A left sided neck mass.

Carotid body tumours are slow-growing hypervascular lesions arising from nonchromaffin cells within the neural crest in the region of the carotid bifurcation.' They are also referred to as paragangliomas and it is well documented that they may be multiple.2 These lesions have characteristic magnetic resonance imaging (MRI) features that permit accurate diagnosis and precise definition of tumour extent. This report serves to illustrate the radiological appearances in such a case. Case Report A 72 year old man presented with a 6 month history of a painless lump in the left side of his neck. There was no associated dysphagia, hoarseness, otalgia or weight loss. He was a non-smoker. Examination revealed a 3 x 4 cm mobile mass in the anterior triangle of the neck on the left side, just below the angle of the mandible. Otological and neurological examination was normal. Fig 1. Axial T1I-weighted (TR600/TE11I) image through the neck (at the level of the carotid bifurcation). The clinical impression was of an occult primary tumour with metastases in the neck. The patient was booked for excision biopsy of the mass. At operation the tumour was found to be adherent to the carotid artery. On the basis of this finding the lesion was left intact, the wound closed, and the patient referred for MRI of his neck. Axial Ti-weighted images, both before and after Fig 2 Axa Ti wegtdiaeattesm ee Fig 2. Axial TC-weighted image at the same level following intravenous gadolinium-DTPA.