Fig. 4

Axial (a) and sagittal (b) contrast-enhanced CT of the neck demonstrates a well-defined, avidly enhancing soft tissue mass (white arrowheads) within the left carotid space. The mass splays the proximal external and internal carotid arteries (white arrows) at the level of the carotid bifurcation, characteristic of a carotid body tumor (as opposed to a glomus vagale, which typically displaces the ICA and ECA together). The mass encases less than 50% of the left ICA. Note the normal relation of the right ECA and ICA on the contralateral side of the neck (black arrows)