EFFECT OF INTRAVITREAL DEXAMETHASONE IN TREATMENT OF PNEUMOCOCCAL ENDOPHTHALMITIS IN RABBITS

Purpose: To investigate whether corticosteroid therapy would decrease the inflammation and tissue damage associated with pneumococcal endophthalmitis. Methods: Albino rabbits were injected intravitreally with 1000 live organisms of Streptococcus pneumoniae and randomized after 24 hours to treatment with intravitreal vancomycin hydrochloride alone (n=10), combination intravitreal vancomycin and intravitreal dexamethasone (n=10), or no treatment (n=10). After 2 weeks, the eyes were examined clinically and enucleated for histopathologic examination. Results: Eyes treated with vancomycin and dexamethasone had significantly less intraocular inflammation and more preservation of retinal tissue than untreated eyes or eyes treated with vancomycin alone (P<.05, Fisher's exact test). Untreated and vancomycin-treated eyes were indistinguishable on clinical and histologic examination. Marked anterior and posterior segment inflammation with total retinal necrosis was noted in eyes from both groups. Conclusion: Intravitreal corticosteroid therapy may play an important role in minimizing the inflammation and tissue damage associated with pneumococcal endophthalmitis.