Abstract

PURPOSE:

To assess the effects of dorzolamide hydrochloride, a topical carbonic anhydrase inhibitor, on corneal endothelial function.

METHODS:

The authors measured the rate of corneal deswelling and the endothelial permeability to fluorescein after 2 hours of hypoxic contact lens wear in 19 normal human subjects. The study was double-masked; one eye of each subject was randomly assigned to receive 2% dorzolamide drops, and the other eye received placebo drops every 8 hours for 24 hours before the study day and twice during the study day.

RESULTS:

Dorzolamide-treated eyes were not significantly different from placebo-treated eyes in corneal deswelling rate, expressed as the percent recovery per hour (55.7% +/- 13.6% versus 59.6% +/- 14.5%; P > or = 0.10), open eye steady state thickness, swelling induced by hypoxia, and corneal autofluorescence. Endothelial permeability to fluorescein was increased in the dorzolamide eyes (4.40 +/- 0.84 x 10(-4) cm/minute versus 4.10 +/- 0.80 x 10(-4) cm/minute; P = 0.01). As expected, the intraocular pressure and aqueous humor flow rate were decreased in the dorzolamide eyes.

CONCLUSIONS:

Dorzolamide hydrochloride, when topically administered to normal human eyes for 24 hours, had no significant effect on the corneal deswelling rate after hypoxic stress. The corneal endothelial permeability to fluorescein, however, was increased by the drug, although this did not result in increased corneal thickness.