Patient 1
Patient 1 was a 73-year-old man with sigmoid colon cancer. The patient had no history of laparotomy. The patient's body weight, height, and BMI were 53 kg, 166 cm, and 19.5 kg/m2, respectively. Laparoscopic sigmoidectomy was performed. The sigmoid colon extensively adhered to the left abdominal wall to the left pelvic wall, and the small intestinal mesentery at the terminal ileum extensively adhered to the sigmoid colon (Fig. 1a). The descending colon was not fixed and was located slightly to the left of the midline (Fig. 1b). The adhesions were peeled off as much as possible. The medial approach proceeded from the vicinity of promontorium, which is normal anatomy, to the cranial side. Because it was difficult to confirm the blood vessel was running, lymph node dissection was performed near the root of the inferior mesenteric artery (IMA). The blood vessel was ligated and cut off on the distal side of the left colic artery (LCA) to maintain blood flow. The operation time was 219 min, and the blood loss was 21 mL.
Patient 2
Patient 2 was a 62-year-old with lower rectal cancer. The patient had no history of laparotomy. The patient's body weight, height, and BMI were 62 kg, 161 cm, 22.5 kg/m2. Robot-assisted intersphincteric resection was performed. Because of an abnormal fixation, the descending colon was located slightly to the left of the midline. No descending colon was present in the left flank, and the peritoneal organ, left gonad, and ureter were visible (Fig. 2a). The sigmoid colon is displaced to the right and adhered to the appendix, ascending colon, and terminal ileum. The adhelysis was laparoscopically performed before the docking to the robotic system (Fig. 2b,c). Although it was difficult to remove the adhesions due to abnormal fixation, the IMA root was identified and then ligated and cut at the same site. The operation time was 525 min, and the blood loss was 80 mL.
Patient 3
Patient 3 was a 76-year-old man with lower rectal cancer. The patient's body weight, height, and BMI were 52 kg, 155 cm, 22.0 kg/m2. The patient had a combination of esophageal cancer and lung cancer. The patient underwent robotic Hartmann's operation with lymph node dissection in the D2 range. It was not fixed because of an abnormal fixation of the descending colon. Moreover, the sigmoid colon was extensively and strongly adherent to the small intestinal mesentery of the midline (Fig. 3a,b). Because of the wide range of adhesions, the robot was docked after the adhesions were detached as much as possible under the laparoscope. After dissection of the adhesions, the anatomy around the IMA was recognized, and then a rectal dissection was performed first. After confirming LCA, sigmoid artery (SA), and superior rectal artery (SRA) from IMA, blood flow was blocked at the planned incision site with vascular clamp forceps; indocyanine green (ICG) fluorescence imaging was used to confirm that there was no blood flow disorder in the remaining planned intestinal tract (Fig. 3c,d). A retroperitoneal incision was made to expose the IMA root from the cranial side of the promontorium, which is normal anatomy. However, because it was difficult to identify the tissue layer in the retroperitoneum, we changed to the lateral approach midway through, identified the gonadal arteries and veins and the ureter from the outside, and performed ablation from the outside. The operation time was 415 min, and the blood loss was 25 mL.
In all patients, we confirmed that the intestinal blood flow was good by using ICG fluorescence imaging before anastomosis.