Repositioning of Ureteropelvic Junction in Robot-assisted Laparoscopic Pyeloplasty

Objective: To describe the technique of ureteropelvic junction (UPJ) repositioning in robot-assisted dismembered pyeloplasty as a modified approach during which the UPJ is brought to a new location to facilitate the anastomosis. Materials and Methods: Retrospective review of pediatric and adult cases of robot-assisted laparoscopic pyeloplasty performed between the years 2016 and 2022. In a select group of patients, repositioning of the UPJ was performed. Demographic data, surgical and post-surgical outcomes were compared to a group that underwent classical Anderson-Hynes (AH) dismembered pyeloplasty. Results: Overall, 70 patients underwent robot-assisted laparoscopic dismembered pyeloplasty and were included in the study, with 15 in the repositioning group and 55 in the AH group. The median age of patients included was 26 months (interquartile range (IQR) 7-203). Median operative time was 140 minutes (IQR 129-192) and 170 minutes (IQR 135-207) for the repositioning and AH group, respectively. The indications for UPJ repositioning were high UPJ insertion (n = 8), crossing vessel (n = 5), and renal malformations (n = 2). Clinical significance was shown in the Society of Fetal Urology classification and split renal function postoperatively, respectively (P <.001; P <.01). Postoperatively, both groups showed improvement in anterior posterior diameter (APD) and diuretic T_1/2 (P = 0.48). There was 1 case of surgical failure requiring revisional surgery in the repositioning group (6.6%) and 3 in the AH group (5.5%) (P >.05). Overall, there were 3 cases of Clavien-Dindo Grade 3 complications, all in the AH group (2 cases of urine leak from anastomosis, 1 case of port side hernia). Conclusion: Repositioning of the UPJ is optional in cases when the obstructed UPJ is in a suboptimal anatomical position.