The ability of mitomycin C to inhibit fibroblasts in vitro has prompted its use during standard surgical procedures as a means of preventing the development of adhesions and stenosis. We conducted a prospective study to evaluate the effectiveness of topical mitomycin C in maintaining an open external auditory canal in 6 ears of 4 patients with aural fibrotic atresia who were undergoing meatoplasty. During the procedure, we applied 1 ml of mitomycin C (0.4 mg/ml) for 4 minutes to the external auditory canal (in 1 case, mitomycin C was reapplied to an ear 1 month later). Between 3 and 14 months postoperatively, the patency of the ear canal was assessed visually and hearing was evaluated audiometrically. Adequate patency was achieved in 5 of the 6 ears (83.3%), and the air-bone gap in these 5 ears had improved to 10 dB or less. No postoperative complications or sensorineural hearing loss was observed. In this very limited number of cases, we found that the intraoperative use of mitomycin C appeared to have been helpful in preventing scarring in both congenital and secondary fibrotic atresias of the external auditory canal. These preliminary results are encouraging, and a prospective, placebo-controlled study appears to be warranted.