Efficiency of Gamma Probe and Dual-Phase Tc-99m Sestamibi Scintigraphy in Surgery for Patients with Primary Hyperparathyroidism

Purpose The purpose of this study was to determine the value of the intraoperative gamma probe and the efficacy of dual-phase Tc-99m sestamibi imaging in patients with primary hyperparathyroidism. Methods Twenty-one patients with primary hyperparathyroidism were examined prospectively. Results of same-day dual-phase Tc-99m sestamibi scintigraphy and intraoperative gamma probe evaluations were compared with the intraoperative findings and histopathologic diagnoses. A 15-mm handheld gamma probe was used to measure gamma activity in the neck and upper mediastinum. Nuclear mapping by gamma probe showed a single quadrant of neck that emitted gamma radiation significantly greater than the other three quadrants, which correlated with the sestamibi scan. Results Dual-phase Tc-99m sestamibi scintigraphy determined and localized parathyroid lesions in 20 patients (sensitivity, 94%). Of the 20 parathyroid lesions removed, 15 were located in normal positions, whereas five were explored in ectopic sites (one within the thyroid, one in the anterior mediastinum, one in a retrotracheal position, one in the carotid sheath, and one in the retroesophageal region). Although the index of thyroid nodules varied from 15.8% to 22.9%, the index for parathyroid lesions was 77.3% to 112.8%. Conclusions These results confirm that parathyroid lesions, especially at ectopic sites, can be treated successfully in shorter operative times with minimal complications with the help of the intraoperative gamma probe.