The Preoperative localization of parathyroid adenomas has been a challenge to the roentgenologist. Recent improvement in the methods of clinical and laboratory diagnosis has led to the earlier recognition of these neoplasms. Only rarely is preoperative localization possible by virtue of tracheal or esophageal displacement. Both angiography and pneumomediastinal tomography have been employed in an attempt to improve localization of parathyroid adenomas. Seldinger (10) reported angiographic localization of parathyroid adenomas in 4 of 6 patients and Silinkova-Malkova (11) was successful in 1 of 5. Both authors based localization on displacement of the inferior thyroid artery. Wanke (14) described 1 patient in whom a vascular blush was noted in a parathyroid adenoma in the superior mediastinum on preoperative arteriography. Opacification of 2 additional parathyroid adenomas was seen on direct operative arteriograms of the inferior thyroid gland (7,13). Gross Anatomy The parathyroid glands develop from outgro...