Mitomycin C-enhanced revision endoscopic dacryocystorhinostomy: a prospective randomized controlled trial.

OBJECTIVES (1) To conduct an adequately powered randomized controlled trial investigating the safety and efficacy of mitomycin C-enhanced revision endoscopic dacryocystorhinostomy (DCR) and (2) to analyze causes of failure after primary endoscopic DCR. STUDY DESIGN A randomized controlled study. SETTING General hospital. SUBJECTS AND METHODS Seventy-six revision endoscopic DCRs were randomized into 2 groups: endoscopic DCR with mitomycin (group I), where 0.5 mg/mL mitomycin C was applied for 10 minutes, and endoscopic DCR without mitomycin (group II). Follow-up settings were done to document the patient's subjective improvement, to judge ostium patency on irrigation, and to record any complications. RESULTS Causes of failure in the original 92 patients included canalicular obstruction (14%), small misplaced bony window (43%), very small nasolacrimal stoma due to development of synechia (23%), and complete closure of nasolacrimal stoma with tough fibrous tissue (63%). There was no significant difference between the 2 groups in subjective and objective success rates and adverse events. Group I demonstrated a significantly longer operative time and a significantly lower number of debridement sessions (mean of 1.2 vs 1.9). CONCLUSIONS Recurrent nasolacrimal duct obstruction after primary endoscopic DCR is mainly due to reclosure of the nasolacrimal stoma with synechia and fashioning of the small misplaced bony window. Mitomycin C does not increase the success rate of revision endoscopic DCR. It is a safe procedure and may be of value only in patients inaccessible to strict follow-up because it induces a better healing profile in terms of mucosal recovery, wound healing, and less need for debridement sessions.