J. Zagzag1, R. Rokosh1, K. S. Heller1, J. Ogilvie1, K. Patel1, A. Kundel1 1New York University School Of Medicine,New York, NY, USA
Introduction: One major risk of total thyroidectomy is permanent hypoparathyroidism, and this risk may be increased if a central neck dissection is also performed. This study was undertaken to evaluate whether identification of parathyroid glands intraoperatively during total thyroidectomy (TT) and total thyroidectomy with central neck dissection (TTCND) is related to inadvertent parathyroid gland excision in the final pathologic specimen. We also assessed the effect of intraoperative and pathologic parathyroid identification on rates of permanent hypoparathyroidism.
Methods: A retrospective review of all TT and TTCND performed by our endocrine surgery group between 2011 and 2015 was performed. Patients were stratified into two groups, those with 0-2 and those with 3-4 parathyroid glands identified intraoperatively. The presence of any parathyroid tissue in the final pathologic specimen was examined. Intraoperative and pathologic parathyroid identification was correlated with permanent hypoparathyroidism. Chi-squared test was used for statistical significance.
Results: A total of 496 cases included 351 TT and 145 TTCND. At least 3 parathyroid glands were identified intraoperatively in 63% of cases. 37% of final specimens contained unexpected parathyroid glands. Intraoperative identification of 3-4 parathyroid glands was inversely related to the number of parathyroid glands identified on pathology in TTCND but not TT (RR 0.34, 95%CI 0.17-0.69, p-value 0.003). Parathyroid gland identification intraoperatively had no relationship to rates of permanent hypoparathyroidism in either group (TT 2.2% vs 3.8%, p-value 0.721, TTCND 4.1% vs 0.0%, p-value 0.213). Parathyroid tissue on final pathology had no relation to rates of permanent hypoparathyroidism (3.3% vs 2.5%, p-value 0.138).
Conclusion: Intraoperative identification of parathyroid glands is associated with a lower incidence of unexpected parathyroid gland excision when performing a total thyroidectomy with central neck dissection. Total thyroidectomy with or without central neck dissection, when performed by experienced endocrine surgeons who routinely identify parathyroid glands, was not associated with increased rates of hypoparathyroidism when fewer than three parathyroid glands were identified intraoperatively or when parathyroid tissue was found on final pathology. The identification of parathyroid glands intraoperatively did not result in permanent hypoparathyroidism.