Preliminary data on endoscopic treatment of vesicoureteric reflux with polyacrylate polyalcohol copolymer (Vantris®): surgical outcome following single injection

A systematic review & meta-analysis comparing outcomes of endoscopic treatment of primary vesico ureteric reflux in children with polyacrylate poly alcohol copolymer versus dextranomer hyaluranic acid

BACKGROUND & AIMS

There are conflicting reports on the efficacy of bulking agents for vesico ureteric reflux (VUR). In this meta-analysis we have compared the outcomes of endoscopic treatment with polyacrylate polyalcohol copolymer (PPC) and dextranomer hyaluronic acid (DxHA).

METHODS

A systematic review of publications between 2010 and 2020 was conducted covering databases like PUBMED, MEDLINE etc. for (endoscopic treatment) AND (VUR) AND (PPC OR DxHA) AND (recurrence OR complications). PRISMA guidelines were followed and only comparative studies were included. Outcomes were early success defined as absence of VUR in voiding cystourethrogram at 3-months followup, urinary tract infections (UTI) and occurrence of vesico-ureteric-junction obstruction (VUJO). Risk of bias was analysed with Robvis tool and odds-ratios were compared with Revman-3.0.

RESULTS

Among nine studies (heterogeneity; I 2 69-79%) all cleared the risk of bias assessment. There was no significant difference in high grade VUR (p = 0.94) between PPC (40%) and DxHA (43%). Success rate after single injection was significantly higher (p = 0.0001) at 86% (477/555) for PPC vs 69% (474/685) for DxHA. UTI rate between PPC (12%) and DxHA (14.6%) was not statistically significant (p = 0.54). VUJO rate between PPC (3.9%) and DxHA (0.8%) was also not significantly different (p = 0.47). Significantly lesser volume (p = 0.02) was used for PPC (0.7 ml) compared to DxHA (0.9 ml).

CONCLUSION

Reflux resolution was significantly higher with PPC than DxHA. Postinjection UTI/VUJO incidence was not significantly different between them. Limitation of this meta-analysis was heterogeneity & small number of articles. Further studies should focus on long-term outcomes and cost-effectiveness.

Comparison of polyacrylate polyalcohol copolymer (PPC) and dextranomer/hyaluronic acid (Dx/HA) for treatment of vesicoureteral reflux. A systematic review and meta-analysis

PURPOSE

Our study aimed to compare the efficacy of polyacrylate polyalcohol copolymer and Dextranomer-Hyaluronic Acid for endoscopic treatment of vesicoureteral reflux.

MATERIAL AND METHODS

MEDLINE, EMBASE, Scopus, Web of science, Ovid, Cochrane databases, Google scholar have been searched for studies published until January 2022 in any language. Studies that compared the success rate for endoscopic treatment of vesicoureteral reflux in children with two bulking agents, namely, "polyacrylate polyalcohol copolymer." and "Dextranomer-Hyaluronic Acid" were included for this analysis.

RESULTS

Nine studies were included in data synthesis for this meta-analysis. Pooled data with a total of 763 ureters in PPC group and 718 ureters in Dx/HA group indicated that ureters in PPC group were more likely to undergo complete reflux resolution than Dx/HA (OR 3.80, 95% CI: 2.71; 5.31). Among subgroup of patients with high grade reflux, PPC injection had more resolution rate compared to Dx/HA patients (OR: 2.92, 95% CI: 1.19-7.16). In total, 95.81% of the PPC group and 86.52% of the Dx/HA group experienced success after the third injection. However a concerning complication of endoscopic treatment which is ureterovesical junction obstruction (UVJO) was more prevalent in PPC group. So the possible benefits arising from endoscopic treatment with PPC could be offset by the costs of re-implantation surgery or stenting in the case of UVJO.

CONCLUSION

These data indicate that PPC injection for vesicoureteral reflux treatment was associated with a higher success rate, but concerningly, UVJO incidence was higher in the PPC group which might negate the possible benefits of PPC injection However, due to the lack of studies with long-term follow-up, we couldn't reach a definitive conclusion about the superiority of one of the bulking agents over the other.

Endoscopic Correction of Reflux Utilizing Polyacrylate Polyalcohol Bulking Copolymer (Vantris) as a Tissue Augmenting Substance: Lessons Learned Over the 10 Years of Experience

Objectives: To prove the hypothesis that modifying the endoscopic correction of vesicoureteral reflux (VUR) technique (STING procedure) and sharpening its contraindications, lead to increased success rate and decline in the complication rate. Materials and Methods: All patients that underwent endoscopic correction of VUR utilizing Vantris were divided into two groups according to procedure date; before 2015 and 2015-2019. Indication for treatment included persistent high-grade VUR or breakthrough infections. Contraindications included voiding dysfunction, active infection and since 2015 suspicion for obstructive/refluxing ureterovesical junction (UVJ) presented by "beak" sign on voiding cystourethrography (VCUG). Follow-up regiment included ultrasound and VCUG at predetermined intervals. Results: The first group included 215 (158 girls and 57 boys) children with mean age of 4.8 ± 2.8 years who underwent endoscopic correction between 2009 and 2015 and the second group included 42 children (28 girls and 14 boys) with mean age of 3.9 ± 2.1 years who underwent surgery between 2015 and 2019. In the first group, VUR was unilateral in 74 patients and bilateral in 132 comprising 338 renal refluxing units. In the second group, VUR was unilateral in 14 patients and bilateral in 30 comprising 74 RRUs. In the first group reflux was corrected in 317 (94.9%) RRUs after a single injection, after the second in 7 (2.1%) RRUs. In seven (2.1%) RRUs, reflux downgraded to Grade I-II. Three RRUs (0.9%) failed endoscopic correction and required ureteral reimplantation. Nine (2.7%) RRUs developed UVJ obstruction. In the second group reflux was corrected in 61 (82.4%) RRUs after a single injection, after the second in 12 (16.2%) RRUs. In one (1.4%) RRU, endoscopic correction failed and required ureteral reimplantation. None of the patients developed UVJ obstruction. Reflux correction has led to the significant decrease of febrile urinary tract infection (UTI) in both groups. Conclusions: Our data indicate that endoscopic injection utilizing Vantris is safe and long durable procedure. Although utilizing the proper technique and contraindication criteria, the rates of post procedural VUJ obstruction is null.

The promise of regenerative medicine in the treatment of urogenital disorders

Polymers and scaffolds are the most significant tools in regenerative medicine. Urogenital disorders are an important group of diseases that greatly affect the patient's life expectancy and quality. Reconstruction of urogenital defects is one of the current challenges in regenerative medicine. Regenerative medicine, as well as tissue engineering, may offer suitable approaches, while the tools needed are appropriate materials and cells. Autologous urothelial cells obtained from biopsy, bone marrow-derived stem cells, adipose stem cells and urine-derived stem cells that expressed mesenchymal cell markers are the cells that mainly used. In addition, two main types of biomaterials mainly exist; synthetic polymers and composite scaffolds that are biodegradable polymers with controllable properties and naturally derived biomaterials such as extracellular matrix components and acellular tissue matrices. In this review, we present and evaluate the most appropriate and suitable scaffolds (naturally derived and synthetic polymers) and cells applied in urogenital reconstruction.

What are the predictive factors leading to ureteral obstruction following endoscopic correction of VUR in the pediatric population?

BACKGROUND

It is extremely important to not only address the short-term success following endoscopic correction of vesicoureteral reflux (VUR) but also the long-term efficacy and safety of the tissue augmenting substance utilized for endoscopic correction.

OBJECTIVE

This study retrospectively evaluated all cases of ureterovesical junction (UVJ) obstruction following endoscopic treatment of VUR over the last 5 years utilizing two tissue augmenting substances, with special emphasis on the safety of Vantris^®, and performed clinical and histological review of these patients.

METHODS

The study population comprised 2495 patients who underwent endoscopic correction of VUR utilizing Deflux^® (1790) and Vantris^® (705). Tissue sections were stained with hematoxylin & eosin and trichrome, and examined under a light microscope. Nine primary obstructive megaureters after ureteral re-implantation served as controls.

RESULTS

Nine (0.5%) children (three female and six male) in the Deflux group and nine (1.3%) (five females and four males) in the Vantris group developed UVJ obstruction and required ureteral re-implantation. Obstruction developed during the period ranging 2-49 months (average 16 months) following endoscopic correction. The primary reflux grade was III in seven, IV in six, and V in six children. The mean volume of the injected material in all obstructed patients was 1.2 ± 0.6 cc (mean ± SD). Histopathological analysis revealed a pseudocapsule composed of fibrous tissue and foreign-body giant cells surrounding the Vantris implant in all patients. The distal part of the ureters demonstrated significant ureteral dilatation without ureteral fibrosis. In all patients, additional biopsies from the muscularis propria adjacent to the injection site were examined and showed no significant abnormalities. There was an increased collagen deposition in the juxtavesical segment of the obstructive ureters following Deflux and Vantris injections, and of primary obstructive megaureter. No significant difference was found in the tissue response between Deflux and Vantris patients and controls. Statistical analysis of the nonhomogeneous population demonstrated higher obstruction rates in patients from the Vantris group. However, no statistical difference was demonstrated regarding the obstruction rate in the homogenous group with relation to gender, age and reflux grade group of patients. Moreover, univariate analysis revealed that Grade V reflux, the presence of beak sign on the reviewed pretreatment, and inflamed bladder mucosa upon injection were significant independent risk factors leading to obstruction.

DISCUSSION

This study suggested that the underlining ureteral pathology lead to UVJ obstruction following Vantris injection. There was increased collagen deposition in the juxtavesical segment of the obstructive ureters following Vantris injection. Furthermore, these findings were similar to those discovered in patients who underwent endoscopic correction with Deflux, and in patients who required ureteral reimplantation due to primary obstructive megaureter. Additional biopsies from the muscularis propria adjacent to the injection site showed no significant abnormalities, ironing out the fact that Vantris did not led to adverse tissue reaction following injection. Univariate analysis further ironed out the hypothesis that underlying ureteral pathology was responsible for the increased incidence of UVJ obstruction and demonstrated that Grade V reflux, the presence of beak sign on the reviewed pretreatment VCUG, and inflamed bladder mucosa upon injection were significant independent risk factors leading to obstruction.

CONCLUSION

Data showed that Vantris injection did not lead to any different ureteral fibrosis or inflammatory changes to the tissue augmenting substances utilized in past and present clinical practice, and therefore did not seem to increase the incidence of UVJ obstruction. High reflux grade, presence of obstructive/refluxing megaureter and inflamed bladder mucosa were the only statistically significant and independent predictive factors for UVJ obstruction following endoscopic correction of VUR.

Durasphere® EXP: a non-biodegradable agent for treatment of primary Vesico-Ureteral reflux in children

Introduction:

Durasphere^® EXP (DEXP) is a compound of biocompatible and non--biodegradable particles of zirconium oxide covered with pyrolytic carbon. The aim of this study is to evaluate the durability of off-label use of DEXP in the treatment of primary vesicoureteral reflux in children.

Materials and Methods:

Patients who underwent subureteric injection of DEXP for the correction of primary VUR were retrospectively reviewed. Patients aged >18 years as well as those who had grade-I or -V VUR, anatomic abnormalities (duplicated system, hutch diverticulum), neurogenic bladder or treatment refractory voiding dysfunction were excluded. Radiologic success was defined as the resolution of VUR at the 3rd month control. Success was radiographically evaluated at the end of the first year.

Results:

Thirty-eight patients (9 boys, 29 girls; mean age, 6.3±2.7 years) formed the study cohort. Forty-six renal units received DEXP (grade II: 22; grade III: 18; grade IV: 6). Mean volume per ureteric orifice to obtain the mound was 0.70±0.16mL. First con- trol VCUG was done after 3 months in all patients. After the first VCUG, 6 patients had VUR recurrence. Short-term radiologic success of DEXP was 84.2%. Rate of radiologic success at the end of the first year was 69.4% (25/32). Lower age (p:0.006) and lower amount of injected material (p:0.05) were associated with higher success rates at the end of 1 year.

Conclusion:

This is the first study to assess the outcomes of DEXP for treatment of primary VUR in children. After 1 year of follow-up, DEXP had a 69.4% success rate.

Endoscopic correction of vesicoureteral reflux in children using polyacrylate-polyalcohol copolymer (Vantris): 5-years of prospective follow-up

Introduction

The endoscopic correction of vesicoureteral reflux (VUR) in children is a currently well accepted therapy in many pediatric urology centers. Polyacrylate-polyalcohol copolymer (PPC), namely Vantris^®, is one of the tissue-augmenting substances used for endoscopic reflux therapy. The aim of this study was to evaluate the results with PPC in children.

Material and methods

From 2012 to 2016, 125 children (73 girls and 52 boys) aged 0.6–17.9 years (mean 4.9 ±3.58) were treated with PPC. VUR was unilateral in 64 and bilateral in 61 patients, comprising 197 renal refluxing units (RRUs) grades: II in 72, III in 50, IV in 33 and V in 42. Of these primary reflux was present in 132 RRUs and 65 were complex cases. Voiding cystourethrogram (VCUG) was done 3 months after procedure.

Results

Follow-up was completed in 89.6% of patients (112 children), and 89.8% of RRUs (177 out of 197). Reflux resolved in 86.4% of RRUs after single injection, in 99.4% after second and in 100% after the third. The only significant, but serious complication observed was late ureteral obstruction after PPC injection correcting high grade reflux, which required ureteral re-implantation. This complication was found in 9 out of 112 children (8%), and in 11 out of 177 RRUs (6.2%), 1.1 -2.9 years (mean 2 ±0.7) after the PPC injection. The longest follow-up reaches 4.5 years.

Conclusions

Our data show that the PPC injection is an effective procedure for treating all grades of VUR with high success rate. However, because of the possibility of late ureteral obstruction, which requires ureteroneocystostomy, long-term follow-up is mandatory.

Comparison of histopathological characteristics of polyacrylate polyalcohol copolymer with dextranomer/hyaluronic acid after injection beneath the bladder mucosa layer: a rabbit model

OBJECTIVES

To compare short- and long-term local tissue reaction of polyacrylate polyalcohol copolymer (PPC) with dextranomer/hyaluronic acid (DHA) in rabbits.

METHODS

Eight healthy New Zealand rabbits were randomly divided into two groups. In group I (control group), DHA was injected just beneath the mucosal layer of the bladder wall, while PPC was injected in group II. Subcutaneous injection of both bulking agents was also performed in nude mice. Histological evaluations with leukocyte common antibody (LCA), CD68, CD31, and CD34 were conducted on biopsies 1 and 6 months postoperatively. Scanning electron microscopy (SEM) and MTT assay were also performed for these two bulking agents.

RESULTS

SEM images revealed larger particle size of PPC. LCA and CD68 staining was significantly higher in group II as compared with group I in both short- and long-term follow-ups. However, in groups I and II, expression of CD31 (101 ± 0.5 vs. 92 ± 0.25, p > 0.05) and CD34 (115 ± 0.75 vs. 103 ± 0.5, p > 0.05) was not significantly different in long-term follow-up. Remarkably, severe fibrosis was observed in group II as compared to mild fibrosis in group I one month after injection. The results of in vivo application of these bulking agents in nude mice were in accordance with the results obtained from rabbit model. MTT assay revealed that cell proliferation was significantly higher in the presence of DHA as compared with PPC.

CONCLUSION

Severe inflammation and fibrosis in PPC may be due to continued foreign body reaction, presence of alcohol polymers, or larger particle sizes.

Endoscopic treatment of grades IV and V vesicoureteral reflux with two bulking substances: Dextranomer hyaluronic acid copolymer versus polyacrylate polyalcohol copolymer in children

PURPOSE

We aimed at evaluating the efficacy and complications of two bulking substances: dextranomer/hyaluronic acid copolymer(Dx/Ha;Dexell®) versus polyacrylate polyalcohol copolymer(PPC;Vantris®) in subureteric injection treatment of children with high grades (grades IV-V) vesicoureteral reflux(VUR).

METHODS

Data of patients undergoing endoscopic treatment of high grade VUR (January 2009-August 2015) were retrospectively investigated. Patients with high grade VUR caused by posterior urethral valve, duplex system, paraureteral diverticula and neurogenic bladder were excluded. Classical subureteric injection method (STING) was used. Seventy-three children (45 girls and 28 boys) who had 88 refluxing renal units (RRUs) with grades IV-V VUR (n=64/n=24) underwent endoscopic treatment using Dx/Ha (n=63 RRUs) and PPC (n=25 RRUs).

RESULTS

Mean age of patients in Dx/Ha and PPC groups were 6 (3) and 6 (3.75) year (p=0.81), and volumes of these substances given were 1.3 (1) and 1 (0.5) mL (p=0.003), respectively. Overall, for the first endoscopic injection, success rate of grades IV-V VUR per RRU was 53.9% with Dx/Ha, compared to 80% in PPC-injected group, (p=0.024). Late ureterovesical junction obstruction developed only in one patient in PPC-injected group. No ureteral obstruction was observed in Dx/Ha-injected group.

CONCLUSIONS

Endoscopic injection of PPC resulted in significantly higher success rate, compared to Dx/Ha in subureteric injection treatment of children with high grade VUR. However, the development of late ureterovesical junction obstruction should also be taken into account in PPC injection.

Comparison of results of endoscopic correction of vesicoureteral reflux in children using two bulking substances: Dextranomer/hyaluronic acid copolymer (Deflux) versus polyacrylate-polyalcohol copolymer (Vantris)

BACKGROUND

Endoscopic correction of vesicoureteral reflux (VUR) in children offers minimally invasive management and is widely used as a first-line procedure for all grades of reflux. However, there is debate about which tissue-augmenting substance is the best to use. The aim of this study was to evaluate the efficacy of two bulking substances, Deflux (Dx/HA) and Vantris (PPC), for endoscopic treatment of VUR in children.

METHODS

From 2009 to 2012, 65 children (50 girls and 15 boys) aged 1.45-9.9 years (mean 4.85 ± 2.52) underwent endoscopic correction of VUR using Deflux. VUR was unilateral in 31 patients and bilateral in 34 patients, comprising 108 renal refluxing units (RRUs) grades: II in 52, III in 47, IV in 7, and V in 2. From 2012, 68 children (43 girls and 25 boys) aged 0.6-17.9 years (mean 4.89 ± 3.46) were treated with Vantris. VUR was unilateral in 33 and bilateral in 35 patients, comprising 109 RRUs grades: II in 48, III in 29, IV in 13, and V in 19. Voiding cystourethrogram was done 3 months after procedure.

RESULTS

All patients completed follow-up (summary Table). With Deflux, reflux resolved in almost 93% of RRUs after two procedures (in 63% after first injection), with Vantris, VUR was corrected in the same percentage after one procedure.

DISCUSSION

The success rate with Deflux ranges between 68% and 92% (only 50-70% after single injection). The reported possibility of reflux recurrence after successful Deflux treatment, and the need for repeated injection led to introduction of the new substance Vantris. The results of a multi-centre survey published in 2014 showed that reflux is corrected in more than 90% of cases after single PPC injection. Our results with PPC confirm a high level of reflux resolution.

CONCLUSIONS

Our data show that Vantris injection is a safe and effective procedure for treating all grades of VUR with good clinical outcome, and provides a higher and almost complete level of reflux resolution after first injection compared with Deflux.

The outcomes of two different bulking agents (dextranomer hyaluronic acid copolymer and polyacrylate-polyalcohol copolymer) in the treatment of primary vesico-ureteral reflux

PURPOSE

Subureteral injection of bulking agents in the endoscopic treatment of vesicoureteral reflux is widely accepted therapy with high success rates. Although the grade of vesicoureteric reflux and experience of surgeon is the mainstay of this success, the characteristics of augmenting substances may have an effect particularly in the long term. In this retrospective study, we aimed to evaluate the clinical outcomes of the endoscopic treatment of vesicoureteric reflux (VUR) with two different bulking agents: Dextranomer/hyaluronic acid copolymer (Dx/HA) and Polyacrylate polyalcohol copolymer (PPC).

MATERIALS AND METHODS

A total 80 patients (49 girls and 31 boys) aged 1-12 years (mean age 5.3 years) underwent endoscopic subureteral injection for correction of VUR last six years. The patients were assigned to two groups: subureteral injections of Dx/HA (45 patients and 57 ureters) and PPC (35 patients and 45 ureters). VUR was grade II in 27 ureters, grade III in 35, grade IV in 22 and grade V in 18 ureters.

RESULTS

VUR was resolved in 38 (66.6%) of 57 ureters and this equates to VUR correction in 33 (73.3%) of the 45 patients in Dx/HA group. In PPC group, overall success rate was 88.8% (of 40 in 45 ureters). Thus, Thus, this equates to VUR correction in 31 (88.5%) of the 35 patients.

CONCLUSIONS

Our short term data show that two different bulking agent injections provide a high level of reflux resolution and this study revealed that success rate of PPC was significantly higher than Dx/HA with less material.

The use of polyacrylate-polyalcohol copolymer hydrogel in the endoscopic treatment of primary vesicoureteral reflux in children

BACKGROUND/PURPOSE

It is still under discussion which is the best tissue augmenting substance for the endoscopic treatment of children with vesicoureteral reflux (VUR). We describe our preliminary experience (September 2009-November 2011) with polyacrylate-polyalcohol copolymer hydrogel (PPCH).

METHODS

This is an observational, descriptive, prospective study which included 81 female and male patients (age 1-14 years) diagnosed with unilateral (n=45) and bilateral (n=36) primary VUR comprising a total of 117 refluxing renal units (RRU). Complex cases were excluded from the study. All patients were clinically and radiologically evaluated and those who met the inclusion criteria were treated endoscopically with a single subureteral injection of PPCH by a single surgeon. 11 patients (13.5%) had a pathological 99mTc-DMSA before treatment. The volume of injected product was measured in all cases. Results were considered successful if 6months postinjection, conventional voiding cystourethrogram (VCUG) revealed VUR was cured (Grade 0). Follow-up ranged from 7 to 32months.

RESULTS

The overall resolution rate based on the number of RRUs studied was 92.3% (108/117). The mean injected volume of PPCH per patient was 0.6ml. One patient with obstructive anuria required vesicoureteral reimplantation. Other complications were persistent, self-limiting hematuria (n=2); lumbar pain (n=4) and urinary tract infection with normal VCUG (n=4).

CONCLUSIONS

Our short term data show PPCH provides a high level of reflux resolution in selected patients. Long term follow-up is required.

Endoscopic correction of primary VUR by using polyacrylate polyalcohol copolymer (Vantris) in young girls: 2-year follow-up

OBJECTIVE

Our aim was to evaluate the efficacy and safety of single endoscopic injection of Vantris in young girls affected by primary vesicoureteral reflux (VUR) at more than 2 years of prospective follow-up.

MATERIAL AND METHODS

Over the last 4 years, 73 girls with primary VUR of grades (G) I-IV underwent a single endoscopic injection of Vantris. The mean age was 8.48 (SD=4.8) years. VUR was unilateral in 73 and bilateral in 13 patients, comprising 86 renal refluxing units (RRUs). Pre-operative evaluation consisted of: blood biochemistry, urine analysis and culture, ultrasound scan, voiding cystourethrogram (VCUG), and dimercaptosuccinic acid (DMSA) renal isotope scan. Patients were followed using ultrasound scans at 1 month and every 3 months for the first year and then 2 years after injection. Direct radionuclide cystography with technetium pertechnetate was performed at 3 and 12 months after injection. VCUG was performed only in confirmed cases of failure and downgraded VUR at 3, 12, and 24 months after endoscopic correction.

RESULTS

Sixty-nine (95%), 61 (83.4%), and 52 (71%) patients completed 3, 12, and 24 months' follow-up respectively. VUR was corrected and downgraded to G I in 81% and 3.3% of RRUs at 3 months' follow-up. The corrected and downgraded RRUs at 12 and 24 months' follow-up were 77%, 10%, and 77%, 11% respectively. De novo contralateral G I VUR was demonstrated in 8.6% of normal ureters. Contralateral GI VUR with normal DMSA isotope renal scans was resolved in 71% of RRUs. Febrile urinary tract infection decreased to 4.1% in the patients.

CONCLUSION

According to our study, a single Vantris injection provides a high level of efficacy and safety in the treatment of primary G I-IV VUR in young girls, at 2 years' prospective follow-up.

Open ureteroneocystostomy after failed endoscopic injection with three different bulking agents for the treatment of vesicoureteral reflux

BACKGROUND/PURPOSE

To evaluate the success rate of open ureteroneocystostomy (UNC) after failed endoscopic treatment of vesicoureteral reflux (VUR) in children and to discuss the reasons for failure under the light of histopathological findings.

METHODS

The clinical data of 371 patients who underwent endoscopic injection for VUR at our institution for the treatment of VUR between January 2008 and January 2014 were reviewed. Patients who were submitted to open ureteral reimplantation following failed endoscopic injection were included in the study.

RESULTS

Among 371 patients, 34 (49 ureters) were submitted to open UNC (9.1%). There were 22 female and 12 male patients. Three different injection materials were used; dextranomer/hyaluronic acid in 29, carbon-coated beans in 7 and polyacrylate polyalchohol copolymer in 13. Histological study revealed that the injected material was identified in 34 ureters as malpositioned. Control VCUG 6 months after UNC showed complete resolution in 46 of 47 ureters (97.87%).

CONCLUSIONS

Previous endoscopic injection, although causing difficulty in dissection to some degree, does not alter the success rate of UNC. According to the histopathological findings, the cause of failure of injection seems to be attributable to incorrect plane of injection or leakage of the agent after injection.

A comparison of the double hydrodistention implantation technique (HIT) and the HIT with a polyacrylate/polyalcohol copolymer (PPC) for the endoscopic treatment of primary vesicoureteral reflux

OBJECTIVES

We aimed to compare the success rates of the double hydrodistention implantation technique (HIT) and the HIT with a polyacrylate/polyalcohol copolymer (PPC) for the treatment of primary vesicoureteral reflux (VUR) with a new nonbiodegradable tissue-augmenting substance (Vantris, Promedon, Cordoba, Argentina).

METHODS

Between January 2011 and December 2012, fifty-two children who underwent subureteric injection for primary VUR are included. The children were randomly separated into two groups, the HIT and the double HIT groups, according to the type of injection. Success was defined as no reflux on a follow-up voiding cystourethrogram (VCUG) after 6 months. The patients were evaluated according to sex, age, grade of reflux, number of injections, and injected volume, and the radiological success rates were compared.

RESULTS

Fifty-two patients underwent an endoscopic injection for primary grade III-V VUR. The HIT group consisted of 26 patients with 33 ureters, and the double HIT group consisted of 26 patients with 35 ureters. There were no significant differences in terms of the sex, ages, VUR grades, bilaterality between the two groups. The mean injected volumes were ml 1.12 (1.02-1.22) in the HIT group and 1.24 ml (95 % CI 1.10-1.38) in the double HIT group. The reflux was resolved in 21/33 (63.6 %) ureters in the HIT group and in 30/35 (85.7 %) ureters in the double HIT group, (p < 0.05). We had only one complication. This patient in the double HIT group, developed bilateral hydronephrosis and oliguric renal failure requiring open reimplantation at the sixth month.

CONCLUSION

We observed successful results double HIT method with PPC in Grade III-V reflux, but the long-term follow-up of patients is needed for hydronephrosis. As the double HIT treatment leads to a higher success rate, its use is preferable.

Endoscopic correction of complex cases of vesicoureteral reflux utilizing Vantris as a new non-biodegradable tissue-augmenting substance

PURPOSE

We aimed to evaluate prospectively the efficacy of Vantris as a new non-biodegradable tissue-augmenting substance in children with complex cases of VUR.

MATERIALS AND METHODS

Over the last 4 years, 37 children (28 female and 9 male) with a mean age of 5.8 ± 3.1 years (mean ± SD) underwent endoscopic correction of complex VUR. A total of 38 renal refluxing units (RRU) was treated as 5 had persistent reflux after open surgery, 16 had duplication, 4 had Hutch diverticulum, 6 had small poorly functioning kidneys (less than 20% of relative renal function) with grade V VUR, 2 had ureterocele after puncture, 3 had persistent stump reflux, 1 had prune belly syndrome, and 1 had urogenital sinus. VUR was Grade I in 2, Grade II in 9, Grade III in 11, Grade IV in 10, and Grade V in 6 RRU, respectively.

RESULTS

The reflux was corrected in 34 (89.4%) RRU after a single injection, after second injection in 2 (5.3%) RRU. In 2 (5.3%) RRU, VUR downgraded to Grade I (1RRU) and Grade II (1RRU) and they were taken off antibiotic prophylaxis. VCUG was performed in 11 (73.3%) of 15 children who completed 1 year and in 3 (33.3%) of 9 who completed 3 years of follow up as a part of the routine protocol. None showed VUR recurrence. US demonstrated normal appearance of kidneys in all patients.

CONCLUSION

Our data show that Vantris injection provides a high level of reflux resolution in complex cases of VUR.

Combination of calcium hydroxyapatite and autologous blood for endoscopic treatment of vesicoureteral reflux in children

OBJECTIVE

To report the results of endoscopic correction of vesicoureteral reflux (VUR) with concomitant injection of pure calcium hydroxyapatite (CaHA) and autologous blood.

PATIENTS AND METHODS

Records of patients who underwent endoscopic correction of VUR using concomitant injection of CaHA and autologous blood from 2008 through 2010 were retrospectively reviewed. Data regarding patients' demographics, preoperative VUR grades, febrile urinary tract infections, complications of procedure, postoperative VUR grades and cure rates were collected. Voiding cystourethrography was performed 3 months postoperatively.

RESULTS

Total number of 23 children (9 girls and 14 boys) with 40 refluxing ureters were included. The mean age of children was 1.9 ± 0.97 (SD) years. Reflux grades were II to IV in 14, 11 and 15 renal refluxing units (RRUs), respectively. The mean follow-up period was 44 months. VUR was successfully treated in 87.5% of RRUs after three injections. Significant statistical difference was found between VUR grades before and after the first, second and third injections (p < 0.001, p = 0.001 and p = 0.011, respectively). Moreover, there was a significant difference between primary reflux grade and treatment success (p = 0.031). Febrile UTI was resolved in 85% of patients (17 of 20 patients with febrile UTI) after endoscopic treatment which shows significant improvement (p < 0.001). The procedure was uneventful in all patients, and no obstruction was reported during the follow-up period.

CONCLUSION

Concomitant injection of pure CaHA without any additives (hyaluronic acid, etc.) and autologous blood can be an effective, repeatable and cost-benefit approach for the management of children suffering VUR with a success rate of 87.5% after three injections.

Prospective study using a new bulking agent for the treatment of vesicoureteral reflux: polyacrylamide hydrogel

PURPOSE

Vesicoureteral reflux is frequently diagnosed in the pediatric population. Endoscopic treatment has become a popular form of first-line therapy. Available products offer good short-term success rates. However, the cost of these injected implants is an issue. We evaluated the success of endoscopic treatment for vesicoureteral reflux using polyacrylamide hydrogel.

MATERIALS AND METHODS

We performed a single center, single surgeon, prospective, off-label study using polyacrylamide hydrogel to treat vesicoureteral reflux. All patients underwent endoscopic subureteral double hydrodistention implantation technique injection followed by renal ultrasound and voiding cystourethrogram at 3 months postoperatively to confirm the absence of de novo hydronephrosis and correction of vesicoureteral reflux (grade 0).

RESULTS

A total of 40 patients (69 refluxing ureters) underwent polyacrylamide hydrogel injection. Median age at surgery was 50 months. Bilateral reflux was identified in 29 patients (73%). Nine patients had duplex systems, 2 with reflux into both moieties. Reflux was graded using the International Reflux Study in Children grading system, with grade I seen in 9 ureters, II in 17, III in 20, IV in 18 and V in 5. Mean volume injected was 1.1 ml. Success rate for grade I to III vesicoureteral reflux at 3 months after a single treatment was 87%, and the overall success for all grades was 81.2%.

CONCLUSIONS

Off-label use of polyacrylamide hydrogel injection therapy for primarily low grade vesicoureteral reflux demonstrates that the technique and short-term success rates are comparable to the most popular bulking agent, dextranomer/hyaluronic acid. These results suggest that further trials comparing polyacrylamide hydrogel and dextranomer/hyaluronic acid would be worthwhile.

The influence of ureteral orifice configuration on the success rate of endoscopic treatment of vesicoureteral reflux

Background:

To investigate the effect of polyacrylate polyalcohol copolymer (Vantris) injection for the correction of VUR in children according to ureteral orifice shape and VUR grade.

Materials and Methods:

Forty children (29 girls and 11 boys) with 61 renal refluxing units (RRU) and primary VUR underwent endoscopic correction of their reflux, using Vantris. Under general anesthesia, routine cystoscopy was performed and ureteral orifice configuration and dynamic hydro distention grade were determined. The injection technique was STING, HIT or a combination of them. Ultrasound scan was performed one and 3 months after injection and radionuclide cystography (RNC) was performed 3 months after the operation.

Results:

The mean volume of injected Vantris was 0.62 cc. Reflux was corrected in 52 (85.2%) of the 61 RRU after single injection and this equates reflux correction in 37 of the 40 patients. No significant correlation was observed between ureteral orifice shape and VUR correction rate.

Conclusions:

Our results showed that there was no correlation between the ureteral orifice configuration and the success rate of endoscopic surgery for VUR in short term.