Applications of Fluorescence Imaging Guided Lymph Node Dissection and Fluorescence Angiography of Inferior Mesenteric Artery Assisted Left Colic Artery Preservation

Inclusion Criteria:

• Patients aged between 18 and 75 years
• Colonoscopic biopsy confirmed colorectal adenocarcinoma
• The tumor was located in the rectum or upper rectum, and the surgical method was Dxion
• No local complications before operation (no obstruction, incomplete obstruction, nomassive active bleeding, no perforation, abscess formation, no local invasion)
• Preoperative imaging diagnosis was cT1-4aNxM0
• The hematopoietic functions of heart, lung, liver, kidney and bone marrow meet therequirements of surgery and anesthesia
• Sign the informed consent form

Exclusion Criteria:

• Previous surgical history of malignant colorectal tumors
• The surgical methods were combined abdominoperineal resection, Hartman operation andISR operation
• There are contraindication of laparoscopic surgery, such as severe cardiopulmonaryinsufficiency
• Patients who have undergone multiple abdominal and pelvic surgeries or extensiveabdominal adhesion
• Patients with intestinal obstruction, intestinal perforation, intestinal bleeding andother emergency operations
• ASA grade ≥IV and/or ECOG physical status score ≥2 points
• Patients with severe liver and kidney function, cardiopulmonary function, coagulationdysfunction or combined with serious underlying diseases can not tolerate surgery
• Have a history of serious mental illness
• Patients with uncontrolled infection before operation