LAUSR

Introduction . Mitomycin-C is an alkylating antibiotic used to prevent excessive scar formation in the dacryostoma area after dacryocystorhinostomy. In vitro studies proved its inhibition effect on fibroblast growth in 0.2 mg/ml concentration. Up to date, clinical data on its efficacy remain contradictory. Aim . To evaluate the concentration of Mitomycin-C in nasal cavity and lacrimal sac mucosa after topical application and to determine the clinical efficacy of this procedure. Materials and methods. 30 patients with nasolacrimal duct obliteration underwent an endonasal endoscopic dacryocystorhinostomy. At the end of the surgery, at the osteotomy site, a sponge soaked in Mitomycin-C 0,2 mg/ml was applied for 3 minutes. Nasal mucosa biopsy was performed immediately after application, in 30 minutes, and at the 1st day after surgery. Biopsy material analysis of was performed by liquid chromatography – mass spectrometry. The surgical treatment efficacy was established according to proposed efficacy criteria. Results . The analysis of Mitomicyn-C concentrations established them to be: 626 ± 176 ng/g tissue immediately after application, 230 ± 61 ng/g tissue in 30 minutes after application. In 24 hours after surgery, there was no Mitomycin-C in the tissue. Surgical efficacy was 86.7%, recurrences were found in 13.3% of cases. Conclusion . Surgery clinical results coincide with those obtained by other researchers. But chemical investigation showed that Mitomycin-C tissue concentration was lower than that in previous in vitro studies.