[Scintigraphic display of an ectopic parathyroid adenoma using 99mTc-MIBI--2 case reports]

Radionuclide imaging of the parathyroid gland is used in the preoperative localization of parathyroid adenoma. Until recently radionuclide imaging of parathyroid tumors was performed using a dual-tracer subtraction technique with 201TI and 99mTcO4-. As an alternative radionuclide imaging with 99mTc-sestamibi (MIBI) has been introduced some years ago. The utility of preoperative parathyroid localization lies in its ability to direct surgical exploration, particularly of ectopic localizations. We present two cases of parathyroid adenoma in which radionuclide imaging with 99mTc-MIBI was successful in detecting atypical locations. In the first case remaining primary hyperparathyroidism was caused by a mediastinal gland. The second case suffered from a recurrence of secondary hyperparathyroidism caused by hyperplasia of the autotransplanted gland after removal of all four parathyroid glands.