V9-12: Robotic-assisted pyeloplasty in two patients with duplex kidneys and lower pole uretero-pelvic junction obstruction but differing distance to the ureteral junction

Video

Introductions and Objectives
Ureteral duplication combined with uretero-pelvic junction obstruction (UPJO) is a rare clinical constellation, typically affecting the lower moiety. In patients with the ureteral junction in proximity to the UPJO, the surgical treatment requires more attention. Understanding of the local anatomy and blood supply is mandatory to perform successful reconstruction.

Methods
Our video illustrates preoperative work up, surgical management and follow-up in two patients with an UPJO of the lower moiety in a left duplex kidney but with differing proximal incomplete ureteral duplications. Retrograde uretero-pyelography with consecutive DJ-stent placement was performed prior to pyeloplasty. The first patient revealed a short (5mm), the second a long lower pole (60mm) ureteral length. Besides the optical port, 2 robotic and a 5mm assistant trocar were used for the trans peritoneal approach with the patients in a flank position. Following reflection of the descending colon, the duplicated ureters were dissected cranially. The stenotic ureteral segments were resected and the ureters spatulated over 1.5cm. _x000D_ In the patient with the short ureteral segment, the enlarged lower pole pyelon was reduced in size. In order to prevent ischemic complications, this ureteral segment was resected and an upper to lower pole uretero-pyelostomy was performed. Finally, the pyeloplasty was confected. _x000D_ In the second patient with the long lower pole ureteral segment, a standard pyeloplasty for the lower moiety was performed.

Results
Surgical time was 3.5 hours, estimated blood loss 50 ml and length of hospital stay 5 days in both patients. Intravenous urography after 3 months showed symmetric nephrographic and urographic phases. Both patients are free of symptoms since they underwent surgery.

Conclusions
Robotic assisted surgery is a successful approach for the treatment of a lower pole UPJO in a duplex kidney. Careful preoperative imaging is essential to understand the local anatomy. Specifically, the length of the ureteral segment between the UPJO and the ureteral junction determined the reconstructive approach. In addition, intraoperative findings may impact the surgical strategy.

Funding: none