ABSTRACT
The complications of sinusitis are usually related to infection escaping from within the paranasal sinuses and invading the adjacent anatomical structures. A mucocele is the most common expansile lesion seen in the paranasal sinuses. The sinuses involved in decreasing order of frequency are the frontal, the ethmoid, the maxillary, and the sphenoid sinuses. The magnetic resonance imaging signal intensity of mucoceles varies according to the amount of hydrogen protons and glycoprotein complexes present within the mucocele. Mucoceles of the ethmoid sinus tend to cause proptosis and lateral displacement of the globe. The polypoidal mucocele is a separate entity in which patients present with diplopia and proptosis. A significant number of maxillary sinus mucoceles follow surgical procedures of the maxillary sinus, and these are characteristically found to be laterally placed in the sinus as opposed to filling the entire antrum. Sphenoid sinus mucoceles tend to present with headaches or with retro-orbital or periorbital pain.
