Subureteral Injection Research Articles

Endoscopic correction of vesicoureteric reflux in infants under 2 years of age

Forty-seven infants under the age of 2 years with vesicoureteric reflux were treated by subureteric injection of Polytef paste; 4 have completed sufficient follow-up to be analysed. The 41 patients had reflux into 60 single-system ureters and 12 duplex systems. Fifty-five single-system ureters have ceased refluxing and 4 of the remaining 5 have improved, whereas 7 of the 12 kidneys with reflux into one or both segments of a duplex system no longer reflux. Thirty-one patients had only single-system disease, and 26 (84%) are totally corrected. Of the 10 patients with 12 duplex systems that refluxed, 5 were completely corrected. Overall, 31 (76%) of the patients are free of reflux.

Endoscopic Treatment of Vesicoureteric Reflux in Transplanted Kidneys

Twenty-one patients underwent endoscopic subureteric injection of Polytef paste for the correction of secondary vesicoureteric reflux (VUR) in transplanted kidneys. Ureteroneocystotomy was performed in renal transplants using an extravesical technique in 19 patients and the Leadbetter-Politano technique in 2 cases. Success was achieved in only 6 patients, including the 2 ureters reimplanted according to the Leadbetter-Politano technique. No significant complication relating to the technique was observed. Despite the low success rate (30%), endoscopic treatment of VUR in transplanted kidneys is justified as a first attempt in view of the morbidity of VUR and the difficulties of repeated surgical reimplantation in this population.

The Irish paediatrics association and section of paediatrics, royal academy of medicine in Ireland

Since the initial experimental studies in pigs, treatment of vesicoureteral reflux (VUR)inehildrenby endoscopic subureteral injection of polytetrafluoroethylene paste has been used by several investigators with encouraging results. Thirty-seven children (32 girls, 5 boys) with VUR in duplex systems were treated endnscopieally by the senior author (PP) using subureteric Polytef O~ injection and followed up for 1 to 7 years. Thirty-one patients had unilateral refluxing duplex systems and six had bilateraIrefluxing duplex systems. Twenty-sevenrefluxing units had complete ureteral duplication and 16 had incomplete uretesal duplication. All refluxing units had higher grade VUR at least into one of the moieties of the duplex system; 74% of the refluxing duplex ureters having grade 1II VUR and 26% either grade 1V or grade V reflux. Reflux was corrected in 14 (87%) of the 16 ureters with incomplete ureteral duplication after a single injection of Polytet ~ paste and two ureters required two injections to correct VUR. Of the 27 refluxing units with complete ureteral duplication, reflux was corrected in 16 (59%) units after a single injection of Polytef~ paste. 3 (11%) duplex systems showed improvement to grade ] or II reflux after one injection and no further treatment was given. Eight (30%) units with complete ureteral duplication required two to four subureteric injections for the correction of VUR. 93% of refluxing units where reflux was corrected with one subureteric injection of PolytolX~t paste required less than 0.3ml of paste per unit to stop reflux. Thirty-six o f the 37 patients were discharged from the hospital on the day of the procedure. At follow-up micturating cystography 93% of duplex systems continue to show absence of reflux 1 to 7 years after endoscopic correction. There was no evidence of delayed appearance of vesicoureteral obstruction on sonography. No significant complications have been observed in our patients with the use of Teflon to correct reflux. This endoscopic day care procedure offers a simple ahemative in the treatment of refluxing duplex systems.

Efficacy and Causes of Failure of Endoscopic Subureteric Injection of Teflon in the Treatment of Primary Vesicoureteric Reflux

A total of 135 consecutive patients with primary vesicoureteric reflux (VUR) were treated as day cases using submucosal Teflon injection (STING) between 1984 and 1988. Up to 3 repeat procedures were performed in the event of failure; 89% of patients and 92% of ureters were cured. None was obstructed and 2 recurred. Eight patients continue to have asymptomatic reflux Grade 2 or less, while 7 have had open surgery to correct the reflux. Most of the failures had a satisfactory appearance at STING but this deteriorated with time and appears to have been caused by leakage of Teflon from the injection site post-operatively. There were no signs or symptoms of embolisation or migration of the implant material.

Treatment of Primary Vesicoureteric Reflux by Polytetrafluoroethylene Injection: A Middle-Term Follow-Up Study

We have selected 38 patients (55 ureters) with primary vesicoureteric reflux successfully treated by endoscopic subureteric injection of Teflon. The success rate after 1 injection was 83.6%. Nine ureters required a 2nd or even a 3rd injection of Teflon to achieve success. The follow-up time for these successfully treated patients was 2-5 years, and results remained stable in 94.5% of cases. Endoscopic injection of Teflon seems to be a reliable alternative to open surgery in the treatment of primary vesicoureteric reflux.

Endoscopic treatment of vesicoureteral reflux prior to renal transplantation.

Endoscopic subureteral injection of Teflon was done in 34 potential renal transplant recipients to correct vesicoureteral reflux. Follow-up ranged from 6 to 24 months. After one injection reflux was corrected in 53.7% of the patients; this increased to 64.8% after a second injection. The procedure is simple, effective, without major morbidity, and avoids the risk of nephroureterectomy. However, efforts must be made to find an ideal substance with a higher biocompatibility and without risk of migration.

Subureteral Collagen Injection for the Endoscopic Treatment of Vesicoureteral Reflux in Children. Followup Study of 97 Treated Ureters and Histological Analysis of Collagen Implants

Endoscopic subureteral injection has become an established alternative means for treating vesicoureteral reflux in select children. However, which injection material to use remains a controversy. Polytetrafluoroethylene (Teflon) has been injected in more than a thousand patients with few complications, although experimental and clinical studies have demonstrated migration of the injected particles into distant organs, such as the lungs and the brain, as well as local and metastatic granuloma formation.Therefore, we introduced, following experimental studies in the mini-pig model, glutaraldehyde cross-linked, highly purified bovine collagen† for injection. Between June 1988 and October 1991, 97 refluxing ureters in 66 children were treated by endoscopic subureteral collagen injection. In 58.8% of the ureters reflux was cured after 1 and in 77.3% after 2 injections. Considering improvement to grades I and II reflux without further treatment as success, the success rate increased to 68.0% after 1 and to 89.7% after 2 injections. Mean followup was 18.5 months (range 3 to 39 months). After 2 failed injections the patients either returned to antibiotic long-term prophylaxis or the reflux was operatively corrected. The operative procedure was never compromised by the preceding injection. A direct correlation between deficient length of the submucosal tunnel of the intravesical ureter and the iatrogenic malposition of the collagen deposits, and the failures could be demonstrated. Granuloma formation at the site of injection was not found. The results of the histological Investigation of the collagen deposits removed at open ureteral reimplantation for failures are reported. It could be demonstrated that endogenous fibroblasts invade the bovine collagen implant and that these cells show active production of new human collagen, types I and III, replacing the implant.

Endoscopic treatment of vesicoureteral reflux prior to renal transplantation

Abstract. Endoscopic subureteral injection of Teflon was done in 34 potential renal transplant recipients to correct vesicoureteral reflux. Follow-up ranged from 6 to 24 months. After one injection reflux was corrected in 53.7 % of the patients; this increased to 64.8 % after a second injection. The procedure is simple, effective, without major morbidity, and avoids the risk of nephroureterectomy. However, efforts must be made to find an ideal substance with a higher biocompatibility and without risk of migration.

Endoscopic correction of vesicoureteral reflux in the adult by Teflon injection

Appropriate therapy of vesicoureteral reflux is a controversial topic. Many studies have been performed to compare medical versus surgical treatment and various operations have been described to correct vesicoureteral reflux. In recent years, endoscopic subureteral Teflon Injection has been used successfully, mostly in children. We report our positive experience in 31 adults. The procedure proved to be simple and reliable. No complications have occurred.

CT and MR appearance of subureteric Teflon and periureteral teflon migration: A case report

We present the computed tomography (CT) and magnetic resonance (MR) findings of a case in which an adult patient underwent subureteric injection of polytetrafluoroethylene (PTFE; Teflon ™) (STING) to correct vesicoureteral reflux. We report the appearance of periureteral PTFE migration mimicking cystic pathology.

Endoscopic correction of primary vesicoureteric reflux by subureteric Teflon injection (STING): follow-up study in 123 patients

During a 4-year period 123 children (191 ureters) with primary vesicoureteric reflux (VUR) were treated endoscopically by subureteric Teflon injection (STING). They have now been followed up for periods ranging from 2 to 6 years. Sixty per cent of the ureters had grade III VUR and 36% had either grade IV or grade V. Reflux was corrected in 149 (78%) ureters after a single injection of polytef paste; 11 (6%) ureters showed improvement to grade I or II reflux after one injection and no further treatment was given; 24 (12%) ureters required two injections and 7 (4%) needed three to four subureteric injections for the correction of VUR. Of the 123 patients, 116 were discharged from the hospital on the day of the procedure. Of the 149 ureters corrected with one subureteric injection, 83% required less than 0.3 ml paste per ureter to stop reflux. At follow-up micturating cystography 91% of the ureters continue to show absence of reflux 2 to 6 years after endoscopic correction; 9% had recurrence of reflux, but more than one-half of the recurrences were only of grade I or grade II severity and required no further treatment. Seven ureters had recurrent grade III or IV reflux and were reinjected without any difficulty. There was no evidence of delayed appearance of vesicoureteric obstruction. Treatment of primary VUR by endoscopic subureteric injection of polytef paste was found simple, safe, and effective in correcting all grades of VUR.

Long-term histological results following glutaraldehyde cross-linked collagen injection into the suburothelial space of the mini-pig bladder

Endoscopic correction of vesicoureteric reflux by subureteric injection has become an accepted method of treatment in selected cases. Its efficacy has been demonstrated in the treatment of well over 1,000 ureters. However, there are doubts as to the long-term safety of the commonly injected substance Teflon. Glutaraldehyde cross-linked bovine collagen, a biodegradable substance, was suggested as an alternative material for injection. The aim of this study was to evaluate the histological long-term behavior of glutaraldehyde cross-linked bovine collagen injected into the mini-pig bladder. One hundred and eight deposits of cross-linked collagen, each containing 0.2 ml (n = 36) or 0.6 ml (n = 72) collagen paste, were injected into the suburothelial space of the bladders of 24 mini-pigs. The histological behavior of the implants was studied at monthly intervals over a period of 12 months. After only 2 months a marked invasion of host fibroblasts and formation of endogenous type I and III collagen could be observed. Over 12 months the invasion of fibroblasts and the formation of new collagen increased dramatically. No migration of collagen particles into the local lymphatic system could be observed. A new staining technique (solophenyl red 3BL) was introduced to selectively demonstrate type I and III collagen fibres. In addition, the efficacy of the subureteric collagen injections could be demonstrated by successfully treating reflux that was iatrogenically induced in the mini-pig bladders.

Endoscopic subureteric collagen injection (SCIN): a new alternative treatment of vesicoureteric reflux in children

Endoscopic subureteric injection has become an accepted form of treatment for vesicoureteric reflux in children in selected cases. However, the commonly injected substance Teflon has raised doubts as to its long-term safety. Glutaraldehyde cross-linked bovine collagen, which is not associated with the feared side effects of Teflon (granuloma formation, particle migration), seems to be an adequate replacement. At the Departement of Paediatric Surgery of the Basel University Children's Hospital 54 patients with a total of 82 refluxing units were treated with the subureteric collagen injection (SCIN) in the period between June 88 and August 90; 45 patients were female and 9 were male. The average age at treatment was 4.9 years (2 months– 15.2 years). Micturating cystourethrograms performed 3 months after injection showed disapperance of reflux in 61.3% (49 ureters).If improvement to grade I and II reflux was included, the success rate increased to 77.5%. After two SCIN procedures 77.6% of the ureters became free of reflux. Including improvement to grade I and II reflux, the success rate increased to 83.8%. The mean follow-up time was 11.5 months (2–27 months). Injection-related complications were not observed. Although the overall results were not as good as those after surgical correction of reflux and the long-term effects of the collagen implants are not yet known, SCIN seems to be a simple alternative treatment for vesicoureteric reflux in children.

Ureteral obstruction caused by subureteral Teflon injection

From January 1989 to July 1990 we performed the “sting” procedure on 253 ureters. The most significant complications were complete obstruction of the ureter in 2 patients with 3rd- and 4th-degree reflux following injection of 1.5 and 2 ml Teflon. Percutaneous nephrostomy was used as the initial treatment and ureterocystoneostomy as the subsequent surgery. Temporary post-Sting problems of urinary stasis were found in 16 of 167 children studied within the first 3 weeks by sonography or excretory urography.

Results of endoscopic subureteral collagen injection for reflux correction in pigs and dogs

The efficacy of endoscopic correction of reflux with the use of Teflon has been proven, but there are safety concerns because of granuloma formation and particle migration. Using glutaraldehyde cross-linked (GAX-) bovine collagen as an alternate biomaterial, animal experiments were performed with 6 female pigs and 20 beagle dogs. Primary and experimentally-induced vesicoureteral reflux was treated by endoscopic injection of bovine GAX-collagen (Zyplast) submucosally at the ureteric orifice. Radiographic controls after 6, 8, or 12 months revealed successful reflux correction in 14 of 19 treated ureters of dogs. After the animals were killed, pathohistological evaluation demonstrated persistence of the collagen depot at the site of injection even after 12 months, although not in all cases, without inflammatory or foreign-body tissue reaction. No evidence of particle migration was found. Invasion of fibroblasts and fibrocytes into the collagen depot and capillary vessel formation appeared the same after the different time intervals, and there was no difference between the two animal species. The biocompatibility of purified bovine GAX-collagen makes it an alternative to Teflon for reflux correction.

Endoscopic treatment of vesicoureteral reflux in children with neuropathic bladder

The authors report on the management of 15 patients with vesicoureteral reflux secondary to neuropathic bladder treated by endoscopic subureteral injection of polytef paste (Teflon) in the first 9 cases and collagen (Zyplast) in the last 6 cases. Their ages ranged from 18 months to 12 years. The degree of reflux ranged from grade II to grade V. The amount of paste injected varied from 0.2 to 1 ml Teflon and from 0.75 to 1.5 ml Zyplast. The endoscopic treatment was completely successful in 12 cases. The risks and benefits of endoscopic treatment versus medical and traditional surgical management are discussed. The endoscopic approach could be a valuable alternative to open surgical repair in vesicoureteral reflux secondary to neuropathic bladder.

Primary Vesicoureteric Reflux: Treatment with Subureteric Injection of Polytef Paste

A series of 34 children with 40 primary refluxing ureters were treated endoscopically with a subureteric injection of polytetrafluoroethylene paste (Polytef). The amount injected ranged between 0.1 and 0.8 ml (mean 0.3). A single injection cured the reflux in 26 ureters (65%) and the grade of reflux improved in a further 9 ureters. Seven ureters required a second injection and reflux was cured in 6 of these. The overall cure rate was therefore 80% after the second injection. There was one complication due to self-limiting ureteric obstruction following injection. The procedure is quick, easy to perform and effective. We have some reservations about the long-term efficiency and safety of subureteric Polytef injection in children.

Histological changes following submucosal teflon injection in the bladder

Histological examination following subureteric Teflon injection was carried out on 32 ureters and four granulomatous polyps. When the Teflon was correctly placed in the submucosa it remained circumscribed and reflux was more likely to be corrected. If the Teflon was placed more deeply it became diffuse, caused a giant cell reaction, and was less likely to correct the reflux. The granulomatous polyps may represent a reaction to leakage of Teflon from the injection site.

Endoscopic treatment of vesicoureteral refluxin children with neurogenic bladders

Endoscopic subureteral injection of Teflon was performed in 12 children (20 ureters) with neurogenic bladders and vesicoureteral reflux (grades III-IV). Follow-up evaluation by ultrasonography and voiding cystourethrogram at three-month intervals up to two years revealed successful correction of the reflux in 70 percent of the ureters.

Local tissue reaction to the subureteral injection of glutaraldehyde cross-linked bovine collagen in humans : M.P. Leonard, D.A. Canning, J.I. Epstein, et al. J Urol 143:1209–1212, (June), 1990

Local tissue reaction to the subureteral injection of glutaraldehyde cross-linked bovine collagen in humans : M.P. Leonard, D.A. Canning, J.I. Epstein, et al. J Urol 143:1209–1212, (June), 1990