Recurrent Cholesterol Granuloma Secondary to Delayed Extrusion of Endovascular Coil of a Pseudoaneurysm

A 58-year-old woman with a history of left revision canal wall-up mastoidectomy for chronic otitis media 10 years prior presented with bloody drainage from her old postauricular incision. At the time of her revision surgery, the patient was found to have a 2-cm pseudoaneurysm of the petrous portion of the carotid artery that was filling the middle ear space and required internal carotid artery occlusion by interventional radiology. The patient was taken back to the operating room after successful internal carotid artery embolization and underwent ear canal oversew for definitive treatment of her chronic otitis media. The patient had done well in follow-up and presented 10 years later with complaints of dark liquid drainage and a postauricular mass. On physical exam, she had an intact oversewn ear canal and a 2.5 by 3 cm hard lesion in the skin of the postauricular crease with drainage from the inferior aspect. Imaging on CT scan demonstrated a soft tissue mass filling the entire mastoid cavity. Four-vessel cerebral angiogram did not show any feeding vessels nor did it demonstrate connection with the coiled carotid artery. The patient was taken to the operating room and underwent a left transtemporal approach for resection the mass. In the operating room, she was found to have a large cholesterol granuloma and extrusion of the intravascular coil. The cholesterol granuloma was removed and fat graft harvested and placed over the extruded intravascular coil. It is believed that the extruded coil was the cause of a foreign body reaction leading to cholesterol granuloma formation.