Endoscopic injection of glutaraldehyde cross-linked bovine dermal collagen for correction of vesicoureteral reflux

Extravesical Ureteral Reimplantation Following Lich-Gregoir Technique for the Correction of Vesico-Ureteral Reflux Retrospective Comparative Study Open vs. Laparoscopy

Introduction: The aim is to compare the outcome of open versus laparoscopic Lich-Gregoir technique in patients with vesicoureteral reflux. We report a retrospective multicenter comparative study between open and laparoscopic extra-vesical ureteral reimplantation (EVUR) following Lich-Gregoir (LG) technique for the correction of Vesico-Ureteral Reflux (VUR). Materials and Methods: Between January 2007 and December 2015, 96 patients with VUR (69 females and 27 males) and deterioration of the renal function, underwent EVUR following LG technique. Fifty patients (16 males and 34 females) were operated by open surgery (group A). The mean age was 4.22 years-old, (14-147 months). Laparoscopic approach (group B) was performed in 46 patients (11 males and 35 females). The mean age was 4.19 years-old (15-110 months). We compared the results in relation to degree of VUR, operative time, hospital stay, post-operative pain medications, recovery time, complications, successful rate, recurrence, and follow-up. Statistical analysis was done used Chi square test for categorical variables and the Student t-test for continuous variables. P < 0.05 was considered significant. Results: In both groups no correlation was identified between age or weight and operative time, length of stay or total analgesia used. The mean operative time for group A was 63.2 and 125.4 min for unilateral and bilateral VUR, respectively, and for the group B was 127.90 and 184.5 min, respectively. There was no conversion in the laparoscopic group. Perioperative mucosal perforation of the bladder occurred in 6 patients of group A and 4 patients of group B and was immediately repaired. One patient had to be reoperated for leakage in group B. The mean duration of Morphine, IV and PO analgesia was shorter in group B. The mean hospital stay was 5.46 days for group A and 1.54 days for Group B. The success rate was 98% in group A and 97, 8% in group B. The mean follow-up was 3.67 years for the open and 1.54 years for the laparoscopic group. Transitory voiding dysfunction occurred in bilateral EVUR in one case in each group. Conclusion: Laparoscopic or Open approach for the correction of VUR following Lich-Gregoir technique is effective in unilateral and bilateral VUR with similar results. Laparoscopic approach reduces significantly (p < 0.05 in each item) post-operative pain medication, hospital stay, and allows for a faster return to normal activity.

[Primary vesicoureteral reflux]

The never ending discussion about the diagnostics and treatment of vesicoureteral reflux (VUR) now includes arguments for diagnostic nihilism as well as invasive diagnostics and therapy, which is reminiscent of the debate on prostate cancer in adulthood. The common goal of all currently competing diagnostic strategies and approaches is the prevention of renal scars by the most effective and least burdensome approach. There is a difference between acquired pyelonephritic scars with VUR (acquired reflux nephropathy) and congenital reflux nephropathy (primary dysplasia) which cannot be influenced by any therapy.The VUR can be verified by conventional radiological voiding cystourethrography (VCUG), by urosonography, radionuclide cystography or even by magnetic resonance imaging (MRI). The guidelines of the European Association of Urology/European Society for Paediatric Urology (EAU/ESPU) recommend radiological screening for VUR after the first febrile urinary tract infection. Significant risk factors in patients with VUR are recurrent urinary tract infections (UTI) and parenchymal scarring and the patients should undergo patient and risk-adapted therapy. Infants with dilating reflux have a higher risk of renal scarring than those without dilatation of the renal pelvis. Bladder dysfunction or dysfunctional elimination syndrome represents a well-known but previously neglected risk factor in combination with VUR and should be treated prior to any surgical intervention as far as is possible.Certainly not every patient with VUR needs therapy. The current treatment strategies take into account age and gender, the presence of dysplastic or pyelonephritic renal scars, the clinical symptoms, bladder dysfunction and frequency and severity of recurrent UTI as criteria for the therapy decision. The use of an antibacterial prophylaxis as well as the duration is controversially discussed. Endoscopic therapy can be a good alternative to antibacterial prophylaxis or a surveillance strategy in patients with low grade VUR. In patients with dilating VUR and given indications for surgery, endoscopic treatment can be offered. However, parents should be completely informed about the significantly lower success rate of endoscopic therapy compared to open surgical procedures. The open surgical techniques guarantee the highest success rates and should be used in patients with a dilating VUR and high risk of renal damage.

Laparoscopic extravesical transperitoneal approach following the lich-gregoir procedure in refluxing duplicated collecting systems: initial experience

INTRODUCTION

Vesicoureteral reflux (VUR) represents one of the most significant risk factors for acute pyelonephritis in children. Nephropathy with renal scarring is still the most concerning issue in VUR. Surgical correction to eliminate VUR is an important part of its management and this need is increasing for duplicated collecting systems (DCS). Laparoscopy may have a place in the treatment of VUR. We report our initial experience in the treatment of refluxing DCS by laparoscopic extravesical transperitoneal approach (LETA) following Lich-Gregoir technique. The aim of this study was to describe the evolution and evaluate the results and benefits of this technique.

MATERIALS AND METHODS

Between August 2007 and January 2010, 60 renal units in 43 children with VUR and deterioration of renal function on isotope renography were treated with LETA following the Lich-Gregoir procedure. Twelve patients had refluxing DCS in a lower polar system; three of them had bilateral VUR. Three cases of refluxing DCS were associated to obstruction. Two of them presented an ectopic ureterocele with adequate split renal function and another had an ectopic ureterocele with complete deterioration of upper polar renal function. Their mean age was 36 months (range: 15-80 months).

RESULTS

The mean surgical time was 90 minutes (38-140 minutes) in unilateral and 144 minutes (120-200 minutes) in bilateral VUR including cystoscopy. All procedures were successfully completed laparoscopically and the reflux was corrected in all patients. One-stage laparoscopic heminephroureterectomy with excision of ureterocele and ureteric reimplantation was done in 1 case, and ureterocele excision and ureteric reimplantation by LETA were done in 2 cases. The mean hospital stay was 27 hours. A cystogram was performed systematically in all patients at 45 days postoperatively; none of them presented recurrence of VUR. The follow-up period was 11 months (range: 2-24 months), without recurrence of VUR.

CONCLUSION

LETA following the Lich-Gregoir procedure in refluxing DCS is a safe and effective approach even in unilateral, bilateral simultaneous, and split renal function in duplicated systems. When refluxing DCS is associated with obstruction and total deterioration of upper polar function, heminephroureterectomy with excision of ureterocele and ureteric reimplantation can be safely and effectively performed in a single-stage laparoscopic procedure, which minimizes the hazards of traditional open surgical reconstruction. A shorter hospital stay, decreased postoperative discomfort, reduced recovery period, and a low morbidity to resolve VUR in DCS are the benefits of this technique, with success rates similar to the open technique.

Laparoscopic extravesical transperitoneal approach following the Lich-Gregoir technique in the treatment of vesicoureteral reflux in children

INTRODUCTION

Laparoscopy may have a place in the treatment of vesicoureteral reflux (VUR). We report our initial experience in the treatment of VUR by laparoscopic extravesical transperitoneal approach (LETA) following the Lich-Gregoir technique to describe the evolution and to evaluate the results and benefits of this technique for these patients.

MATERIALS AND METHODS

Between August 2007 and May 2009, 43 renal units in 30 children (23 female and 7 male) with VUR and deterioration of renal function on isotope renography (17 unilateral and 13 bilateral) were treated with LETA. The mean age was 52 (range, 15-183) months. Nine patients had a double total collector system associated with VUR in a lower system. Two of them had a ureterocele with adequate upper polar rein function, and another had a ureterocele with complete deterioration of upper polar rein function.

RESULTS

The mean surgical time was 70 (38-120) minutes in unilateral and 124 (100-180) minutes in bilateral VUR. All procedures were successfully completed laparoscopically, and the reflux was corrected in all patients. At the same time, 1 heminephrectomy and 2 ureterocele were removed by laparoscopy and endoscopy, respectively. We had 1 ureter leakage 15 days postoperation that underwent a redo reimplantation. In cases of bilateral VUR, 1 patient presented postoperative bladder emptying difficulty and required temporary urethral catheterization postoperatively. The mean hospital stay was 24 hours. A cystogram was performed systematically in all patients at 45 days postoperation; none of them presented recurrence of VUR. The follow-up was 11 (range, 2-24) months, without recurrence of VUR.

CONCLUSION

Laparoscopic extravesical transperitoneal approach in the treatment of VUR is a safe and effective approach even in unilateral, bilateral simultaneous, and double total collector system. The technique results in a shorter hospital stay, less postoperative discomfort, and reduced recovery period, with a low morbidity to resolve the VUR and with success rates similar to the open technique.

The clinical utility and safety of the endoscopic treatment of vesicoureteral reflux in patients with duplex ureters

OBJECTIVE

A systemic review of published literature on the use of bulking agents in the treatment of vesicoureteral reflux (VUR) in patients with duplex systems was performed in order to evaluate the diagnostic challenges; determine success rates, and compare with use in single systems; and evaluate safety, in particular of Deflux.

METHODS

A PubMed/Medline search was conducted for index articles discussing duplex ureters published in 1963-2007. All types of publications were included. A multiple linear regression analysis was performed.

RESULTS

Overall, 28 different treatment arms originating in 17 separate studies (19 publications) satisfied the inclusion criteria for linear regression efficacy analysis. Data were available on 2879 patients: 2400 with single and 479 with duplex systems. Ten publications provided information on the frequency of failure to diagnose duplex systems using specific techniques. An overall 18% failure rate to detect duplex systems was reported for combined techniques. For patients in whom favorable anatomic location of ureters allowed successful endoscopic injection of a bulking agent, correction of VUR was achieved in 53-100% of cases. A univariant analysis showed no difference in success rate between single and duplex systems with the use of Deflux, or other bulking agent. The predicted probability of success in a single system was 68% and in a duplex system 64%.

CONCLUSIONS

There is significant potential for failing to detect duplex systems prior to preparing an individual for either open or endoscopic treatment. From the studies available, endoscopic injection of bulking agents is highly successful in correcting mild-to-moderate VUR in duplex systems, with no reports of serious or clinically significant adverse effects. At a minimum, duplex systems would not seem to be a contraindication to the use of Deflux or any other bulking agent.

Use of collagen for endoscopic correction in complicated vesicoureteral reflux

OBJECTIVE

Endoscopic treatment of children with primary vesicoureteral reflux (VUR) has become an alternative to long-term antibiotic prophylaxis and open surgery. The purpose of this study was to assess the efficiency and safety of endoscopic subureteral injections of collagen (STING) as a treatment for complicated VUR in children.

MATERIAL AND METHODS

Twenty-five patients (41 ureteral units) underwent a modified STING procedure for the correction of complicated VUR. Of these patients, five (nine refluxing units) had Hutch's diverticulum, 10 (17 refluxing units) had a duplex system, eight (10 refluxing units) had ureterocele, one (three refluxing units) had a unilateral triple ureter and one (two refluxing units) had a bilateral single ectopic ureter. Of these 41 ureteral units, 14 had grade III VUR, 17 grade IV and 10 grade V. Fourteen refluxing units (30%) received one session of STING, which was successful, and 27 (70%) needed a second session. A follow-up voiding cystourethrogram was performed 3 months after each session of STING.

RESULTS

The mean follow-up period was 24 months (range 3-36 months). Of these 41 refluxing units, 34 were treated successfully and regression or downgrading occurred in seven. Follow-up i.v. pyelography or sonography did not reveal any urinary tract obstruction.

CONCLUSIONS

The results of this study showed that endoscopic correction of these complicated refluxing ureters may be the first choice of treatment, but the technique must be modified to suit each individual case.

The effect of microsphere degradation rate on the efficacy of polymeric microspheres as bulking agents: An 18-month follow-up study

The injection of bulking substances has been proposed as a new therapy to treat urinary incontinence and vesicoureteral reflux. Our previous study demonstrated that poly(lactic-co-glycolic acid) (PLGA) microspheres have the potential to serve as a bulking agent for urological injection therapies. Hybrid tissues exhibiting a bulking effect were formed in vivo by PLGA microsphere injection, but long-term volume stability was not proven. In this study, we hypothesized that the biodegradation rate of the bulking substance (polymer microspheres) would affect the duration of volume conservation of the induced hybrid tissue. To test this hypothesis, rapidly degrading 75:25 PLGA microspheres and slowly degrading poly(L-lactic acid) (PLLA) microspheres were used as injectable bulking agents for the injection therapy. In vitro degradation tests showed that the mass losses of PLLA and PLGA were 16 and 96% of the initial masses, respectively, at 30 weeks. PLLA and PLGA microspheres were injected into the subcutaneous dorsum of mice. Both types of microspheres were easily injectable through 24-gauge needles. Histological examinations at various time points indicated that host cells from the surrounding tissues migrated to the spaces between both types of injected microspheres and formed new hybrid tissue structures. Lymphocyte migration was noted around the implanted PLGA and PLLA microspheres, but the inflammatory reaction diminished with time. Importantly, the volume of the PLLA hybrid tissues slowly decreased to 52% of the initial volume at 12 months and maintained that volume until 18 months, whereas the volume of the PLGA hybrid tissues rapidly decreased to 22% at 6 months, and the PLGA hybrid tissues disappeared at 11 months. These results show that the biodegradation rate of the bulking substance may be useful for controlling the duration of volume conservation of the induced hybrid tissue.

Submucosal injection of poly(lactic-co-glycolic acid) microspheres in rabbit bladder as a potential treatment for urinary incontinence and vesicoureteral reflux: preliminary results

Endoscopic injection of bulking agents has been gaining attention as a therapy for urinary incontinence and vesicoureteral reflux because this therapy is simpler, less operation time-consuming and less painful than traditional surgical operations. The ideal bulking agent for the injection therapies must be easily injectable, biocompatible, volume-stable, non-antigenic and non-migratory. We evaluated poly(lactic-co-glycolic acid) (PLGA) microspheres as an injectable bulking agent for urologic injection therapies. To determine whether PLGA microspheres meet the requirements of an ideal bulking agent, PLGA microspheres were injected into the submucosal sites of a rabbit bladder wall. The microspheres were easily injectable. Two and five weeks post-implantation, histological examinations indicated that host cells from the surrounding bladder tissues migrated to the space between the injected microspheres and formed new hybrid tissue structures. Lymphocyte migration was noted around the implanted microspheres, but the inflammatory reaction diminished at 5 weeks. The hybrid tissue volume did not significantly decrease over time. There was no evidence of microsphere migration to the distant organs. Although long-term studies are needed to evaluate the therapeutic potential of this method, these preliminary results suggest the possibility of PLGA microspheres as a potentially useful injection material for urinary injection therapies.

Role of periureteral injections in children with vesicoureteral reflux

PURPOSE OF REVIEW

Periureteral injection has become an increasingly popular method for managing vesicoureteral reflux in children. This minimally invasive and seemingly effective technique, completed in a simple manner, is attracting more attention from urologists and parents alike. This review describes the contemporary experience with injection therapy and attempts to define its place in the algorithm for the management of vesicoureteral reflux.

RECENT FINDINGS

A variety of different substances have been tried as bulking agents to eliminate vesicoureteral reflux since the technique was introduced more than 20 years ago. Long-term follow-up has found drawbacks with each substance tried. Dextranomer polysaccharide microspheres crosslinked in sodium hyaluronan (Deflux; Ixion Biotechnology, Inc, Alachua, Florida, USA) have recently appeared as another alternative in treatment. Recent reports have focused on the efficacy of the material used in patients with different grades of reflux and in patients whose reflux is associated with other conditions. The substance has performed reasonably well in most initial studies but its cure rates do not approximate those of open surgery. Technical improvements and risk factors for failure are gradually being identified that are aimed at improving performance. The long-term efficacy of Deflux is not well defined and cost-analysis data of patients managed in a prospective randomized fashion are lacking.

SUMMARY

The role of periureteral injection therapy, for patients whose vesicoureteral reflux requires correction, remains unclear. Further studies are needed to elucidate its place in the algorithm for the management of this common problem in children.

[Primary vesicoureteral reflux treatment in childhood: comparsion of two systematic review]

Many medical practices are being carried out unawares of their efficiency, or of their actual impact on the health of the patients, therefore it is necessary to consider the support of professional recommendations with scientific evidence.

THE PRIMARY OBJECTIVE

To perform a systematic review (SR) of the therapeutic management of primary VUR in pediatric urology.

MATERIAL AND METHODS

A systematic review has been performed, including scientific evidence-based medicine criteria, of the articles published in all of the available databases. Inclusion criteria concerning basic quality of the articles were considered essential, as well as exclusion criteria to be able to reject the articles.

RESULTS AND DISCUSSION

Subsequently, and following the critic reading of greater than 320 articles, statistical study of the grouped data was performed according to the type of treatment and to the benefits contributed by each treatment, and also to their undesirable effects. Finally we have made a comparison between our results and recent Cochrane Systematic Review. The following Conclusions were drawn from the results obtained and from the analysis of the texts. Both medical and surgical treatment present with similar effectiveness concerning resolution of grades I, II and III of VUR, and the former one is the recommended initial treatment following diagnosis. Endoscopic treatment is exactly as effective as open surgery for grades I, II and III with fewer undesirable effects secondary. There are no differences concerning the efficacy of the different injected substances. Not enough evidences exist for degrees IV and V that may recommend or advise against any of the treatments. In any degree of VUR, open surgical treatment is superior as far as medical treatment is concerned only regarding the number of acute pyelonephritis episodes during followup. This conclusion cannot be applied on endoscopic treatment.

Does deflux alter the paradigm for the management of children with vesicoureteral reflux?

The recent approval by the US Food and Drug Administration of Deflux (Q Med, Uppsala, Sweden), a particulate biodegradable polymer of dextran, has led to an understandable enthusiasm for treating children with vesicoureteral reflux by a routinely simple outpatient endoscopic procedure. However, Deflux is but one of a variety of particulate substances, both permanent and absorbable, that have been used to treat reflux in Europe for well over a decade with varying degrees of success. The purpose of this review is to place Deflux in this wider context to anticipate what can be expected realistically regarding the efficacy and potential hazards of this seductive technique and to make recommendations regarding its incorporation, in selected cases, in our therapeutic armamentarium.

Long-term outcome of the endoscopic correction of vesico-ureteric reflux: a comparison of injected substances

OBJECTIVE

To summarize the long-term outcome of endoscopic surgery to correct vesico-ureteric reflux (VUR) using different injected substances, i.e. autologous blood, hyaluronan/dextranomer copolymer (HDC), PTFE and glutaraldehyde cross-linked bovine dermal (GAX) collagen.

PATIENTS AND METHODS

Treatment results on 270 ureters of 185 patients followed for >5 years (mean 8.5) were summarized according to the injected substances. The substances were injected into the 6 o'clock position of the ureteric orifice endoscopically. "Success" was defined as the absence of VUR for >5 years after a single injection.

RESULTS

The treatment was successful in two of 24 patients (8%) with autologous blood, 17 of 32 (53%) with HDC, 108 of 171 (63%) with PTFE and 24 of 43 (56%) with GAX collagen. The success rate was lower in patients with higher grades of VUR.

CONCLUSIONS

Autologous blood is unsuitable for clinical application because of its poor durability. We will no longer use PTFE because its safety is not well established. The overall success rates of endoscopic surgery with GAX collagen and HDC were insufficient compared with surgical reimplantation, but it is advantageous that this procedure is less invasive and can be repeated. The cure rate could be improved by excluding high-grade VUR from the indications for endoscopic surgery.

Cystoscopic correction of reflux

Vesicoureteral reflux is a well-recognized cause of childhood illness and renal damage. In the past, surgical reimplantation had been the only procedure available to gain the immediate cessation of reflux. The development of an endoscopic injection technique as a less morbid alternative to traditional surgery began in the 1980s. Teflon was the first injectable agent to be investigated. The record of Teflon is one of efficacy and apparent patient tolerance. However, concerns regarding possible migration and other side effects led to a search for other injectable agents. The most recently investigated agents are polydimethylsiloxane and dextranomer polymer. These agents do not have the long-term follow-up of Teflon, but appear to be effective and safe. Time will tell which agent will become the implant of choice, but it seems clear that endoscopic management will play an increasingly larger role in the care of vesicoureteral reflux.

Ureteral reimplantation for vesicoureteral reflux: comparison of minimally invasive extravesical with transvesical and conventional extravesical techniques

OBJECTIVES

To analyze and compare the different ureteral reimplantation techniques to clarify the decision making for surgical treatment of vesicoureteral reflux.

METHODS

From July 1995 to December 2000, 218 patients underwent antireflux surgery. The first 92 cases (143 ureters) were performed with the transvesical technique of Cohen (group 1), the next 37 cases (49 ureters) with the conventional extravesical technique (group 2), and the last 89 cases (113 ureters) with the new minimally invasive technique (group 3). The surgical time, length of hospital stay, postoperative side effects, frequency of pain control, and voiding cystogram findings to ensure the cessation of reflux for all patients were retrospectively analyzed.

RESULTS

The success rates were similar among the different procedures. All patients in group 1 required a suprapubic cystostomy, and three had blood clot retention. Four patients in group 2 had bladder inefficiency. The surgical time ranged from 139 to 181 minutes in group 1, 58 to 94 minutes in group 2, and 40 to 61 minutes in group 3. The length of hospital stay ranged from 2.8 to 5.5 days in groups 1 and 2, and no hospital stay was needed in group 3. The frequency of analgesic administration was significantly less in group 2 compared with group 1; however, no analgesia was required in group 3.

CONCLUSIONS

The results from our comparison show that the minimally invasive technique can be used as a simple and highly effective interventional procedure with less morbidity for the patient.

Poly(lactic-co-glycolic acid) microspheres as a potential bulking agent for urological injection therapy: Preliminary results

Injection of bulking substances has been introduced as a new therapy to treat urinary incontinence and vesicoureteral reflux. Currently available bulking substances for the injection therapies include liquid or particulated silicone, collagen gel, and polytetrafluoroethylene paste. However, these materials have shown shortcomings such as inflammation, rapid volume decrease, and particle migration to distant organs. In the present study, we evaluated poly(lactic-co-glycolic acid) (PLGA) microspheres as a potential injectable bulking agent for the injection therapies. PLGA microspheres (52 microm in average diameter) were injectable through various gauges of needles, as the injected microspheres showed no tendency to obstruct the needles and microsphere size exclusion was not observed upon injection through the needles. After injection of PLGA microspheres into the subcutaneous dorsum of mice, inflammation, new tissue volume change, and microsphere migration were examined. Host cells from the surrounding tissues migrated to the implanted microspheres and formed new hybrid tissue structures. The volume of the newly generated tissues was maintained approximately constant for 7 weeks. Histological analyses showed no evidence of migration of the implanted microspheres to the distant organs. In summary, PLGA microspheres were injectable and able to induce a new hybrid tissue formation without initial volume decrease or particle migration. These preliminary results suggest that this material may be a potentially useful bulking agent for urological injection therapies.

Use of collagen injections for vesicoureteral reflux in transplanted kidneys

Reports in the literature suggest the incidence of vesicoureteral reflux (VUR) in transplanted kidneys to range from 2-79%. Collagen injections have been used with reported success rates of up to 65% to prevent VUR into native orifices in children, but have not been studied in transplant neo-orifices. We evaluated the use of collagen injections in seven patients with transplant kidney neo-orifices who displayed grades II-IV VUR and seemed to be related to symptomatic urinary tract infections (UTIs). Postoperative VCUGs obtained at 2 months showed improvement in the grade of reflux in four of seven (57.1%) patients; one (14.3%), no change; and two (28.6%), worse reflux. All patients also redeveloped symptomatic UTIs after collagen injection. We conclude that the use of collagen injections in kidney transplant neo-orifices did not prevent VUR. Although prevention of VUR may have been achieved short term, VCUG examinations 2 months after initial injection revealed persistent reflux. Etiologies for failure to prevent VUR may be the readily absorbable nature of collagen, technical aspects of the procedure, the degree of reflux, and anatomic differences between native orifices (which lie on a well-supported trigone) and transplant neo-orifices (which lie on the posterior wall with less support).

The history and future of implantation therapy for gastroesophageal reflux disease

The initial development of endoscopic implantation techniques for the treatment of gastroesophageal reflux disease in the 1980s helped set the stage for current implantation techniques and studies, which now include more than 500 patients. The relative simplicity of these techniques adds to their attraction. Ultimately, multiple factors, including therapeutic efficacy durability, safety, simplicity, and cost-effectiveness, will determine clinical application of these techniques. This article focuses on transoral endoscopic implantation, although surgical, transcutaneous, and other endoscopic routes have been used as well.

Subureteral polydimethylsiloxane injection versus extravesical reimplantation for primary low grade vesicoureteral reflux in children: a comparative study

PURPOSE

We compare the outcome of extravesical ureteral reimplantation to endoscopic polydimethylsiloxane (Macroplastique, Uroplasty, Inc., Minneapolis, Minnesota) subureteral injection for primary low grade vesicoureteral reflux in children.

MATERIALS AND METHODS

Between 1997 and 2000, 180 patients underwent polydimethylsiloxane injection (74, 108 ureters) or extravesical ureteral reimplantation (106, 166 ureters) for low grade vesicoureteral reflux. Low grade reflux was defined as grades I to III. Outcome analysis included success rates, de novo hydronephrosis, voiding efficiency, urinary tract infections and complications.

RESULTS

Mean patient age at surgery for the injection and surgery groups was 60 and 77 months, and mean followup was 12 and 15 months, respectively. Of the patients who underwent single injection 80.6% were cured of reflux at 3 months and 91.6% were cured at last followup. Success rate after reimplantation was 95.8% at 3 months which improved to 98.8% 1 year later. The success rate was significantly different between the injection and reimplantation groups at 3 and 12 months (p <0.01). Postoperative complications in the reimplantation group included transient urinary retention after bilateral surgery in 2 patients (3.3%), suprapubic fluid collections in 2 and wound seroma in 1. No complications occurred in the polydimethylsiloxane group.

CONCLUSIONS

Extravesical ureteral reimplantation has near perfect success with a low but definite complication rate. Polydimethylsiloxane offers high success rates for reflux in an ambulatory setting with no short-term complications. Currently, endoscopic polydimethylsiloxane injection is our preferred mode of therapy for low grade vesicoureteral reflux in children when surgical correction is indicated.

Endoscopic injection therapy for treatment of vesicoureteric reflux: A 20-year perspective

OBJECTIVE

To review the application and outcome of endoscopic injection therapy for vesicoureteric reflux in regard to its evolution over the past two decades.

DATA SOURCES

Review articles, original reports and abstracts pertaining to endoscopic injection therapy were obtained through a PubMed search of English, German and French publications from 1981 to 2001.

DATA SELECTION

A total of 46 studies were selected. Four were selected to support basic concepts in the management of vesicoureteric reflux, and the remainder pertained specifically to endoscopic injection therapy for vesicoureteric reflux.

DATA EXTRACTION

The reports were analyzed with focus on the physical properties of the biomaterial injected, results of treatment in regard to the cure of vesicoureteric reflux, duration of cure, and possible adverse effects and clinical benefits engendered by the use of injectable materials.

DATA SYNTHESIS

Endoscopic injection therapy successfully cures vesicoureteric reflux in 60% to 80% of cases. Success rates are higher with particulate materials (Teflon and Macroplastique) than with bovine collagen or autologous chondrocytes. Long term data regarding cure are scant. Although concerns about particulate migration and autoimmune disease exist, these have not been borne out of clinical experience. Endoscopic injection may be accomplished on an outpatient basis, with less morbidity than with open ureteroneocystostomy.

CONCLUSIONS

Endoscopic injection therapy should be offered as an alternative treatment in patients with indications to consider ureteroneocystotomy, but should not change the indications for surgical intervention. The ideal biomaterial for injection has yet to be developed, but the field of autologous tissue engineering holds promise for future development.

Long-term results of the endoscopic correction of vesicoureteral reflux in children using autologous chondrocytes

PURPOSE

Endoscopic correction of vesicoureteral reflux continues to attract research of many autologous and nonautologous substances. We previously reported on the initial results of a clinical trial using endoscopic injection of autologous chondrocytes to correct vesicoureteral reflux in children and now present our greater than 1-year followup results.

MATERIALS AND METHODS

A total of 29 children (47 ureters) with grades II to IV vesicoureteral reflux were treated at 2 centers. Each child underwent cystoscopy and posterior auricular cartilage harvesting at the initial setting. Chondrocytes were grown in culture during a 6-week period. Patients returned for transurethral injection of autologous chondrocytes into the ureterovesical junction of the refluxing ureters. Ultrasound was performed at 1 month, 1 year, and 2 and 3 years after implantation, and a voiding cystourethrogram or radionuclide cystogram at 3 months and 1 year after injection. If reflux persisted re-treatment with stored chondrocytes was offered.

RESULTS

At 3-month followup initial chondrocyte injection corrected reflux in 55% of ureters (27 of 47) while a second or third injection was successful in additional 15 of 29 patients, resulting in an overall success rate of 86% (42 of 49) ureters and 25 of 29 patients. At 1-year followup reflux correction was maintained in 70% of ureters (32 of 46) and 65% of patients (19 of 29). The 1-year followup results after re-treatment of 3 ureters were not available. In those patients in whom implantation failed cystoscopy revealed evidence of volume loss and shifting of subureteral mounds to account for loss of the antireflux effect. Three patients underwent successful open ureteroneocystostomy for failed autologous chondrocyte implantation. There were no significant complications.

CONCLUSIONS

Transurethral injection of autologous chondrocytes to correct vesicoureteral reflux in children is safe and reasonably effective. There is a relapse rate which must be considered. Changes in the formulation of the material have been made to enhance implant reliability and increase long-term success.

Long-term results of the endoscopic correction of vesicoureteral reflux in children using autologous chondrocytes

PURPOSE

Endoscopic correction of vesicoureteral reflux continues to attract research of many autologous and nonautologous substances. We previously reported on the initial results of a clinical trial using endoscopic injection of autologous chondrocytes to correct vesicoureteral reflux in children and now present our greater than 1-year followup results.

MATERIALS AND METHODS

A total of 29 children (47 ureters) with grades II to IV vesicoureteral reflux were treated at 2 centers. Each child underwent cystoscopy and posterior auricular cartilage harvesting at the initial setting. Chondrocytes were grown in culture during a 6-week period. Patients returned for transurethral injection of autologous chondrocytes into the ureterovesical junction of the refluxing ureters. Ultrasound was performed at 1 month, 1 year, and 2 and 3 years after implantation, and a voiding cystourethrogram or radionuclide cystogram at 3 months and 1 year after injection. If reflux persisted re-treatment with stored chondrocytes was offered.

RESULTS

At 3-month followup initial chondrocyte injection corrected reflux in 55% of ureters (27 of 47) while a second or third injection was successful in additional 15 of 29 patients, resulting in an overall success rate of 86% (42 of 49) ureters and 25 of 29 patients. At 1-year followup reflux correction was maintained in 70% of ureters (32 of 46) and 65% of patients (19 of 29). The 1-year followup results after re-treatment of 3 ureters were not available. In those patients in whom implantation failed cystoscopy revealed evidence of volume loss and shifting of subureteral mounds to account for loss of the antireflux effect. Three patients underwent successful open ureteroneocystostomy for failed autologous chondrocyte implantation. There were no significant complications.

CONCLUSIONS

Transurethral injection of autologous chondrocytes to correct vesicoureteral reflux in children is safe and reasonably effective. There is a relapse rate which must be considered. Changes in the formulation of the material have been made to enhance implant reliability and increase long-term success.

Evaluation of antibody class in response to endoscopic subureteral collagen injection in patients with vesicoureteral reflux

PURPOSE

Clinical problems after glutaraldehyde cross-linked collagen injection for vesicoureteral reflux are the appearance of anticollagen antibodies and a decrease in collagen with time. We evaluated whether antibody production affects reflux recurrence and implanted collagen absorption.

MATERIALS AND METHODS

We treated 27 patients (39 ureters) who had vesicoureteral reflux with endoscopic subureteral glutaraldehyde cross-linked collagen injection. The maximum diameter of the elevated ureteral orifice was measured 3-dimensionally and the numerical value calculated by multiplying each diameter by approximately pi/6 was used as the ultrasound estimate of injected collagen volume. The 1-to-6-month collagen volume ratio was used as an index of the decrease in implant collagen volume. The antibody class against bovine collagen was characterized by indirect enzyme-linked immunosorbent assay.

RESULTS

Seroconversion in 6 patients was noted a mean 6.8 months after the first injection. In these patients the antibody class was IgG dominant and IgA or IgM was not detected. There was no significant difference in the total injected collagen volume, total number of injections or collagen volume ratio in the seropositive and seronegative groups. Reflux recurred in 4 patients and the curve of the reflux-free rate was similar regardless of antibody appearance.

CONCLUSIONS

The immune response to bovine collagen injection for vesicoureteral reflux does not depend on injected collagen volume or an increased number of treatments. Antibody production had no effects on absorption of the implanted collagen or reflux recurrence.

Failure of subureteral bovine collagen injection for the endoscopic treatment of primary vesicoureteral reflux in long-term follow-up

OBJECTIVES

To evaluate the long-term efficacy of subureteral glutaraldehyde cross-linked collagen injection (GAX 35) for endoscopic treatment of primary vesicoureteral reflux (VUR).

METHODS

We prospectively studied 36 patients (58 ureteral renal units), 30 girls and 6 boys with a median age of 6 years (range 2 months to 18 years). All patients had primary VUR and were treated with a single subureteral collagen injection (GAX 35). The patients were followed up by voiding cystography.

RESULTS

According to the International Reflux Study Classification, we found the following reflux grades preoperatively: grade I, 2 ureteral units; grade II, 21 units; grade III, 28 units; grade IV, 4 units, and grade V, 3 units. All patients were treated with subureteral bovine collagen injection (GAX 35, mean volume 1.7 mL, range 0.7 to 3.5). All but 3 cases of reflux resolved initially. The mean follow-up was 13 months (range 1 to 108). After 37 months of follow-up, only 5 (9%) of 57 treated units remained reflux free. One unit was followed up for 17 months and also remained reflux free.

CONCLUSIONS

These data suggest that a single endoscopic subureteral collagen injection is not effective in the long-term follow-up of patients with primary VUR. In the future, it will be important to determine whether the new, currently used, and soon be approved bulking agents show better long-term clinical results to prevent VUR recurrence than bovine collagen does.

Laparoscopic bladder 'wrap' technique for repair of vesicoureteric reflux in a porcine model

PURPOSE

The aim of this study was to determine if vesicoureteric reflux (VUR) can be successfully corrected laparoscopically by a bladder "wrap" technique in a pig model.

METHODS

In 15 female piglets (mean weight, 22.5 kg) bilateral VUR was created by an open technique (11 grade 3, 2 each of grades 2 and 4). Eight weeks later (range, 4to 16 weeks) VUR was confirmed by fluoroscopic cystogram, and unilateral laparoscopic correction was performed. The contralateral ureter was used as a control. The bladder was emptied, and a 3F ureteric catheter was inserted on the repair side. Four 11-mm ports were inserted transperitoneally. The ureter was dissected to the ureterovesical junction (UVJ). Commencing at the UVJ, 2 (n = 9) or 3 (n = 6) black silk sutures were placed through the bladder muscle on either side of the ureter creating a bladder wrap around the distal 2 to 4 cm of ureter. At a mean of 16 weeks (range, 4 to 24 weeks) cystograms were repeated. The animals were killed the bladder and ureters underwent histopathology examination.

RESULTS

VUR was corrected in 12 animals (80%). There was persistence of VUR in 2 and ureteric obstruction in 1. The wrap was intact in all animals.

CONCLUSIONS

Laparoscopic correction of VUR by the bladder wrap technique is successful in pigs. Long-term follow-up studies will determine if this will be a satisfactory alternative surgical treatment for correction of VUR in children.

Endoscopic treatment of children with vesico-ureteric reflux

Endoscopic subureteric injection of tissue-augmenting substances has become an alternative to long-term antibiotic prophylaxis and open surgery in the treatment of children with vesico-ureteric reflux. Successful elimination of reflux in about 80% of patients after a single injection (and in 90% after a repeat) has been achieved using the foreign-body non-degradable substances Teflon and silicone. Few patients have required open surgery and recurrence of reflux after initial successful treatment has occurred in only 5-10%. Concern has arisen, however, about possible distant migration and granuloma formation after injection of particulate plastic materials. Cross-linked bovine collagen is a biodegradable alternative substance, but with a lower response rate of 60% after the first treatment and a recurrence rate of 10-20%. Dextranomer in sodium hyaluronan is a new biological substance with microparticles with a response rate of 69% after the first injection. Biological substances have caused few complications. Present literature on injection treatment unfortunately focuses on elimination of reflux, with little attention to subsequent frequency of pyelonephritis or to the long-term development of the kidneys. Furthermore, there are no controlled, randomized studies with subureteric injection as one of the treatment alternatives. Thus, although having the advantage of being a minimally invasive procedure that can be performed on an outpatient basis, this technique needs to be tested in a large prospective study with the long-term renal outcome as the main end-point.

Endoscopic correction of vesicoureteral reflux in children using autologous chondrocytes: preliminary results

PURPOSE

Previous approaches to the endoscopic correction of vesicoureteral reflux have used foreign bulking substances, raising concern regarding safety and long-term efficacy. We describe the results of a clinical trial using transurethral injection of autologous chondrocytes to correct vesicoureteral reflux in children.

MATERIALS AND METHODS

A total of 29 children (46 ureters) with grades II to IV vesicoureteral reflux were treated at 2 sites. Each child underwent cystoscopy and ear cartilage biopsy at the initial setting. Chondrocytes were grown in culture for 6 weeks. Patients then returned for transurethral injection of chondrocytes into the bladder trigone to correct reflux. Ultrasound was performed 1 month and radionuclide cystography was done 3 months postoperatively to confirm reflux resolution. When reflux persisted, repeat treatment with stored chondrocytes was offered.

RESULTS

Initial chondrocyte injection corrected reflux in 26 of the 46 ureters (57%), while secondary injection was successful in 12 of 19 (63%). Overall reflux was corrected in 38 of the 46 ureters (83%) and in 24 of the 29 patients (83%). There were no significant complications.

CONCLUSIONS

Transurethral injection of autologous chondrocytes to correct vesicoureteral reflux in children appears to be an effective and safe technique that holds promise for treating this congenital abnormality in a minimally invasive fashion.

Endoscopic correction of vesicoureteral reflux in children using autologous chondrocytes: preliminary results

PURPOSE

Previous approaches to the endoscopic correction of vesicoureteral reflux have used foreign bulking substances, raising concern regarding safety and long-term efficacy. We describe the results of a clinical trial using transurethral injection of autologous chondrocytes to correct vesicoureteral reflux in children.

MATERIALS AND METHODS

A total of 29 children (46 ureters) with grades II to IV vesicoureteral reflux were treated at 2 sites. Each child underwent cystoscopy and ear cartilage biopsy at the initial setting. Chondrocytes were grown in culture for 6 weeks. Patients then returned for transurethral injection of chondrocytes into the bladder trigone to correct reflux. Ultrasound was performed 1 month and radionuclide cystography was done 3 months postoperatively to confirm reflux resolution. When reflux persisted, repeat treatment with stored chondrocytes was offered.

RESULTS

Initial chondrocyte injection corrected reflux in 26 of the 46 ureters (57%), while secondary injection was successful in 12 of 19 (63%). Overall reflux was corrected in 38 of the 46 ureters (83%) and in 24 of the 29 patients (83%). There were no significant complications.

CONCLUSIONS

Transurethral injection of autologous chondrocytes to correct vesicoureteral reflux in children appears to be an effective and safe technique that holds promise for treating this congenital abnormality in a minimally invasive fashion.

Feasibility of total intravesical endoscopic surgery using mini-instruments in a porcine model

BACKGROUND AND OBJECTIVES

The aim of minimally invasive approaches to vesicoureteral reflux, such as endoscopic trigonoplasty, is to lower the morbidity of open procedures without compromising the results. Initial successes have not been sustained, mainly because of trigonal splitting, which results in the ureteral orifices returning to their preoperative positions. This study was designed to address trigonal splitting by mobilizing the ureters before repositioning them and to evaluate the feasibility of accomplishing this intravesically with 2- to 3-mm endoscopic mini-instruments.

METHODS

Bilateral vesicoureteral reflux was surgically created in 10 minipigs. After radiologic confirmation of success 4 weeks later, modified trigonoplasty was performed by endoscopic intravesical mobilization of both ureters and incision of the trigonal mucosa using 2-mm instruments. The ureteral orifices were then advanced toward the midline and sutured in place. The initial surgical techniques were modified to permit the entire procedure to be performed endoscopically in the last four minipigs. Cystograms and intravenous urograms were obtained 4 weeks later.

RESULTS

Two minipigs died postoperatively. Six of the remaining eight had persistent reflux, including three of the four in the group treated completely by endoscopic means. None of the dissected ureters showed evidence of stricture or necrosis.

CONCLUSIONS

Although the procedure was not successful in correcting reflux in this model, this study demonstrates the feasibility of endoscopic ureteral mobilization. With current instrumentation, there is no significant technical obstacle to complete intravesical endoscopic surgery, including ureteral reimplantation.

New advances in injectable therapies for the treatment of incontinence and vesicoureteral reflux

Clinical experience over the last two decades has demonstrated that the endoscopic correction of primary vesicoureteral reflux and urinary incontinence caused by intrinsic sphincteric dysfunction is both possible and effective. The ideal material for use in these regards has yet to be developed. As a result, there has been a continuing research effort directed towards the development of new injectable substances. Nonautologous substances, such as Teflon, collagen, and Deflux, and autologous substances such as fat, chondrocytes and muscle, have been used either clinically or are under investigation. Although the ideal substance has yet to be determined, many of the substances currently under development appear promising. The use of a particular substance may best be determined by the clinical circumstance involving each individual patient.

Tissue engineering in urologic surgery

The use of nonurologic tissues in the genitourinary tract is common (owing to a lack of a better alternative) despite the known possible adverse effects. Selective cell transplantation is providing a means to engineer genitourinary tissues that may be used for reconstruction. This novel technology involves an interdisciplinary approach, combining techniques of cell biology and materials sciences towards the development of functional tissues or organs. Tissues associated with urology, such as clitoral, cavernosal, urethral, vesical, ureteral, and renal have been created in the laboratory, with varying degrees of function. Cells have also been recently used in patients as bulking agents for the treatment of vesicoureteral reflux and urinary incontinence. As the science of tissue engineering evolves, one can expect a wider application of this technology to the armamentarium of urologic surgery.

Endoscopic treatment of vesicoureteral reflux in children

Endoscopic surgery for vesicoureteral reflux involves injection of a substance beneath the ureterovesical junction (UVJ) to buttress this region. In children, this procedure typically is performed under anesthesia on an outpatient basis, with minimal postoperative pain and a rapid recovery.

Endoscopic substances for the treatment of vesicoureteral reflux

The endoscopic treatment of reflux, like that of urinary incontinence, is effective. Several materials and endoscopic delivery systems are currently under evaluation for the treatment of reflux and incontinence. These include silicone microimplants, glass particles, collagen, dextranomer microspheres, a detachable balloon system, chondrocytes, and muscle cells. Although the endoscopic treatment is rendered in a similar fashion for both urinary incontinence and reflux, the acceptable safety and efficacy parameters of the bulking agents may differ, depending on the condition treated and the age of the patient. A review of the endoscopic bulking substances and systems currently available is presented.

Endoscopic treatment of reflux by subureteric collagen injection: critical review of 5 years' experience

In the past decade, subureteric endoscopic injection of Teflon or collagen has been propagated as a safe and successful treatment for vesicoureteral reflux. In our center, from 1990 through 1995, 118 children and 5 adults with reflux and recurrent urinary tract infections were injected with cross-linked bovine collagen in an open, prospective study. Efficacy and safety were assessed 6 and 12 months after injection, and long-term (> or =3 years) results were available in 78 cases. The overall success rate was 58% (64% of ureteral units) free from reflux at 12 months and 54% (58%) after 3 years. Analysis of anatomic, urodynamic, and technical features showed the grade of reflux to be the best predictor of success or failure. When only primary low- and middle-grade reflux, without concomitant anatomic disorders, is considered, the long-term success rate rose to 69% (74% of ureteral units). In conclusion, subureteric collagen injection cannot ultimately replace the highly effective surgical reimplantation. However, the procedure offers a minimally invasive alternative in selected cases of mild reflux when conservative management is inadequate.

Géis de colágeno aniônico: ransana como biomateriais. Preparação e caracterização físico-química

Este trabalho descreve o efeito da ransana, um polissacarídeo bacteriano, sobre géis de colágeno aniônico. A interação colágeno:ransana ocorreu independentemente do pH, mesmo com baixas concentrações de ransana, e os materiais obtidos no estado sólido foram caracterizados por serem mais estáveis térmicamente à medida em que se aumenta a concentração do polissacarídeo. Nenhuma alteração na estrutura secundária em tripla hélice do tropocolágeno foi observada. O efeito mais significativo da ransana sobre os géis aniônicos de colágeno foi um aumento significativo da viscosidade, e as variações observadas em função de pH e temperatura sugerem que nesta interação, não estão envolvidas forças de natureza eletrostática ou hidrofóbica. Micrografias de colágeno aniônico e colágeno aniônico:ransana mostraram a presença de estruturas vesiculares, diferente do padrão fibrilar característico de colágeno nativo. Um modelo de interação baseado na ação da ransana sobre a água estruturada, associada à organização macromolecular do colágeno em solução é proposto. Mais importante, géis de colágeno aniônico:ransana mostraram uma estabilidade térmica compatível com aquelas desejáveis para um biomaterial injetável de colágeno, evitando o uso do glutaraldeído como agente de estabilização.