E-Mail karger@karger.com Original Paper Urol Int 2014;93:406–410 DOI: 10.1159/000362504 Can Renal Ultrasonography Predict Early Success after Pyeloplasty in Children? A Prospective Study Tamer E. Helmy a Ahmed Harraz a Doaa E. Sharaf b Yasser El Demerdash a Ashraf T. Hafez a Hossam Gad b Mohammed Dawaba a Departments of a Urology and b Radiology, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt change was the largest unique contribution for explaining the variance in parenchymal growth, followed by antero- posterior diameter and calyceal dilatation. Conclusion: We proved that calyx-to-parenchyma ratio, anteroposterior di- ameter and calyceal dilatation are independent predictors of early success after pyeloplasty. © 2014 S. Karger AG, Basel Introduction Ureteropelvic junction obstruction is a common prob- lem encountered by urologists [1]. The decision for sur- gical intervention is usually based on the decrease in dif- ferential renal function (DRF) on diuretic renogram and worsening of hydronephrosis on ultrasonography (USG) findings. Dismembered pyeloplasty has a high success rate in most reported series [2, 3]. The main reason for follow- ing patients after pyeloplasty is the early detection of chil- dren who will, unfortunately, experience recurrent ob- struction and may require further interventions to avoid additional loss in renal function. Considering the fact that pyeloplasty is a successful procedure, the majority of chil- dren will have a favorable outcome. Postoperative evalua- tion protocols are being established to detect the small number of patients who experience an unwanted deterio- Key Words Pyeloplasty · Differential renal function · Cortical thickness · Ultrasound Abstract Objective: To study the predictive value of 6 ultrasonograph- ic (USG) parameters for early detection of children at risk of recurrent obstruction. Patients and Methods: A prospective nonrandomized study included all patients who underwent pyeloplasty between 2010 and 2012. All of the patients had completed at least 6 months of follow-up and preoperative and postoperative USG imaging data were available. The pri- mary outcome was the correlation between USG and diuret- ic scintigraphic parameters. The secondary outcome was the predictive ability of the pelvicalyceal system parameters, measured by USG, of parenchymal growth after surgery. Re- sults: Sixty-eight patients were evaluated. The mean age was 3.6 years (range 0.1–12). The mean (± standard deviation) dif- ferential renal function improved from 37.4 ± 11 ml/min to 37.7 ± 14 ml/min, which was a difference of no statistical sig- nificance. On the other hand, the mean (± SD) half-time (T 1/2 ) significantly improved. After constructing a linear regression model of the 4 USG parameters and the parenchymal growth, the model explained 57.2% of the variance in parenchymal growth after pyeloplasty. The calyx-to-parenchyma ratio Received: December 12, 2013 Accepted after revision: March 26, 2014 Published online: August 13, 2014 Internationalis Urologia Tamer E. Helmy, MD Urology and Nephrology Center, Mansoura University 18 El Gomhoria Street Mansoura 35516 (Egypt) E-Mail drthelmy  @  yahoo.com © 2014 S. Karger AG, Basel 0042–1138/14/0934–0406$39.50/0 www.karger.com/uin