Nonhomologous bioinjectable materials in urology: 'size matters'?

Endoscopic injection of bulking agents in pediatric vesicoureteral reflux: a narrative review of the literature

In the last 20 years, endoscopic injection (EI) has affirmed as a valid alternative to open surgery for management of pediatric vesicoureteral reflux (VUR). This study aimed to investigate and discuss some debated aspects such as indications, bulking agents and comparison, techniques of injection and comparison, predictive factors of success, use in specific situations. EI is minimally invasive, well accepted by patients and families, with short learning curve and low-morbidity profile. It provides reflux resolution rates approaching those of open reimplantation, ranging from 69 to 100%. Obviously, the success rate may be influenced by several factors. Recently, it is adopted as first-line therapy also in high grade reflux or complex anatomy such as duplex, bladder diverticula, ectopic ureters. The two most used materials for injection are Deflux and Vantris. The first is absorbable, easier to inject, has lower risk of obstruction, but can lose efficacy over time. The second is non-absorbable, more difficult to inject, has higher risk of obstruction, but it is potentially more durable. The two main techniques are STING and HIT. To date, the ideal material and technique of injection has not yet clearly established, but the choice remains dependent on surgeon's preference and experience.

Bladder Dysfunction and Re-Absorbable Bulking Agent Affect Success Rate in Children Underwent Endoscopic Treatment for Vesicoureteral Reflux: A Long-Term Follow-Up Study

This paper is designed to evaluate the results (at long-term follow-up of) children affected by dilating VUR. Our attention was focused on how VUR grade, laterality, bladder dysfunction (BD), the double renal system, and the type of bulking substance may affect VUR resolution in the long-term period. The charts of 93 children with dilating VUR who underwent endoscopic treatment (ET) and with a minimum post-operative follow-up of 7 years were reviewed (mean follow-up time was 9.6 + 1.4). The majority of patients had severe and bilateral VUR. Polydimetilsiloxane or hyaluronic acid/dextranomer (PDS or Ha/Dx) were used as bulking agents. VUR persistence following endoscopic injection was independent with respect to grade, laterality, duplex renal system, and BD. However, the rate of VUR persistence was significantly higher in children with BD. Children treated with Ha/Dx had a higher rate of VUR persistence. This research demonstrated that ET of VUR is also effective at very long term follow up (and without the development of significant complications). We also showed that patients treated with absorbable bulking agents such as Ha/Dx may experience a higher recurrence rate at the long-term follow-up). We also confirm that the only preoperative condition affecting VUR recurrence was bladder dysfunction.

Brazilian consensus on vesicoureteral reflux-recommendations for clinical practice

Introduction

Vesicoureteral Reflux (VUR) is characterized by a retrograde flow of urine from the bladder into the ureters and kidneys. It is one of the most common urinary tract anomalies and the major cause of urinary tract infection (UTI) in the first years of life. If not properly diagnosed and treated can lead to recurrent UTI, renal scar and, in severe cases, to end stage renal disease. Despite recent advances in scientific and technological knowledge, evaluation and treatment of VUR is still controversial and there is still considerable heterogeneity in evaluation methods and therapeutic approaches. The aim of the present consensus is to give a practical orientation on how to evaluate and treat VUR.

Methods

The board of Pediatric Urology of the Brazilian Society of Urology joined a group of experts and reviewed all important issues on Vesicoureteral Reflux evaluation and treatment and elaborated a draft of the document. On November 2017 the panel met to review, discuss and write a consensus document.

Results and Discussion

Vesicoureteral Reflux is a common and challenging problem in children. Children presenting with Vesicoureteral Reflux require careful evaluation and treatment to avoid future urinary tract infections and kidney scars. The panel addressed recommendations on up to date choice of diagnosis evaluation and therapies.

Endoscopic injection therapy

Since the U.S. Food and Drug Administration approved dextranomer/hyaluronic acid copolymer (Deflux) for the treatment of vesicoureteral reflux, endoscopic injection therapy using Deflux has become a popular alternative to open surgery and continuous antibiotic prophylaxis. Endoscopic correction with Deflux is minimally invasive, well tolerated, and provides cure rates approaching those of open surgery (i.e., approximately 80% in several studies). However, in recent years a less stringent approach to evaluating urinary tract infections (UTIs) and concerns about long-term efficacy and complications associated with endoscopic injection have limited the use of this therapy. In addition, there is little evidence supporting the efficacy of endoscopic injection therapy in preventing UTIs and vesicoureteral reflux-related renal scarring. In this report, we reviewed the current literature regarding endoscopic injection therapy and provided an updated overview of this topic.

Endoscopic treatment of vesicoureteral reflux in pediatric patients

Endoscopic treatment is a minimally invasive treatment for managing patients with vesicoureteral reflux (VUR). Although several bulking agents have been used for endoscopic treatment, dextranomer/hyaluronic acid is the only bulking agent currently approved by the U.S. Food and Drug Administration for treating VUR. Endoscopic treatment of VUR has gained great popularity owing to several obvious benefits, including short operative time, short hospital stay, minimal invasiveness, high efficacy, low complication rate, and reduced cost. Initially, the success rates of endoscopic treatment have been lower than that of open antireflux surgery. However, because injection techniques have been developed, a recent study showed higher success rates of endoscopic treatment than open surgery in the treatment of patients with intermediate- and high-grade VUR. Despite the controversy surrounding its effectiveness, endoscopic treatment is considered a valuable treatment option and viable alternative to long-term antibiotic prophylaxis.

Local giant cell foreign body reaction after silicone injection for fecal incontinence in humans: two case reports

Since the 1990s, one of the methods used for treating fecal incontinence due to internal anal sphincter defects has been the injection of bulking agents. The aim of this paper is to report two cases of local giant cell foreign body reaction after injection of PTQ(TM) in humans. To the best of the authors' knowledge, this is the first report of an adverse immune response to silicone injection in humans.

Effect of the Macroplastique Implantation System for stress urinary incontinence in women with or without a history of an anti-incontinence operation

INTRODUCTION AND HYPOTHESIS

We evaluated the outcomes and the effect of the Macroplastique Implantation System on the quality of life in women with stress incontinence with or without a history of an anti-incontinence operation during 12 to 62 months follow-up.

METHODS

Thirty-five women with urodynamically proven stress incontinence with intrinsic sphincter deficiency were included in this study. Macroplastique injection was performed in all patients. Quality of life was evaluated prior to therapy, in early postoperative time (at the sixth weeks) and in late postoperative time (12 to 62 months follow-up) with the use of three different questionnaires: Incontinence Quality-of-Life Questionnaire (I-QOL), Incontinence Impact Questionnaire-7 (IIQ-7), and Urogenital Distress Inventory-6 (UDI-6). Questionnaires were also compared with those previous to the anti-incontinence operation and to the primary procedure groups.

RESULTS

The median age of the women was 50.00 (interquartile range = 17.00) years. There were 24 primary procedures and 11 had undergone previous anti-incontinence surgery. Maximum follow-up time was 62 months, minimum follow-up time was 12 months, and the median follow-up time of the study was 58 (interquartile range = 44-60) months. When preoperative and postoperative median of the I-QOL, IIQ-7, and UDI-6 scores were compared, the differences between scores were found to be statistically significant. I-QOL, IIQ-7, and UDI-6 scores were related to the previous surgery. The overall I-QOL, IIQ-7, and UDI-6 summary scores showed high internal consistency.

CONCLUSIONS

The Macroplastique injection system is an effective, safe, and acceptable option for stress urinary incontinence in women with or without a history of an anti-incontinence operation. Moreover, it can be performed under local anesthesia without cystoscopic guidance; moreover, side effects are rare.

[Vesico-ureteric reflux treatment by implant of polydimethylsiloxane (Macroplastique): Review of the literature]

PURPOSE

During the last 25years, endoscopic correction of vesicoureteral reflux (VUR) has become a well-recognized procedure. However, the nature of the bulking agent used has led to many controversies. The objective of this work was to perform a literature review on the use of polydimethylsiloxane (PDMS or Macroplastique) in VUR.

METHOD

A PubMed review of the literature since 1996 resulted in the selection of 24 studies of sufficient level of evidence to assess the efficacy and tolerance of Macroplastique in the VUR in adults and children.

RESULTS

The overall success rate at 1 year, 2 years and 9-years follow-up was respectively 86-93 %, 80-92 %, and 77-100 %, which confirms the maintenance of good results over time, notably in VUR grade III and above. The success rate was similar for primary and secondary VUR except for total duplicity. Predictive criterias of success were the surgeon's experience, the low grade of VUR, and the absence of previous injection. In comparison with other bulking agents, the higher viscosity and absence of shrinkage of the product increase its reliability. After more than 12years of use, no serious complication has been reported in the literature, reflecting the good tolerance of Macroplastique on the long term.

CONCLUSION

The studies published on the use of Macroplastique in VUR confirmed its efficacy, around 85 % of success for all grades, in children and adults as well. The interest of PDMS is linked to its higher viscosity promoting a better reliability and reproducibility of the technique and its non-resorbable nature providing a permanent result, especially valuable in high-grade VUR with anatomical anomaly of the vesicoureteral junction or in VUR secondary to permanent lower urinary tract dysfunction.

Effects of Macroplastique Implantation System for stress urinary incontinence and urethral hypermobility in women

A study was carried out to evaluate efficacy of Macroplastique(R) (MPQ) Implantation System (MIS) in women with urodynamic stress urinary incontinence (SUI) and urethral hypermobility after an unsuccessful conservative treatment. This is a prospective randomized controlled trial in women without previous incontinence surgery. Twenty-four women received MPQ. Twenty-one controls underwent a pelvic floor muscle exercises home program. Follow-up was at 3 months and the MPQ group also at 12 months. At 3 months, pad usage decreased significantly more in the MPQ group than in the control group (p = 0.015). According to physician and patient self-assessment, respectively, 71% and 63% women in the MPQ group were considered cured or markedly improved. This was significantly higher compared to controls. There was a significant higher increase of Incontinence Quality-of-Life questionnaire score in the MPQ group compared to controls (p = 0.017). Improvements in MPQ group at 3 months are sustained to 12 months. Adverse events were mild and transient. MIS is an acceptable option for women with SUI and urethral hypermobility.

Emerging periurethral bulking agents for female stress urinary incontinence: is new necessarily better?

Bulking therapy for stress urinary incontinence in women continues to evolve from the standpoint of material science. Several new materials have recently been subjected to clinical trials with the aim of assessing efficacy and safety of these agents for possible device registration. These new additions run the gamut of biologic to synthetic materials, including re-engineered carbon-coated zirconium beads, ethylene vinyl copolymer, calcium hydroxylapatite, silicone, and hyaluronic acid. Trial design and results reporting for bulking agents has also evolved, with the addition of quality-of-life and patient approbation assessments now being included with outcomes for incontinence reduction and adverse events recording. The new agents and recent studies are reviewed within a context of the prior evidence that has supported the use of the bulking strategy for management of symptomatic stress incontinence. Several recent trials have also compared bulking agents with surgical interventions from effectiveness, approbation, and cost vantage points so as to better determine the reasonability of bulking agent use in an era of minimally invasive incontinence surgery.

Stress incontinence injection therapy: what is best for our patients?

OBJECTIVE

Urethral injection (periurethral/intraurethral bulking) is an established, minimally invasive therapy for stress urinary incontinence (SUI). This review aims to determine which women should potentially benefit from, and be considered as candidates for, injection therapy and to elucidate what we are trying to achieve.

METHODS

Based on MEDLINE database searches, all aspects of urethral injection were examined, including patient selection, safety, injection technique, efficacy, quality of life, goals and cost.

RESULTS

Such therapy has a low complication rate, improves or cures about 3 out of 4 women, as shown in mainly short-term studies, and improves patients' quality of life. It can be used in the majority of patients with uncomplicated SUI. Therefore, injection therapy may be considered as a first-line treatment option for patients who have failed conservative therapy such as pelvic floor exercises and who decline or have a contraindication for pharmacological treatment. However, the decision of whether to use this type of treatment must be based on an informed discussion between the physician and patient--this dialogue should incorporate questions about patients' own treatment goals. Injection therapy appears to have the profile required to meet patients' goals, based on the findings that a procedure with an improvement in incontinence, minimal short-term risk, no long-term risk, and performed in a clinic, would be acceptable.

CONCLUSION

Investigating and trying to achieve patients' own treatment goals will ultimately enable us to do what is best for our patients, but current evidence suggests that injection therapy is a valid option worth discussing with many patients.

Endoscopic treatment with polydimethylsiloxane in children with dilating vesico-ureteric reflux

OBJECTIVE

To report our experience of treating dilating vesico-ureteric reflux (VUR) in children, using an injectable form of polydimethylsiloxane (Macroplastique, MPQ; Uroplasty BV, Geleen, The Netherlands), as medical treatment for moderate or severe VUR is associated with a high proportion of persistence or development of new scars.

PATIENTS AND METHODS

The study included 32 children (40 ureters) with VUR; 13 (32%) were grade III, 20 (50%) grade IV and seven (18%) grade V. They were treated over a period of 42 months, 66% for some form of bladder dysfunction and 38% had associated diseases. The main indications were VUR grade, recurrent urinary tract infection and progression of reflux nephropathy. MPQ was injected under general anaesthesia via an 11 F cystoscope, x 30 objective, with a 5 F working channel.

RESULTS

The mean (sd) follow-up was 28.5 (10.2) months; VUR resolved in 80% of patients and improved to minimal VUR in the remaining 20%. The resolution/improvement rate was 72% after the first injection, 97% after the second and 100% after the third. There were no significant complications.

CONCLUSION

The endoscopic implantation of MPQ always corrected VUR even though 68% of the cases were grade IV-V. It should become the treatment of choice for severe VUR.

Injection therapy for stress urinary incontinence in adult women

Stress urinary incontinence (SUI) is prevalent in adult women and has a considerable impact on quality of life. However, it often remains undiagnosed and therefore untreated. Noninvasive treatment is likely to be offered in mild cases and may entail pelvic floor muscle re-education, minimally invasive devices or pharmacotherapy. Surgical intervention is widely considered as the only effective option for more severe SUI, although it is not suitable for all patients. Injection therapy with urethral bulking agents represents an alternative minimally invasive procedure and can be used for all types of SUI. Many bulking agents have been developed, although the ideal remains to be discovered. The safety and durability of agents remain a concern. No differences in agents from an efficacy point of view have been found. For many years urethral injection could only be administered endoscopically. The recent development of devices for blind injection has increased the speed and convenience of urethral injection, removing the need for surgical facilities. The subjective cure rate after injection therapy is higher than the objective one. A focus on the patient's wishes and expectations with respect to success and risks of a treatment for SUI is required. In addition, randomized clinical trials are mandatory to establish the place and efficacy of urethral bulking agents compared with conservative therapy (pelvic floor muscle re-education) in treating SUI in adult women.

Treatment of incontinence after prostatectomy using a new minimally invasive device: adjustable continence therapy

OBJECTIVE

To evaluate the safety and efficacy of a new minimally invasive urological implant for incontinence after prostatectomy.

PATIENTS AND METHODS

The adjustable continence therapy device (ProACT, Uromedica, Plymouth, MN, USA) consists of two balloons placed via a perineal approach bilaterally at the bladder neck in patients after prostatectomy. Titanium ports, attached via discrete tubing to each balloon, are placed in the scrotum, allowing for separate volume adjustments of the balloons at any time during and after surgery. Changes in a quality-of-life questionnaire (I-QoL), pad usage and a subjective continence grading score were assessed in 117 consecutive men after implanting the Pro-ACT, at baseline and at 1, 3, 6, 12 and 24 months.

RESULTS

After a mean (range) follow-up of 13 (3-54) months and with a mean of 3 (0-15) adjustments, 67% of men were dry, using at most one 'security' pad daily; 92% were significantly improved, and 8% showed no improvement. The I-QoL score improved from a median of 34.7 to 66.3 after 2 years (42 men; P < 0.001), the daily pad count decreased from a mean of 6 (1-24)/day to 1 (0-6)/day at 2 years (P < 0.001). Continence achieved at < or = 6 months after implantation through incremental adjustment remained durable at > or = 2 years in most patients. There were complications during and after surgery in 54 patients, mostly minor and decreasing with increasing expertise, primarily reflecting the development and refinement of the new surgical technique and its instrumentation. Re-implantation for complications was required in 32 patients, with a 75% success rate.

CONCLUSIONS

The ProACT peri-urethral prosthesis produces durable outcomes equivalent or better than other minimally invasive treatments for incontinence after prostatectomy. Its unique design allows for easy adjustment after surgery to achieve the desired urethral resistance, with no further surgical intervention, thus allowing for an optimum balance between voiding pressures and continence. The promising results reported here suggest that this may be an appropriate, effective and durable first-line treatment to offer men with stress urinary incontinence after prostatectomy.

[Subureteral polydimethylsiloxane injection for the endoscopic treatment of vesicoureteral reflux]

INTRODUCTION

Endoscopic subureteral injection has been successfully used to treat vesicoureteral reflux (VUR) in children. The aim of this study was to review our results with subureteral polydimethylsiloxane injection in terms of effectiveness, long term follow-up and morbidity.

MATERIAL AND METHOD

Twenty-eight children with VUR were treated with this technique. VUR was unilateral in eight patients (28.6%) and bilateral in 20 patients (71.4%). Indications for endoscopic treatment were the same as those for open surgery. The polydimethylsiloxane implant was injected transureterally below the ureteral meatus in 50 ureters on an outpatient basis. Reflux grade was low (II-III) in 36% and high (IV-V) in 64%.

RESULTS

The mean follow-up was 18 months (12 months-4 years). VUR was corrected in 43 ureters (86%) corresponding to 21 patients. Reflux resolved in 40 ureters after one polydimethylsiloxane injection (80%) and in 43 ureters (86%) after two injections. An endoscopic retreatment to correct the reflux was performed in six ureteral units. Cystoscopic findings in these patients with endoscopic failure were mound displacement toward the bladder neck in five ureters and marked volume loss on the mound in one. All these patients underwent a second subureteral dose, which controlled VUR in three ureters (50%).

CONCLUSIONS

Our results confirm that endoscopic subureteral polydimethylsiloxane treatment is a simple procedure with low morbidity that is well tolerated by the patient. In our experience, it can be used in double ureters. The effectiveness of this procedure seems to be related to the grade of reflux, the cystoscopic appearance of the ureteral orifice, volume loss and mound displacement.

The long-term outcome of the endoscopic subureteric implantation of polydimethylsiloxane for treating vesico-ureteric reflux in children: a retrospective analysis of the first 195 consecutive patients in two European centres

OBJECTIVE

To determine the long-term efficacy of endoscopically implanting polydimethylsiloxane (PDS, Macroplastique, Uroplasty BV, Geleen, the Netherlands) for treating vesico-ureteric reflux (VUR) in children.

PATIENTS AND METHODS

We retrospectively reviewed the records of 195 children treated with PDS over the past 10 years in two European centres (Netherlands and UK) and conducted follow-up investigations where deemed necessary. In the Dutch centre patients were treated according to a prospective approved study protocol.

RESULTS

Of the 195 treated children, 155 had a successful outcome; in all, 311 refluxing renal units were treated, with an overall success rate of 82.3% in a mixed group of patients with unilateral or bilateral VUR and duplex systems.

CONCLUSION

The long-term data from these two independent centres confirms the viability of PDS and the technique for treating VUR in children. We conclude that the material is safe and effective and can be used in VUR grades II-V. Treating patients with grade I VUR is recommended in those cases where there is no spontaneous resolution and 'breakthrough' infections.

Systematic review: efficacy of silicone microimplants (Macroplastique) therapy for stress urinary incontinence in adult women

OBJECTIVE

To assess the efficacy of silicone microimplants (Macroplastique; polydimethylsiloxane) therapy for stress urinary incontinence in adult women, using a systematic review of identified studies.

MATERIALS AND METHODS

A computer-aided and manual search for published studies investigating silicone microimplants therapy for stress urinary incontinence in adult women. The methodological quality of the included studies was assessed using criteria based on generally accepted principles of interventional research.

RESULTS

Only two RCTs, only published as an abstract, were found. Eleven pre-experimental or observational studies were identified. Overall, the methodological quality was low. The main methodological shortcomings of the studies were: no random allocation procedure, lack of prestratification on prognostic determinants, no blinding, small sample sizes, and lack of proper analysis and presentation of results. There was variability in the indication for implantation, implantation procedure, rate and volume of silicone microimplants. The use of different outcome measures in most of the trials made comparison between studies difficult.

CONCLUSIONS

Because of the low methodological quality of included studies, results should be interpreted with caution and no firm conclusions about the efficacy of silicone microimplants were possible. Randomized clinical trials, using valid and reliable subjective and objective measurements, are necessary to establish the efficacy of silicone microimplants therapy in treating stress urinary incontinence in adult women.

Intravenous in-line filters: filtering the evidence

PURPOSE OF REVIEW

The routine use of intravenous in-line filters on infusion lines has been controversial for many years, with strong advocates, detractors and many fence-sitting observers. The purpose of this review was to examine the literature for new developments and to cast the net a little wider than in previous reviews in an attempt to draw useful parallels.

RECENT FINDINGS

There were recent major policy statements or recommendations from a working party of the British Pharmaceutical Nutrition Group and from the US Centres for Disease Control. The first was focussed on filters and was broadly in favour, the second was not focussed on the subject but made quite a strong statement against, on microbiological issues alone. The major purpose of filters, however, is particulate contamination, and whilst there was little in the literature directly on this subject, useful parallels could be drawn from papers describing the therapeutic use of particles and also from their effects in intravenous drug users.

SUMMARY

When all the available information is considered, and the role of filters in particulate contamination, in-line chemical precipitates, identifying problems in parenteral therapy practice, microbial contamination and entrapped air is examined, the case for routine use appears strong.

Prospective comparison and 1-year follow-up of a single endoscopic subureteral polydimethylsiloxane versus dextranomer/hyaluronic acid copolymer injection for treatment of vesicoureteral reflux in children

OBJECTIVES

To compare, in a prospective study, the efficacy of a single injection of polydimethylsiloxane (Macroplastique) or dextranomer/hyaluronic acid copolymer (Deflux), a new biodegradable substance, and to assess the short-term and 1-year clinical effects concerning reflux resolution and the safety of these two bulking agents. Subureteral injection of bulking agents has recently demonstrated good success rates for endoscopic treatment of vesicoureteral reflux. Macroplastique has been one of the most popular bulking agents during the past years. Nevertheless, considering the synthetic property, new biodegradable substances have become more relevant.

METHODS

From January 2000 to June 2001, 16 boys and 56 girls (total of 114 ureters) with a mean age of 34.5 months were treated endoscopically for vesicoureteral reflux. A single subureteral Macroplastique or Deflux injection was performed in 34 children (58 ureters) and 38 children (56 ureters), respectively. Both groups were comparable in terms of baseline parameters. Vesicoureteral reflux was grade II in 52, grade III in 57, and grade IV in 5 ureterorenal units. The procedure was performed on an outpatient basis, with the children under general anesthesia. In addition to the routine parameters, the follow-up evaluation consisted of renal ultrasonography and voiding cystourethrography at 3 and 12 months postoperatively.

RESULTS

Endoscopic treatment was performed without any complications in all cases. At the 3-month follow-up visit, reflux was corrected in 50 (86.2%) of 58 refluxing ureters in the Macroplastique group and in 40 (71.4%) of 56 refluxing ureters in the Deflux group. At 1 year of follow-up, reflux correction was maintained in 80.9% of ureters in the Macroplastique group and in 67.6% of ureters in the Deflux group. No postoperative complications were observed in either group.

CONCLUSIONS

A single subureteral injection of either polydimethylsiloxane (Macroplastique) or dextranomer/hyaluronic acid copolymer (Deflux) is an effective treatment modality for children with vesicoureteral reflux. The procedure was well tolerated, safe, and associated with low morbidity. Deflux, a new biocompatible, biodegradable substance, seems to be an alternative modality to other bulking agents for treating vesicoureteral reflux in children, with acceptable short-term and 1-year results.

Pubovaginal slings: a review of the technical variables

The pubovaginal sling, reintroduced in the late 1970s by Maguire and Blaivas, has become the gold standard for managing anatomic incontinence. Newer technology, materials, surgical techniques and even new theories on the mechanism of action are evolving to further reduce the morbidity of these procedures and improve patient satisfaction. In the following review, we will highlight some of the exciting advances we have witnessed over the last year and try to put them into perspective for the reader.