Ultrasound Monitoring after Pelvis-Sparing Dismembered Pyeloplasty: High Sensitivity and Low Specificity for the Success of Operation

Study of 73 pediatric patients demonstrates that decreased renal pelvis diameter on ultrasound after pelvis-sparing pyeloplasty reliably indicates successful drainage (100% PPV), while increased diameter has low predictive value for obstruction (42% NPV). Findings suggest renal scans may only be necessary when postoperative ultrasound shows increased anteroposterior diameter.