Effect of the Subconjunctival Injection of Oxytetracycline 5% on the Induced Alkali Burn Corneal Ulcer in Rabbits

Tetracycline had proven to be effective in the management of the different types of corneal ulcers. It has have antimicrobial activity as well as anti-collaginase effect. Therefore, the present study was conducted to investigate the effect of oxytetracycline 5% on the alkali burn ulcer after its injection subconjunctivaly. The drug was applied by subconjunctival injection in a dose of 0.5 ml once weekly for 5 weeks. Ten healthy New Zealand albino rabbits were divided into equal groups (control and treatment). They were examined carefully before induction of the ulcer using in 1% NaOH NaOH in the right eye. A 0.5 ml of oxytetracycline 5% was injected in the subconjunctival space weekly for 5 consecutive weeks. The eye was examined weekly clinically and by fluorescein staining dye just before the injection of oxytetracycline. At the end of the study, the rabbits were euthanized and the eyes were harvested for histological and electron microscopic examinations. The results revealed there were no significant variations between the control and treatment groups except for prevention of bacterial colonization on the ulcerated corneal surface in the oxytetacycline group. The conclusion of the present study was the subconjunctival injection of oxytetracycline was not efficient for management of alkali burn corneal ulcers, but it could be used as adjunctive treatment for control and prevention of bacterial growth on the ulcerated corneal surface.