OFLOXACIN PENETRATION INTO THE EYE AFTER INTRAVENOUS AND TOPICAL ADMINISTRATION

Purpose: To determine the aqueous and vitreous fluid penetration of of loxacin after a combined topical and single intravenous dose protocol before vitrectomy surgery. Materials and Methods: Before undergoing vi trectomy surgery, patients were given two drops of ofloxacin 0.3% topi cally and a single intravenous dose of ofloxacin 400 mg. Aqueous (mean , 43 minutes) and vitreous (mean, 53 minutes) fluid samples were colle cted at the start of the surgical procedure. The samples were analyzed for ofloxacin penetration. Results: The mean aqueous fluid concentrat ion was 1.083 mu g/mL +/- 0.406. The mean +/- SD vitreous fluid concen tration in nondiabetic patients with intact vitreous was 0.352 mu g/mL +/- 0.301. Vitreous levels obtained more than 50 minutes after admini stration (0.414 mu g/mL +/- 0.336) were generally higher than those ob tained after less than 50 minutes (P = 0.12). Eyes with prior vitrecto mies achieved better ofloxacin penetration (0.984 mu g/mL +/- 0.680) t han did nonvitrectomized eyes. Conclusion: Ofloxacin achieved measurab le aqueous fluid penetration after topical and intravenous administrat ion, Aqueous levels were above the minimum inhibitory concentration fo r most ocular pathogens. Vitreous levels were adequate in vitrectomize d eyes to achieve inhibitory concentrations against many common ocular pathogens. Combined preoperative topical and a single dose of intrave nous ofloxacin may provide inhibitory aqueous and vitreous antibiotic levels in vitrectomized eyes in cases where intravitreal antibiotics a re not considered and oral administration is not practical.