Ultrasonographic changes following pyeloplasty in children with ureteropelvic junction obstruction: a prospective...

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.

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.

Postoperatively, significant reductions were observed in APD, hydronephrosis grade, serum creatinine, BUN, and random urine creatinine (all P < 0.001). Conversely, cortical thickness and renal length significantly increased bilaterally (all P < 0.001). Differential renal function was effectively preserved, with no significant postoperative changes (right: P = 0.209; left: P = 0.189). Additionally, patient age demonstrated significant positive correlations with multiple postoperative sonographic and biochemical parameters.

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.