Thyroglossal cysts are benign cysts that form in the midline of the neck.
They can form anywhere along the remnant fo the Thyroglossal Duct, which gets from eh base of the tongue, to the sternal notch.
Many individuals shave a remnant of the Thyroglossal duct that persists at birth. The natural physiology is that the duct atrophies during development, but in some individuals this process does not occur.
For reasons that are not fully understood, some of those with a persistent duct will, later in life, go on to form a cyst within the duct.
The cysts are smooth, regular, painless, non-tender, fluctuant masses. They occur in the midline in the neck, and move on movements of the tongue. This helps them to be distinguished from other lumps in the neck which are not connected to the tongue, and thus do not move when the tongue is moved.
It is a very common exam question to have a lump in the neck that moves with swallowing!
- Thyroid masses – e.g. goitre, nodule
- Inflamed lymph node – e.g. lymphoma