Intraoperative Indocyanine Green Fluorescence to Assure Vital Parathyroids in Thyroid Resections

Abstract

Total thyreoidectomy is associated with high rates of temporary or permanent hypoparathyroidism. During surgery, ICG fluorescence angiography can be used to detect and preserve well vascularised parathyroid glands; this technique has been recently introduced in retrospective and prospective trials as an intraoperative technical support to avoid postoperative hypoparathyroidism. 27 patients undergoing total thyreoidectomy were prospectively enrolled in our study. The vascularisation of the parathyroid glands was analysed intraoperatively using ICG tissue angiography. 5 mg indocyanine green were intravenously administered. Fluorescence angiography was evaluated in real time using the PinPoint (Novadaq, Canada) imaging system. The study was approved by the local ethics committee. ICG fluorescence angiography was performed uneventfully in all cases. There was no case of postoperative hypoparathyroidism when at least one parathyroid gland with high fluorescence intensity was preserved. In 4 cases, only low fluorescence intensity was detected in the remaining parathyroid glands after completing the resection. All 4 patients received activated vitamin D3 prophylactically. Two of 4 developed symptomatic hypocalcaemia due to temporary hypoparathyroidism. Implementation of ICG fluorescence angiography can help in predicting and therefore preventing postoperative hypoparathyreoidism after total thyreoidectomy. If a well vascularised parathyroid gland with high ICG fluorescence intensity can be secured, calcium substitution and postoperative prophylaxis of hypoparathyreoidism may become obsolete in the future.