We followed up 250 patients surgically treated for hyperparathyroidism. Selective venous catheterization with radioimmunoassay was an effective method of preoperative localization, but its greatest contribution was in patients needing reexploration of the neck. Because of a 15% incidence of multiple gland involvement, we tried to identify all glands, if possible. If more than one gland was abnormal, it also was removed. If three or four glands were abnormal, a subtotal parathyroidectomy was done.
Five patients showed persistent hyperparathyroidism because of failure to find or remove all hyperfunctioning tissue: two patients were successfully treated at a third operation; one has not undergone reexploration, and two have parathyromatosis. Only one patient developed late recurrent hyperparathyroidism. The removal of a single adenoma is adequate providing the remaining glands are grossly and histologically normal. Hypoparathyroidism is a potential, although uncommon, risk following subtotal parathyroidectomy.