Cholesterol granuloma of the frontal sinus.

It is common to see cholesterol granuloma in the mastoid air cells, less common in the orbit, and uncommon in the paranasal sinuses. Cholesterol granuloma is thought to be due to an interruption to normal aeration with impaired lymphatic drainage, resulting in a closed cavity where it may form. These expanding cysts cause bone destruction and compression of the surrounding structures that lead to clinical symptoms. Diagnosis and management of cholesterol granuloma cysts can be challenging. Magnetic resonance imaging (MRI) and computed tomographic (CT) scans are usually diagnostic. We present a rare case of cholesterol granuloma in the frontal sinus, few cases have been reported in the literature.