Oxygen Therapy for Severe Corneal Alkali Burn in Rabbits

Abstract

To evaluate the efficacy of oxygen therapy in the treatment of severe corneal alkali injury in rabbits. In a double-blind experiment, 28 white New Zealand rabbits were randomized into an oxygen treatment group (n = 14) and a control group (n = 14). Under general anesthesia, severe corneal alkali injuries were induced by application of 1 N sodium hydroxide to the right eye of each rabbit. The oxygen treatment group was treated with oxygen 100% at a flow of 5 L/min for 1 hour daily for 1 month. Daily photographs were taken of the rabbits' eyes, and the sizes of the epithelial defect in the 2 groups were compared. The principal endpoint was descemetocele and perforation of the cornea. The animals were euthanized at the end of the study or earlier if corneal perforation had occurred, and the corneas were excised and fixed in 10% neutral-buffered formalin for histologic examination. Experimentally induced severe eye burns gave similar opacity of the cornea in both groups. Three eyes in the oxygen group and 9 eyes in the control group developed descemetocele and perforation (P = 0.022). Mean time to beginning of ulceration was 13.45 days in the control group and 18.11 days in the oxygen treatment group (P = 0.032). There was no other significant difference between the 2 groups. Oxygen therapy at a flow of 5 L/min for 1 hour daily reduces the possibility of corneal perforation in rabbits and may delay ulceration of the cornea compared with the control group.