Short-term effect of intracameral triamcinolone acetonide on corneal endothelium using the rabbit model

Purpose To investigate the effect of intracameral injection of triamcinolone acetonide on the corneal endothelium in rabbit eyes. Methods Triamcinolone acetonide ( 40 mg/ml, 0.2cm(3)) after filtering and resuspension in balanced salt solution ( BSS) was injected intracamerally for 3 min into 10 rabbit eyes and irrigated with 5 cm 3 of BSS. Triamcinolone without resuspension and BSS were injected, respectively, into five rabbit eyes. Endothelial toxicity was evaluated and compared by measurements of endothelial cell counts and central corneal thickness. The endothelial viability was determined using vital staining with alizarin red and trypan blue at 2 h after injection. The scanning electron microscopy ( SEM) was performed in one cornea from each group. Results Endothelial cell counts and central corneal thickness following intracameral injection of triamcinolone acetonide did not significantly change when compared to controls. The mean percentage of viable endothelial cells was 99.50, 99.52, and 99.49% in the resuspended triamcinolone group, triamcinolone without resuspension group, and BSS group, respectively ( P = 0.46, Kruskall-Wallis test). But SEM showed reduced microvilli of endothelial surface in an eye of the triamcinolone without resuspension group. Conclusions The intracameral injection of triamcinolone acetonide did not induce a significant visable change of endothelium in rabbit eyes. However, ultrastructural villi changes observed suggest a possibility of microstructural damages in endothelium with triamcinolone acetonide injection when used without filtering and resuspension.