A mucocele is a cystlike, mucus-containing sac that can form within a paranasal sinus. A pyocele is a mucocele that contains purulent material as a result of superinfection.
Pathogenesis: A mucocele may be caused by adhesions (postinflammatory, post-traumatic, or postoperative) that obstruct drainage from the paranasal sinus system. Mass lesions (polyps, tumors) can also obstruct the drainage tracts, leading to mucocele formation. The outflow obstruction causes the mucocele to exert increasing pressure on the surrounding sinus walls, resulting in progressive thinning of the bone. In this way the mass can erode into adjacent structures such as the orbit or even the cranial cavity. The most common site of occurrence is the frontal sinus, followed by the ethmoid cells, maxillary sinus, and sphenoid sinus.
• an isolated, tense swelling over the anterior wall of the frontal sinus is a symptom for frontal sinus mucocele.
• swelling in the cheek area with upward displacement of the orbital contents is more
characteristic of a maxillary sinus mucocele.
• Unlike other sinus mucoceles, sphenoid sinus mucoceles often have nonspecific clinical manifestations, with compliants (headache radiating to the vertex and occiput)
Treatment: The treatment of choice is surgical removal of the mucocele.