A T1-weighted, fat-suppressed, contrast-enhanced image showed an enhancing lesion in apparent continuity with the adjacent retromandibular vein (Figure 2).
Incidentally noted on axial, postcontrast,T2-weighted images and sagittal T2-weighted images was moderate, diffuse enlargement of the retromandibular vein (Figure 3).
1-3) By comparison, a venous ectasia developing within the parotid portion of the retromandibular vein is rare, with fewer than 10 cases reported in the literature.
This information, combined with the further imaging demonstration of continuity of each mass with the retromandibular vein (also known as the posterior facial vein), confirmed the diagnosis of venous ectasia.
5) The etiology of retromandibular vein aneurysms are likely similar to those of other venous neck aneurysms and case reports suggest that venous aneurysms of the parotid gland tend to appear suddenly.
The mild diffuse dilatation of the retromandibular vein in Case 3 does not mimic a parotid mass on imaging and is shown to demonstrate the differing imaging appearance relative to the two ectasia cases.