A 27-year-old man presented with a swelling on the right side of the neck since one year. The swelling gradually increased in size and had been associated with hoarseness of voice since seven to eight months. The patient also complained of difficulty in deglutition associated with tinnitus in the right ear. Local examination revealed a large cystic mass in the upper lateral part of the right side of the neck with mild pulsatality. Mild loss of the right naso-labial fold was noted. There was right sided mixed hearing loss. On indirect laryngoscopy, there was right vocal cord palsy.

RADIOLOGICAL FINDINGS:

A CT SCAN of the base of the skull showed a hypodense lesion (Fig.1) in the region of the carotid fossa. The lesion showed intense enhancement on post contrast images (Fig.2). There was splaying of the ECA and ICA. Another similar lesion was seen in the jugular fossa. On bone windows, there was erosion of the jugular spine (Fig.3).

Fig. 1	Fig. 2
Fig.3

An MRI of the neck showed a hypointense soft tissue mass in the right jugular fossa. On T1W images, this lesion was seen to extend into the posterior fossa below the level of the external auditory canal. Multiple flow voids were seen within it. The lesion remained hypointense on T2W images as well. The lesion was in contiguity with the carotid canal anteriorly. Another soft tissue intensity mass was seen in the region of the common carotid bifurcation - hyper to isointense on T2W images. This mass produced splaying of the ECA and the ICA (Fig.4) and extended into the parapharyngeal space medially and submandibular region anteriorly. Both the lesions showed intense enhancement on post contrast scans (Fig.5&6) - showing a classic salt and pepper appearance on post contrast scans.

Fig.4			Fig.5
Fig.6			Fig. 7

A FOUR VESSEL ANGIOGRAM was performed. This showed spaying of the carotid bifurcation (Fig.9) and an intense blush (hypervascularity) of the tumour (Fig.10). The characteristic position of the tumour gives the clue to the diagnosis.

Fig. 8	Fig.9
Fig.10

FNAC of the lesion was performed. This showed it to be a paraganglioma.

Direct percutaneus glue embolisation of the right carotid body tumour and transarterial sclerotherapy of right glomus tympanicum lesion were performed. There was significant reduction in the vascularity of the lesion. This was shown by the follow up MRI angio (Fig.11) and sonography (Fig.12).

Fig. 11	Fig. 12

FINAL DIAGNOSIS: GLOMUS JUGULARE AND CAROTID BODY TUMOUR (MULTIPLE CHEMODECTOMAS).

DISCUSSION:

Pathophysiology:Glomus tumors of the head and neck paraganglia are part of the extra-adrenal neuroendocrine system. At birth, small patches of paraganglionic cells can be widely dispersed throughout the body, mostly in association with autonomic nervous tissue. In the head and neck, such areas include the chemoreceptive areas (glomus tissue) of the carotid bifurcations, the aortic arch, and the temporal bone. The major paraganglia that do not undergo involution are the carotid bodies. They line the medial wall of the bifurcation of the common carotid artery. These paraganglia are functionally important chemoreceptive organ for homeostasis. Specifically, they detect changes in arterial partial pressures of oxygen and carbon dioxide and changes in pH and other blood-borne factors.

Clinical presentation:Carotid body tumors have no sex predilection. However, studies have shown evidence of a sex predilection with jugulare tumors, with a female-to-male ratios of 5:1. Studies indicate that the incidence of carotid body tumors peaks in patients aged 45-50 years, whereas the incidence of tumors of vagal and jugular origin peaks in those aged 50-60 years. Glomus tumors of the head and neck are extremely rare in pediatric patients. Patients with carotid body tumors are largely asymptomatic and have a mobile, nontender, slow growing, lateral neck mass. Some patients may report hoarseness and dysphagia associated with compression of the trachea and esophagus and/or vertigo and paresis resulting from cranial nerve compression. Patients with functioning tumors may present with hypertension, headaches, palpitations and tachycardia resulting from increased levels of circulating catecholamines.

Imaging studies: Contrast-enhanced CT demonstrates enhancing soft-tissue masses at characteristic locations - which is a key to the diagnosis. Nonenhanced CT imaging can demonstrate glomus tumors, but the demonstration of a strongly enhancing mass is typical. CT demonstrates carotid body tumors at the level of the carotid bifurcation, respectively splaying the internal and external carotid arteries medially and laterally. These tumors can vary in size, but their location within the bifurcation is critical for diagnosis. Similar to CT imaging, contrast-enhanced MRI demonstrates enhancing soft-tissue masses at characteristic locations. Demonstration of a strongly enhancing mass is typical in the diagnosis of a glomus tumor. As with most soft tissue tumors, glomus tumors are isointense on T1W MRI and hyperintense on T2W MRI. Contrast-enhanced imaging can show intense tumor enhancement. MRI can show densely enhancing carotid body tumors at the level of the carotid bifurcation, which respectively splay the internal and external carotid arteries medially and laterally. Sonography can demonstrate the extent of the masses and show their locations. Because of tumor neovascularity, Doppler USG sampling of cervical masses, such as carotid body tumors, can be helpful in diagnosis. Glomus tumors of the head and neck are typically highly vascular, as shown on angiograms. This finding differentiates them from other types of neck neoplasia.

Treatment:The preferred method of treatment for glomus tumors of the head and neck is surgery. However, because most paragangliomas are slow-growing and benign, radiation treatment alone or no treatment at all is preferred in elderly patients in whom the risks of surgery are relatively high and the tumor is unlikely to cause serious morbidity or mortality. If the patient is young, surgery is the best available option because it is the only option that allows total cure. Embolization is a common technique used as the lone treatment option or as a precursor to surgical excision. As a result of the highly vascular nature of these neoplasms, embolization is an effective technique that is aimed at starving the lesion of its blood supply and inducing necrosis.