Corneal Endothelial Protection of Ascorbic Acid against Free Radicals during Phacoemulsification

Suh, Young Woo; Oh, Chung Hoon; Kim, Hyo Myung

Abstract

PURPOSE
To evaluate corneal endothelial protection effect of ascorbic acid (AA) at the most appropriate concentration, and determine the synergistic effect of glutathione in irrigation solution during phacoemulsification. METHODS: Phacoemulsification was performed in the anterior chamber of 30 rabbit eyes for 5 minutes without damage to other ocular structures. Thirty rabbit eyes were divided into 6 groups, of 5 eyes each, according to the following irrigation solutions in phacoemulsification.: BSS(R) in group 1, BSS(R) with 1 mM AA in group 2, BSS Plus(R) in group 3, BSS Plus(R) with 0.1 mM AA in group 4, BSS Plus(R) with 1 mM AA in group 5 and BSS Plus(R) with 10 mM AA in group 6. Corneal endothelial loss was measured with specular microscopic photographies taken before and 1 week after surgery. RESULTS: Postoperatively endothelial counts were reduced by 592.0 +/- 100.0, 275.9 +/- 51.9, 658.2 +/- 107.1, 466.3 +/- 88.6, 259.3 +/- 61.6 and 451.6 +/- 63.7 (mean cells/mm2 +/- SD) in groups 1-6, respectively. Endothelial cells in group 2 were less reduced than in group 1 (P=0.009), but there was no difference between groups 2 and 5. Though the reduction of endothelial cells in groups 4, 5, and 6 were less than in group 3 (P<0.05), group 5 showed more significant endothelial protection effect than groups 4 and 6 (P=0.009, 0.009). CONCLUSIONS: AA in irrigation solution showed endothelial protection effect against free radicals during phacoemulsification, and 1 mM was the most effective concentration. Combination of glutathione with AA did not show any synergistic endothelial protection effect.