Presentation
Left painless neck swelling.
Patient Data





Oval-shaped well-defined cystic lesion is noted at the left side of the neck resting on the left ala of thyroid cartilage (left side of larynx), deep to the left strap muscles. It shows intact smooth uniform non-enhancing thick wall with homogenous fluid density content averaging 15 HU.
Inferiorly it ends just at the upper border of the left thyroid lobe. Superiorly, it ends just at the lower border of the left submandibular gland and hyoid bone. It is anterior to the carotid sheath which remains intact. Anteriorly, stretching left strap muscles and anterior jugular vein.
No relation to the sternomastoid muscle. It peaks to the midline.
Case Discussion
Features are most likely representing uncomplicated left lateral thyroglossal duct cyst. Thyroglossal duct cyst is the most common congenital neck cystic swelling. It is typically located in the midline, however can be lateral, and are the most common midline neck mass in young patients.