and therapy with an open-angle situation were extracted from a database and evaluated with respect to central corneal thickness (CCT), corneal endothelial cell density (CD [mm(-2)]), cell variation (CV; standard deviation of cell size/average cell size), and quantity of hexagonal endothelial cells (6A). Data from patients without or under therapy with commercially available pharmaceuticals (metipranolol 0.3%, timolol 0.5%, dorzolamid, brinzolamid, brimonidine, bimatoprost, travoprost, and latanoprost) were compared statistically using Mann-Whitney and Kruskal-Wallis tests with post-tests (α = 0.05): No therapy vs. antiglaucomaous therapy, no therapy vs. number of antiglaucomatous substances (0, 1, 2), no therapy vs. groups of medications (ß-blockers [BB], carboanhydraseinhibitors [CAI], and prostanglandin agonists [PGA]), single preparations.
RESULTS: Age, mean defect in the 30 - 2 threshold test (Humphrey), and intraocular pressure (IOP) were not correlated with the parameters tested. Significant differences were found between the groups of treated vs. untreated patients for CCT, CD, and CV. CCT, CD, and CV showed significant differences between untreated patients and monotherapy as well as dual therapy (two substances in one drug). The comparison of groups of substances (no therapy, BB, CAI, and PGA) revealed a statistically significant reduction of CCT under treatment with PGA. CD differed significantly between no treatment and a combined therapy with timolol plus brinzolamide. Comparing individual pharmaceuticals the most important results were significant differences between timolol plus travoprost vs. the other groups except for bimatoprost and latanoprost and PGAs vs. not preserved eye drops.
CONCLUSIONS: Corneal endothelial morphology showed a significant reduction of CD under therapy with BB compared to the no-treatment group. As this was not found on comparing individual medications, it could be a statistical phenomenon of larger counts and thus of secondary clinical concern. Significant differences of CCT were found with antiglaucomatous medications. When adjusting Goldmann tonometry with pachymetry this should be taken into account in order to prevent a misinterpretation of the therapeutic effects of locally applied eye drops. © Georg Thieme Verlag KG Stuttgart · New York.