Robotic Low Ligation of the Inferior Mesenteric Artery with Real-Time Identification of the Vascular System for Rectal Cancer using the Firefly Technique

Sung Uk Bae¹, Byung Soh Min², Nam Kyu Kim². ¹Keimyung University and Dongsan Medical Center, ²Yonsei University College of Medicine

Background: Low ligation of the inferior mesenteric artery (IMA), in which the IMA is ligated caudal to the origin of the left colic artery (LCA), has been reported to have several advantages including allowing for in¬creased blood supply to the left colon and the preservation of the au¬tonomic nerve at the IMA origin. In laparoscopic surgery, this procedure is technically demanding and requires a long time to complete. By integrating intraoperative near infrared fluorescence (INIF) imaging into a robotic system, surgeons can identify the vascular anatomy in real-time with the technical advantages of robotics that is useful for meticulous lymphovascular dissection. Herein, we report our initial experience of robotic low ligation of the IMA with real-time identification of the vascular system for rectal cancer using the Firefly technique.
Methods: The robotic system was used by the single docking dual phase technique. A 5 mg sample ofindocyanine green (ICG) dye was injected two times prior to INIF imaging to identify the left colic branch of the IMA and the collateral artery near the inferior mesenteric vein (IMV) and pancreas. Lymphovascular dissection time was measured from the lymph node dissection around the IMA until the sigmoid artery was divided.
Results: The total operation time was 327 min. The low ligation time was 10 min and the time interval between ICG injection and division of the sigmoid artery was 5 min. The estimated blood loss was 200 ml. The time to soft diet was 4 days and the length of stay was 7 days. There were no complications associated with ICG dye administration and no anastomotic leakage occurred. The total number of lymph nodes harvested was 17.
Conclusions: Robotic low ligation of the IMA with real-time identification of the vascular system for rectal cancer using the Firefly technique can be safe and feasible. This technique can allow for precise lymph node dissection along the IMA and facilitate the identification of the left colic branch of the IMA. However, further large-scale comparative studies are needed to prove the advantages of this procedure.