Clinical Application Of Indocyanine Green Fluorescence Imaging In Laparoscopic Radical Gastrectomy

Objective:With the promotion of precision medicine and the improvement of the laparoscopic device,indocyanine green fluorescence imaging technology is being gradually applied in laparoscopic radical gastrectomy.However,its application is still in an early stage,lacking large samples,prospective studies,and high-level clinical evidence.Therefore,we conducted this study to evaluate the safety and efficacy of indocyanine green fluorescence imaging technology in tumor localization,resection margin determination,lymph node dissection,and gastrointestinal blood supply evaluation during laparoscopic radical gastrectomy,and to provide reference and evidence for the application of indocyanine green in laparoscopic radical gastrectomy.Methods:This is a non-randomized concurrent controlled trial.Patients who were scheduled to undergo laparoscopic radical gastrectomy in the Department of Gastrointestinal Surgery of Shandong University Qilu Hospital from January 2020 to December 2022 were included and divided into the indocyanine green group and control group.Patients in the Indocyanine green group underwent endoscopy one day before surgery,and indocyanine green solution 1.0ml with a concentration of 0.625mg/ml was injected into the submucosa on both sides of the tumor,oral side,and anal side.Both groups underwent laparoscopic radical gastrectomy and D2 lymph node dissection.The baseline data,postoperative recovery and complications,tumor location,resection margin,indocyanine green fluorescence range,lymph node dissection,gastrointestinal blood supply,and other clinicopathologic data of the two groups were compared.Results:(1)A total of 230 patients were included in this study.115 patients received indocyanine green fluorescence-guided laparoscopic radical gastrectomy and 115 patients received conventional laparoscopic radical gastrectomy.No significant difference in baseline clinicopathologic data was observed between the two groups.(2)Indocyanine green injected around the tumor gradually diffuses to form a circular fluorescent region in which the tumor is centered.Indocyanine green fluorescence diffusion distances were 4.5(3.9,5.3)cm in total gastrectomy and 4.1(3.6,4.9)cm in distal gastrectomy.The tumor was located and resected by reference to the fluorescence range.In patients undergoing total gastrectomy,the indocyanine green group had a proximal margin of 2.7(2.0,3.5)cm and a distal margin of 7.6(4.8,9.0)cm,and the control group had a proximal margin of 2.6(2.1,3.3)cm and a distal margin of 7.3(5.3,9.4)cm.In patients undergoing distal gastrectomy,the indocyanine green group had a proximal resection margin of 4.4(3.6,5.3)cm and a distal resection margin of 2.6(2.0,4.0)cm,and the control group had a proximal resection margin of 4.7(4.0,5.8)cm and a distal resection margin of 3.5(2.0,4.0)cm.There were no significant differences in the resection margin distance between the indocyanine green group and the control group(P>0.05).(3)In this study,the total number of lymph nodes dissected was 39.0(33.0,50.0)in the indocyanine green group and 35.0(30.0,42.0)in the control group.The total number of lymph nodes was significantly higher in the indocyanine green group than in the control group(P=0.001).In addition,the number of lymph nodes at the D1 station was significantly higher in the indocyanine green group than in the control group[25.0(21.0,31.0)vs.22.0(20.0,26.0),P=0.001].The number of lymph nodes at the D2 site was also significantly higher in the indocyanine green group than in the control group[14.0(12.0,20.0)vs.13.0(10.0,15.0),P=0.001].(4)The operation time of the indocyanine green group was 212.0(180.0,235.0)minutes,and that of the control group was 225.0(202.0,252.0)minutes.The operation time of the indocyanine green group was significantly shorter than that of the control group(P=0.001).The median blood loss during the surgery in the indocyanine green group and control group was 51.0(47.0,58.0)ml and 61.0(55.5,66.0)ml,respectively.The intraoperative blood loss in the indocyanine green group was significantly less than that in the control group(P<0.001).(5)Indocyanine green fluorescence was used to evaluate the blood supply of the gastrointestinal tract,anastomosis,and duodenal stump,and the Sherwinter score in all patients was≥3.(6)No gastrointestinal ischemia,anastomotic leakage,or duodenal stump leakage occurred in the indocyanine green group.In the control group,1 case of duodenal stump leakage and 1 case of anastomotic hemorrhage occurred.There were no significant differences in the incidence and severity of postoperative complications between the 2 groups(P>0.05).Conclusions:(1)After the submucosal injection of indocyanine green was performed before surgery,the tumor location,the scope of resection,and the surgical method could be guided through the fluorescence area.The oncological safety of indocyanine green fluorescence in determining the proximal resection margin was verified.(2)Indocyanine green fluorescence could be applied for lymph nodes mapping and anatomical structure identification,to conduct a more accurate and systematic dissection of lymph nodes.(3)After the reconstruction of the gastrointestinal tract,the blood supply can be evaluated by observing the fluorescence distribution of the remnant digestive organs,duodenal,stump,and anastomosis,to reduce the occurrence of gastrointestinal ischemia.(4)The application of Indocyanine green fluorescence can accelerate the operation process and reduce the risk of intraoperative bleeding.In conclusion,the application of indocyanine green fluorescence imaging technique in laparoscopic radical gastrectomy is safe,reliable,and has broad prospects.