3.3. Operation Method of the Reference Group

The patient was in the right decubitus position, inhalation general anesthesia, abduction fixation of the left upper limb, and headstock. During the operation, the bed structure adjustment and body structure pad height were used to adjust the body position. A 0.5-1.2 cm micro wound was cut in the front abdomen and left abdomen, and carbon dioxide artificial pneumoperitoneum was 2 kPa. The first incision, 1.0 cm, is located in the periumbilical area as the endoscope inlet. The second incision, 1.2 cm, is located at the intersection of the left vertical line of the left central line of the left clavicle in the left middle and upper abdomen, and the third incision, 1.2 cm, is located at the projection area of the left anterior axillary axis through the splenic hilum for splenic ligament dissection and vascular ligation. The fourth and fifth incisions, 1.0 cm, are located at the connecting line between xiphoid process and navel for traction and fixation of the colon and stomach. If necessary, the main operation port can be expanded to 4.0 cm. After the main blood vessels of the spleen are ligated, the ligament tissue is stripped, cut, and taken out. Drainage tube was placed in splenic fossa.