Value of high resolution real-time ultrasonography in secondary hyperparathyroidism

Thirty-two patients were treated surgically for symptomatic secondary or tertiary hyperparathyroidism, and 27 of these patients had high resolution (10 mHz) real-time ultrasonography before parathyroidectomy. This preoperative localization study identified one or more enlarged hyperplastic parathyroid glands in all but one patient who had not had a previous parathyroid operation, and in five of six patients who did have previous parathyroid operations. In both of the patients in whom no parathyroid glands were identified by ultrasonography the only abnormal enlarged parathyroid glands were those situated within the superior mediastinum. When large glands are not observed by ultrasonography in patients with severe secondary hyperparathyroidism, the glands are usually situated in the superior mediastinum, behind the trachea or esophagus, or deeply within the neck. The size of the parathyroid glands correlated positively with the serum parathyroid hormone level and with the severity of the secondary hyperparathyroidism. Thus, the preoperative identification of parathyroid glands by ultrasonography not only localizes the site of most hyperplastic parathyroid glands (70 percent of patients), but also detects those patients who have enlarged parathyroid glands, elevated serum parathyroid hormone levels, and severe secondary hyperparathyroidism. These are the patients who are thus unlikely to respond to further medical therapy.