The Value of the Selenomethionine Se 75 Scan in Preoperative Localization of Parathyroid Adenomas

Abstract

The selenomethionine Se 75 scan was performed in 42 patients with a clinical diagnosis of hyperparathyroidism. The scan correctly localized the abnormal gland in 13 of 23 patients with proven parathyroid adenoma. The parathyroid scan was not helpful in seven patients with parathyroid hyperplasia. Size was the most important factor contributing to visualization of parathyroid adenomas. Adenomas larger than 2 gm were consistently visualized while those weighing less than 1 gm were commonly not detected by the scan. High background over the mediastinum precludes the possibility of detecting most mediastinal adenomas by this technique. The value of the selenomethionine Se 75 parathyroid scan is thus limited in patients with small adenomas or hyperplastic glands and in patients with adenomas or hyperplastic glands lying deep in the thorax.