Immediate and medium-term results of intraoperative parathyroid hormone monitoring during video-assisted parathyroidectomy.

Hypothesis: Using an intraoperative parathyroid hormone (IOPTH) assay during video-assisted parathyroidectomy by lateral approach is useful in patients with sporadic primary hyperparathyroidism, and the medium-term results of surgery are excellent.

Design: Retrospective study of patients with sporadic primary hyperparathyroidism following video-assisted parathyroidectomy by lateral approach with IOPTH measurement.

Patients: Of 394 patients with sporadic primary hyperparathyroidism, 200 (67%) were eligible for video-assisted parathyroidectomy by lateral approach: patients in whom a single enlarged gland was clearly localized by ultrasonography, sestamibi scintigraphy, or both.

Main Outcome Measures: An IOPTH assay was used in 198 patients. Intraoperative parathyroid hormone was measured at induction, skin incision, ablation, and 5 and 15 minutes after ablation.

Results: The immediate results of the IOPTH assay were true positive in 187 cases (94.4%), true negative in 8 cases (4%), false negative in 2 cases (1%), and false positive in 1 case (0.5%). The overall accuracy of the IOPTH assay was 98.5%. All patients were normocalcemic postoperatively. The median follow-up was 20.5 months in 150 reviewed: 149 patients (99.4%) were normocalcemic, 17 patients (11.3%) had an elevated PTH level with normocalcemia, and 1 patient (0.6%) had recurrent primary hyperparathyroidism.

Conclusions: In our experience, IOPTH monitoring during video-assisted parathyroidectomy by lateral approach is useful in detecting multiple gland disease not suspected by preoperative localization studies. Overall, IOPTH monitoring predicts medium-term normocalcemia with a success rate of 98.5% in patients with sporadic primary hyperparathyroidism.