Visual loss: a rare complication of maxillary sinus mucocele.

Mucoceles are cystic formations lined with respiratory epithelium that contain a mucoid or mucopurulent fluid. Although benign, mucoceles are locally expansive, due to continuous production and accumulation of mucus, resulting in erosion and underlying bone remodeling. This may affect the orbit, skull base, or soft tissue of the face. Frontal, ethmoidal, and fronto-ethmoidal sinuses are the most common locations, while the, maxillary and sphenoidal sinuses are less frequently affected. Maxillary sinus mucoceles are rare, accounting for less than 10% of all mucoceles in the USA and Europe.1 Orbital symptoms are relatively common in patients with mucocele, due to the expansion of the lesion into the orbit.1 These symptoms are usually caused by ethmoidal, sphenoidal, and frontal mucoceles. Ophthalmologic impact is unusual from maxillary mucoceles. As to orbital symptoms,