Minimal invasive approach for lower pole uretero-pelvic junction obstruction (UPJO) in duplication anomaly: A multi-institutional study

Purpose: We present a multi-institution experience of laparoscopic and robotic-assisted reconstruction approach of lower-pole UPJO (ureteropelvic junction obstruction) in duplicated collecting systems. Methods: Retrospective review of patients who underwent laparoscopic or robotic pyeloplasty for lower pole UPJO between 2011 and 2020. Patient demographics, perioperative surgical data, complications and outcomes are described. Surgical approach was adjusted to the anatomic variant. Success was defined as improved hydronephrosis, indicated by improved Society of Fetal Urology classification at 9 months follow up. Results: Forty-one patients underwent MIS reconstruction surgery of lower pole UPJO (38- laparoscopy, 3- robot assisted). Median age at surgery was 13 months (IQR, 5–32). Mean operative time was 80 min (IQR, 70–110). There were no intraoperative complications, no conversions and estimated blood loss was negligible. Lower pole dismembered pyeloplasty was performed in 19 (46%) patients, uretero-pyelostomy (lower pole pelvis to upper pole ureter) in 15 (36.5%), concomitant obstruction of the upper pole moiety was encountered in 4 (10%) patients; lower pole dismembered pyeloplasty and upper pole ureter to lower pole pelvis (end-to-side uretero-pyelostomy) was performed and concomitant ipsilateral upper pole partial nephrectomy was carried out in 3 (7%) patients. Overall, 3 patients had grade 1 or 2 Clavien-Dindo postoperative complications and one patient developed a grade 3 complication. Surgical success was achieved in 38/41 (93%), 3 patients required an additional procedure. Conclusions: UPJO of lower pole of duplication anomaly is highly variable anatomically; therefore, an individualized surgical approach is mandatory. The minimal invasive approach is feasible and safe with good outcomes.