[Intraoperative Indocyanine Green Fluorescence to Assure Vital Parathyroids in Thyroid Resections]. / Intraoperative Indocyaningrün-Fluoreszenzbildgebung zur Sicherung vitaler Nebenschilddrüsen bei Schilddrüsenresektionen.

INTRODUCTION: 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. MATERIALS UND METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Indocyanine Green Tissue Angiography Can Reduce Extended Bowel Resections in Acute Mesenteric Ischemia.

PURPOSE: Surgical exploration and bowel resection are frequently required for treating non-occlusive mesenteric ischemia. Intraoperative evaluation of intestinal perfusion is subjective and challenging. In this feasibility study, ICG fluorescence angiography was performed in order to evaluate intestinal perfusion in patients with acute mesenteric ischemia. METHODS: This is a retrospective analysis of 52 patients who were operated for acute mesenteric ischemia using ICG fluorescence angiography. Patients with occlusive disease requiring recanalization were excluded. The SPY and PinPoint imaging systems were used for open and laparoscopic surgery, respectively. Intraoperative macroscopic assessment of perfusion was compared with the ICG angiography results. RESULTS: Surgical exploration was performed for ischemia of the colon (n = 12), the small bowel (n = 23), or both (n = 16). One patient had ischemia of the esophagus and stomach. All patients had a preoperative CT angiography to rule out stenosis or occlusion of the mesenteric vessels. In 18 cases (34.6%), ICG fluorescence angiography provided information that was supplemental to macroscopic evaluation, but most patients did not survive the postoperative course. However, in six of those cases (11.5%), ICG angiography led to a major change in operative strategy resulting in a significant clinical benefit for those patients. For two cases, ICG fluorescence produced false negative results. DISCUSSION: ICG tissue angiography is feasible and technically reliable for evaluating intestinal perfusion in acute mesenteric ischemia and led to a significant clinical benefit in 11% of our patients. A relevant discrepancy between surgical visual assessment and fluorescence angiography was found in 35% of the cases, which may help to define resection margins more accurately and thus support surgical decision-making.