Base of tongue cyst seen on outside MRI. Evaluate for possible vallecular cyst or thyroglossal duct cyst. There is a lobulated structure measuring approximately 18 x 10 mm (CC x TR) at the base of the tongue extending to the anterior margin of the hyoid bone with prominent T2 hyperintense and slight T1 hyperintense signal. It is slightly eccentric to the left of midline. There is no associated fat signal. There is no evidence of abnormal enhancement or significant cervical lymphadenopathy. The thyroid and major salivary glands are unremarkable. The osseous structures are unremarkable. The airways are patent. The imaged intracranial structures are unremarkable.
18 mm lobulated structure extending from the base of the tongue towards the anterior margin of the hyoid bone, favoring a thyroglossal duct cyst based on location. However, other considerations such as lymphatic malformation remain within the differential. 