Radioimmunoassay of parathyroid hormone contained in venous catheter samples from the major veins of the neck and thorax in patients with primary hyperparathyroidism has permitted preoperative localization of the source of excess hormone secretion in 28 (56%) of 50 patients. Results show that the technique has many advantages over other methods for preoperative parathyroid localization.
Powell D, Murray TM, Pollard JJ, Cope O, Wang C, Potts JT. Parathyroid Localization Using Venous Catheterization and Radioimmunoassay. Arch Intern Med. 1973;131(5):645-648. doi:10.1001/archinte.1973.00320110029003