MISLEADING IMAGING RESULTS IN THE DIAGNOSIS OF PARATHYROID CYSTS

Enlarged cystic parathyroid glands, whether hyperfunctioning or nonfun ctioning, are rare and their accurate preoperative diagnosis is a diff icult task. The authors report two cases of patients with cystic neck masses studied by Tl-201-Tc-99m pertechnetate subtraction scintigraphy , computerized tomography, and ultrasonography. The diagnostic consens us of preoperative studies was that these lesions were thyroid nodules or parathyroid adenomas. Surgical removal and histopathologic examina tion of these masses revealed a cystic parathyroid gland and a cystic parathyroid adenoma, respectively. When a fluid-filled lesion in the n eck deep to the lower pole of the thyroid gland is encountered, the po ssibility of a parathyroid cyst should be considered so that further d iagnostic tests can be properly performed.