Presentation Authors: Ciro Andolfi*, Diboro Kanabolo, Veronica M. Rodriguez, Joshua M. Aizen, Brittany L. Adamic, Craig V. Labbate, Mohan S. Gundeti, Chicago, IL
Introduction: Hydronephrosis (HN) without obstruction is a common finding in patients awaiting vesicoureteral reimplantation for high-grade vesicoureteral reflux (VUR). Though a common phenomenon, postoperative HN (POHN) still raises concern for some surgeons who fear the presence of silent obstruction. We aim to determine the natural progression and clinical significance of post-operative HN in children who have previously undergone open (OUR) or robot-assisted (RALUR) ureteral reimplantation for VUR.
Methods: We retrospectively reviewed medical records of pediatric patients who underwent OUR or RALUR between December 2007 and December 2017. Baseline characteristics, operative outcomes, and trends in post-operative HN were then compared between OUR and RALUR.
Results: In the 10-year study period, 129 patients met inclusion criteria. 52 (40.3%) patients underwent OUR and 77 (59.7%) patients underwent RALUR. POHN was identified in 21 (40%) of OUR and 21 (27%) of RALUR patients (P=0.1190). In patients with POHN, 15 (71%) OUR and 13 (62%) RALUR patients had no evidence of pre-operative HN. 38/42 (90.5%) of patients with POHN, who were managed by clinical observation, had spontaneous improvement with a mean time to resolution of 381 (+/- 466) days. Mean time-to-resolution of POHN was 553 and 242 days for OUR and RALUR, respectively (P=0.0063). Of 3 patients in the OUR cohort with persistent POHN, 2 had persistent bilateral VUR and underwent redo OUR and 1 had isolated persistent bilateral HN. One patient in the RALUR cohort had persistent bilateral VUR and underwent redo OUR. Bilateral reimplantation was found to be an independent risk factor for both persistent HN and delayed recovery. Overall time-to-resolution of HN was significantly higher in this group compared to unilateral reimplantation (699 vs 216 days, P=0.0035). This finding was seen in both OUR (821 vs 314 days, P=0.0423) and RALUR (502 vs160 days, P=0.0187) groups.
Conclusions: HN following ureteral reimplantation is a common finding. POHN is frequently transient and benign. In most cases it resolves within one year after surgery, supporting the evidence that ureteral obstruction after reimplantation is a rare event. Patients with high-grade pre-operative bilateral VUR and HN requiring bilateral vesicoureteral reimplantation are at higher risk for developing more severe and prolonged POHN and should be closely monitored with imaging studies for resolution of their HN.