503 The ultrasonographic evolution of the hydronephrosis and renal parenchyma thickness in patients with congenital ureteropelvic junction (UPJ) obstruction who underwent pyeloplasty

Abstract

Listen

Translate article

INTRODUCTION AND OBJECTIVES: Introduction: Pyeloplasty is an established treatment for pelviureteric junction (UPJ) obstruction. After pyeloplasty diuretic renograms are often obtained to document surgical success by demonstrating better urinary drainage. However, while diuretic renograms may be the most accurate way to evaluate surgical outcome in the early postoperative period, renal ultrasound is more commonly used for long-term followup because it is less invasive and more cost-effective. OBJECTIVE: The aim of this study was to determine the ultrasonographic evolution of the pelvic and caliceal dilatations and of the renal parenchyma thickness in patients with congenital hydronephrosis who underwent pyeloplasty. METHODS: Materials and Methods: From January 2006 to January 2010, 265 patients with prenatally diagnosed hydronephrosis underwent a protocol of antibiotic prophylaxis, ultrasound, diuretic renography(DTPA) and voiding cystourethrography. Of the 265 patients, 85 (32%) who showed a trend of progressive hydronephrosis underwent pyeloplasty and were included. All the patients were evaluated with DTPA scans on the sixth month after surgery. The ultrasound performed before the surgery as well as all performed in the first 3,6,12,24 and 36 months after the pyeloplasty were reviewed and compared. The trends in the changes in these studies were studied. Statistical analyses were performed with SPSS (Statistical Package for the Social Sciences) version 18.0. RESULTS: All patients significantly improved the renal washout time (T1⁄2) in DTPA scans at six months postoperatively. The rate of caliceal dilatation decrease in the first 3, 6 and 12 months after surgery were 60%, 91,7%, and 100%, respectively. In a follow-up period of at least 1 year, 43 (50,6%) renal units had complete resolution of the pelvic dilation and 72 (84.7%) of the caliceal dilatation. The renal parenchyma was normal or had increased in 76 (89,4 %) of cases. CONCLUSIONS: The decrease in pelvic and caliceal dilatations occurred in the majority of the patients, but its complete resolution is relatively slow. Serial ultrasound is noninvasive and could replace serial invasive renal scans decreasing costs, instrumentation, and radiation exposure.