Presentation Authors: Esther Kim, Jeffrey White, Kunj Sheth, Rodolfo Elizondo, Truc Baccam, Houston, TX, Minki Baek, Seoul, Korea, Democratic People's Republic of, Chester Koh*, Houston, TX
Introduction: Open ureteral reimplantation (OUR) is the gold standard for surgical correction of vesicoureteral reflux (VUR), and transient post-operative hydronephrosis (HN) has previously been noted in up to 28% of patients and can take 1 to 2 years to resolve. Robot-assisted laparoscopic ureteral reimplantation (extravesical) (RALUR EV) has become a minimally invasive alternative to OUR. Post-operative HN can be a sign of serious complications, such as urine leak and/or obstruction of the ureter that warrants intervention. However, previous studies have shown that de-novo mild to moderate (SFU grade 1- 3) HN after OUR is not predictive of final differential renal function. We hypothesized that de-novo HN after pediatric RALUR EV will behave similarly to de novo HN after open surgery.
Methods: We reviewed the perioperative parameters of a prospective cohort of children who underwent stent-less RALUR-EV for primary VUR. The severity of de-novo HN was assessed using the SFU grading system via renal ultrasound (US) at the 1-month post-operative follow-up. Renal US was performed every six months until the resolution of HN. Operative success was defined as complete resolution of VUR on the voiding cystourethrogram at the 4-month post- operative follow-up. Patients with other associated urinary tract pathology and patients lost to follow-up were excluded from the study.
Results: A total of 122 kidney units (87 patients) with primary VUR who underwent RALUR-EV met the inclusion criteria. SFU grade 1-3 HN was noted in 30.3% (36/119) of kidney units on the 1-month renal US post-operatively, but 83.9% (26/31) cases of HN completely resolved in a median time of 7.9 months (range 3.4 to 17.6), and 80% (4/5) cases of unresolved HN were downgraded to grade 1 without the need for intervention. Logistic regression showed that an increase of one VUR grade increased the risk of developing de-novo hydronephrosis by 81.4% (p=0.0086).
Conclusions: De-novo post-operative hydronephrosis develops in approximately one-third of pediatric patients after RALUR-EV and is transient, which is similar to hydronephrosis after open reimplantation. However, hydronephrosis after RALUR-EV resolve more quickly at a median time of 7.9 months.