Abstract
Purpose: :
To compare the antibacterial effect of moxifloxacin administered as a single intrastromal corneal injection to topically administered moxifloxacin in the treatment of Pseudomonas aeruginosa (PA) keratitis in a rabbit model.
Methods: :
Each eye of 24 New Zealand White rabbits was intrastromally inoculated with ~106 colony-forming units of PA. 16 hours later, 6 rabbits were euthanized to determine the number of corneal bacterial colonies at the onset of therapy. The remaining 18 rabbits were divided equally into 3 groups: 1) intrastromal moxifloxacin, 2) topical moxifloxacin, and 3) topical saline control. For group 1, a single intrastromal dose of 0.05 cc moxifloxacin was injected around the infiltrate of each cornea. For groups 2 and 3, one drop was applied every 15 minutes for 5 doses then every 30 minutes for 14 doses per eye. 9 hours after the initiation of treatments, all animals were euthanized and corneas were harvested. Colony counts from all corneas were determined.
Results: :
After the treatment period, the intrastromal and topical moxifloxacin groups had significantly lower colony counts than saline control (P<0.05, ANOVA). There was no significant difference between the colony counts of the intrastromal and topical moxifloxacin groups.
Conclusions: :
Intrastromal and topical moxifloxacin showed equivalent efficacy against P. aeruginosa in a rabbit keratitis model. Intrastromal antibiotic injection may be an efficacious alternative to around-the-clock drops in treating bacterial keratitis.
Keywords: cornea: basic science • antibiotics/antifungals/antiparasitics • keratitis