Use of Fluorescent Catheters to Prevent Urological Organ Injury in Minimally Invasive Colorectal Surgery: A Retrospective Study

BACKGROUND/AIM: In minimally invasive colorectal surgery, ureteral and urethral injuries are uncommon, but they can have serious complications leading to significant postoperative morbidity. Fluorescent catheters have recently been introduced to improve the intraoperative visibility of urological organs. However, clinical reports on their use remain limited. This study aimed to evaluate the feasibility and clinical outcomes of fluorescent ureteral and urethral catheters to prevent urological injuries during laparoscopic, robot-assisted, and transanal total mesorectal excision colorectal surgeries. PATIENTS AND METHODS: This retrospective observational study included 13 consecutive patients who underwent minimally invasive colorectal surgery with fluorescent catheter placement at the Hokkaido University Hospital between September 2023 and January 2025. The catheters were visualized using various near-infrared ray imaging systems. The primary endpoint was the occurrence of intraoperative ureteral or urethral injuries; the secondary endpoint was intraoperative visibility of the ureter/urethra. RESULTS: Nine patients received ureteral catheter, two received urethral catheter, and two received both ureteral and urethral catheters for pelvic exenteration. All ureters were clearly identified intraoperatively and no ureteral injuries occurred. In the two urethral catheter cases performed for urethral preservation, the catheter was not directly visible from the surgical field during transanal total mesorectal excision, suggesting a lack of proximity, and urethral preservation was achieved. In the two pelvic exenteration cases, both the ureters and urethral were visualized and intentionally resected without inadvertent injury. CONCLUSION: Fluorescent catheterization is a feasible, safe, and practical technique for enhancing intraoperative identification of urological structures in high-risk colorectal surgery. Its use may help reduce the risk of inadvertent injury, particularly in anatomically complex and minimally invasive procedures.