SJLA_2024_A2: Laparoscopic Colectomy with Lymph Node Navigation and Intracorporeal Anastomosis using Double Indocyanine Green Technique
Authors: Wada Toshiaki , Makutani Yusuke , Ogawa Ryotaro , Yoshioka Yasumasa , Iwamoto Masayoshi , Daito Koji , Ueda Kazuki , Tokoro Tadao , Kawamura Junichiro 
Published: September 2024

Introduction:
In laparoscopic colectomy for colorectal cancer, appropriate lymph node dissection and prevention of anastomotic leak are very important. Indocyanine green (ICG) images obtained through the laparoscopic procedure helped visualize lymphatic drainage vessels and inform decision-making to determine the vessels. Intracorporeal anastomosis has advantages such as earlier recovery of postoperative bowel function, shorter length of wound incision, reduction of intestinal mobilization range, and fewer incisional hernias.

Background:
We report the surgical technique and short-term results of 48 patients who underwent laparoscopic colectomy and intracorporeal anastomosis using the double ICG fluorescence technique from July 2020 to September 2023.

Methods:
Two injections of ICG (0.75 mg ×2) into the proximal and distal subserosa of the tumor preceded the surgical procedure after pneumoperitoneum. Intraoperative lymph node mapping by the Stryker1588, 1688AIM camera imaging system was visualized. Laparoscopic colectomy was performed according to the Complete Mesocolic Excision and Central Vascular Ligation concepts. Complete intracorporeal anastomosis was performed by a functional end-to-end or overlap or Delta anastomosis. After anastomosis, ICG (12.5 mg) was injected intravenously to check the intestinal blood perfusion at the anastomosis site.

Results:
Forty-eight patients (Sex; male: 23 and female: 25) (Tumor location; C: 20, A: 11, T: 8, D: 7, S:2) (pStage0:2, I:15, II: 16, III:10, and IV:5) were underwent. The median age was 74. median body mass index was 23. Median number of dissected lymph nodes was 18. The median operative time was 246 min. The median wound length was 3.5 cm. The median postoperative hospital stay was 7 days. Visualization of lymphatic flow was observable in 24 of 28 cases (85.7%). The transection line was changed in 2/48 cases (4.1%) after ICG fluorescence angiography. There were no intraoperative complications, and two patients had postoperative paralytic ileus.

Discussion:
We introduce a novel technique of double ICG administration during laparoscopic colon resection for colon cancer that enables improved lymphadenectomy and warrants the extent of intestinal resection. It contains the intrinsic solution to the potential risks related to more intense dissection for extended lymphadenectomy. This is an immediate assessment of blood supply to the anastomosed intestinal walls. ICG fluorescence has immanent advantages as a result of its very low toxicity, high sensitivity, fast feedback, and absence of radiation. It is helpful to determine the extent of a bowel resection and can avoid leaving positive lymph nodes behind. It was revealed that ICG accurately evaluates the blood supply to anastomotic sites in real time and can detect organ ischemia before reconstruction is performed. This is particularly useful in laparoscopic surgery, as detection of impaired blood supply is difficult and even more for intracorporeal anastomosis. Lower anastomotic leak and reoperation rates were revealed with the use of ICG in several studies. Lymph nodes’ metastases are the most important prognostic factor in colon cancer, which has a poor prognosis and high recurrence. The use of ICG in the identification of lymph flow and lymphadenectomy basin in colon cancer patients has been previously reported. Lymph drainage of the transverse colon is complicated, and understanding this lymphatic drainage system is difficult, making ICG fluorescence particularly useful in right-sided and splenic flexure colon cancer patients.

Conclusion:
ICG fluorescence lymphangiography in laparoscopic colectomy for colon cancer allows visualization of lymphatic flow and may complement more reliable lymph node dissection. In addition, the evaluation of intestinal perfusion using ICG contributes to the reduction of anastomotic leakage and enables safer intracorporeal anastomosis.