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Biomedical subjects

A Stenberg

Publications and source records attributed to A Stenberg.

At least 19 recordsLinked to original sources
PubMed2006

Distal shunt obstruction in children with myelomeningocele after bladder perforation.

PURPOSE: We studied short-term complications and particularly the signs of shunt dysfunction after augmented bladder perforation in patients with myelomeningocele and ventriculoperitoneal shunts. MATERIALS AND METHODS: In our series of bladder augmentations in 27 patients with myelomeningocele and a ventriculoperitoneal shunt in the last 10 years (1994 to 2004) we noted 4 who were 8 to 16 years old at our institute with bladder perforation 2 to 5 years after augmentation. Three patients received a colonic augmentation and 1 received an ileal augmentation. One patient underwent surgery for small bowel obstruction 2 years after the primary operation, when a hole in the augmented bladder was identified and oversewn. The other 3 bladder perforations occurred spontaneously or after failure to catheterize. An additional patient with spontaneous perforation underwent auto-augmentation elsewhere. RESULTS: After primary open abdominal surgery and enterocystoplasty there was no sign of shunt dysfunction in any patient. Bladder perforation and leakage of free urine into the abdominal cavity occurred in 4 of the 5 patients. In those patients severe symptoms of shunt dysfunction, including headache and high intracranial pressure, were noted 2 to 7 days after perforation. In patient 1 there was only urine leakage into a small cavity close to the bladder and no acute signs of post-perforation shunt dysfunction. In all cases the shunt was externalized for 1 to 6 weeks without further complications. CONCLUSIONS: In patients with myelodysplasia who have bladder perforation and free urine in the abdominal cavity the peritoneum is chemically inflamed by urine. Resorption of cerebral liquor may be disturbed, leading to shunt dysfunction and high intracranial pressure. Therefore, it is important for the urologist to recognize and evaluate postoperative signs and symptoms of increased intracerebral pressure in patients with bladder perforation. If found, early computerized tomography of the brain is recommended.

Adolescent↗
PubMed2003

Endoscopic treatment with dextranomer-hyaluronic acid for vesicoureteral reflux: histological findings.

PURPOSE: Dextranomer-hyaluronic acid co-polymer is the first endoscopic bulking agent approved for vesicoureteral reflux in the United States. We evaluated the histopathological changes associated with this treatment in children with vesicoureteral reflux. MATERIALS AND METHODS: Children 1 to 11 years old in whom treatment with dextranomer-hyaluronic acid co-polymer for grades III or greater vesicoureteral reflux had failed were eligible for the study. Failure was defined as persistent vesicoureteral reflux on voiding cystourethrography done approximately 3 months after implantation. At ureteral reimplantation the implant and surrounding ureteral tissue were resected and fixed for histopathological analysis. Tissue sections (4 to 5 microm.) were stained for routine histology and examined under a light microscope. Patients with a similar grade of vesicoureteral reflux who had not undergone endoscopic treatment served as the control group. RESULTS: The study population comprised 23 patients with vesicoureteral reflux, of whom 13 with a mean age of 2 years 8 months at diagnosis underwent 1 to 3 treatments with dextranomer-hyaluronic acid co-polymer. The remaining 10 patients with a mean age of 1 year 10 months at diagnosis did not receive the bulking agent before ureteral reimplantation. The implant remained in situ 13 to 39 months (mean 22). On ureteral reimplantation the implant was located at the site of injection in 12 of the 13 patients. Histologically a granulomatous inflammatory reaction indicated by giant cell infiltration was observed at the implantation site. At ureteral reimplantation 9 implants were pseudo-encapsulated. Calcification was present in 9 ureters, while the eosinophil count was greater than 5 cells per 0.125 mm2 in 7 ureters treated with dextranomer-hyaluronic acid co-polymer. Mast cell infiltration was similar in the treatment and control groups. CONCLUSIONS: Endoscopic treatment with dextranomer-hyaluronic acid co-polymer for vesicoureteral reflux is associated with a granulomatous reaction of the giant cell type, inflammatory cell infiltration and implant pseudo-encapsulation. They are typical histological findings associated with implantation of a foreign material. Dextranomer-hyaluronic acid co-polymer remains safe and effective for vesicoureteral reflux in children.

Adolescent↗
PubMed2002

Vasopressin and hypercalciuria in enuresis: a reappraisal.

OBJECTIVE: To test the hypotheses that vasopressin deficiency or hypercalciuria are important in polyuric and non-polyuric bedwetting, as nocturnal polyuria is a pathogenetic factor in enuresis responsive to antidiuretic therapy with desmopressin. SUBJECTS AND METHODS: Vasopressin deficiency has been implicated as a cause of nocturnal polyuria, but measurements of vasopressin in plasma have given contradictory results, because the hormone is released in pulses. Urinary levels reflect the secretion over longer periods. Hypercalciuria has also been proposed as a pathogenetic factor. Twenty-eight enuretic children who responded to desmopressin therapy with or without added anticholinergic agents (diuresis-dependent enuresis, DE), 15 children with therapy-resistant enuresis (not diuresis-dependent, NDE) and 51 continent controls were assessed. Urinary vasopressin, calcium and osmolality were measured in the morning after a 12-h thirst provocation. Urine production was recorded for 2 days. RESULTS: Because most data were not normally distributed, the values are expressed as the median (range). There were no differences in urine osmolality; i.e. con-trols 919 (636-1232), DE 849 (462-1149), NDE 968 (664-1191) mOsml/kg); vasopressin, controls 34 (8-983), DE 26 (9-295), NDE 50 (9-116) pmol/L; or calcium excretion (expressed as the calcium/creatinine ratio), controls 0.16 (0.01-0.71), DE 0.14 (0.04-0.67), and NDE 0.23 (0.03-0.69). The DE group produced more urine, at 18.4 (9.2-52.5) mL/kg/day, than the other groups, i.e. control 12.7 (8.3-42.8) and NDE 12.1 (6.3-36.8) mL/kg/day (P = 0.008). CONCLUSION: All enuretic children with nocturnal polyuria do not have vasopressin deficiency. The urinary calcium excretion does not differ between enuretic and dry children.

Adolescent↗
PubMed2002

The effect of endoscopic injections of dextranomer based implants on continence and bladder capacity: a prospective study of 31 patients.

PURPOSE: A prospective study was conducted to assess the efficacy of dextranomer based implants as a new bulking agent for endoscopic treatment of pediatric structural incontinence. MATERIALS AND METHODS: A total of 33 children and adolescents 5 to 18 years old with severe incontinence due to sphincteric incompetence (exstrophy-epispadias in 13, neuropathic bladder in 16, bilateral ectopic ureters in 4) were enrolled in the study. All but 1 patient wore diapers. Preoperative evaluation consisted of medical history, pad test, urine culture, urinary tract ultrasound and videourodynamics. This evaluation was repeated 6 months and 1 year after treatment and then on a yearly basis. Of the patients 14 had 2 and 1 had 3 treatment sessions to achieve a definitive result. At each evaluation the patient was considered cured-dryness interval of 4 hours confirmed by pad test, significantly improved-minimal incontinence requiring no more than 1 pad a day with less than 10 gm. leakage during pad test; and no further treatment required, and treatment failure-no significant improvement. Videourodynamics were mainly useful to study the evolution of the bladder capacity, activity and compliance. Followup after the last injection ranged from 6 to 36 months (mean 18). RESULTS: The mean injected volume was 3.9 ml. (range 1.6 to 12) and the procedure lasted a mean of 30 minutes (10 to 60). In the postoperative period 2 patients had temporary dysuria and 10 had a nonfebrile urinary tract infection. At 1 month 24 of the 33 patients (73%) were dry or improved. Two patients were subsequently excluded from study for noncompliance with followup. At 6 months 17 of 31 patients (55%), at 1 year 13 of 28 (46%), at 2 years 10 of 23 (43%) and at 3 years 10 of 20 (50%) were dry or improved. Similar success occurred in cases of neuropathic bladder (57%) and exstrophy-epispadias complex (46%). Success rate of re-treated patients was 35%. Of 13 patients with a normal initial bladder capacity 3 had a bladder decompensation requiring augmentation after 6 months. Also an increase of at least 50% in capacity was observed in 12 of 18 patients with an initial small bladder. No side effect related to the substance was observed. CONCLUSIONS: Endoscopic treatment of pediatric structural urinary incontinence with dextranomer implant, a nontoxic, nonimmunogenic, nonmigrant synthétic substance, was effective after 3 years in half of our patients. It may also be beneficial for patients with small bladder functional capacity. As the success rate decreased during the first year of followup, the result observed at 1 year seems to remain stable subsequently.

Adolescent↗
PubMed2002

Suicide mortality among electricians in the Swedish construction industry.

OBJECTIVES: To investigate the risk of suicide in Swedish electricians employed in the construction industry. A few studies have indicated an increased risk of suicide for electricians in the construction industry and electricians exposed to electromagnetic fields. METHODS: This is a cohort study. Electricians were identified through a computerised register of construction workers who had participated in health examinations in 1971-92. In this register, 33,719 male electricians were identified together with a reference group consisting of 72,653 male glass or woodworkers. Through a linkage with the Swedish Death Register, the cause of death was identified to the end of 1997. Mortality as a result of suicide was also compared with the general population with adjustments for sex, age, and period. RESULTS: The risk of mortality from suicide was decreased for electricians (standardised mortality ratio (SMR) 0.58, 95% confidence interval (95% CI) 0.47 to 0.71) and for the reference group of construction workers (SMR 0.81, 95% CI 0.72 to 0.91) compared with the general population. CONCLUSION: Contrary to some other studies, risk of suicide was not increased among electricians in the construction industry.

Adult↗
PubMed2001

Pressure flow measurement of hydronephrosis in children: a new approach to definition and quantification of obstruction.

PURPOSE: Hydronephrosis due to obstruction of the ureteropelvic junction is not uncommon in children. The critical level of outflow resistance characterizing obstruction remains to be established. It was previously found in our laboratory that the outflow resistance could be calculated in an animal model by servoregulating the infused flow to preset pressure levels. We determine whether this procedure is also feasible in patients with hydronephrosis. MATERIALS AND METHODS: A total of 46 patients with 48 hydronephrotic kidneys were examined. There were 32 boys and 14 girls with a diagnosis of hydronephrosis and suspected ureteropelvic junction obstruction who underwent a pressure flow study under general anesthesia for evaluation before possible surgery. The kidney was punctured percutaneously under ultrasonic guidance, and the study was performed under fluoroscopy. Flow levels were measured when steady state flow was achieved at pressures 5, 10, 15, 20, 25 and 30 mm. Hg greater than the intra-abdominal pressure. A conventional Whitaker test at an infusion rate of 10 ml. per minute was performed for comparison. The patient then underwent pyeloplasty if the kidney was considered obstructed. RESULTS: There were 2 patients excluded from evaluation because of significant leakage of contrast medium. Stable and repeatable recordings were obtained in all pressure flow studies but only in 7 of 46 Whitaker tests. A total of 41 kidneys were considered obstructed at pressure flow studies and operated on. The resistance was pressure dependent. Thus, mean resistance in the previous range 5 to 15 mm. Hg was considered a good overall measure of outflow resistance. Mean resistance less than 0.75 was normal and greater than 1.25 obstruction. There were 7 patients who had crossing vessels and a high mean resistance (3 or greater). CONCLUSIONS: The Whitaker test proved to be of no value for calculating the outflow resistance in ureteropelvic junction obstruction. The pressure flow study is superior to the Whitaker test for determining the outflow resistance and also allowing categorization of ureteropelvic junction obstruction.

Child↗
PubMed2001

Long-term followup of children treated with dextranomer/hyaluronic acid copolymer for vesicoureteral reflux.

PURPOSE: Dextranomer/hyaluronic acid copolymer is a novel substance that has favorable properties for endoscopic treatment of vesicoureteral reflux. We assess the long-term efficacy and safety of this treatment of children. MATERIALS AND METHODS: Children 1 to 15 years old with grade III or greater vesicoureteral reflux were eligible for enrollment in our study. All patients received endoscopic treatment with dextranomer/hyaluronic acid copolymer and were scheduled to have a voiding cystourethrogram 3 and 12 months after implantation. Children with reflux grade III or greater after treatment received up to 2 more implantations, and those with persistent reflux were referred for open surgery. In some cases long-term clinical followup was accompanied by a late voiding cystourethrogram. RESULTS: A total of 228 patients received endoscopic treatment. The efficacy population was comprised of 221 children, including 67 who received 2 and 8 who received 3 implantations. Endoscopic treatment was performed without complications in all cases. Patients were followed clinically for 2 to 7.5 years (mean 5). On the last voiding cystourethrogram 68% of patients had a positive response (grade I or less) and 81% had no dilating reflux. The corresponding results for treated ureters were 75% and 85%, respectively. Only 27 (12%) patients were referred for open surgery. A late voiding cystourethrogram was performed in 49 patients 2 to 5 years after treatment. Of the ureters free of reflux (grade 0) 3 to 12 months after treatment 96% remained free of dilating reflux. Adverse events occurred in association with implantation in only 2% of patients, although urinary tract infection subsequently developed in 8%. CONCLUSIONS: Endoscopic treatment with dextranomer/hyaluronic acid copolymer was effective and well tolerated in children with vesicoureteral reflux. Long-term followup indicated that there was no deterioration in patients responding positively to treatment.

Adolescent↗
PubMed2001

The overactive bladder in children: a potential future indication for tolterodine.

OBJECTIVE: To determine the safety, efficacy and pharmacokinetics of tolterodine in children with an overactive bladder. PATIENTS AND METHODS: Thirty-three children (20 boys and 13 girls, aged 5-10 years) with an overactive bladder and symptoms of urgency, frequency and/or urge incontinence were enrolled in an open, dose-escalation study. Patients were treated with oral tolterodine 0.5 mg (n = 11), 1 mg (n = 10) or 2 mg (n = 12) twice daily for 14 days. The primary safety endpoint was the change in residual urinary volume, as determined by ultrasonography. In addition, voiding diary variables (frequency and incontinence episodes) and pharmacokinetics were evaluated. Other safety endpoints included laboratory variables, electrocardiogram recordings and reported adverse events. RESULTS: There were no safety concerns in terms of the change in residual urinary volume for any of the three dosage groups; values were comparable with baseline after 2 weeks of treatment for all three dosages. Adverse events were reported by 20 patients (six on 0.5 mg, five on 1 mg, and nine on 2 mg). Most adverse events were not considered to be drug-related; of the 13 possibly related events, 10 occurred in those taking 2 mg. Headache was the most commonly reported adverse event. No serious adverse events were reported and there were no general safety concerns. There was an improvement in voiding diary variables in all treatment groups after 2 weeks of treatment, although the efficacy was greatest in those taking 1 mg and 2 mg. Pharmacokinetic findings were consistent with dose linearity over the range 0.5-2 mg. CONCLUSION: The results support the use of 1 mg twice daily as the optimal dose of tolterodine for treating children aged 5-10 years with an overactive bladder.

Administration, Oral↗
PubMed2001

Effect of thromboxane and nitric oxide blockade on renal blood flow increase during volume expansion in hydronephrotic rats.

OBJECTIVE: It has recently been found that hydronephrotic rats, despite low diuresis, show a significant increase in renal blood flow (RBF) during volume expansion. The present experiments were designed to evaluate the mechanisms underlying this phenomenon. MATERIAL AND METHODS: Three-week-old Sprague-Dawley rats underwent partial obstruction of the left ureter using the Ulm-Miller psoas groove technique. The effects on RBF were studied 3 weeks later under general anesthesia using real-time ultrasound flowmetry, first during normohydration and then during extracellular volume expansion, in both untreated animals, and after prior blockade of either thromboxane or nitric oxide. RESULTS: Significant hydronephrosis developed in all cases. RBF was normal under control conditions. During volume expansion RBF increased significantly in untreated experimental animals (mean 7.5%). In contrast to this finding, RBF remained unchanged during volume expansion in both the thromboxane and nitric oxide blockade groups. CONCLUSION: It is concluded that a thromboxane- and/or nitric oxide-dependent RBF redistribution takes place in hydronephrotic kidneys during volume expansion.

Animals↗
PubMed2001

Bladder capacity and renal concentrating ability in enuresis: pathogenic implications.

PURPOSE: We compared bladder volume and renal concentrating capacity in dry children and 2 distinct groups of children with enuresis to hypothesize about the pathogenesis of various types of enuresis. MATERIALS AND METHODS: A total of 55 dry children and 100 with enuresis underwent an overnight thirst provocation test to assess renal concentrating capacity and completed a 2-day voiding chart to assess functional bladder capacity. The enuretic children were subdivided into 27 desmopressin responders and 73 desmopressin nonresponders before study inclusion. RESULTS: The desmopressin responder group had lower average renal concentrating capacity +/-1 standard deviation than dry children and desmopressin responders (856 +/- 158 mOsm./kg. versus 939 +/- 147 and 962 +/- 151, respectively, p <0.05). Analogously average daytime urine production in the desmopressin responder group was greater than in dry children and desmopressin responders (22.2 +/- 10.2 ml./kg. body weight versus 15.4 +/- 7.3 and 15.3 +/- 7.2, respectively, p <0.01). Average functional bladder capacity expected for age was less in desmopressin nonresponders than in dry children and responders (52.2% +/- 19.9% versus 79.2% +/- 30.4% and 69.5% +/- 25.7%, respectively, p <0.001). CONCLUSIONS: Desmopressin responders produced larger amounts of less concentrated urine than the other children, while desmopressin nonresponders had smaller bladder capacity than the other groups. These results support the idea that enuretic children who respond favorably to desmopressin treatment have polyuria, whereas children with therapy resistant enuresis have detrusor hyperactivity.

Child↗
PubMed2001

Renal blood flow increase during volume expansion in hydronephrotic rats.

PURPOSE: We assessed the renal blood flow pattern in experimental hydronephrosis during normal hydration and extracellular volume expansion. MATERIALS AND METHODS: Partial obstruction of the left ureter was created in 3-week-old Sprague-Dawley rats by embedding the ureter in a psoas muscle groove. Moderate hydronephrosis without kidney weight reduction developed in all cases. The effects on renal hemodynamics were studied with real-time ultrasound flowmetry 3 weeks later during normal hydration and then during volume expansion. The degree of hydronephrosis was classified as mild, moderate or severe. RESULTS: Under baseline conditions renal blood flow was normal in mild and moderate hydronephrosis but low in severe hydronephrosis. During volume expansion renal blood flow increased significantly in all experimental animals (mean 14%) compared to that in controls, which remained unaffected or decreased (mean -3%). The flow increase was related to the degree of dilatation, which was 2% in mild, 13% in moderate and 44% in severe hydronephrosis when the groups were considered separately. CONCLUSIONS: A significant increase in renal blood flow proportional to the degree of hydronephrosis occurred as a result of volume expansion. This finding may be explained by a state of vasodilatation combined with a reduction in the filtration coefficient.

Animals↗
PubMed2000

Enuresis--background and treatment.

Nocturnal urinary continence is dependent on 3 factors: 1) nocturnal urine production, 2) nocturnal bladder function and 3) sleep and arousal mechanisms. Any child will suffer from nocturnal enuresis if more urine is produced than can be contained in the bladder or if the detrusor is hyperactive, provided that he or she is not awakened by the imminent bladder contraction. Urine production is regulated by fluid intake and several interrelated renal, hormonal and neural factors, foremost of which are vasopressin, renin, angiotensin and the sympathetic nervous system. Detrusor function is governed by the autonomic nervous system which under ideal conditions is under central nervous control. Arousal from sleep is dependent on the reticular activating system, a diffuse neural network that translates sensory input into arousal stimuli via brain stem noradrenergic neurons. Disturbances in nocturnal urine production, bladder function and arousal mechanisms have all been firmly implicated as pathogenetic factors in nocturnal enuresis. The group of enuretic children are, however, pathogenetically heterogeneous, and two main types can be discerned: 1) Diuresis-dependent enuresis - these children void because of excessive nocturnal urine production and impaired arousal mechanisms. 2) Detrusor-dependent enuresis - these children void because of nocturnal detrusor hyperactivity and impaired arousal mechanisms. The main clinical difference between the two groups is that desmopressin is usually effective in the former but not in the latter. There are two first-line therapies in nocturnal enuresis: the enuresis alarm and desmopressin medication. Promising second-line treatments include anticholinergic drugs, urotherapy and treatment of occult constipation.

Arousal↗
PubMed1999

Prevalence of postmenopausal symptoms in two age groups of elderly women in relation to oestrogen replacement therapy.

A cross-sectional study of the whole female population of ages 71 and 81 years in a defined part of Sweden was undertaken to investigate the prevalence of oestrogen treatment and postmenopausal symptoms. A questionnaire was mailed to 2245 women, of whom 1084 (87%) aged 71 years and 611 (62%) aged 81 years left evaluable responses. Of the responding 71- and 81-year-old women 25 and 16%, respectively were receiving oestrogen, and 4 and 2% of all women of the respective age groups were on systemic treatment. Nearly half of all the women reported urinary incontinence, which was considerate for approximately half of these women. Five and 11% of the respective age groups had experienced more than two urinary tract infections (RUTI) in the last year. RUTI had occurred both in the oestrogen-treated group and in the non-treated group. Vegetative symptoms were still encountered among these elderly women. Previous fractures were frequent, being experienced after menopause by 29 and 39% of the 71- and 81-year-old women respectively. Thirty-five and 39% of the women in respective age group had sought medical help for postmenopausal symptoms. Of the women with moderate, severe or unbearable urinary incontinence, 60 and 66% of the respective age groups had sought medical help. In only few of the totals of women on oestrogen had the treatment a complete effect. Only 2 and 1% of all women in respective age group had been offered and undergone surgery for their urinary incontinence.

Aged↗
PubMed1999

Desmopressin resistant enuresis: pathogenetic and therapeutic considerations.

PURPOSE: We tested the role of the bladder in the pathogenesis of desmopressin resistant enuresis by evaluating the influence of urine production on the timing of the enuretic event and the response to anticholinergic medication. MATERIALS AND METHODS: We gave 33 children with monosymptomatic nocturnal enuresis resistant to the standard 0.4 mg. oral dose of desmopressin 0.4 and 0.8 mg. desmopressin and placebo tablets for 5 nights each in a double-blind crossover fashion. The time of enuresis or nocturia was documented. All 9 children who had at least 1 dry treatment period during the randomized portion of the study then received open label treatment with 0.8 mg. desmopressin. Nonresponders to this regimen and the remainder of the children were offered anticholinergic treatment. RESULTS: Average time between bedtime and voiding was 5.0, 5.6 and 5.0 hours during the nights with placebo, and 0.4 and 0.8 mg. desmopressin, respectively (p = 0.12). Of the 9 children subsequently treated with 0.8 mg. desmopressin 5 became completely dry. Of the remaining 28 children given anticholinergic treatment 20 responded. CONCLUSIONS: Antidiuresis does not delay the enuretic event in children with desmopressin resistant enuresis. This finding and the favorable response to anticholinergic medication favor the hypothesis that these children have nocturnal bladder instability. A subgroup of enuretic children responds to high but not normal doses of desmopressin.

Adolescent↗
PubMed1999

Injectable dextranomer-based implant: histopathology, volume changes and DNA-analysis.

OBJECTIVE: To study the tissue reaction in and around the implant, the changes in implant volume and the DNA profile of the invading cells when a new substance, dextranomers in sodium hyaluronan solution (DiHA), was injected into experimental animals. MATERIALS AND METHODS: Nine pigs were followed up from 2 weeks to 3.5 months and 34 rats were followed up from 3 weeks to 16 months after injection of DiHA into the bladder in pigs and into the subcutaneous tissue in rats. Histopathological analysis was performed in 16 pig and 63 rat implants. In 31 of the rat implants the DNA profile was analysed. Changes in implant volume over time were estimated in 51 rat implants during the period up to 12 months after implantation. RESULTS: Histologically, in the early phases the area within and around the implant was fairly rich in cells, predominantly fibroblasts, inflammatory cells and giant cells of the foreign body type. Later in the process an increase in extracellular matrix around the microspheres and ingrowth of blood vessels was seen. No tissue necrosis or significant eosinophilia was observed around the implants. DNA measurements by flow cytometry revealed no aneuploid cells. There was a decrease in implant volume by 23% over a period of 12 months. CONCLUSIONS: DiHA does not induce any major tissue changes in and around the implants. No DNA changes were observed during the study period of 16 months. DiHA seem to be a safe and suitable injectable substance with good tissue-augmenting properties.

Animals↗
PubMed1999

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.

Biocompatible Materials↗