Prediction of hypocalcemia after total thyroidectomy using indocyanine green angiography of parathyroid glands: A simple quantitative scoring system

Background: Hypocalcemia is one of the most common complications after total thyroidectomy. Recently, indocyanine green (ICG) angiography of the parathyroid glands (PGs) has been suggested as a reliable tool for predicting postoperative hypocalcemia. The aim of our study was to evaluate the performance of a simple quantitative score based on ICG angiography of the PGs (4-ICG score) for predicting postoperative hypocalcemia.

Methods: Thirty nine consecutive patients who underwent total thyroidectomy for multinodular goiter were included. For each patient, the 4-ICG score was calculated, adding the individual viability value of the four PGs. Discrimination and correlation analyses were performed.

Results: In 32/39 patients, the four PGs were identified. Patients with postoperative hypocalcemia (n = 6, 19%) had a lower 4-ICG score (2.5 [1.8-3.3] vs. 4.0 [3.0-6.0]; p = 0.003). The 4-ICG score showed good discrimination in terms of predicting postoperative hypocalcemia (AUC = 0.875 (0.710-0.965); p = 0.001) and a good correlation with postoperative parathyroid function.

Conclusions: The 4-ICG score predicts postoperative hypocalcemia and correlates well with postoperative parathyroid function in patients undergoing total thyroidectomy for multinodular goiter.