advertisement
Abstract #8728 Published in IGR 5-1
Toxic effects of subconjunctival 5-fluorouracil and mitomycin C on ciliary body of rats
Levy J; Tessler Z; Rosenthal G; Klemperer I; Zirkin HJ; Kachko L; Lifshitz TInternational Ophthalmology 2001; 24: 199-203
PURPOSE: The effects of the subconjunctival injection of mitomycin C (MMC) and different concentrations of 5-flourouracil (5-FU) on the epithelium of the ciliary body of 20 Sprague Dawley (SD) rats were studied. METHODS: Twenty rats were divided into four treatment groups. The first three groups received 0.2 ml of 5, 10, and 30 mg of 5-FU subconjunctivally, respectively, and the fourth group, 0.2 ml of 0.4 mg/ml MMC subconjunctivally. The right eye received 0.2 ml of the antimetabolite, while the left eye was injected with 0.2 ml of saline subconjunctivally, as a control. The eyes were examined histologically in a masked fasion, by light and transmission electron microscopy. In each treatment group, two eyes were examined after one week, and three eyes one month after the subconjunctival injection. RESULTS: Electron microscopy revelaed toxic effects in the epithelium of the ciliary bodies of all treatment groups. The 5-FU group revealed focal mitochondrial edema, enlargment of the intercellular spaces, and dilatation of the intracellular spaces. The MMC group showed pyknotic nuclei, enlargment of the intercellular spaces, and irregular flattened epithelial cells. The severty of the changes correlated with the concentration and length of exposure. No pathology was found by light microscopy in any of the groups. CONCLUSIONS: This study demonstrated that the subconjunctival antimetabolites MMC and 5-FU can penetrate the sclera and exert toxic effects on the epithelium of the ciliary body, even in low doses. These changes were only apparent on electron microscopy, and were still present one month after the injection. These findings may contribute to the theory that the application of antimetabolites during or after surgery has a direct effect on the epithelium of the ciliary body, as well as its known effect on the conjunctiva. Further studies are needed to evaluate its effect on intraocular pressure.
Dr. J. Levy, Department of Ophthalmology, Soroka Medical Center, Ben-Gurion University, Beer Sheva, Israel
Classification:
12.8.10 Woundhealing antifibrosis (Part of: 12 Surgical treatment > 12.8 Filtering surgery)
