Surgical Treatment for Paranasal Mucoceles: Usefulness of Preoperative MRI and Computer-Aided Surgery

Abstract

Objectives:

Surgical procedures for paranasal mucoceles are associated with different levels of difficulty depending on the sites and the number of mucoceles, because the walls of mucoceles are excised and opened into the nasal cavity. We examined the usefulness of magnetic resonance imaging (MRI) in addition to computed tomography (CT) and also that of computer-aided surgery.

Methods:

The study involved 70 patients undergoing surgical treatment for paranasal mucoceles. Preoperative CT and MRI were carried out, and mucoceles were opened into the nasal cavity by endoscopic sinus surgery (ESS) using computer-aided surgery. Mucosal flaps were created within the nasal cavity and inserted into the mucoceles by sliding them down.

Results:

CT confirmed bone defect sites, and tumor differentiation was performed using MRI preoperatively. Multilocular mucoceles could be confirmed intraoperatively in 19 patients and on preoperative MRI in 18 cases (94.7%). Preoperative nasolacrimal ducts and orbital cavities were marked on the monitor by computer-aided surgery so that they could be avoided while the walls of mucoceles were excised and widely opened into the nasal cavity. There were no postoperative complications or residual mucocele, and only one patient (1.4%) showed re-closure of the opened site 6 months after the operation.

Conclusions:

Evaluation of the mucoceles by preoperative MRI was useful to accurately grasp the number of mucoceles and their sites. Because concomitant use of computer-aided surgery allows the mucoceles to be opened as safely and widely, it can be considered to be useful for reducing the rate of postoperative re-closure.