Effect of intravitreal dexamethasone in treatment of pneumococcal endophthalmitis in rabbits
S. S. Park, N. Samiy, K. Ruoff, D. J. D'Amico and A. S. Baker
Department of Ophthalmology, University of Texas, Southwestern Medical Center, Dallas, USA.
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.
