Department of Radiology and St. Michael's Hospital, University of Toronto, Toronto, Canada
Parathyroid adenomas, or hyperplasia may be present in patients with hypercalcemia. Treatment Is by surgical excision, but about 10% of the lesions may be In ectopic locations. Pre-operative localization of the lesions with non-lvasive imaging, using radionuclides, ultrasound, CT, or MR], may simplify surgery, and reduce patient morbidity. However, the reports of the accuracy of the currently available techniques have shown wide variations. This problem Is reviewed, with emphasis on the radionuclide methods of duai radiopharmaceutical thailium-pertechnetate subtraction, and sestamibi delayed Imaging protocols. The author recommends the routine use of sestamibi, with additional non-Invasive imaging techniques to be added If the original scan Is negative.