Corneal tissue levels of topically applied ofloxacin

To evaluate the levels of ofloxacin (Ocuflox) in human corneal tissue in patients exposed to various dosing regimens and application methods.

Corneal Consultants of Indiana, Indianapolis, Indiana, USA.

Forty patients meeting inclusion criteria were recruited from persons scheduled to have penetrating keratoplasty (PKP). Patients were placed into one of two study groups of 20 each based on dosing regimen and application method. The SAS GLM (General Linear Models) procedure was used to test for differences in mean Ocuflox tissue concentration among study groups and for interaction effects of preoperative diagnosis, trephine size, dosing regimen, and corneal integrity.

Corneal tissue concentrations of Ocuflox were elevated significantly by varying drug application methods and dosing schedules before PKP. Eyes receiving medication every 15 minutes for 4 hours had significantly higher levels of Ocuflox than those receiving the drug in six doses over 24 hours before surgery. Ocuflox concentrations exceeded the MIC90 (minimum inhibitory concentration) for key ocular pathogens in essentially all cornea specimens studied.

Ocuflox penetration was improved by administering it in a controlled setting at 15 minute intervals over 4 hours. The drug provided high tissue levels in both the cornea and aqueous humor, which together with its broad range of antibacterial coverage, should make it a good choice for prophylactic treatment.