Scintigraphic detection of adenoma in primary hyperparathyroidism.

Ten patients with biochemical and clinical evidence of primary hyperparathyroidism were studied scintigraphically using a double-radionuclide subtraction technique. Preoperative imaging was performed with Sodium pertechnetate Tc 99m and thallium chloride Tl 201 using a gamma camera with a pinhole collimator. The data were stored in a matrix of 64 X 64. The avidity of 201Tl for nodules of the parathyroid gland was demonstrated on analogue and digital images both with and without the subtraction of thyroid tissue. In our ten patients, this technique detected nine out of ten histologically proven adenomas, and missed a relatively small lesion embedded within the thyroid of one patient. This method may have considerable advantages over non-specific or invasive radiodiagnostic methods, and may facilitate the diagnosis and planning of the surgical approach in cases of primary hyperparathyroidism.