Predictors of Renal Functional Improvement After Pyeloplasty in Ureteropelvic Junction Obstruction: Clinical Value of Visually Assessed Renal Tissue Tracer Transit in 99m Tc-mercaptoacetyltriglycine Renography

摘要

Objective To determine the clinical value of visually assessed renal tissue transit time (TTT) in 99m Tc-mercaptoacetyltriglycine ( 99m Tc-MAG3) renography for patients undergoing pyeloplasty. Materials and Methods Medical records of 164 patients who underwent dismembered pyeloplasty were retrospectively reviewed. Baseline and postoperative renal ultrasonography and 99m Tc-MAG3 renography were performed. Two urologists blinded to clinical data evaluated the renography and classified TTT as timely or delayed based on visualization of the tracer in the kidney pelvis between 2 and 10 minutes. Renal functional change after pyeloplasty was compared between patients in the timely and delayed groups. Results A total of 126 patients (median age, 9 months) were evaluated after excluding patients with bilateral ureteropelvic junction obstruction, a single functioning kidney, duplicated ureter, or 5% improvement in renal function after pyeloplasty. Conclusion Delayed TTT in 99m Tc-MAG3 renography was a significant predictor of renal functional improvement after pyeloplasty in ureteropelvic junction obstruction. Because substantial improvement of renal function is anticipated, we recommend immediate pyeloplasty in patients with delayed TTT and decreased DRF.