The Effectiveness of Radioguided Parathyroidectomy in Patients With Negative Technetium Tc 99m–Sestamibi Scans

BACKGROUND: Many surgeons have shown that radio-guided resection of parathyroid glands can facilitate intraoperative localization in selected patients with primary hyperparathyroidism, especially in the reoperative setting. However, in patients with negative technetium Tc 99m-sestamibi (hereafter referred to as "sestamibi") scans, the usefulness of the gamma probe is unclear. Thus, we were interested in determining the role of radio-guided techniques in patients with primary hyperparathyroidism and negative or nonlocalizing sestamibi scans. DESIGN: Retrospective analysis of a prospective parathyroid database. SETTING: Academic medical center. PATIENTS: Seven hundred sixty-nine patients with primary hyperparathyroidism who had a sestamibi scan and underwent surgical invention by a single surgeon. All patients had radioguided parathyroidectomy using a handheld gamma probe. MAIN OUTCOME MEASURES: Radioactive counts, eucalcemia rate, and complications were compared between patients with positive and patients with negative sestamibi scans. RESULTS: All enlarged parathyroid glands were localized with the gamma probe in patients with a negative or with a positive sestamibi scan with similar sensitivities. This occurred despite the fact that smaller parathryoid glands were present, on average, in patients with negative sestamibi scans (428 mg vs 828 mg, P = .001). Equivalent high postoperative eucalcemia rates (>98%) and low complication rates (0.5%) were achieved with radioguided techniques in both patient populations. CONCLUSIONS: Radioguided techniques are equally effective in patients with negative (nonlocalizing) sestamibi scans undergoing parathyroidectomy for primary hyperparathyroidism. Moreover, use of the gamma probe led to the detection of all parathyroid glands, including ectopically located ones. These data suggest that the gamma probe has an important role for localization of parathyroid glands in patients with negative preoperative sestamibi scans.