A Novel Robot‐Assisted Laparoscopic Pyeloplasty Technique to Ensure Secure Anastomosis for Lower Pole Ureteropelvic Junction Obstruction in a Patient With an Incomplete Duplicated Collecting System

Introduction Ureteropelvic junction obstruction (UPJO) in patients with a duplicated collecting system is rare, and evidence on robot‐assisted laparoscopic pyeloplasty (RALP) and technical strategies for end‐to‐side pyeloureterostomy in such cases remains limited. Materials and Surgical Technique We present technical refinements used during RALP in a patient with an incomplete duplicated collecting system. First, an open‐ended ureteral catheter was used to guide accurate ureteral incision and secure anastomosis. Second, the dorsal pelvis of the lower pole was anastomosed to the larger‐caliber common ureter rather than the narrow upper pole ureter. To ensure a tension‐free anastomosis, the kidney and pelvis were mobilized as needed. Third, an M‐shaped traction technique was applied during posterior wall suturing: the lateral stay suture was tied, while the medial one was left untied and retracted with a bulldog clamp to create a groove, enhancing lumen visibility and enabling continuous posterior suturing under direct vision. Discussion This case demonstrates the feasibility of end‐to‐side pyeloureterostomy for UPJO with incomplete duplication using robotic techniques. Key modifications—catheter‐assisted incision, anatomical mobilization, and M‐shaped traction—allowed for precise anastomosis. Further case accumulation is needed to validate these strategies for similar anatomical variations.