Summary
Contact wide-field specular microscopy was performed on eyes of 16 healthy dogs after tissue plasminogen activator at a concentration of 25 μg/100 μl (group 1, n = 8) or 50 μg/100 μl (group 2, n = 8) was injected into 1 anterior chamber of each dog. The contralateral eye served as a nontreated control. Applanation tonometry was used to measure intraocular pressure in both eyes for up to 168 hours. By use of computerized morphometric analysis and pachymetry, changes from baseline values in endothelial cell density, cell morphologic features, and corneal thickness were evaluated at postinjection hours 24, 48, and 168. Significant mean differences in intraocular pressure were not detected between treated eyes of group-1 dogs and those in group 2 at designated times, or between treated and nontreated eyes of dogs in either group. Mean corneal thickness of treated and nontreated eyes was similar in both groups through postinjection hour 168. Changes in mean percentage of endothelial cell sides were observed only in treated eyes of group-2 dogs, with the mean percentage of hexagons at postinjection hour 168 decreasing by 18%, a decrease that was significantly (P < 0.05) greater than the decrease in nontreated eyes. The mean percentage of 6-sided cells in treated eyes of group-2 dogs was significantly (P < 0.05) less than that in treated eyes of group-1 dogs at postinjection hour 168.
