Ultrasonographic changes following pyeloplasty in children with ureteropelvic junction obstruction: a prospective observational before-after cohort study.

Background/objective: Ureteropelvic junction obstruction (UPJO) is a common congenital anomaly in pediatric patients. Although nuclear scintigraphy is traditionally considered the standard for postoperative follow-up, the associated radiation exposure, invasiveness, and cost have prompted interest in noninvasive options. This study evaluated postoperative ultrasonographic changes as a first-line surveillance tool for children undergoing pyeloplasty. Methods: This prospective observational before-after cohort study (March 2023-March 2024) evaluated 50 children (38 girls, 12 boys) treated for primary congenital UPJO. All underwent open pyeloplasty by two experienced surgeons, with Double-J stents removed at 4 weeks. Preoperative and 3-month postoperative evaluations compared sonographic parameters [anteroposterior pelvic diameter (APD), cortical thickness, renal length, hydronephrosis severity], diethylenetriamine pentaacetic acid renal scintigraphy, and biochemical markers. Surgical success was defined as clinical improvement alongside stable or improved sonography without the need for reintervention. Results: Postoperatively, significant reductions were observed in APD, hydronephrosis grade, serum creatinine, BUN, and random urine creatinine (all Conclusion: Ultrasonography is a safe, reliable, and practical first-line surveillance tool for post-pyeloplasty follow-up. Nuclear renography can be selectively reserved for patients showing clinical deterioration or a lack of sonographic improvement.