Application Of Indocyanine Green(ICG) Fluorescence Imaging In Thyroid Surgery To Protect Parathyroid Glands And Predict Postoperative Hypocalcemia

Objective:To explore the effect of ICG fluorescence imaging technology on the identification of parathyroid glands and prediction of postoperative hypocalcemia.Methods:1.Prospectively enrolled 72 patients with papillary thyroid carcinoma(P TC)who underwent total thyroidectomy and bilateral central lymph node dissection from December 1,2019 to December 31,2020.The experimental group and the control group were each 36 cases.The experimental group used ICG fluorescence imaging to find the parathyroid glands.Before the end of the operation,ICG fluorescence imaging was performed on the identified parathyroid glands and the fluorescence intensity was scored.The control group identified the parathyroid glands based on the naked eye and experience.When suspicious parathyroid glands are found,PTH immune colloidal gold test paper is used to identify parathyroid glands.2.Compare the two groups of parathyroid glands,operation time,preoperative,first day after operation(POD1),third day after operation(POD3),6 weeks after operation(POD42)parathyroid hormone and blood calcium levels,The number of cases of postoperative hypocalcemia,the number of cases of permanent hypoparathyroidism.To study the relationship between ICG score and the occurrence of postoperative hypocalcemia.Results: 1.A total of 116 parathyroid glands were found in the experimental group and 87 parathyroid glands were found in the control group,which was statistically different(χ 2=14.037,P=0.000);2.A total of 114 upper parathyroid glands were found(79.2 %),89 inferior parathyroid glands were found(61.8%),which was statistically different(χ2=10.432,P=0.001).3.Before the operation,the serum calcium and PTH levels of POD1,POD3 and POD42 were not statistically different between the two groups(P>0.05).4.There were 7 cases(19.4%)in the experimental group of transient hypocalcemia and 8 cases(22.2%)in the control group,there was no statistical difference(χ 2=0.070,P=0.791).There was no permanent hypoparathyroidism in either group.In the experimental group,there were 8patients with ICG score ≤ 3 points,including 6 cases of hypocalcemia;28cases of patients with ICG score> 3,including 1 case of hypocalcemia,with statistical difference(χ2=20.267,P=0.000).A total of 29 patients had at least one parathyroid ICG fluorescence score of 2,including 1 hypocalcemia;7patients with a parathyroid ICG score less than 2,including 6 hypocalcemia,There is a statistical difference(χ2=24.364,P=0.000).Conclusions:1.ICG fluorescence imaging technology is helpful for the identification of parathyroid glands.2.The ICG fluorescence intensity score can evaluate the parathyroid blood perfusion and predict the occurrence of postoperative hypocalcemia.