Reoperative parathyroid surgery in the era of sestamibi scanning and intraoperative parathyroid hormone monitoring.

HYPOTHESIS Results of reoperative parathyroid surgery (RPS) have improved with the advent of sestamibi parathyroid subtraction scanning and intraoperative parathyroid hormone (IOPTH) monitoring. DESIGN Retrospective review of patient histories, preoperative localization studies, operative data, including IOPTH monitoring, and outcomes for patients undergoing recent RPS at a single institution. Follow-up was complete (mean, 20 months). SETTING Tertiary care referral center. PATIENTS All patients undergoing RPS for benign persistent or recurrent primary hyperparathyroidism during the period 1989 to 1997. MAIN OUTCOME MEASURES Overall cure rate and operative morbidity from RPS; sensitivity and accuracy of preoperative localization studies; and prediction of cure from IOPTH monitoring. RESULTS The study group included 124 patients (87 women and 37 men). Hypercalcemia was corrected in 109 patients (88%). Permanent recurrent laryngeal nerve injury occurred in 0.8% and permanent hypoparathyroidism in 13% of patients. Test sensitivities and accuracies, respectively, were as follows: ultrasound with biopsy, 90% and 82%; sestamibi parathyroid subtraction scanning, 82% and 67%; and ultrasound alone, 75% and 65%. Level of IOPTH was predictive of cure in all patients with a 70% or greater fall from baseline at 20 minutes after excision. Persistent multigland disease was the major cause for reoperative failure (73%). CONCLUSIONS Neither cure rates nor operative morbidity have changed appreciably over the past 2 decades, despite the introduction of sestamibi parathyroid subtraction scanning and IOPTH monitoring. Multigland disease continues to represent the principal cause of failure in RPS despite the routine use of preoperative localization studies. Thus far, increasing the stringency of IOPTH monitoring from a 50% to 70% decline from baseline levels has been predictive of cure, even in multigland disease. Most missed abnormal glands reside in normal anatomic locations, and the need for multiple operations, not just the reoperation, results in the increased morbidity seen with RPS.