Efficacy of Intravitreal Levofloxacin 0.5% Ophthalmic Solution in Treating Pseudomonas Aeruginosa Endophthalmitis on a Rabbit Model

Purpose: To evaluate the efficacy of intravitreal levofloxacin 0.5% ophthalmic solution as treatment of Pseudomonas aeruginosa endophthalmitis in a rabbit model. Design: This is a parallel randomized experimental study. Methods: Twenty-six New Zealand white rabbits were enrolled. P. aeruginosa was inoculated intravitreally on the right eyes of all rabbits, which were further categorized into 2 groups, the treatment group (Group A) receiving 0.1 mL intravitreal injection levofloxacin 0.5% 24 hours after inoculation and the control group (Group B), which had 0.1 mL intravitreal aqua destilata (placebo). Clinical observation of the eyes in each group was performed on the first until the sixth day after the inoculation using clinical grading scale. On the sixth day, the eyes were examined for microbiological and histopathologic evaluations. Results: The total clinical grading scores of each group were similar 24 hours after P. aeruginosa inoculation (P > 0.05). The total clinical grading scores of Group A on the sixth day and the difference in total clinical scores on the first and the sixth day were shown to be significantly lower than that of Group B (P < 0.05). Microbiological analysis revealed that there was a lower bacterial count in Group A (mean = 1.18 ± 0.93 logCFU/0.1 mL) compared with Group B (mean = 4.09 ± 1.51 logCFU/0.1 mL), and the histopathologic scores of both groups were also significantly different (P < 0.05). Conclusions: Intravitreal levofloxacin 0.5% ophthalmic solution at 0.1 mL dose appeared to be effective in treating P. aeruginosa endophthalmitis in rabbits.