Thyroglossal Duct Cyst

This sagittal reformat of a multidetector-row CT of the neck shows a thyroglossal duct cyst - click image for arrows.
TGDC are the most common congenital neck cyst, three times as common as branchial cleft cysts and are usually asymptomatic until they become secondarily infected. Typically they present during childhood (90% before the age of 10). Unless infected, they are painless, fluctuant masses which spread the strap muscles.
TGDC are lined by respiratory or squamous epithelium, frequently with small deposits of thyroid tissue with colloid. Malignancies do occur in less than 1% of TGDC, and are most commonly papillary thyroid carcinoma (85%).
Read more about, and see more images, of this case at Radiopaedia.org (click here)
Reference: StatDx.com
Credit: Dr Frank Gaillard
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