Mucocele Formation after Surgical Treatment of Inverted Papilloma of the Frontal Sinus Drainage Pathway

Abstract

Background Inverted papillomas (IP) inserted in the frontal sinus and/or recess may be treated by using an endoscopic endonasal or an external approach. There are still few data available on this uncommon localization of IPs. Objective To report our experience in the management of IP of the frontal drainage pathway, to describe a previously unreported specific complication of this surgery, and to discuss the optimal surgical strategy. Methods A retrospective study of the patients at a tertiary care center between 2004 and 2014 who were operated on for an IP with an insertion in the frontal recess and/or the frontal sinus. Clinical charts were reviewed for demographics, clinical presentation, imaging findings, surgical treatment, and outcome. Results Twenty-seven patients were included. Patients were operated on by using a purely endoscopic approach (Draf procedure; n = 14 [51.9%]) when the IP was inserted in the frontal recess and/or the frontal sinus infundibulum (with a nasoseptal-septoturbinal flap placed on the exposed bone in four patients), or by using a combined endoscopic and open approach (osteoplastic flap procedure; n = 13 [48.1%]) when the IP invaded the frontal sinus beyond the infundibulum. There were two recurrences (7.4%), with a mean follow-up of 40 months (range, 9-123 months). During follow-up, single or multiple iatrogenic frontal mucoceles were observed in 10 patients (37%), with a mean delay of 60 months (range, 27-89 months). These mucoceles occurred both after using endoscopic (n = 3) or combined (n = 7) approaches, and required a surgical treatment in eight patients. No postoperative mucocele was observed in the four patients who had had a septal flap. Conclusion In our experience, an approach based on the localization of the IP insertion provided acceptable results in terms of the local control rate (92.6%). However, the significant rate of postoperative mucoceles indicated that specific strategies (such as local flaps) still need to be developed to avoid this iatrogenic complication.