Purpose: To assess the efficacy of intraoperative mitomycin C (MMC) during silicone intubation (SI) as a substitute for dacryocystorhinostomy (DCR) in nasolacrimal duct (NLD) obstruction.

Methods: In a prospective, randomized, double-blind study, 88 candidates of DCR for NLD obstruction were randomly assigned into two groups of SI with application of either MMC (0.2 mg/ml for 2 minutes) or placebo.

Results: After a mean follow-up interval of 8 months, 25 of the 43 eyes in the MMC group and 21 of the 44 eyes in the placebo group had a successful outcome and were free of tearing and discharge (P=0.331). In patients with simple epiphora and less than 6 months of duration of symptoms, SI alone was effective in 83% of patients; MMC application during SI did not show additional benefit over SI alone in this group of patients. But in patients with simple epiphora and more than 6 months duration, the application of MMC during SI resulted in better efficacy compared to SI alone. The overall success rates in the patients with chronic dacryocystitis was lower (23%) compared to patients with epiphora only (63.7%).

Conclusion: SI alone could effectively substitute for a more extensive procedure such as DCR in patients with simple epiphora particularly in whom their symptoms has been newly developed. In cases with longer duration of symptoms of epiphora, application of MMC would increase the success rate significantly.