Diagnosis

Glomus Jugulare tumor (a.k.a. chemodectoma or nonchromaffin paraganglioma).

Findings

CECT demonstrates a destructive, enhancing mass centered in the right jugular foramen.

Coronal T1W post contrast MRI confirms these findings and demonstrates a characteristic "salt and pepper" appearance to the mass.

Right external carotid artery angiogram shows a large, hypervascular tumor fed by the right occipital, ascending pharyngeal, and posterior auricular arteries with evidence of arteriovenous shunting.

Discussion

This patient was status post embolization and resection of a previous right glomus jugalare tumor one year prior this presentation and returned to clinical attention due to recurrent hearing loss and tinnitus, a common presentation of these tumors. Other presenting symptoms include hearing loss, nerve palsies, arrythmias, and flunctuating blood pressure.

Glomus Jugulare tumors arise from paraganglionic cells associated with the vagus nerve in the jugular bulb, are slow growing, and can erode bone, as in this case. Vascular encasement of invasion can also be seen. The tumor tends to spread by the "path of least resistance"-inferiorly along the post-styloid parapharyngeal space and superiorly into the posterior cranial fossa-and roughly 10% are multiple at presentation. Angiography is the standard of case, to evaluate blood supply to the tumor and in some cases to offer preoperative embolization.

The differential for a hypervascular erosive jugular foramen mass also includes: meningioma, hemangiopericytoma, metastasis (such as from kidney or thyroid), angiofibroma, granular cell tumor, endolymphatic sac tumor, and plasmacytoma. While nasopharyngeal masses and schwannomas may grow into the jugular foramen, these are not typically hypervascular.

Radiology Clinics of North America, September 2000, 1059-76 Case Review: Head and Neck Imaging. Yousem.