Mitomycin C in sinus surgery: preliminary results in a rabbit model.

Mitomycin C (MMC) is an antineoplastic agent with an antiproliferative effect on fibroblasts. It is routinely used topically in ophthalmology. The goal of this research project is to evaluate if topically applied MMC at the site of a maxillary antrostomy will inhibit the healing process of the mucosa and reduce the risk of postoperative stenosis. Antrostomies were carried out in both maxillary sinuses of 10 rabbits. For each rabbit, MMC is applied at the site of the antrostomy on one side while the other side serves as control. Antrostomies are re-evaluated 3 weeks later and their areas measured precisely. Seven of 10 control antrostomies were closed compared to only 1 of the 10 treated with MMC (p = .014). Comparison of the areas of the control and treated sides also proved to be statistically significant (p = .0039). Topical application of MMC was not associated with any systemic side effects and did not cause any permanent microscopic changes since the mucosa re-epithelialized normally. These results suggest that MMC slows the postoperative healing process of the nasal mucosa of the rabbit without affecting re-epithelialization. This could allow antrostomies to heal with a wider diameter, decreasing the risk of postoperative stenosis. Our next step will be to reproduce these results following functional endoscopic surgery on humans.