Endoscopic Balloon Dilatation as a Diagnostic and Therapeutic Tool for Primary Obstructive Megaureter. 10 Year Experience.

Purpose: To describe our 10-year experience with EBD for primary obstructive megaureter. Materials and Methods: Children needing intervention for primary obstructing megaureters (POM) (based on increasing distal dilatation >1.4 cm, differential renal function [DRF] <40%, or symptoms) were counseled to undergo a trial of EBD. A 9.5Fr cystoscope and stent "pusher" were used to insert a 14'' guidewire to allow insertion of a 4/25 mm coronary dilatation balloon that was insufflated to 15 ATM for 5 minutes. Afterwards a 4.7Fr Double-J stent was positioned for 6 weeks. Ureteral diameter, DRF, length of obstruction, and complications were registered. Success was defined as improvement of the indication without further need for a more invasive procedure. Results: A total of 31 dilated ureters in 28 patients (23/5 M/F) were included, with a median age of 9 months (M) (range: 1-111) and a follow-up of 41 M (range: 12-84). EBD showed a narrow ring in 29 (93.5%) and longer narrow distal ureters in 2 (6%). EBD was successful in 29/31 ureters (93.5%), with different success rates for a narrow ring (96.6%) and a longer narrow distal ureter (50%). Conclusion: As most POM resolve spontaneously, hard indications are needed before treatment is offered. Symptomatic patients (e.g., infections) and declining DRF with dilated ureters are strong indications. In such cases, EBD with a coronary dilatation balloon has a high success rate and provides diagnostic information regarding the length of the narrow ureteral segment. Longer narrow ureteral segments are rare but result in a higher failure rate.