Thyroglossal Duct Cysts
You're bathing your toddler one day when you notice a strange lump at the base of your baby's throat that you've never seen before. Some children are born with a thyroglossal duct cyst, a developmental abnormality that occurs during the formation of the thyroid gland in the first trimester of pregnancy.
When the thyroid tissue descends from the base of the tongue toward the base of the throat, it passes through a duct. Normally, this duct disintegrates on its own and disappears. But in some children, remnants of the duct remain, causing cysts that appear as a lump in the front of the neck. The duct is rarely apparent in babies, whose excess fat conceals the duct. But once the child is older and slims down, a duct cyst becomes more obvious. In some cases, a thyroglossal duct cyst isn't discovered until much later.
If you discover a lump in the throat of your toddler, it's critical to have it evaluated by a doctor. A thyroglossal duct cyst needs to be distinguished from a nodule. To do that, your doctor may ask your child to swallow some water and to stick out his tongue. Both actions will cause the cyst to move upward since it is still connected to the tongue. Your doctor may do blood tests and a thyroid scan to measure thyroid function. He may also do an ultrasound to examine the duct cyst.
Treatment usually involves surgery. If the thyroglossal duct cyst is infected, your child will need antibiotics first to eliminate the infection. The cyst may also need to be drained.
The most common procedure is called the Sistrunk operation, which has been shown to decrease the recurrence of cysts. An incision is made in the center of the neck near the lump in a natural crease, and the entire cyst is removed as well as the cyst tract and a small part of the hyoid bone, which supports the tongue. The procedure is done under general anesthesia. The surgical site is then sutured to minimize visible scarring.
The biggest problem with a thyroglossal duct cyst is the risk for infection. Bacteria from the mouth (which is prevalent) can invade the cyst, causing redness and tenderness. An infected cyst should not be operated on.
After removal, the cyst will be closely examined for thyroid tissue, which can raise the risk for cancer. It's extremely rare, however, to have cancer of the cyst.