Human vitreous penetration of imipenem

The purpose of this study was to determine imipenem concentrations in vitreous humor of non-infected human eyes. Ten patients undergoing vitrectomy were infused with a single dose of either 0.5g (5 patients) or 1g (5 patients) of imipenem. Vitreous humor was withdrawn 2 or 4 hours after the end of the infusion. Results differed in relation to the dose. After 0.5g, vitreous levels were stable (approximately 0.20 mg/l), but after 1g they were significantly higher (approximately 2 mg/l). These levels were above the minimum inhibitory concentration of imipenem for 90% (MIC 90) of the main species responsible for endophthalmitis.