The anatomical value of technetium-thallium subtraction scanning in detection and location of parathyroid adenomas.

99mTechnetium-201Thallium subtraction scanning was performed in 24 patients with primary (N = 5) and secondary (N = 19) hyperparathyroidism. The preoperative scintigraphy (N = 12) detected 21 of 23 enlarged glands surgically removed and was helpful for detecting abnormal location especially in the mediastinum. Postoperative scanning in patients with recurrent hyperparathyroidism confirmed the excessive growth of the remaining half parathyroid after subtotal parathyroidectomy or a missing fifth parathyroid after total parathyroidectomy and autotransplantation. False negative results were due to tumor hyperplasia. The technique is recommended prior to repeated exploration in patients presenting persistent disease to predict the location of adenomas generally unsuccessfully detected by ultrasonography and computed tomography.