Regression of renal collecting system dilatation after pyeloplasty in children: evaluation of dynamics

Abstract

Introduction. Pediatric pyeloplasty ensures a successful outcome in 83 – 97% cases. However, current lack of consensus regarding the definition of "success" related to results of pyeloplasty prevents development of a generally accepted standardised approach to postoperative care management. Objective. To study the dynamics in regression of renal collecting system (RCS) dilatation in patients with urteropelvic junction obstruction (UPJO) following pyeloplasty. Materials & methods. We have investigated dynamics in regression of RCS dilatation in UPJO-patients following pyeloplasty. An intrinsic UPJO cause was established in 55 (80%) patients, an extrinsic factor (crossing vessel) — in 14 (20%) cases. The patients underwent surgery involving laparoscopic access, no reducing resection of the renal pelvis was performed. In the pre- and postoperative periods, renal ultrasonography was carried out in the prone position without volemic load and with an empty bladder. Pelvic anterior-posterior diameter measured in the sagittal plane were then compared. In all cases, external RCS drainage technique was employed until restoration of urodynamics in the upper urinary tract according to the pyelomanometry data.Results. In 3 months following pyeloplasty, a regression is noted in the RCS dilatation by 40%, after 6 months — by 53%, after 12 months –— by 64% of the initial value. In patients with intrinsic UPJO causes, after 3 months following pyeloplasty a regression is noted in the RCS dilatation by 34%, after 6 months –— by 42%, after 12 months — by 61% of the initial value; in patients with extrinsic PUJO factors, after 3 months the regression noted in RCS dilatation is 49%, after 6 months — 56%, after 12 months — 86%. Conclusion. Pre- and postoperative renal ultrasound in PUJO cases should be performed in the prone position without volemic load and with an empty bladder. In patients with confirmed restoration of UPJ patency after 12 months following surgery, a decrease in the RCS dilatation by 61% is noted among the patients with intrinsic PUJO causes and by 86% from pre-surgery values in children with extrinsic UPJO factors.

Keywords

• hydronephrosis
• ureteropelvic junction obstruction
• pyeloplasty
• anterior-posterior pelvic diameter
• ultrasound
• children
• review