Subureteral Injection Research Articles

Technical Considerations of Endoscopic Subureteral Injection for the Treatment of Vesicoureteral Reflux

The purpose of this study was to assess the long-term efficacy and the cause of failure in endoscopic subureteral injection for vesicoureteral reflux. For 5 years, a total of 73 patients (96 ureters) with primary grades I to V VUR were treated by one operator using subureteral injection of polydimethylsiloxane (PDS) and followed-up for more than 1 year. Cure was defined as an absence of VUR on voiding cystourethrography at 3 months after injection. Second and third injection was done for the failed cases. Statistical analyses were performed using the chi-square test. Endoscopic subureteral injection of PDS showed high success rate (82.3%) after single injection, 98% after second injection for the failed cases. Correction by grade was 75%, 83%, 89%, 83%, and 77% for grade I to V, respectively. In 17 units of second injection, cystoscopy showed mound displacement in 9 units, no volcano appearance but rather a broad elevation in 5 units, mound extrusion in 2 units, and distal ureteral fistula in 1 unit. Among 17 failed units, 58.8% (10/17) occurred in the first 18 months, meanwhile, failure rate decreased to 9.5% (7/74) in later 42 months during the 5 years' practice in our institute. In contrast to the generally accepted concept, the primary grade was not the main cause of success. Besides the primary reflux grade, available position according to the characteristics of the patients, injection method, the operator's skill and experience greatly affect the success rate.

Efficacy of the Modified STING Procedure for the Treatment of High Grade Vesicoureteral Reflux

Purpose: The modified subureteral transurethral injection (STING) has been reported to increase the success of endoscopic treatment of high grade vesicoureteral reflux (VUR). This study was performed to assess the efficacy of the modified STING procedure compared to conventional STING in the setting of high grade VUR. Materials and Methods: We retrospectively reviewed the medical records of 40 consecutive children (46 ureters) with a median age of 5.32 years (range 1 to 10 years) who underwent endoscopic treatment of grade IV to grade V VUR between February 2004 and December 2006. The modified STING was performed by applying a direct pressure stream of irrigation fluid into the ureter in order to define the injection site within the ureteral submucosa. The needle was then placed in the ureteral tunnel, and a dextranomer/hyaluronic acid copolymer (Dx/HA) was injected into the submucosal intraureteral space, tracking along the entire length of the detrusor tunnel. Modified STING was performed in 27 ureters (grade IV: 13, grade V: 14), and conventional STING was performed in 19 ureters (grade IV: 12, grade V: 7). Follow-up voiding cystourethrography (VCUG) was performed 3 months later. Results: Complete resolution occurred in 82% (22/27 ureters) of the patients undergoing modified STING, including 92% (12/13) of grade IV patients and 71% (10/14) of grade V patients. Three ureters required a second injection to correct VUR. Conventional STING had a success rate of 63% (12/19), [75% (9/12) in grade IV and 43% (3/7) in grade V]. The mean injected volume for the modified STING was 1.23±0.3ml, while that for the conventional STING was 0.95±0.2ml (p=0.03). Conclusions: The modified STING was markedly more successful in the treatment of high grade VUR and carried no significant adverse effects.

Endoscopic management is the preferred "treatment" modality for grade III vesicoureteric reflux with breakthrough infections in a young girl

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 vesicoureteric reflux (VUR). Successful elimination of reflux in about 80% of patients after a single injection (and in 90% after a repeat) has been achieved using non-degradable substances. young girl with grade III VUR and breakthrough infections would definitely need to undergo antireflux procedure. Endoscopic treatment would be an ideal procedure as it is a one-day surgery, with over 80% success rate, low morbidity and no long-term complications. Moreover, this form of surgery is appealing to, as well as the choice of the majority of parents.

Effect of Subureteral Injection of Polydimethylsiloxane (PDS) in Children with Vesicoureteral Reflux

Subureteral injection of bulking agents is an accepted, less invasive, treatment of vesicoureteral reflux (VUR) in children. We evaluated the efficacy of an endoscopic subureteral polydimethylsiloxane (MacroplastiqueR) injection with primary VUR in children. A total of 21patients (31 renal units), aged between 2 and 15 years were included in this study. The vesicoureteral reflux was grade I in 5, grade II in 7, grade III in 9, grade IV in 7 and grade V in 3 renal units. PDS was injected submucosally under the ureteric orifice, converting the opening to allow the elevation of the mucosa, so that the orifices lay on the summit of a small mound, which assumed an elevated crescent appearance by the end of the procedure. The patients were followed up from 6 to 24 months (mean 18.5 months) with voiding cystourethrography. Overall, the reflux was corrected in 26 of the renal units (83.8%) in one injection. The correction rates, according to the reflux grade, were 100, 100, 88.8, 71.4, 66.7% for grades I to V, respectively. There were no associated postoperative complications. The mean hospital stay and operation time were 2.7 days (2∼4 days) and 17.5 minutes (12∼25 minutes), respectively. In conclusion, for low grade reflux, subureteral PDS injection therapy could be a primary treatment for VUR in children because it is simple, less invasive, decreased hospital stay and showes a high success rate.

Tissue formation following implantation of cultured elastic chondrocytes for treatment of vesicoureteral reflux

Vesicoureteral reflux (VUR) is the retrograde passage of urine from the bladder into the ureter and kidneys during voiding. Its pathophysiology appears to be related to the valve mechanism of the ureterovesical junction, high intravesical pressure, bladder neurogenic disorder or immature bladder. Abnormal location of the ureteral orifice is implicated in the short ureteral tunnel, which in turn compromises the flap-valve mechanism. Endoscopic subureteric injection of various materials has become a universally accepted mode of treatment for VUR in recent years. Different kinds of injection materials have been used for injection with various success rates [1–3]. Tissue engineering is an interdisciplinary field that applies the principles of engineering and life sciences to the development of biological substitutes that restore, maintain or improve the function of tissue or of a whole organ [4]. Treatment of VUR by endoscopic implantation of cultured autologous elastic chondrocytes (ACI—autologous chondrocyte implantation) under the ureteral orifice—a method based on tissue engineering technologies—has proved to be successful in eliminating or downgrading high-grade VUR and has enabled surgical treatment to be abandoned in paediatric patients [5]. We have developed a method for implantation of cultured elastic chondrocytes, together with the patient’s autologous plasma, for treating VUR in patients with chronic renal failure who are candidates for renal transplantation [6]. The effectiveness of cell implantation for VUR treatment is usually evaluated by X-ray contrast cystography, but it is normally not possible to investigate the quality of regenerated tissue. In the present case we were able to in-

Late Onset Ureteric Obstruction After Endoscopic Subureteric Injection of Calcium Hydroxyapatite for Primary Vesicoureteric Reflux

Ureteric obstruction occurs in about 1% of cases undergoing endoscopic treatment of vesicoureteric reflux (VUR). It usually develops shortly after treatment. We report on a case of obstruction occurring 1 year after subureteric injection of calcium hydroxyapatite. Obstruction was progressive and eventually required open ureteric reimplantation. Ureteric obstruction can occur also in the long-term after endoscopic treatment of VUR and even in the absence of symptoms. Although it is so rare as to make long-term follow-up of all treated cases cost ineffective, physicians should be aware of such complications, especially while testing new bulking agents.

Ipsilateral Ureteroureterostomy in the Surgical Management of the Severely Dilated Ureter in Ureteral Duplication

Ipsilateral ureteroureterostomy for the surgical management of severely dilated ureter in ureteral duplication is well supported in the surgical literature but often not done. We evaluated our institutional experience with ureteroureterostomy in duplication anomalies to assess the feasibility and success of this procedure. An 8-year retrospective review of the records of all patients with complete renal duplex anomalies was evaluated. Anatomical presentations, and operative and nonoperative treatment of these patients were evaluated. A total of 193 patients were identified with complete renal duplication. Associated anomalies included ureterocele in 24 patients, ectopic ureter in 38 and vesicoureteral reflux in 57. Of 193 patients 160 (83%) with duplex anomalies underwent surgical intervention with a total of 41 ureteroureterostomies performed in 39 patients with dilated donor ureters. A total of 11 ureteroureterostomies were performed primarily and 30 were performed in conjunction with ipsilateral ureteral reimplantation of the distal common segment below the ureteroureterostomy. Ten of the 39 patients had the contralateral side reimplanted for vesicoureteral reflux. In all children with ureteroureterostomy the anastomosis between the 2 ureters remained patent. Two of the 11 children who underwent ureteroureterostomy alone had de novo ipsilateral vesicoureteral reflux (1), which was treated with ureteral reimplantation, and subureteral injection (1). Two children who underwent concomitant ureteroureterostomy and reimplantation without indwelling stents had transient postoperative urinomas that required subsequent drainage. Additionally, 3 patients had persistent ipsilateral vesicoureteral reflux, which was treated with subureteral injection in 1 and observation in 2. One patient presented with transient ipsilateral urinary obstruction, which required percutaneous drainage and resolved spontaneously. In cases of ureteral duplication with a severely dilated ureter requiring surgical intervention ipsilateral ureteroureterostomy is a viable option for reflux and/or obstruction. The procedure is rapid and technically feasible, and it offers excellent cosmesis. In addition, ureteroureterostomy has minimal morbidity and it facilitates early hospital discharge.

Multivariate Comparison of the Efficacy of Intraureteral Versus Subtrigonal Techniques of Dextranomer/Hyaluronic Acid Injection

Numerous factors have been postulated to increase success rates for dextranomer/hyaluronic acid injection for vesicoureteral reflux. Ureteral hydrodistention combined with intraureteral injection reportedly improves injection success rates. We combined the results of 5 pediatric urologists to evaluate the efficacy of this technique compared to that of subtrigonal-only injection in relation to other factors. Patients with primary vesicoureteral reflux undergoing dextranomer/hyaluronic acid injection from April 2002 to December 2005 at 2 institutions were eligible. Only patients with primary vesicoureteral reflux were included in the study. Injection success was defined as the complete absence of reflux on followup voiding cystourethrogram or radionuclide cystogram. Predictors of a successful outcome were analyzed statistically with logistic regression. Factors included in our analysis were gender, age, vesicoureteral reflux grade, dysfunctional voiding, amount of injected dextranomer/hyaluronic acid, injection technique (intraureteral vs subureteral) and surgeon. A total of 301 patients (453 ureters) with a median age of 5.5 years met inclusion criteria, of whom 199 (66%) were cured at 3 months of followup. Of the patients 145 (48%) underwent subureteral injection and 156 (52%) underwent ureteral hydrodistention combined with intraureteral injection. On multivariate analysis only vesicoureteral reflux grade (p <0.001) and surgeon (p = 0.01) were significantly predictive of injection success. There was a trend toward significance with ureteral hydrodistention combined with intraureteral injection (p = 0.056). In our multivariate model only vesicoureteral reflux grade and surgeon were independently predictive of injection success in patients with primary, uncomplicated vesicoureteral reflux. There was a trend toward improved results with ureteral hydrodistention combined with intraureteral injection, although this did not achieve statistical significance.

Histopathological Changes Associated With Dextranomer/Hyaluronic Acid Injection for Pediatric Vesicoureteral Reflux

Few studies have examined the medium and long-term histological changes associated with periureteral injection of dextranomer/hyaluronic acid copolymer (Deflux(R)). We present the results of a histological review of a series of distal ureteral excisions in patients undergoing ureteroneocystostomy after failed dextranomer/hyaluronic acid injection. All patients undergoing ureteroneocystostomy after failed dextranomer/hyaluronic acid injection(s) at 1 institution were eligible for this study. Excised ureteral segments were histologically examined by a single urological pathologist. An immunohistochemical battery was used for each specimen, including hematoxylin and eosin, CD3, CD20, MIB-1 and trichrome stains. Pathological criteria included the presence, location and intensity of fibrosis, giant cell reaction, chronic inflammation, free dextranomer/hyaluronic acid, and CD3, CD20 and MIB-1 staining. Pathological features were correlated with the time from injection to surgical excision. The ureters of 16 children with a mean age of 4.5 years were examined. Median time from injection to implant excision was 8 months. Giant cell reaction was present in 94% of patients and it was typically located in the serosa. No histological or immunophenotypical feature correlated with the duration of implantation except CD3+ and CD20+ lymphocyte counts, which increased with time from injection (p = 0.06 and 0.02, respectively). Dextranomer/hyaluronic acid appears to be stable and safe for use after 3 to 22 months of followup of subureteral injection. The periureteral inflammatory reaction increases with time, although no increases in nuclear turnover or fibrosis were detected.

Endoscopic Treatment of Vesicoureteral Reflux Associated With Ureterocele

We determined the value of endoscopic treatment for vesicoureteral reflux associated with ureterocele. From 1984 to 2005, 109 children with a median age of 6 months underwent endoscopic ureterocele puncture. Ureterocele presented as a part of a duplex system in 97 of patients (89%) and as part of a single system in 12 (11%). Vesicoureteral reflux was seen to the lower ipsilateral moiety in 53 patients and in 32 contralateral kidneys (85 refluxing renal units). Puncture was performed with a 3Fr Bugbee electrode. High grade vesicoureteral reflux or breakthrough infection while on antibiotic prophylaxis served as the indication for the surgical correction of vesicoureteral reflux. Median followup after endoscopic correction was 10 years (range 1 to 21). Spontaneous vesicoureteral reflux resolution following successful ureterocele puncture was seen in 36 of the 85 refluxing renal units (42%) and in 5 (6%) reflux was downgraded. The latter patients were withdrawn from antibiotic prophylaxis and they did well. A total of 33 refluxing renal units with vesicoureteral reflux into the lower moiety of the ureterocele kidney and 11 contralateral refluxing renal units underwent endoscopic correction. Reflux was corrected in 31 of the 44 refluxing renal units (70%) after a single injection and it resolved after a second injection in another 9 (21%). In 4 refluxing renal units (9%) endoscopic correction failed and open reimplantation was done. Of the 109 patients (13%) 14 had vesicoureteral reflux to the ureterocele moiety following endoscopic puncture. Of those patients endoscopic correction resolved reflux in 3, reflux resolved spontaneously in 5 and upper pole partial nephrectomy was performed in 4 due to a nonfunctioning moiety. The remaining 2 patients did well without antibiotic prophylaxis. Our data show that endoscopic treatment of vesicoureteral reflux associated with ureterocele is a simple, long-term effective and safe procedure, avoiding the need for open surgery in the majority of patients following endoscopic puncture of ureterocele.

Role of prophylaxis in vesicoureteral reflux

Traditional management of vesicoureteral reflux focuses on preventing renal complications associated with ascending urinary tract infection by either providing continuous antibiotic prophylaxis to sterilize the urine and thus prevent recurrent infection, or abolishing reflux via surgical intervention. This review will consider the rationale for antibiotic prophylaxis in light of contemporary data regarding the natural history of vesicoureteral reflux, urinary tract infection and renal scarring, as well as the efficacy of various treatment strategies. Recent studies have shown that in grades I-IV vesicoureteral reflux, open surgical intervention compared with antibiotic prophylaxis is no better at preventing renal complications. Endoscopic subureteral injection of biomaterials has been proposed as a cost-effective, minimally invasive alternative to surgical or medical intervention; however, given the variety of materials and techniques, the literature has yet to achieve consensus on its efficacy. The first study to compare antibiotic prophylaxis with increased surveillance and prompt treatment of urinary tract infection shows no difference between the two approaches in low-grade (grades I-II) vesicoureteral reflux. Recent studies have challenged the traditional paradigm of aggressive vesicoureteral reflux management with surgery or antibiotic prophylaxis. In light of these findings, pediatric urologists will need to reexamine treatment modalities for vesicoureteral reflux.

Long-term results of endoscopic treatment of vesicoureteral reflux with the sub-ureteric injection of calcium hydroxyapatite

To review our long-term results of the sub-ureteric injection of calcium hydroxyapatite in the endoscopic management of vesicoureteral reflux (VUR) in children. A sub-ureteric injection of calcium hydroxyapatite was given to 14 children (23 ureteral units) affected by VUR grades I-V. All children were followed-up with monthly urine cultures, and a renal ultrasound was done on the postoperative 4th week, while the first voiding cysto-urethrogram (VCUG) control was performed on postoperative week 12. The children were followed-up with yearly renal ultrasound and monthly urine cultures, thereafter. Data from the patients' charts were retrospectively analyzed regarding the outcome of the procedures. Mean follow-up time was 52 months (47-60 months). VUR was cured in 47.4% of cases after a single injection. After the second injection the global success rate was 52.1%. Ureteroneocystostomy was performed on seven refluxing ureters of five children unresponsive to sub-ureteric injection therapy. One patient underwent nephroureterectomy because of a non-functioning kidney secondary to ureteral obstruction due to migration of material at the 23rd month postoperatively. Although favorable short-term success rates have been reported with the sub-ureteric injection of calcium hydroxyapatite without any side effects, our long-term results showed a low success rate, with the only reported serious morbidity.

Symptomatic Calcification of Subureteral Collagen Ten Years After Injection

Bovine glutaraldehyde cross-linked collagen is an injectable bulking agent used to treat urinary incontinence and vesicoureteral reflux. A 16-year-old girl had previously undergone left subureteral injection of collagen at the age of 6 years. She presented to our clinic after passing a 7-mm calcification with a history of hematuria and intermittent back pain. Computed tomography showed two hyperdense foci measuring 2 mm each in the region of the left ureterovesical junction that did not change on follow-up imaging. On cystoscopy, two submucosal calcifications were located medially and inferiorly to the left ureteral orifice and were removed endoscopically.

Minimally invasive treatment for vesicoureteral reflux in children: a selective approach with effective cure for all

Purpose We report a minimally invasive treatment protocol for vesicoureteral reflux (VUR) in infants and children with a selective use of dextranomer/hyaluronic acid copolymer (Deflux) injection for mild grades or uncomplicated VUR and pneumovesicoscopic ureteric reimplantation for severe grades or complicated VUR. Material and methods Children presenting with persistent primary VUR (Grade II - V) refusing antireflux surgery were recruited. At entry, each patient had a voiding cystourethrogram (VCUG), renal ultrasonogram (US), isotopic renogram (DMSA).The minimally invasive management protocol included 1) endoscopic sub-ureteric injection for milder grades (Grade II -III, Grade IV unilateral) and 2) endoscopic Cohen's cross-trigonal ureteral reimplantation with CO2 pneumovesicum for dilating (Grade IV Bilateral to Grade V) VUR, associated with UTI and multiple pyelonephritic renal scarring. Resolution of VUR was confirmed by VCUG at a minimum follow up period of 6 months after the procedure. Results One hundred and seventeen patients (45 bilateral) were treated. Endoscopic sub-ureteric injection was given to 24 children (M/F: 8/16, Mean age: 5.75 ± 3.61yrs,72 refluxing ureters) and Endoscopic cross-trigonal ureteric reimplantation was successfully performed in 93 children (M/F: 72/21, Mean age: 5.1 ± 5.61, 90 refluxing ureters). Follow-up cystogram showed complete resolution of VUR in 69 ureters (96%), and in 89 ureters (99%), in those who underwent subureteric injection and ureteric reimplantion respectively. VUR downgraded in 1 (underwent surgical intervention) and persisted in 3 ureters treated with subureteric injection and were treated successfully by repeat injection. Conclusions This new minimally invasive treatment algorithm with a combined and selective use of Deflux injection for mild grades of VUR and endoscopic pneumovesical ureteral reimplant for severe VUR offers a very effective cure for all grades of VUR. The very high cure rate alleviates the need for follow-up VCUG's and long term antibiotic treatment.

The durability of a single successful endoscopic polytetrafluoroethylene injection treatment: 14 year followup results

Purpose Long term durability of success after endoscopic correction with a single injection of bulking agents has not been addressed. It is not agreed on how and for how long we should follow up these cases. We reviewed our 14-year experience with successful single endoscopic subureteral poltetrafluoroethylene (PTFE) injection for the treatment of primary vesicoureteral reflux in children. Material and methods We retrospectively reviewed the charts of 42 patients with primary vesicoureteral reflux who were treated with a single successful subureteral PTFE injection from 1989 to 1993 and followed-up by routine 1, 3, and 10-year voiding cystourethrograms. Results The study included 30 girls and 12 boys between 2 years and 14 years old (median age 6 years). Four patients were lost to follow-up. Of the 38 patients 28 had unilateral and 10 had bilateral primary vesicoureteral reflux. Endoscopic treatment by subureteral PTFE injection was performed in 48 ureters. Patients were followed 10-14 years with a mean follow-up of 12.5±2.1. Voiding cystourethrography in 38 patients with 48 ureters revealed that 35 ureters (73%) remain free of reflux whereas reflux recurred in 13 (27%). Median recurrence time was 2 years. Of these 13 ureters, recurring reflux was grade I-II in 5 and grade III-V in 8. Reflux recurred in 11 of 24 ureters with grade IV-V reflux. 10 of 13 recurrences were detected by febrile urinary tract infections and only 3 Grade I recurrences were detected by voiding cystourethrography alone. No untoward effects were seen in any of these patients with injection of PTFE. Conclusions Following a single successful endoscopic injection for vesicoureteral reflux long-term follow-up may be warranted particularly in high-grade reflux. However, follow-up voiding cystourethrograms can be avoided except for cases with a febrile urinary tract infection.

Dysfunctional voiding and reflux – combined treatment with botulinum toxin A and dextranomer/hyaluronic acid

Background Dysfunctional voiding (DV) may exacerbate vesicoureteral reflux(VUR) or cause breakthrough UTI. DV has also been implicated as a risk factor for failure of Dextranomer/Hyaluronic acid (Deflux) injection. Endoscopic injection of botulinum toxin A (Botox) at the external sphincter has been used for DV, but simultaneous therapy for VUR with Deflux has not been reported. Methods Retrospective review of children undergoing endoscopic therapy with Botox or Deflux was performed over 2 years to identify children receiving simultaneous injections. Results Over a 2 year period, 31 children underwent subureteric injection of Deflux for VUR and 11 children underwent intrasphincteric injection of Botox for DV. Of these cases, 5 involved simultaneous therapy. These children ranging in age from 5–16 years, presented with incontinence, constipation, and/or prior pyelonephritis. In spite of biofeedback in 80%, symptoms persisted with urodynamic testing showing an interrupted uroflow pattern / increased EMG activity and postvoid residual. VUR ranged from grade 2-4, on the more severely affected side, with 50% showing reflux nephropathy. Botox injection of 100 units was transurethral in boys, and periurethral in girls with EMG guidance. All patients showed improvement in voiding parameters and symptoms. Deflux injections were successful in all cases of primary VUR. Conclusion VUR and DV often coexist. Combined therapy with Botox / Deflux allows both disorders to be treated simultaneously, with good outcomes.

Place of minimal access ureteral reimplantation in children

Purpose Transvesical ureteral reimplantation under pneumovesicoscopy is a new alternative to open surgery. Our goal is to confirm its efficacy, safety and to clarify its limits. Material and methods A total of 80 patients with a mean age of 50 months underwent laparoscopic transvesical reimplantation using three working ports (3 to 5mm) for ureterocele (3 cases), obstructive megaureter (7 cases) primary vesico ureteral reflux (70 cases). A total of 131 ureters were reimplanted. 8 patients were operated on after subureteric injection failure. Results After the first ten cases (learning curve) the conversion rate was 2/70 (3%). The mean operative time was 110 min for unilateral and 145 min for bilateral reimplantation. The mean hospital stay was 3,5 days. 3 cases were complicated by a postoperative urinary leak and 2 cases had transient upper urinary tract dilatation. The mean follow-up was 31 months. A follow-up cystogram was performed in 48 patients (75 ureters). Non symptomatic low grade reflux was present in 4 ureters in 4 patients: The success rate was 92% for patients and 95% for ureters. 3 cases presented with a recurrent urinary tract infection without reflux. No case needed to be reoperated upon. Conclusions After 5 years of practice, transvesical ureteral reimplantation under pneumovesicoscopy has now been perfected. Its results are similar to classical open surgery but the indications must be selected: children under one year and huge megaureters should be excluded; because of its cosmetic advantage this new technique could have its place in cases of primary VUR in girls, between sub mucosal injection and open surgery.

Subureteral copolymer injection is not cost-effective as initial therapy for VUR

Subureteral copolymer injection is not cost-effective as initial therapy for VUR

Experience of Subureteral Polydimethylsiloxane Injection Treatment in Children with Vesicoureteral Reflux

Purpose: Our data was retrospectively reviewed to assess the efficacy, safety and costs of endoscopic subureteral polydimethylsiloxane (PDS, Macroplastique) injection treatment for children with vesicoureteral reflux (VUR). Materials and Methods: Between December 1997 and May 2006, a total of 24 (29 renal units) VUR patients, whose parents showed reluctance toward open surgery, underwent subureteral PDS injection treatment. All of the patients were postoperatively assessed by voiding cystourethrography (VCUG) and ultrasound to evaluate any complications and reflux. The medical costs of the injection treatment were compared with those of open surgery for VUR over the same period. Results: The mean follow-up was 15 months (range 2-72). Of the 29 renal units treated, 24 (82.8%) were cured. Hydronephrosis, which postoperatively developed in three renal units, was spontaneously improved or resolved after minimal endourological procedures. Temporary gross hematuria and voiding difficulty occurred in one patient each, but were also improved. The total medical costs of the injection treatment were cheaper than those of open surgery (p<0.05). Conclusions: An endoscopic subureteral PDS injection is an effective and safe procedure; in addition, compared to open surgery, is an economic treatment for children with VUR. (Korean J Urol 2007;48:82-86) ꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏꠏ

Use of collagen for endoscopic correction in complicated vesicoureteral reflux

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. 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. 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. 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.