Paranasal sinus fungus ball is within the non-invasive forms and is characterized by the presence of aggregated hyphae that do not invade the sinus mucosa. Mucoceles are benign, expansile, cyst-like lesions of the paranasal sinuses. The mucoid secretions of mucoceles are usually sterile. However, secondary infections, mostly bacterial, may lead to the development of pyocoeles. Although an association between a fungus ball and a mucocele is rare in the paranasal sinuses, this disease entity should be considered in the differential diagnosis of expansile, cystic sinus lesions.
In this article, clinical and radiological findings of a 61-year-old male patient with isolated sphenoid sinus fungus ball within a mucocele presented with headache and periorbital pain were discussed with recent literature.