Abstract
Purpose: :
Enterococcus faecalis
Methods: :
Fifty-four Japanese albino rabbits underwent phacoemulsification and aspiration of the left eye, and 1×104colony-forming units (CFU) of E. faecalis OG1S (secreted protease-positive) were inoculated into the lens bag. One group of eyes received intravitreal injection of saline 6 hours after inoculation (VCM(-)), and four other groups received intravitreal injection of VCM (1mg/0.1ml) 6, 12, 18, or 24 hours after inoculation. Clinical scores for endophthalmitis (0-4) were recorded and the electroretinogram (ERG) was monitored over the course of the infection. Forty-eight hours after inoculation, the eyeballs were enucleated. The pathology of each group of eyes was compared and the bacteria in the aqueous humor and vitreous cavity were quantified (log10 CFU/tissue).
Results: :
Pathological examination revealed that groups which received intravitreal VCM earlier tended to show less inflammatory cell infiltration and tissue damage. The average endophthalmitis scores and reduction of ERG b-wave amplitudes (test/control eye ratio, %) in the 6 hour VCM(+) group (2.25, 138.0, respectively) improved significantly compared to those of the VCM (-) group (3.60, 39.7, respectively) (p<0.01). There was significantly less bacterial growth in the aqueous humor in the VCM(+) groups (1.25, 1.09, 2.80, and 2.86, for 6, 12, 18, and 24 h) compared to the VCM(-) group (5.74). In the vitreous body, bacterial growth in the 6 and 12 hour VCM(+)groups (2.91, 3.55) was significantly reduced compared to the VCM(-) group (6.96) (p<0.05).
Conclusions: :
Early intravitreal injection of VCM was effective in suppressing the development of E. faecalis endophthalmitis.
Keywords: endophthalmitis • antibiotics/antifungals/antiparasitics • cataract