Role of preoperative localization and intraoperative localization maneuvers including intraoperative PTH assay determination for patients with persistent or recurrent hyperparathyroidism.

Patients with recurrent or persistent primary hyperparathyroidism have increased operative risk because of scarring in the operative field and the frequent presence of an ectopic gland. Preoperative imaging studies will identify the hyperfunctioning parathyroid gland in the majority of circumstances. The best types or combination of imaging tests has not been definitely established. However, because of their wide availability and demonstrated sensitivity, US and sestamibi scans are most commonly obtained. Based on the clinical setting, additional tests including CT or MRI may be useful. In circumstances when the noninvasive imaging modalities are inconclusive, invasive imaging tests including selective angiography venous sampling and/or direct fine needle aspiration should be used. IOUS, MIRP, and intraoperative PTH determination are useful adjuncts to the safe and successful conduct of reoperative parathyroid surgery: however, the benefit of the routine use of these modalities in reoperative parathyroid surgery has yet to be critically determined.