Association of cholesterol granuloma and aspergillosis in the sphenoid sinus.

Cholesterol granuloma (CG) is usually associated with chronic middle ear disease, and is not common in the paranasal sinuses. Additionally, it is very rare for cases of CG to be associated with a fungal infection. However, in this paper, we report a case of sphenoid sinus CG that is associated with aspergilloma in a 78-year-old male patient who presented with right hemifacial pain, headache and toothache. CT revealed the presence of an expansile cystic mass lesion in the sphenoid sinus that showed a high signal intensity on both the T1 and T2 weighted images. This mass was later determined to be CG. The suspected etiologic mechanisms of both CG and aspergilloma of the paranasal sinuses are similar, and impaired drainage and obstruction of the ventilation of the paranasal sinuses are considered to be the causative mechanism of both diseases. Overall, the results of this study indicate that the use of MRI findings could be helpful for differentiating CG from other paranasal sinus mass lesions.