Mucoceles are expansive pseudocystic formations with mucous retention that originate in one or more paranasal sinuses. The growth is very slowly but ands up compressing and displacing adjacent structures such as the orbit (Figure 1) (Figure 2).
Fronto-ethmoidal mucoceles are the most frequent (80%) displacing eventually the orbit.
Maxillary (17%) and sphenoidal (3%) mucoceles are less common.
Expansion and neighborhood involvement should be evaluated by means of CT scans. Sometimes the collaboration of neurosurgeons and ophthalmologists is required.