[Balloon dilation treatment of primary obstructive megaureter in children]

Investigation of the results of ureteral stricture single balloon dilation in children with primary obstructive megaureter.

Since 2012 to 2020 79 children (65 boys and 15 girls) with primary obstructive megaureter of II and III grades who had 92 affected ureters were operated on by method of ureteral stricture balloon dilation. Duration of postoperative stenting period was Me=68 [48; 91] days, bladder catheterization period - Me=15 [5; 61] days. Follow-up was from 1 to 10 years.

There were no intraoperative complications in the group of investigation. Pyelonephritis exacerbation in the early postoperative period occurred in 15 cases (18,98%). Control comprehensive examination revealed that urodynamics of 63 children (79,74%) tended to normalization what persisted in the future. There was no positive dynamics in 16 cases (20,25%). Vesico-ureteral reflux was revealed in 4 cases.

Assessment of impact of various predictors (passport, urodynamic, infectious, anatomic, operation and postoperative period characteristics) on the treatment results proved that the effectiveness of the procedure depends on the following factors: ureteral stricture length (M-U Test U=202,5 p=0,0002) and features of the stricture rapture during ballooning (Fisher exact p=0,0006). There was significant difference in results in the group of up to 10 mm inclusive stricture length and the longer stricture group (Fisher exact p=0,00001). High activity of pyelonephritis in postoperative period was the predictor of adverse outcome (Fisher exact p=0,00001).

Practically 80% of children with primary obstructive megaureter may be reliably cured by the method of ureteral stricture balloon dilation. The risk of intervention failure is greatly increased in case of the stricture length is more than 10 mm and technical difficulties of ballooning indicating a high resistance of the narrowed portion of the ureter to dilation.