Distinguishing between isthmic thyroglossal duct cyst and goitre on nuclear thyroid scan: A case report

The PTS scan aimed to determine whether this was the only thyroid gland in the patient since the cystic lesion was within the thyroid gland and the possibility to remove the entire diseased thyroid gland along with the cyst was high based on the preoperative assessment. [...]the decision to search for ectopic and functional thyroid tissue is important before surgical care. The cystic mass measured 14 x 10 x 15 mm, had a volume of 1.2 ml in the anterior neck, was attached to the thyroid isthmus and displaced the right thyroid lobe inferiorly, and was of normal colour flow Doppler interrogation, thereby confirming the potential for a TGDC. In the management of TGDC, FNAC is reported as being safe and cost-effective in differentiating benign from malignant lesions.7 In the process of making a correct diagnosis of suspected TGDC, one must ascertain the presence of the thyroid gland and ensure that the only thyroid tissue is not within the cyst to be removed. The subsequent distinction between the TGDC and goitre was difficult since the increased uptake on PTS corresponded to both visible neck swelling and the thyroid gland. [...]differential diagnoses included ectopic thyroid, TGDC, or TGDC with viable thyroid tissue.