Thyroglossal Duct Cyst

  • Etiology: remnant of thyroglossal duct between base of tongue + thyroid bed, occur along path of thyroid descent from foramen cecum at tongue base to lower neck
  • Imaging: paramedian cyst, closely related to strap muscles (sternohyoid, sternothyroid, thyrohyoid, omohyoid muscles)
  • US: moves with tongue protrusion + swallowing
  • CT: low density, no contrast enhancement unless infected
  • MRI: T1 hypointense, T2 hyperintense, no contrast enhancement unless infected
  • Clinical: 25% suprahyoid, 50% hyoid, 25% infrahyoid

Cases of Thyroglossal Duct Cyst

US of thyroglossal duct cyst
Transverse (above) and sagittal (below) US of the neck shows a cyst in the midline of the neck that moved in relationship with tongue protrusion.