Critical role of identification of the second gland during unilateral parathyroid surgery: a prospective review of 119 patients with concordant localization.

HYPOTHESIS We aimed to validate the effectiveness of a protocol for primary hyperparathyroidism in which intraoperative parathyroid hormone measurement (IOPTH) was not routinely used during minimally invasive parathyroidectomy for patients with dual localization by technetium Tc 99m sestamibi (MIBI) and ultrasonography and hypothesized that our rate of surgical failure would be less than 3% for patients with concordant localization. DESIGN Prospective cohort study. SETTING Brigham and Women's Hospital, Boston, Massachusetts. PATIENTS One hundred nineteen patients with primary hyperparathyroidism and dual localization. MAIN OUTCOME MEASURES Incidence of surgical cure following minimally invasive parathyroidectomy (MIP) without the use of IOPTH for patients with dual localization. RESULTS A total of 324 patients with primary hyperparathyroidism underwent parathyroid exploration between October 1, 2005, and September 30, 2009. In 136 patients (42.0%), imaging was concordant by MIBI and ultrasonography, and 119 patients were scheduled for MIP. Our protocol for MIP without IOPTH was successful in 115 patients (97%), with 13 cases converted to bilateral exploration based on intraoperative suspicion of multiglandular disease. Eight of 13 conversions (62%) revealed multiglandular disease that was undetected on imaging, 6 of which were apparent from examination of the ipsilateral second parathyroid gland. Four of 136 patients (3%) had persistent postoperative hypercalcemia necessitating reoperation, and all 4 had an adjacent but unseen second adenoma. There was no significant difference in the surgical cure rate following MIP without IOPTH for this prospective study vs a previously published retrospective analysis by our group (97% vs 98%, P = .47). CONCLUSIONS Focused parathyroid gland exploration without IOPTH can be successfully performed in a select group of patients with dual localization by MIBI and ultrasonography. However, identification of the second ipsilateral gland may be critical to ruling out undetected multiglandular disease.