Female, 35 years old, 21 weeks gestational age, with abnormal prenatal ultrasound, neck teratoma suspected. A multiloculated, T2 hyperintense, predominantly cystic-appearing lesion is evident centered on the right parotid and masticator spaces. This lesion measures up to 27 x 23 x 18 mm. The lesion extends up to the floor of the middle cranial fossa but does not invade the intracranial space. There may, however, be some invasion of the temporal bone structures. Inferiorly, the lesion extends into the submandibular space. Medially, the lesion does appear to enter and encroach upon the nasopharynx. It is difficult to determine how much of the nasopharynx may be occupied by the lesion. The trachea is visualized and does not appear to be directly compressed or invaded by the lesion.
A multiloculated, predominantly cystic appearing lesion is evident with the largest component centered on the right parotid and masticator spaces. Smaller lesion components are seen within the submandibular space, and it does appear that the lesion encroaches to some degree on the nasopharynx. It does not appear that the trachea is directly compressed by this lesion, but some degree of obstruction at the level of the pharynx cannot be excluded.Given the predominantly cystic appearance of this lesion, and its trans-spatial distribution, the differential diagnosis would include a lymphatic or veno-lymphatic malformation. Teratoma would also be reasonable consideration, though these typically show more discrete areas of solid tissue.