[Intraoperative parathyroid hormone measurement in patients with primary hyperparathyroidism; particularly valuable for suspected solitary parathyroid adenoma and re-operation]

OBJECTIVE: Analysis of the value of intraoperative parathormone (PTH) measurement in patients with primary hyperparathyroidism. DESIGN: Prospective study. METHOD: Evaluation of the value of intraoperative measurement ofPTH in 75 patients (including 19 patients with multiple endocrine neoplasia(MEN)-1 syndrome) who underwent parathyroidectomy in 2001-2005. RESULTS: The so-called Miami-criterion (PTH concentration 10 min after excision at least 50% below the value measured prior to the first incision) correctly predicted the success of the operation in 91% of the subjects. The success rate was correctly predicted as follows: in subgroups of patients with MEN-1 syndrome, 85%, patients after exclusion of MEN-1, 94%, and patients in whom a solitary adenoma was likely after preoperative localization studies, 97%. In 13% of the total number of operations, PTH-measurements led to further exploration, removal of additional parathyroid tissue and normocalcemia postoperatively. In patients without MEN-1 syndrome, in whom a solitary adenoma was likely on the basis of preoperative investigations, it was possible to limit the operation to a unilateral procedure in 87%. CONCLUSION: In the majority of patients with primary hyperparathyroidism, intraoperative PTH-measurement in combination with preoperative imaging studies leads to patients being cured with a unilateral instead of a bilateral operation.