Short-term effect of dorzolamide hydrochloride on central corneal thickness in humans with cornea guttata.

OBJECTIVE To investigate the short-term effect of dorzolamide hydrochloride, a topical carbonic anhydrase inhibitor, on central corneal thickness in patients with cornea guttata. DESIGN AND METHODS In this randomized, placebo-controlled, double-masked, 3-drug crossover study, 20 patients with cornea guttata (mean endothelial cell count, 1321 cells/mm2) and 8 healthy control subjects (mean endothelial cell count, 2483 cells/mm2) were included. Study medications included 2% dorzolamide hydrochloride (Trusopt 2% eye drops; Merck & Co Inc, Whitehouse Station, NJ), 0.9% saline solution (saline placebo), and a solution identical to the carrier substance of dorzolamide in Trusopt (carrier placebo). The study drugs were applied 4 times per day for 1 day only. Central corneal thickness measurements were performed using partial coherence interferometry on every study day at baseline and after 24 hours of study medication treatment. MAIN OUTCOME MEASURES Change in central corneal thickness. RESULTS The mean thickening in central corneal thickness within 24 hours in eyes with cornea guttata treated with dorzolamide, saline placebo, and carrier placebo was 12.0 micro m (95% confidence interval [CI], 7.0-17.1 microm), 0.6 micro m (95% CI, -1.0 to 2.2 microm), and 1.3 micro m (95% CI, -0.1 to 2.6 microm), respectively. CONCLUSION Application of dorzolamide for 1 day results in a slight but statistically significant thickening of central corneal thickness in patients with cornea guttata.