Indocyanine green fluorescence-guided robotic Boari flap-pelvis anastomosis for the management of long-segment transplant ureteral stricture: a case series of six patients.

Background: The treatment of transplant ureteral stricture (TUS) has been a great challenge, and there is limited experience with indocyanine green (ICG) fluorescence-guided robotic Boari flap-pelvis anastomosis to identify ureteral stenosis segments (especially long-segment) and their postoperative blood supply. We report case series of ureteral strictures treated with ICG fluorescence-guided robotic Boari flap-pelvis anastomosis in our center.

Case description: We retrospectively collected clinical data of six patients diagnosed with long-segment even full-length TUS who underwent robotic Boari flap-pelvis anastomosis with the assistance of modified distribution of robotic ports and ICG fluorescence between June 2022 and June 2024, focusing on postoperative renal function, stenosis recurrence, and urinary fistulae. All patients, with long-segment even full-length TUS, underwent robotic Boari flap-pelvis anastomosis, with near infrared (NIR) fluorescence imaging using ICG fluorescence injection through the preplaced nephrostomy tube to find the pelvis and ureteric strictures of the transplant kidney. The median operative time was 181.5 min (range, 167-205 min) and the median blood loss was 65 mL (range, 50-120 mL). There were no high-grade complications (III-IV on Clavien-Dindo classification), and no patients were converted to open surgeries. The double-J stent was removed about two months after surgery, then the nephrostomy tube was removed about a week later. After six months of follow-up, no complications such as stenosis recurrence, urinary fistulae and urinary tract infection occurred. In addition, all patients did not complain for dysuria, frequent micturition, urgent urination, dysuria, or other symptoms in the follow-up.

Conclusions: Robot-assisted Boari flap-pelvis anastomosis guided by ICG fluorescence could be considered as a safe and reliable treatment for long-segment TUS. However, a large number of samples and long-term follow-up are still needed to further prove that it is the preferred option.