Glomus jugulare tumors are highly vascular, benign (non-cancerous) tumors that arise along the dome of the jugular bulb. Centered within the jugular foramen, directly below the middle ear, tumor cells may eventually grow into the middle ear, along neural foramina, enter the posterior cranial fossa or invade either air cells or the marrow spaces of the lateral skull base. Pulsatile tinnitus, the most common symptom of glomus tumors, occurs due to the vascular nature of these tumors. Conductive hearing loss can also occur as the tumor grows into the middle ear space and prevents transmission of sound through the eardrum and ossicular (hearing bone) chain. Very large glomus jugulare tumors may cause vertigo (feeling that the world is spinning when you are not moving), facial paralysis or weakness, difficulty swallowing, hoarseness and sensorineural hearing loss.
Glomus jugulare tumors are first detected/evaluated in the office by a thorough microscope (binocular) evaluation of the ear and comprehensive cranial nerve examination. Due to the highly vascular nature of the tumor, a reddish mass is typically observed behind the eardrum. Imaging studies, including high-resolution temporal bone CT scans, MRI scans of the brain with internal auditory canal protocols and MR angiography (to get more information about the vascular properties of the tumor), are indicated. Three treatment options exist for glomus jugulare tumors and recommendations are based on the individual properties of each tumor. Because these tumors are slow growing, observation using serial imaging is an option if the tumor is small and not causing intra-temporal or neurologic symptoms. Due to the glomus jugulare tumor being located next to the jugular vein and several important nerves, a team of surgeons is often involved if surgical removal is recommended, including a neurotologist, neurosurgeon and head and neck surgeon. Lastly, conformal radiation is an option that may halt the growth of the tumor by cutting off its blood supply, but the tumor is not removed. Those undergoing surgery may require a formal cerebral angiogram with embolization of tumor vessels 24 – 48 hours prior to resection.