PROLONGED LOCALIZED TISSUE EFFECTS FROM 5-MINUTE EXPOSURES TO FLUOROURACIL AND MITOMYCIN-C

Rabbits undergoing full-thickness glaucoma filtering surgery were exposed for 5 minutes to one of three intraoperative treatments: (1) distilled water; (2) fluorouracil, 50 mg/mL; or (3) mitomycin C, 0.4 mg/mL. Tissue samples were taken from the subconjunctival and scleral tissues at the treated area and 90-degrees and 180-degrees from the center of the treated area and the adjacent cornea 2 mm from the limbus, 1 hour, 5 days, and 30 days postoperatively. The biopsy specimens were then placed in tissue culture media and the fibroblast outgrowths measured. Five-minute intraoperative treatments with fluorouracil resulted in a reversible delay of fibroblast outgrowths from treated sub-conjunctival and scleral tissues of just over 1 week in this model, whereas treatment with mitomycin C, 0.4 mg/mL, resulted in prolonged inhibition of at least 30 days. These effects were localized to the area treated. The many clinical implications of these findings are discussed.