RESUMEN
Maxillary sinus mucoceles account for less than 10% of all paranasal sinus mucoceles. They are reported mostly as long-term sequelae of Caldwell-Luc operations. Orbital involvement is an extremely rare condition that might result in orbital complications. A 43-year-old woman presented to the ophthalmology department with progressive ophthalmologic complaints. She was referred to our department for suspicion of a mass in the left maxillary sinus. The patient had undergone a left Caldwell-Luc sinus procedure two years before followed by two maxillary sinus lavages. Findings of computed tomography and magnetic resonance imaging of the paranasal sinuses were suggestive of a maxillary mucocele. Endoscopic sinus surgery and Caldwell-Luc procedure were performed to remove the mucocele that filled the maxillary sinus. Because the eyeball prolapsed through the defect in the inferior orbital wall to the maxillary antrum, a Silastic sheath was placed between the orbital base and the eyeball. No postoperative complication was observed.