ESPU Meeting on Friday 19, June 2026, 08:50 - 09:35
08:50 - 08:53
S20-1 (CP)
Phani AARE 1, Chandrasekharam VVS 1, Pawan SHINKAR 2 and Ramesh BABU 3
1) Ankura Hospitals for women and children, Paediatric Surgery, Paediatric Urology and Minimal Access Surgery, Hyderabad, INDIA - 2) Ankura Hospitals for women and children, Radiology, Hyderabad, INDIA - 3) SRIHER, Pediatric urology, Chennai, INDIA
PURPOSE
Most often posterior renal malrotation with Uretero Pelvic Junction Obstruction (UPJO) presents as an intraoperative surprise finding. A posteriorly oriented pelvis can make standard pyeloplasty technically challenging, increase operative time, predispose to recurrent obstruction or the need for ureterocalicostomy. MR urography (MRU) accurately defines renal rotation, but routine MRU is not cost effective and may need general anaesthesia. This study evaluated whether a simple, reproducible sonographic measurement—the intrarenal to extrarenal pelvis length ratio (PIER)—can predict posterior renal malrotation pre-operatively. We hypothesized that the renal pelvis in posterior malrotation has restricted space to enlarge extrarenally resulting in larger intrarenal pelvis
MATERIAL AND METHODS
This retrospective diagnostic study included 30 children with UPJO: 15 with intraoperatively confirmed posterior renal malrotation and 15 group-matched UPJO controls with normal kidney orientation. Intrarenal (IR) and extrarenal (ER) pelvis lengths were measured from standardized longitudinal ultrasound images by a radiologist blinded to rotation status. PIER was the primary variable; the intrarenal fraction [IR/(IR plus ER)], was analysed secondarily. Statistical analysis was performed using IBM SPSS Statistics v31. Group comparisons used the Mann-Whitney U test. Diagnostic performance was evaluated using receiver operating characteristic (ROC) analysis and Youden index to determine optimal cutoff thresholds.
RESULTS
Posteriorly malrotated kidneys demonstrated significantly larger intrarenal pelvis and smaller extrarenal portions compared with controls. PIER was substantially higher in the posterior malrotated group (median 1.45) compared with non-rotated kidneys (median 0.54). The difference was statistically significant (Mann-Whitney U equal to 25, Z equal to minus 3.63, p less than 0.001). Effect size analysis indicated a large discriminatory signal (Cliff's delta equal to 0.78; Cohen's d equal to 2.15). ROC analysis yielded an area under the curve (AUC) of 0.889, indicating good diagnostic accuracy. The optimal PIER cutoff for predicting posterior malrotation was 1.33, corresponding to a sensitivity of 86.7% and specificity of 86.7%. Similar performance was observed with the IR/(IR plus ER) fraction (AUC equal to 0.889).
CONCLUSIONS
The PIER measurement on routine ultrasound is a promising marker for detecting posterior renal malrotation in children with UPJO. We recommend that those with PIER greater than 1.33 may be considered for a preoperative MRU so that surgeon can be prepared to deal with a posterior malrotation. Further multicentre studies are needed to confirm these findings.
08:53 - 08:56
S20-2 (CP)
Ahmet Furkan OZSOY 1, Efe Semetey OGUZ 1, Altay AK 1, Omer Suat FITOZ 2, Berk BURGU 3 and Yakup Tarkan SOYGUR 3
1) ANKARA UNIVERSITY SCHOOL OF MEDICINE, UROLOGY, Ankara, TÜRKIYE - 2) ANKARA UNIVERSITY SCHOOL OF MEDICINE, PEDIATRIC RADIOLOGY, Ankara, TÜRKIYE - 3) ANKARA UNIVERSITY SCHOOL OF MEDICINE, PEDIATRIC UROLOGY, Ankara, TÜRKIYE
PURPOSE
This study aimed to evaluate the predictive value of pyramidal thickness—an ultrasonographic parameter that has recently gained increasing attention for its more objective measurement compared to other sonographic indices—and associated factors in determining the indication for pyeloplasty. Additionally, we sought to assess postoperative changes in pyramidal thickness.
MATERIAL AND METHODS
Between September 2024 and September 2025, 36 pediatric patients who underwent pyeloplasty and 40 pediatric patients who were managed conservatively after presenting to our clinic with a preliminary diagnosis of ureteropelvic junction obstruction were prospectively evaluated. Pre-treatment ultrasonographic parameters, including pyramidal thickness, findings from diuretic renal scintigraphy, and ultrasonographic follow-ups at 3 and 6 months post-treatment were analyzed. The predictive power of pyramidal thickness and its associated factors in determining the need for pyeloplasty was examined using receiver operating characteristic (ROC) curve analysis.
RESULTS
The median ipsilateral pyramidal thickness was 2.1 mm [IQR: 1.7–3.0] in the pyeloplasty group and 3.15 mm [IQR: 2.9–3.4] in the observation group (p<0.001). The median ipsilateral-to-contralateral pyramidal thickness ratio was 0.48 [IQR: 0.28–0.55] in the pyeloplasty group and 0.61 [IQR: 0.54–0.72] in the observation group (p<0.001). In multivariate logistic regression analysis, factors independently associated with the decision for pyeloplasty included reduced parenchymal thickness (OR: 0.18; 95% CI: 0.03–0.88; p=0.034), decreased pyramidal thickness (OR: 0.005; 95% CI: 0.00–0.11; p<0.001), and increased anteroposterior diameter (OR: 1.41; 95% CI: 1.06–1.89; p=0.018). The area under the curve (AUC) for the developed pyeloplasty risk score based on these parameters was 0.915. At a cutoff value of 80 points, the sensitivity and specificity were 88.9% and 85%, respectively, independent of renal function. Post-treatment evaluations revealed a significant increase in renal pyramidal thickness and related parameters in the pyeloplasty group compared with the observation group. The total follow-up duration was similar between the groups, with a median of 250 days (194–346) in the pyeloplasty group and 240 days (200–300) in the observation group (p = 0.595).
| Parameters, Median (IQR 25-75) | Pıyeloplasty | Observation | p value |
| Pyramidal thickness on diagnostic USG, mm | 2.1 (1.7 - 3) | 3.15 (2.9 - 3.4) | < 0.001 |
| Pyramidal thickness on third month USG, mm | 3.15 (2.67 - 3.7) | 3.4 (3.2 - 3.72) | 0.150 |
| Pyramidal thickness on sixth month USG, mm | 3.8 (3.37 - 4.32) | 3.7 (3.5 - 4) | 0.399 |
| Total follow-up time, days | 250 | 240 | 0.595 |
CONCLUSIONS
Pyramidal thickness and its associated ultrasonographic parameters were significantly reduced in patients undergoing pyeloplasty compared to those managed conservatively. These parameters demonstrated a high predictive value in determining the need for pyeloplasty.
08:56 - 08:59
S20-3 (CP)
Kenneth SOFTNESS 1, George SIDERIS 2, Tanya LOGVINENKO 1, Michael KURTZ 1, Neha KWATRA 2, Jeanne CHOW 2 and Caleb NELSON 1
1) Boston Children's Hospital, Department of Urology, Boston, USA - 2) Boston Children's Hospital, Department of Radiology, Boston, USA
PURPOSE
Renal ultrasonography and nuclear scintigraphy are two important tests for upper tract urinary obstruction in newborns. While the Urinary Tract Dilation (UTD) system explicitly specifies utilizing the intrarenal anterior-pelvic diameter (APRPD), it is not understood the predictive value of the intra- versus extrarenal pelvis to predict obstruction on a subsequent nuclear study. We aimed to use a large retrospective series of newborns to compare the predictive ability of the intra- versus extrarenal pelvis on drainage parameters of subsequent MAG3 study.
MATERIAL AND METHODS
Ultrasound measurements on 494 patients were made by two reviewers to measure intra- and extrarenal APRPD and all other UTD parameters, and outcomes were collected, including MAG3 where obtained. We performed linear and logistic regression (with two different cutoffs) to assess the impact of intra- and extrarenal APRPD on drainage half-times while controlling for bladder distention on ultrasound. AUC’s and accuracies were calculated with 5-fold cross validation and directly compared using DeLong’s and McNemar’s tests, respectively.
RESULTS
84/494 patients ultimately underwent MAG3 (Mean +/- SD intra- and extrarenal APD 1.52 +/- 0.80 mm and 1.69 +/-0.94 mm, respectively). Comparing the predictive value of intra- versus extrarenal APRPD on MAG3 parameters, the adjusted R2 was higher and the AIC lower for extrarenal pelves predicting obstruction across all six models, indicating the models using extrarenal diameter better fit the data. In terms of accuracy, extrarenal APRPD achieved higher AUC in predicting t1/2>20 and and t1/2 >10 min, with the exception of one model. However, comparing AUC’s using DeLong test and accuracies using McNemar’s test did not reach statistical significance. (Figure 1)
|
Figure 1 |
||||
|
Outcome |
Metric |
Intrarenal |
Extrarenal |
Better? |
|
log (t½) |
Adjusted R2 (L/R) |
0.12 / 0.32 |
0.20 /0.38 |
Extrarenal |
|
AIC (L/R) |
202 / 156 |
196 / 151 |
||
|
t½> 10 min |
AUC (L/R) |
0.77 / 0.83 |
0.83/ 0.83 |
Equivocal |
|
Accuracy (L/R) |
0.85 / 0.76 |
0.82 / 0.72 |
||
|
t½> 20 min |
AUC (L/R) |
0.62 / 0.84 |
0.72 / 0.86 |
Extrarenal |
|
Accuracy (L/R) |
0.70 /0.75 |
0.67 /0.77 |
||
CONCLUSIONS
The predictive power appears to be slightly better for extrarenal versus intrarenal APRPD although not statistically significant. While this confirms that renal pelvic dilation on ultrasound is highly predictive of obstructive drainage parameters, the exact site of measurement is likely not of major clinical importance.
09:11 - 09:14
S20-4 (CP)
Saidanvar AGZAMKHODJAEV 1, Vitaly DUBROV 2, Vladimir SIZONOV 3, Sergey BONDARENKO 4, Zafar ABDULLAEV 1, Ergashev KOBILJON 1, Dmitriy CHOKLYA 5, Kiril PELIKH 6, Dmitriy FILIPPOV 6, Nikita ROTKO 2, Ekaterina KONDRATYEVA 7 and Ilia KAGANTSOV 7
1) NATIONAL CHILDREN'S MEDICAL CENTER, DEPARTMENT OF PEDIATRIC UROLOGY, Tashkent, UZBEKISTAN - 2) Children's City Clinical Hospital № 2, PEDIATRIC UROLOGY, Minsk, BELARUS - 3) Rostov Regional State Budgetary Institution "Regional Children's Clinical Hospital", PEDIATRIC SURGERY, Rostov-On-Don, RUSSIAN FEDERATION - 4) State Healthcare Institution "Emergency Clinical Hospital № 7", PEDIATRIC SURGERY, Volgograd, RUSSIAN FEDERATION - 5) State Institution "Republican Children's Clinical Hospital", PEDIATRIC SURGERY, Syktyvkar, RUSSIAN FEDERATION - 6) State Budgetary Healthcare Institution Children's City Hospital № 22, PEDIATRIC SURGERY, St.Petersburg, RUSSIAN FEDERATION - 7) Almazov National Medical Research Center, PEDIATRIC SURGERY, St.Petersburg, RUSSIAN FEDERATION
PURPOSE
An obstruction of the ureteropelvic junction in a horseshoe kidney represents a rare condition in pediatric and adult populations. Several small-cohort studies have reported the efficacy of pyeloplasty in children with horseshoe kidneys, but only a limited number have compared different surgical techniques. To assess the long-term surgical outcomes of different approaches for horseshoe kidney in children.
MATERIAL AND METHODS
We conducted a retrospective multicentric analysis of 112 pyeloplasties performed on 105 children from 1999 to 2024. The patients were stratified into three groups based on the type of surgical intervention received: open pyeloplasty with isthmotomy, open pyeloplasty without isthmotomy, and laparoscopic pyeloplasty. Additionally, we categorized the patients into four groups according to the method of urinary tract drainage (internal DJ stent; nephrostomy; pyeloplasty catheter; drainless pyeloplasty).
RESULTS
Favorable outcomes were achieved in 92.9% of patients who underwent pyeloplasty. No significant differences in results were observed among the surgical groups (p=0.024). We also found no statistically significant differences between the various methods of urinary tract drainage (p=0.0036).
CONCLUSIONS
Preference should be given to minimally invasive treatment modalities without the need for isthmotomy, even for complex developmental anomalies such as hydronephrotic transformation of a horseshoe kidney.
09:14 - 09:17
S20-5 (CP)
Sami CHERIGUI 1, Santiago VALLASCIANI 2, Mohammed ELIFRANJI 3, Ibrahim Adnan KHALIL 4, Muthana AL SALIHI 3, Tariq ABBAS 3, Abderrahman ELKADHI 3, Noor ALKHORI 5, Eman AJLAN 5 and Joao Luiz PIPPI SALLE 6
1) Hamad Medical Corporation, Pediatric Surgery, Doha, QATAR - 2) Sidra Medical and Research Center, Pediatric Urology Division, Doha, QATAR - 3) Sidra Medicine, Pediatric Urology, Doha, QATAR - 4) Hamad Medical Corporation, Urology, Doha, QATAR - 5) Sidra Medicine, Pediatric Radiology, Doha, QATAR - 6) Sickkids Hospital, Pediatric Urology, Toronto, CANADA
PURPOSE
Contralateral hydronephrosis (CLHN) is observed in some patients with unilateral Ureteropelvic Junction Obstruction (UPJO). We hypothesize that concurrent CLHN associated with UPJO is associated with increased diuresis in the normal kidney; therefore, it should improve after successful pyeloplasty.
MATERIAL AND METHODS
Retrospective review of the images of ultrasounds of patients with unilateral UPJO and concurrent CLHN who underwent successful pyeloplasty done by an independent radiologist. CLHN was defined as an anterior-posterior renal pelvic diameter (APRD) ≥7 mm and a Society for Fetal Urology (SFU) score≥1 on preoperative ultrasound (US) with a normal MAG3 renogram. Assessment was done in 3 time periods: preoperative (T0: 1-32 weeks before surgery), early postoperative (T1: 4-26 weeks after surgery) and late postoperative (T2: 27-104 weeks after surgery). Four US parameters were reviewed: APRD, SFU grade, cortical thickness and kidney volume. Statistical analysis of the data was done using the Friedman Chi-square test, the Wilcoxon test, and the Bonferroni correction.
RESULTS
CLHN was present in 32 of the 183 cases of unilateral UPJO who underwent pyeloplasty (17.5%). Twenty-eight patients had adequate postoperative follow-up. Mean age at surgery was 24 months (range: 1-152 months): significant reduction of CLHN was observed in 26/28 (92%) patients with successful pyeloplasty between T0 and T2: the median APRD decreased from 10 to 7 mm (p=0.000301, p.adj=0.000903) and SFU grade decreased from 2 to 1 (p=0.000264, p.adj=0.000792). Persistence of CLHN occurred in 2 patients with impaired renal function (less than 30%), which did not improve despite successful pyeloplasty.
CONCLUSIONS
CLHN improves in most patients after successful pyeloplasty, except when preoperative renal function is severely impaired. Improvement occurs regardless of pyeloplasty timing or patient age, so it is unlikely to reflect spontaneous resolution of low-grade hydronephrosis as seen in early childhood. Postoperative evolution of CLHN may help assess outcomes after pyeloplasty and serve as a valuable indicator of surgical success.
09:17 - 09:20
S20-6 (CP)
Jose Luis GONZALEZ 1, Elias RAMIREZ 1, Mario DIAZ 1, Fernando GONZALEZ 1, Sofia BRENES 2 and Andres MENJIVAR 1
1) HOSPITAL INFANTIL DE MEXICO FEDERICO GOMEZ, UROLOGIA PEDIATRICA, Cuauhtemoc, MEXICO - 2) HOSPITAL GENERAL REGIONAL NO 1 UNIDAD MORELOS DEL INSTITUTO MEXICANO DEL SEGURO SOCIAL, CIRUGIA PEDIATRICA, Chihuahua, MEXICO
INTRODUCTION
Dismembered pyeloplasty (DP) is currently the preferred treatment for ureteropelvic junction obstruction (UPJO). It has a high success rate; however, managing recurrence is challenging. The aim of this study is to assess the risk factors related to the recurrence of Ureteropelvic Junction Obstruction (RUPJO) in pediatric patients post-DP.
MATERIAL AND METHODS
A retrospective cohort study was conducted on consecutive patients undergoing dismembered pyeloplasty at a tertiary referral center between January 2019 and January 2024. Exclusion criteria included redo surgeries, renal exclusion, and incomplete records. Variables analyzed included age, surgical approach (laparoscopic, open anterior, oblique, or posterior), stent type, trainee involvement in critical steps, and anteroposterior diameter (APD) of the pelvis. Diagnosis of RUPJO was confirmed via ultrasound and MAG 3 renogram. Univariate, bivariate, and multivariate binary logistic regression analyses were performed to identify risk associations. Statistical significance was defined as a p value less than 0.05.
RESULTS
The study included 97 patients representing 110 renal units. The majority were male (83.5 percent) with a mean age of 47.9 months. Multivariate analysis identified a strong correlation between preoperative APD exceeding 25 mm (determined via ROC curve analysis) and post-surgical stenosis (p equals 0.011; OR 4.78). The posterior surgical approach was significantly associated with recurrence (46.7 percent; p less than 0.001), specifically in patients with APD greater than 25 mm. Notably, resident involvement in critical surgical steps was identified as a significant independent risk factor (OR 4.8; p equals 0.001). When excluding cases with significant trainee involvement, APD greater than 25 mm remained a significant risk factor (p equals 0.032). While trans-anastomotic drains and tubeless techniques showed protective trends in bivariate analysis, they lacked significance in multivariate models.
CONCLUSIONS
An APD greater than 25 mm, the posterior surgical approach, and significant resident involvement are independent risk factors for RUPJO. The high recurrence rate observed with the posterior approach and trainee involvement emphasizes the importance of surgical technique and supervision, particularly in training hospitals. These findings suggest that patients with an APD exceeding 25 mm require meticulous surgical planning.