Other than the history and physical exam, which of the following tests is considered an essential feature of the preoperative evaluation of a patient with a suspected thyroglossal duct cyst?

e. None of the above

A thyroglossal duct cyst is typically a midline structure connected to the foramen cecum at the base of the tongue, that is pulled proximal and superior as the tongue protrudes. It may be superior or inferior to the hyoid and is occasionally slightly off the midline. Because the thyroglossal cyst may rarely contain the patient’s only thyroid tissue, some have recommended a technetium-99m radioisotope thyroid scan before excision. However, excision of the cyst is indicated regardless, because infection of the cyst is likely, and the dysgenetic thyroid tissue in the cyst has malignant potential. For these reasons, patients with suspected thyroglossal duct cysts require routine surgical excision. Preoperative ultrasound, thyroid scan, T3 and T4 levels, or needle aspiration is not necessary. For those patients who have thyroid tissue in their cysts by pathologic examination, postoperative thyroid function tests identify those who have no remaining thyroid tissue and replacement therapy can be prescribed.