Urothelium-preserving augmentation cystoplasty covered with a peritoneal flap

Use of an acellular collagen-elastin matrix to support bladder regeneration in a porcine model of peritoneocystoplasty

Introduction

Bladder reconstruction without using the intestine remains a challenge to this day despite the development of new biomaterials and cell cultures. Human bladder engineering is merely anecdotic, and mostly in vitro and animal studies have been conducted.

Material and methods

In our study using a porcine model, we performed a bladder augmentation using an autologous parietal peritoneum graft (peritoneocystoplasty) and determined whether the attachment of an acellular collagen-elastin matrix (Group 1) or lack of (Group 2) had better histologic and functional results. Thus far, peritoneocystoplasty has rarely been performed or combined with a biomaterial.

Results

After 6 weeks, we observed different degrees of retraction of the new bladder wall in both groups, although the retraction was lower and the histological analysis showed more signs of regeneration (neoangiogenesis and less fibrosis) in Group 1 than when compared with Group 2. No transitional cells were found in the new bladder wall in any of the groups, and no differences were observed in the functional test results.

Conclusions

Performing a peritoneocystoplasty is an easy and safe procedure. The data supports the benefit of an acellular collagen–elastin matrix to reinforce bladder regeneration. However, in our study we observed too much retraction of the new wall and the histologic results were not acceptable to consider it an appropriate cystoplasty technique.

Alternatives to conventional enterocystoplasty in children: a critical review of urodynamic outcomes

Alternatives to conventional enterocystoplasty have been developed in order to avoid the most common complications derived from contact of the urine with intestinal mucosa. In this article critically we review the literature on the topics: ureterocystoplasty, detrusorectomy, detrusorotomy, seromuscular gastroenterocystoplasty, use of off the shelf biomaterials, and bladder augmentation by bioengineering. Recognizing the difficulty of deciding when a child with a history of posterior urethral valves requires and augmentation and that the development of a large megaureter in cases of neurogenic dysfunction represents a failure of initial treatment, we conclude that ureterocystoplasty can be useful in selected cases when a large dilated ureter is available. Seromuscular colocystoplasty lined with urothelium (SCLU) has been urodynamically effective in several series when the outlet resistance is high and no additional intravesical procedures are necessary. Seromuscular gastrocystoplasty lined with urothelium seems to offer no distinct advantages and involves a much more involved operation. The use of seromuscular segments without urothelial preservation, with or without the use of an intravesical balloon has been reported as successful in two centers but strict urodynamic evidence of its effectiveness is lacking. The published evidence argues strongly against the use of detrusorectomy or detrusorotomy alone because of the lack of significant urodynamic benefits. Two recent reports discourage the use of small intestinal submucosa patches because of a high failure rate. Finally, research into the development of a bioengineered bladder constructed with cell harvested from the same patient continues but is fraught with technical and conceptual problems. In conclusion of the methods reviewed, only ureterocystoplasty and SCLU have been proven urodynamically effective and reproducible.

Promising long-term outcome of bladder autoaugmentation in children with neurogenic bladder dysfunction

PURPOSE

We evaluated the long-term outcome of bladder autoaugmentation in children with neurogenic bladder dysfunction.

MATERIALS AND METHODS

Data were compiled from the records of 25 children with a median age of 9.3 years (range 0.9 to 14.2) who underwent detrusor myotomy between 1992 and 2008. All patients were diagnosed with small bladder capacity, low compliance and high end filling pressures, and were unresponsive to clean intermittent catheterization and anticholinergics.

RESULTS

Median followup was 6.8 years (range 0.1 to 15.6). Median postoperative bladder capacity was unchanged or decreased to 95 ml (range 25 to 274) during the first 3 months compared to a median preoperative capacity of 103 ml (14 to 250). At 5 months postoperatively median bladder capacity increased significantly to 176 ml (range 70 to 420, p<0.01). This increase remained significant during the rest of followup. Median bladder compliance doubled after 1 year to 10 ml/cm H2O (range 1 to 31, p<0.05) compared to the preoperative level, and further increased to 17 ml/cm H2O (5 to 55) at 5 years (p<0.05). Median maximal detrusor pressure was 43 cm H2O (range 8 to 140) preoperatively. This value decreased significantly postoperatively (p<0.01) and at final followup it was 26 cm H2O (range 6 to 97). Kidney function developed normally in all patients except 1 with persistent uremia. Reflux was alleviated in 7 of 9 cases. Of the patients 18 became continent on clean intermittent catheterization.

CONCLUSIONS

Bladder autoaugmentation in children with neurogenic bladder dysfunction offers, after a transient decrease in bladder capacity, a long lasting increase in capacity and compliance, while the end filling pressure decreases.

Urinary bladder auto augmentation using INTEGRA and SURGISIS: an experimental model

OBJECTIVE

We present our experience with an experimental urinary bladder auto augmentation model using SURGISIS and INTEGRA (collagen layer) in comparison with seromuscular enterocystoplasty. The aim of the study was to evaluate the change in compliance and elasticity of the urinary bladder.

MATERIALS AND METHODS

Eighteen lambs were divided into three different groups. Auto augmentation was performed using the seromuscular layer of small bowel, SURGISIS or the collagen layer of INTEGRA. After 3 months of the initial procedure, the lambs were re-operated, the bladder compliance was measured and the urinary bladder was submitted for histological examination and assessment of elasticity. The lambs were euthanized.

RESULTS

The postoperative period was uneventful in 17 lambs except for intestinal obstruction in one lamb from the seromuscular enterocystoplasty group. A statistically significant difference in compliance was observed with SURGISIS and the INTEGRA. Histologically, there was neovascularization in all the specimens from the SURGISIS and INTEGRA groups with the presence of fibrosis in the SURGISIS group. The INTEGRA group showed better elastic properties than the SURGISIS.

CONCLUSIONS

Urinary bladder auto augmentation using the collagen layer of INTEGRA showed better functional and histological results when compared with SURGISIS and demucosalized enterocystoplasty in the present model.

Chapitre C-2 B - Traitement de l’hyperactivité détrusorienne neurologique : détrusoromyomectomie

This article reviews the technical principles and results of bladder auto-augmentation by detrusor myomectomy. This technique has been regularly presented since the 1970s as an alternative to enterocystoplasty, especially in children. This review of the literature demonstrates that the current results of bladder auto-augmentation are highly controversial. Most series of patients with neurogenic bladder with a relatively long mean follow-up (about 6 years) conclude on the inefficacy of this technique on both symptoms and objective parameters (urodynamic results). It therefore seems difficult to recommend bladder auto-augmentation by detrusor myomectomy as a reliable alternative to enterocystoplasty, which remains the reference technique.

Bladder augmentation without integration of intact bowel segments: critical review and future perspectives

PURPOSE

We evaluated the long-term results of autoaugmentation in the pediatric age group and summarized technical adaptations, experimental options and future perspectives for treating these patients.

MATERIALS AND METHODS

A directed MEDLINE literature review was performed to assess different techniques and alternative options in autoaugmentation procedures. Of 150 studies 49 in the subgroup with the longest duration of followup to show the long-term outcome of the autoaugmentation procedures were chosen for this review. Information gained from these data was reviewed and new perspectives were summarized.

RESULTS

Enterocystoplasy is an effective mode of therapy with acceptable morbidity and satisfactory clinical results, although it is major intraperitoneal surgery with various complications and patients need prolonged convalescence to adapt to these surgical procedures. On the other hand, patient selection seems to be the most crucial step for the success of autoaugmentation procedures because the clinical outcome does not appear to be durable.

CONCLUSIONS

Achievement of better compliance after autoaugmentation procedures seems to be less pronounced and of shorter duration than that of conventional enterocystoplasty. On the other hand, the low morbidity and lack of side effects of bowel integration into the urinary tract are the definite advantages of this technique. It is the responsibility of the physician to determine the balance between the limited efficacy of the procedures vs the definite advantages. Although functionally improved parameters are obtained in tissue engineered autologous bladders, there is an absolute need for additional studies before this challenging technique could be applied widely.

Bladder wall replacement by tissue engineering and autologous keratinocytes in minipigs

OBJECTIVE

To develop a tissue-engineered bladder wall replacement with autologous cells and a biodegradable scaffold, as whenever there is a lack of native urological tissue the bladder is reconstructed with different bowel segments, which has inevitable complications.

MATERIAL AND METHODS

Skin biopsies were taken from six minipigs, and primary fibroblast and keratinocyte cell cultures established. A partial resection of the urinary bladder was reconstructed by a cell-seeded scaffold covered with completely differentiated epithelium and supported by a mucosa-free pedicled ileum graft. Each pig was assessed urodynamically and by cystography before operation and every month until explantation; the pigs were killed at 1, 2 and 3 months after augmentation. Control groups (of six pigs each) with bladder augmentation with complete or denuded ileum were used. The bladders were assessed histologically and by distensibility measurements

RESULTS

The differentiated keratinocyte epithelium was still present on the reconstructed bladder wall after 3 months. The overall shrinkage rate was 6.5%. The engineered bladder wall had lower distensibility than the native one. The inflammatory reaction present initially had disappeared after 3 months.

CONCLUSIONS

The implanted, tissue-engineered substitution of the bladder wall is not only a bridging graft, but also a complete reconstruction. With this model, extended bladder wall substitution seems feasible and should be investigated in further studies.

Detrusor myectomy: long-term results with a minimum follow-up of 2 years

OBJECTIVES

To assess the long-term results of detrusor myectomy, which has obvious theoretical advantages over enterocystoplasty for refractory detrusor overactivity (DO), and for which the early results have been encouraging.

PATIENTS AND METHODS

The medical records were reviewed of 30 consecutive patients (median age 33 years, range 10-62) who had a detrusor myectomy between November 1992 and April 2002 in our unit. Twenty-four patients (80%) had idiopathic DO (six males and 18 females) and six (20%) had neurogenic DO (four males and two females). The median (range) follow-up was 79 (28-142) months. All patients were confirmed to have DO on urodynamics before surgery and 26 (87%) had urodynamics afterward.

RESULTS

Nineteen (79%) of those with idiopathic DO and two with neurogenic DO showed a continued overall improvement. The cystometric capacity improved in 80% of patients after surgery, whilst the detrusor pressure at maximum flow and the bladder contractility index decreased in 60% and 78% of the patients, respectively. Ten patients (45%) had to start clean intermittent self-catheterization after surgery.

CONCLUSIONS

Detrusor myectomy is successful in approximately 80% of patients with idiopathic DO, although detrusor contractility is affected in most and almost half of the patients required clean intermittent self-catheterization afterward. This procedure should be offered as an alternative to enterocystoplasty as it is less morbid and does not preclude subsequent surgery if required. However, further evaluation of this technique is required in neuropathic patients.

Detrusorectomy for Neuropathic Bladder in Patients with Spinal Dysraphism

PURPOSE

We assess the outcome of detrusorectomy in 35 patients with spina bifida who were incontinent due to poor bladder volume or poor compliance.

MATERIALS AND METHODS

Of 51 patients requiring bladder augmentation 35 underwent detrusorectomy. In 3 patients ileocystoplasty was later performed as a secondary procedure because of failure of the detrusorectomy.

RESULTS

A total of 35 patients (17 males, 18 females) underwent detrusorectomy. Mean patient age at operation was 9.9 years (range 0.4 to 17.8). Mean followup was 4.9 years (range 1 to 10.5). A continent catheterizable vesicostomy was constructed in 14 patients and ureteral reimplantation was performed in 8. Twenty-five patients also underwent sling and/or Burch cystourethropexy during detrusorectomy, of whom 19 are continent and 5 have some leakage between clean intermittent catheterizations. In 1 girl the sling procedure was not successful, and she was subsequently treated with bladder neck closure. Bladder compliance after operation was improved in 9 cases and unchanged in 10. Of the 16 patients in whom compliance was already acceptable before the operation and was unchanged after detrusorectomy 7 were able to stop antimuscarinic therapy. Compliance became poor in 4 cases, of which 3 required ileocystoplasty. Bladder volume (as a percentage of normal volume for age) was increased after detrusorectomy in 13 patients, unchanged in 11 and decreased in 11. Complications of detrusorectomy included bladder leakage in 2 cases. One patient needed a laparotomy because of urinary ascites shortly after the operation.

CONCLUSIONS

Detrusorectomy may be combined with other procedures such as ureteral reimplantation, slingplasty and continent vesicostomy. Of 35 treated patients compliance improved in 16 (46%),volume improved in 13 (37%), 3 had no change in parameters, and 3 had a slight decrease in volume and compliance. Four patients had poor results, of whom 3 needed a secondary ileocystoplasty. Therefore, it may be concluded that detrusorectomy is a safe and probably useful procedure for improvement of bladder volume and compliance in patients with neurogenic bladder dysfunction, and may obviate the need for ileocystoplasty in a limited number of patients.

Autoaugmentation by Detrusor Myotomy: Its Lack of Effectiveness in the Management of Congenital Neuropathic Bladder

PURPOSE

We present our long-term results in 17 patients with myelomeningocele undergoing autoaugmentation by vesicomyotomy.

MATERIALS AND METHODS

Surgery was performed from 1990 to 1994 on 17 patients with neurogenic bladder due to spinal dysraphism. Indications for autoaugmentation included upper tract deterioration and/or incontinence secondary to hypperreflexia, hypocompliance or low bladder volume. All patients had failed to respond to conservative medical and pharmacological treatments. Median patient age at surgery was 10.2 years (range 2.2 to 13.2). Outcomes were evaluated retrospectively according to changes in upper tract status, continence and urodynamic parameters. Median clinical and urodynamic followup is 75 months (range 4 to 126).

RESULTS

Progressive hydronephrosis developed in 5 patients, which required subsequent enterocystoplasty in 4. Of 13 patients 8 (62%) remain incontinent. Of the 17 cases 12 (71%) were considered clinical failures on the basis of upper tract deterioration and/or ongoing incontinence. There were few clinically significant improvements in urodynamic parameters, as 14 of 15 cases (93%) were considered urodynamic failures on the basis of persistent hypocompliance and/or less than expected gains in safe bladder capacity with somatic growth.

CONCLUSIONS

Although short-term reports of autoaugmentation have been promising, they do not appear durable. This procedure cannot be endorsed for the management of congenital neuropathic bladder.

Autoaugmentation peritoneocystoplasty in a sheep model

OBJECTIVE

To report our experience with autoaugmentation peritoneocystoplasty (AAPC) in a sheep model, and to compare the results with autoaugmentation gastrocystoplasty (AAGC) in a sheep model and in paediatric patients.

MATERIALS AND METHODS

Ten 6-month-old male lambs underwent bladder augmentation by detrusorotomy. A flap of parietal peritoneum, dissected from the anterior abdominal wall, was used to cover the bladder mucosa. The sheep were evaluated by urodynamics 6 months after surgery. Bladder compliance (bladder volume/intravesical pressure) was calculated for the bladder capacity at leakage. The urodynamic results were compared with age-matched control sheep and with 12 sheep that had undergone AAGC; the results were assessed using the Mann-Whitney U-test.

RESULTS

In two of the 10 sheep, bladder volumes after AAPC increased by > 100%, although for the group, the mean (range) bladder volume after augmentation, at 159 (42-261) mL, was not significantly different from that before surgery (mean 143 mL). Bladder volumes after AAPC were not significantly different from those in the control sheep (mean 205 mL) but were significantly less than in the AAGC group (mean 317 mL; P < 0.05). Bladder compliance at leak capacity in the AAPC group (mean 5.4 mL/cmH2O) was also not significantly different from the controls (mean 9.1 mL/cmH2O), but was lower than the in the AAGC animals (median 14.6 mL/cmH2O; P < 0.05).

CONCLUSIONS

AAPC in a sheep model does not result in a reliable increase in bladder volume or compliance. The volume and compliance are inferior to those found in bladders augmented by AAGC.