Clinical usefulness of intraoperative parathyroid hormone monitoring for primary hyperparathyroidism

Purpose The availability of intraoperative parathyroid hormone (IOPTH) monitoring allows successful focused parathyroidectomy for primary hyperparathyroidism (pHPT). The objective of this study was to report our initial experience in IOPTH monitoring during parathyroid surgery for primary hyperparathyroidsim. Methods Between May 2011 and February 2013, 37 patients underwent focused parathyroidectomy due to pHPT. IOPTH monitoring based on Miami criteria was used to confirm complete excision of hyperfunctioning parathyroid gland during surgery. Medical records of patients were reviewed retrospectively. Results Preoperative mean maximal calcium level was 11.7 ± 0.9 mg/dL. Preoperative technetium (99mTc) sestamibi scan and ultrasonography identified 32 of 37 (86.5%) and 29 of 37 (78.4%) of abnormal parathyroid glands, retrospectively. Results of the 2 imaging modalities were discordant for 8 cases (21.6%). The mean pre-excision PTH level was 147.2 ± 201.5 pg/mL. At 5- and 10-minute post tumor resection, PTH levels were 65.3 ± 25.4 pg/mL and 47.5 ± 24.3 pg/mL, respectively. In all cases, IOPTH levels fell by at least 50% after removing all suspected abnormal glands. All patients had a successful return to normocalcemia after surgery (mean follow-up period: 60.2 ± 15.4 months). Conclusion Surgeon could confirm complete excision of abnormal hyperfunctioning parathyroid glands by IOPTH monitoring during surgery for pHPT. IOPTH monitoring can maximize performance of successful focused para thyroidectomy for pHPT, especially when preoperative imaging results are discordant.