A clinical trial to evaluate the usefulness of intraoperative intestinal blood f low assessment using anendoscope for the gastrointestinal tract

Interventions: Observation of the serous surface of the colon usin g an endoscope before anastomosis in colorectal cancer surgery Primary outcome(s): Difference in blood flow boundary between ICG m ethod and this method (mm) Study Design: single arm study, open(masking not used), uncontrolled control, single assignment, diagnostic purpose