Can Distal Ureteral Diameter Predict Reflux Resolution After Endoscopic Injection?

Predictors of reflux persistence after endoscopic dextranomer/hyaluronic Acid copolymer injection in pediatric patients with Vesicoureteral reflux: short-term results

This study aims to investigate the factors effective in predicting the persistence of reflux after the first subureteric transurethral injection (STING) of dextranomer/hyaluronic acid copolymer in pediatric patients with vesicoureteral reflux. The data of patients without a previous history of surgery to treat vesicoureteral reflux and who underwent STING for the first time between September 2011 and November 2020 were investigated retrospectively. After considering exclusion criteria, of 199 patients, 127 patients and 180 renal units were suitable for inclusion. A renal unit-based evaluation was made. Age < 61 months (univariate: p = 0.001, multivariate: p = 0.015, HR: 2.352 (1.181-4.686), OR (95% CI)), moderate reflux level (grade 3) (univariate: p < 0.001, multivariate: p = 0.019, HR: 2.703 (1.177-6.209), OR (95% CI)), DRF (differential renal function) < 45 (univariate: p = 0.020, multivariate: p = 0.047, HR: 1.992 (1.009-3.935), OR (95% CI)), and UDR (ureteral diameter ratio) > 0.15 (univariate: p < 0.001, multivariate: p = 0.005, HR: 2.786 (1.368-5.672), OR (95% CI)) were found predictors of reflux persistence after STING surgery both univariate and multivariate analysis. High reflux level (grade 4-5) was statistically significant in univariate analysis (p < 0.001) but not statistically significant in multivariate analysis (p = 0.215). In our study, UDR and DRF were found to be factors affecting reflux persistence. UDR and DRF should be considered in order to predict reflux resolution in patients who will undergo STING.

An evaluation of ureteral diameter ratio and vesicoureteral reflux index in the treatment of primary vesicoureteral reflux

Objective

Vesicoureteral reflux (VUR) index is a simple, validated tool that reliably predicts significant improvement and spontaneous resolution of primary reflux in children. The aim of this study was to evaluate and compare the ureter diameter ratio (UDR) and VUR index (VURx) of patients treated with endoscopic injection (EI) and ureteroneocystostomy (UNC) methods in the pediatric age group due to primary VUR.

Methods

Patients under the age of 18 years old who underwent EI and UNC with the diagnosis of primary VUR between January 2011 and September 2021 were determined as the participants. The UDR was assessed using voiding cystourethrography, and the VURx score was determined prior to treatment based on hospital records included in the study.

Results

A total of 255 patients, 60 (23.5%) boys and 195 (76.5%) girls, with a mean age of 76.5 (range 13.0-204.0) months, were included in the study. EI was applied to 130 (51.0%) patients and UNC was applied to 125 (49.0%) patients due to primary VUR. The optimum cut-off for the distal UDR was obtained as 0.17 with sensitivity and specificity of 73.0% and 63.0%, respectively. The positive and negative predictive values were 66.0% and 70.0%, respectively.

Conclusion

When the UDR and VURx score are evaluated together for the surgical treatment of primary VUR in the pediatric age group, it is thought that it may be useful in predicting the clinical course of the disease and evaluating surgical treatment options.

Ultrasound-based predictive indicators for treatment outcomes in pediatric vesicoureteral reflux

PURPOSE

To evaluate the effectiveness of preoperative ultrasound (US) measurements in predicting pediatric vesicoureteral reflux (VUR) treatment outcomes.

METHODS

This prospective study enrolled 35 patients (53 renal units) aged 1-16 years who underwent subureteric injection therapy for primary VUR between July 2020 and June 2022. Preoperative ultrasound examinations measured the bladder wall thickness at the ureteral orifice, ureteral submucosal tunnel length, distal ureteral diameter, patient demographics, VUR grade, presenting complaints, bladder-bowel dysfunction, and renal scarring, and the impact of these variables on treatment success was analyzed.

RESULTS

Among the patients, 91.4% were female, with a mean age of 6.83 ± 3.84 years. A comparison between the treatment success and failure groups revealed no significant differences in the age, sex, VUR grade, laterality, bilaterality, presenting complaints, bladder-bowel dysfunction, bladder wall thickness, or distal ureteral diameter (p > 0.05). However, renal scarring occurred in 16 (38.1%) patients in the treatment success group and 10 (90.9%) in the treatment failure group (p = 0.002). The treatment failure group had shorter detrusor-to-ureteral orifice distances and smaller detrusor-ureteral orifice distance-to-distal ureteral diameter (D/U) ratios than that of the success group (p = 0.004 and p = 0.006, respectively). Patients with a detrusor-to-ureteral orifice distance < 7.4 mm had an 81.82% likelihood of treatment failure.

CONCLUSION

Ultrasound measurements of the detrusor-to-ureteral orifice distance and D/U ratio proved reliable in predicting the success of endoscopic subureteric injection therapy for VUR.

Does the distal ureteral diameter ratio (UDR) matter in the surgical management of vesicoureteral reflux in children?

PURPOSE

To evaluate UDR reliability, sensitivity, specificity and to identify the best treatment basing on UDR among single or double endoscopic injections and ureteral reimplantation.

METHODS

Data of patients affected by primary VUR and treated by endoscopic injection over a 10 years period were retrospectively analyzed. Two radiologist attributed reflux grade and UDR on voiding cystourethrogram twice and blinded. Follow-up focused on resolution after 1 or 2 endoscopic injections. Relation between UDR, reflux grade and outcomes were analyzed.

RESULTS

Patient enrolled were 198. Low grade VUR was present in 24.8%, grade 3 in 41.6%, grade 4-5 in 33.6%. Resolution after one injection was obtained in 88 patients; among 110 not resolved 104 cases had a second injection. Success after 2 injections was reported in 138 cases. UDR showed a higher reliability compared with reflux grade both in intra than inter-reader measurement (ICC > 90%). Success after 1 or 2 injections was reported for UDR < 0.33 and UDR < 0.47 respectively.

CONCLUSION

UDR shows to be a more reliable measurement that allows for an objective estimation of VUR severity and prognosis. It represents a quantitative parameter that might be useful to identify patients who may benefit endoscopic or surgical treatment, avoiding unnecessary under or over-treatment.

The ureteral diameter ratio as a predictive factor in renal scarring associated with primary vesicoureteral reflux

INTRODUCTION

The ureteral diameter ratio (UDR) is reported to be effective in predicting the outcomes of vesicoureteral reflux (VUR) in several studies.

OBJECTIVE

The objective of the current study was to compare the risk of scarring in patients with VUR relative to UDR and the VUR grade. We also aimed to demonstrate other associated risk factors in scarring and investigate the long-term complications of VUR and their relationship with UDR.

STUDY DESIGN

Patients diagnosed with primary VUR were retrospectively enrolled in the study. UDR was calculated by dividing the largest ureteral diameter (UD) by the distance between L1-L3 vertebral bodies. Demographic and clinical data, laterality, VUR grade, UDR, delayed upper tract drainage on voiding cystourethrogram, recurrent urinary tract infections (UTI), and long-term complications of VUR were compared between the patients with and without renal scars.

RESULTS

A total of 127 patients and 177 renal units were included in the study. There was a significant difference between the patients with and without renal scars according to age at diagnosis, bilaterality, reflux grade, UDR, recurrent UTI, bladder bowel dysfunction, hypertension, decreased estimated glomerular filtration rate, and proteinuria. The logistic regression analysis revealed that UDR had the highest odds ratio among the factors affecting scarring in VUR.

DISCUSSION

VUR grading based on the evaluation of the upper urinary tract is one of the most important predictors for treatment options and prognosis. However, it is more likely to reflect ureterovesical junctional anatomy and function, which play a crucial role in the pathogenesis of VUR.

CONCLUSION

UDR measurement seems to be an objective method that can help clinicians predict renal scarring in patients with primary VUR.

Additional VCUG-related parameters for predicting the success of endoscopic injection in children with primary vesicoureteral reflux

INTRODUCTION AND OBJECTIVE

Prediction of vesicoureteral reflux (VUR) prognosis and decision for treatment are usually made according to the reflux grading classification. But the management of VUR is still controversial since there are difficulties in distinguishing reflux grade due to inter- and intra-observer variations. Previous studies have demonstrated that the distal ureteral diameter ratio (UDR) on voiding cystourethrography (VCUG) may be more predictive for clinical prognosis than reflux grade. We aimed to predict the success of endoscopic injection in primary VUR by creating new models that include other additional parameters (timing of reflux, delayed post-voiding contrast drainage of the upper urinary tract) as well as UDR.

STUDY DESIGN

A total of 200 patients aged 2-15 years with primary VUR undergoing endoscopic injection were retrospectively evaluated. Demographic and clinical data for a total of 248 renal units were recorded. Besides reflux grade and laterality, distal ureteral diameter, UDR, timing of reflux [early filling, late filling or voiding] and presence of contrast delay in upper tract drainage were also assessed on VCUG. According to the complete resolution of VUR on the control VCUG at the postoperative 3rd month, the renal units were divided into two main groups: successful (n = 171, 68.9%) and unresolved (n = 77, 31.1%) RESULTS: The failure rate of endoscopic injection was found to be 4.068 times greater with early filling reflux on VCUG, 3.076 times greater with UDR>0.24, 2.745 times greater with delayed contrast drainage of the upper urinary tract, 2.666 times greater with the presence of scar in DMSA, 2.493 times greater with bladder-bowel dysfunction and 2.341 times greater with febrile urinary tract infection. We also observed that a model in which all VCUG-related parameters were combined provided a better estimation of endoscopic injection outcomes compared to only the reflux grade (AUC: 0.903 vs. 0.604, respectively).

DISCUSSION

Distal ureteral dilatation is considered to be a more decisive factor for clinical outcomes of primary VUR rather than upper urinary tract dilatation since ureterovesical junction anatomy plays a more important role in primary VUR pathophysiology. Studies investigating new prediction models on this topic have recently become more popular. However, a consensus has not yet been achieved.

CONCLUSION

We consider that UDR level, the timing of reflux and delayed upper tract drainage on VCUG may be more predictive parameters of endoscopic injection success compared with reflux grade, and could facilitate selecting the best candidates for surgery.

Endoscopic Injection Treatment of Vesicoureteral Reflux in Children: Meeting with the Factors Involved in the Success Rate

The challenges and controversies in vesicoureteral reflux intervention guidelines resulted in a more individualized treatment planning. Endoscopic injection therapy is now widely used and is considered preferable, but still remains less successful than ureteral reimplantation. Τhe endoscopic vesicoureteral reflux approach should be risk-adapted to current knowledge, so more experience and longer-term follow-up are needed. The precise of preoperative, intraoperative, and postoperative factors that affecting endoscopic injection therapy success rates and outcome have not yet been clearly determined. The aim of this study was to investigate these associated factors. Although the reflux grade is the most well-known factor that can affect the success of the procedure, there is no agreement on which factors are the most influential for the efficacy of endoscopic reflux treatment. So, we carried out a broad review of published papers on this topic, and we presented all the potential predictive variables of endoscopic reflux resolution in children.

Can distal ureteral diameter measurement predict primary vesicoureteral reflux clinical outcome and success of endoscopic injection?

OBJECTIVE

The objective of the study was to evaluate the predictive value of distal ureteral diameter ratio (UDR) on outcome of primary vesicoureteral reflux (VUR) and reflux resolution after endoscopic injection.

PATIENTS AND METHODS

Three hundred eighty-three patients treated for primary VUR between January 2010 and October 2015 were retrospectively reviewed. The parameters analyzed were age at diagnosis, sex, grade and lateralite of VUR, complaints at admission (febrile urinary tract infection, antenatal hydronephrosis, family history),bladder-bowel dysfunction (urgency, incontinence, constipation), dimercaptosuccinic acid (DMSA) scintigraphy findings, follow-up period, clinical course (spontaneous resolution or surgical correction), time of spontaneous resolution, surgical treatment time and age, materials used for injection and success of endoscopic injection. Ureteral diameter ratio was calculated on the initial VCUG at the time of the diagnosis as the largest ureteral diameter within the false pelvis divided by the distance between L1-L3.The correlation between UDR, clinical outcome (spontaneous resolution/surgical correction) and success of endoscopic injection was evaluated by logistic regression analysis. To compare the effect of UDR and grade of reflux on spontaneous resolution, multivariate logistic regression analysis was performed in three models together with sex, age, resolution time, presence of febrile UTI and DMSA scan findings.

RESULTS

Three hundred eighty-three patients were enrolled. There was a strong correlation between UDR and grade of reflux (p < 0,0001). Ureteral diameter ratio was higher in patients whose complaints at admission were family history and febrile UTI, but this correlation was not statistically significant (p > 0.05). When the correlation between UDR and the DMSA scan findings was evaluated, UDR was found to be significantly higher in patients with moderate and severe scarring. Bladder-bowel dysfunction was present in 111 patients (28.9%). There was no significant correlation between BBD and UDR (p > 0.05). 62 patients showed spontaneous resolution in a median duration of 1.55 years. The predictive value of UDR for spontaneous resolution was more significant than grade (p < 0.001).There was no spontaneous resolution in patients with UDR over 0.45.321 patients underwent operation (248 endoscopic injection, 17 ureteroneocystostomy, 56 endoscopic injection+ureteroneocystostomy). When the predictive value of the reflux grade and UDR in the success rate of endoscopic correction was compared, UDR was shown to be significantly more predictive than the grade of reflux (p < 0.05). Ureteral diameter ratio was significantly higher in patients whose injection treatment was unsuccessful. Each 0.05 unit increase in UDR affected the success of endoscopic injection negatively (95% CI:<0.001-0.071).

CONCLUSION

Ureteral diameter ratio is an objective measurement of VUR and appears to be a new predictive tool for clinical outcome and success after endoscopic injection.