[Camera inversion technique in laparoscopic sphincter-preserving surgery for mid to low rectal cancer]

Objective: To explore the application of the camera inversion technique in laparoscopic sphincter-preserving surgery for mid to low rectal cancer. Methods: A retrospective study with historical controls was conducted on patients with non-metastatic mid to low rectal cancer which received laparoscopic total mesorectal excision at Peking Union Medical College Hospital from January 2019 to June 2024. The experimental group (2021.7-2024.6) utilized the camera inversion technique (rotating the lens 180° to position the bevel upward and switching the system to reverse display mode for improved visualization and operative angles) during key surgical steps (such as intraoperative mobilization of the mid-to-lower rectum and anastomosis), while the control group (2019.1-2021.6) did not. Clinical data and surgical videos were collected to analyze indicators like operative time, blood loss, mesorectal integrity, surgical complications, and postoperative hospital stay. Results: A total of 624 patients with non-metastatic mid to low rectal cancer were included, including 412 males and 212 females, with an average age of 59.8 years and an average tumor distance of 5.6 cm from the anal verge. The experimental group comprised 301 patients, while the control group had 323 patients.The proportion of abdominal ISR (intersphincteric resection) was significantly higher in the experimental group [19.3% (58/301) vs. 10.2%(33/323), χ²=10.140, P=0.001], with a reduction in operative time [(161.8±67.8) minutes vs. (150.2±68.5) minutes, t=2.134, P=0.033] and a decrease in postoperative hospital stay [(7.8±2.1) days vs. (8.3±3.4) days, t=2.003, P=0.046]. The experimental group also demonstrated advantages in intraoperative blood loss, mesorectal integrity rate, and postoperative complications such as urinary retention, though these differences were not statistically significant (all P>0.05). Conclusion: In laparoscopic surgery for mid to low rectal cancer, using camera inversion technique during distal rectum dissection and transanal anastomosis can provide better surgical field exposure, facilitate precise operations within the correct anatomical plane, and minimize collateral damage. The camera inversion technique is safe and effective.