A new approach to bladder augmentation in children: seromuscular enterocystoplasty

Surgical outcomes of bladder augmentation: A comparison of three different augmentation procedures

BACKGROUND

Augmentation cystoplasty is indispensable in many pediatric diseases, especially neurogenic bladder. Various methods and materials are used to augment the bladder, and these methods are associated with different shortcomings and complications.

AIM

The present study reported the mid-term outcomes of patients undergoing various bladder augmentation procedures in a single institution, and assessed whether seromuscular cystoplasty lined with urothelium (SCLU) provided better urodynamic results than auto-augmentation (AA).

METHODS

A retrospective review of 96 patients undergoing various augmentation methods between 2003 and 2018 was performed. The patients were divided into three groups according to the type of augmentation, and their outcomes were compared. All patients developed neurogenic bladder due to myelomeningocele or sacrococcygeal teratoma. The clinical data of all patients were collected.

RESULTS

The mean ages at surgery in the three groups (standard cystoplasty [SC], SCLU, AA) were 10.8, 7.5, and 4.8 years, respectively, with mean follow-ups of 36, 61, and 36 mo, respectively. The mean preoperative and postoperative bladder capacities of the SC, SCLU, and AA groups were 174 ± 11.7 vs. 387 ± 13.7 (P < 0.0001), 165 ± 12.2 vs. 240 ± 14.7 (P = 0.0002), and 138 ± 16.7 vs. 181 ± 9.9 (P = 0.0360), respectively. Compared with the AA group, the SCLU procedure did not have better postoperative urodynamic parameters. Incontinence was reduced in most patients. The mean times of clean intermittent catheterization per day in the SC, SCLU, and AA groups were 5.6, 7.8, and 8.2, respectively. The main complications of the SC group were recurrent urinary tract infections (8%) and bladder calculi (6%). Re-augmentation was done in patients in the SCLU (8) and AA (3) groups.

CONCLUSION

SC provided sufficient bladder capacity and improved compliance with acceptable complications. After AA and SCLU, the patients acquired limited increases in bladder capacity and compliance with a high rate of re-augmentation. Compared with AA, SCLU did not yield better postoperative urodynamic parameters.

Outcomes of seromuscular bladder augmentation versus standard ileocystoplasty: A single institution experience over 14 years

INTRODUCTION

Ileocystoplasty is the standard technique used for bladder augmentation, and has been used widely for decades. However, it is known to be associated with complications such as stone formation, mucus production, metabolic acidosis, urinary tract infections, intestinal obstruction, and a long-term risk of bladder cancer. Seromuscular bladder augmentation (SMBA) is an alternative to the standard ileocystoplasty, and has been associated with a lower incidence of bladder stones. Few reports have been published on intermediate outcomes of SMBA. Herein, we report long-term outcomes of SMBA from a single institution compared with standard ileocystoplasty.

METHODS

After Institutional Review Board approval, a retrospective chart review of all patients who underwent bladder augmentation at our institution over a 14-year period was performed. The status of patients after SMBA (10 patients) was compared according to age, sex, and diagnosis with patients who underwent traditional ileocystoplasty (30 patients). Parameters such as demographic information, pre- and postoperative bladder capacity as assessed by urodynamic studies, urinary tract infections (UTIs), bladder calculi, incontinence, need for secondary surgical procedures, and spontaneous bladder perforation were compared in the two groups. All the patients were on a clean intermittent catheterization (CIC) regimen.

RESULTS

Over the study period, 10 patients underwent SMBA and 30 patients (according to age, sex, and diagnosis) underwent standard ileocystoplasty; the average age at surgery was 10.3 and 10 years respectively, with a mean follow up of 6.7 years in the SMBA group and 6 years in the ileocystoplasty group. There were no statistically significant differences in the rate of UTIs, urinary incontinence, subsequent surgery, or spontaneous bladder perforation. The mean bladder capacity increased significantly for both groups as assessed by pre- and postoperative urodynamic studies, although the difference in the rate of bladder calculi between the two groups (0 [0%] vs. 8 [27%], p = 0.06) did not reach statistical significance (Table).

CONCLUSIONS

SMBA is safe and efficacious and may result in a lower rate of stone formation than standard ileocystoscopy. SMBA should be considered as a viable alternative to standard ileocystoplasty.

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.

Prerequisite for successful surgical outcome in urothelium lined seromuscular colocystoplasty

PURPOSE

Urothelium lined seromuscular colocystoplasty is an ideal method of augmentation cystoplasty that avoids various complications caused by the use of gastrointestinal segments. We reviewed the long-term outcomes using this technique at a single institution.

MATERIALS AND METHODS

We retrospectively analyzed 34 patients who underwent urothelium lined seromuscular colocystoplasty between January 1996 and December 2007. A total of 33 patients, excluding 1 who had previously undergone artificial urinary sphincter implantation, were included in the study. Changes in urodynamic parameters, duration of anticholinergic use, incontinence and surgical complications were analyzed.

RESULTS

Mean±SD age at surgery was 10.0±5.7 years (range 3.0 to 26.0) and duration of followup was 6.0±2.3 years (2.7 to 13.4). A total of 17 patients (51.5%) underwent simultaneous anti-incontinence surgery and urothelium lined seromuscular colocystoplasty. Mean bladder capacity increased by a factor of 2.96 and mean percentage of expected bladder capacity for age increased by a factor of 1.96 postoperatively. Of patients who underwent anti-incontinence surgery 4 of 10 whose abdominal leak point pressure was less than 40 cm H2O required additional surgery, whereas none whose abdominal leak point pressure was 40 to 60 cm H2O required reoperation. Two of 16 patients who did not undergo anti-incontinence surgery eventually required continence surgery. A total of 13 patients (39.4%) were able to discontinue anticholinergics at 47.3 months postoperatively. There were no bladder perforations, bowel obstructions or metabolic abnormalities.

CONCLUSIONS

Urothelium lined seromuscular colocystoplasty can be primarily considered in patients without prior bladder mucosal injury. Constant high bladder outlet pressure to facilitate adhesion of bladder mucosa and seromuscular patch is critical for the best results. We recommend abdominal leak point pressure 60 cm H2O or less as an indication for simultaneous anti-incontinence surgery and urothelium lined seromuscular colocystoplasty.

Determinants of success and failure of seromuscular colocystoplasty lined with urothelium

PURPOSE

Seromuscular colocystoplasty lined with urothelium is a method of bladder augmentation that avoids incorporating intestinal mucosa into the urinary tract. Others have reported a repeat augmentation rate of 23%. We analyzed the results in 20 patients who underwent the procedure, as performed by one of us (RG), at 3 institutions.

MATERIALS AND METHODS

After receiving institutional review board approval we retrospectively reviewed the charts of all patients operated on since 1998. Preoperative and postoperative bladder capacity at 30 cm H(2)O, expressed as the percent of expected capacity for age using the equation, bladder capacity in ml = (age +1) x 30, as well as prior, concomitant and subsequent bladder or bladder neck procedures, continence and the need for repeat augmentation were recorded.

RESULTS

There were 20 patients, including 7 females, with a mean age at surgery of 9 years and a mean followup of 53 months. All patients had neurogenic bladder dysfunction. An artificial urinary sphincter was implanted at the time of seromuscular colocystoplasty in 10 patients, preoperatively in 6 and postoperatively in 1. A sling was used in 3 females. Patients were divided into 2 groups. The 15 group 1 patients underwent no concomitant procedure in the bladder and the 5 in group 2 underwent creation of a continent channel at seromuscular colocystoplasty. There were no failures of augmentation in group 1, in which bladder capacity increased from 60% of that expected for age to 100%. All patients were continent. Three of the 5 patients in group 2 required repeat augmentation.

CONCLUSIONS

Seromuscular colocystoplasty lined with urothelium has proved to be an effective method to augment the bladder in patients who have an artificial urinary sphincter or who undergo simultaneous artificial urinary sphincter implantation. We do not recommend constructing a continent catheterizable channel at the time of seromuscular colocystoplasty lined with urothelium.

Comparison of traditional enterocystoplasty and seromuscular colocystoplasty lined with urothelium

OBJECTIVE

To evaluate long-term outcomes between various methods of augmentation cystoplasty.

METHODS

A retrospective analysis was performed of patients undergoing seromuscular colocystoplasty lined with urothelium (SCLU, n=26), and their outcomes compared to a similar population of patients in the same institution who had received traditional forms of bladder augmentation (colocystoplasty and ileocystoplasty, n=32). Measurements included efficacy of the procedure in increasing bladder capacity and achieving urinary continence, and the need of subsequent surgery for complications.

RESULTS

There was no statistically significant difference in achieved bladder capacity, subjective urinary continence and the rates of subsequent surgery for stones, vesicoureteral reflux, augment failure, bladder neck continence and catheterizable channel. None of the patients in the SCLU group had spontaneous perforation or small bowel obstruction.

CONCLUSION

Patients with SCLU are at decreased risk for bowel obstruction and spontaneous perforation, but are not devoid of other long-term complications including bladder stones, vesicoureteral reflux and augment failure. Most of the risks and benefits of augmentation cystoplasty performed using ileum, colon, or SCLU appear similar.

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.

Urothelial ingrowth over demucosalized gastrocystoplasty: an experimental study

OBJECTIVE

To evaluate histopathologically the ingrowth of urothelium over a demucosalized gastric flap used for augmentation, as such flaps increase the capacity of the bladder if the urothelium can cover the seromuscular patch.

MATERIALS AND METHODS

The study included eight male dogs; the urinary bladder was widely divided at its dome anteroposteriorly to receive a seromuscular gastric flap, sutured to the edges of the urinary bladder. Before and 1 month after surgery the changes in bladder capacity and pressure were recorded, and urothelial ingrowth assessed histopathologically.

RESULTS

Two of the eight dogs died; the increase in mean bladder capacity in the remaining dogs was 20% and the decrease in mean intravesical pressure 34%. Gross pathological examination of the urinary bladder showed good 'take' of the gastric flap by the urinary bladder. Histopathologically, there was good healing of the flap, active ingrowth of urothelium, and no mucosal re-growth.

CONCLUSION

Bladder augmentation with a demucosalized gastrocystoplasty allows the creation of a large compliant urinary bladder with few complications caused by the incorporation of the enteric or gastric epithelium into the urinary bladder. The stomach has a rich blood supply, allowing the harvesting of a well-vascularized flap, and urothelial ingrowth over this flap in the present study was significant.

Further experience with seromuscular colocystoplasty lined with urothelium

PURPOSE

We report our continuing experience with seromuscular colocystoplasty lined with urothelium. This procedure is designed to preserve the urothelium and potentially decrease the incidence of complications associated with standard bladder augmentation.

MATERIALS AND METHODS

We retrospectively reviewed the charts of 32 patients who underwent seromuscular colocystoplasty lined with urothelium between April 1994 and July 1999. Data were collected on patient demographics, surgical indications, previous and adjunctive surgical procedures, preoperative and postoperative urinary continence, upper urinary tract changes, urodynamic parameters, surgical complications and histological findings.

RESULTS

Mean patient age at surgery plus or minus standard deviation was 11.1 +/- 4.8 years. Mean followup was 1.6 +/- 1 years. A mean of 1.5 +/- 0.9 years postoperatively urodynamic studies available in 28 cases showed that total and safe bladder capacity increased by 1.8 and 2.4-fold, respectively. Continence was achieved in 71% of patients after the initial procedure, increasing to 81% after secondary procedures. Hourglass deformity developed in 7 cases (22%), augmentation failed in 4 (12.5%) and there were bladder calculi in 2 (6%). New onset or increased hydronephrosis and reflux were present in 6 of 62 (10%) and 9 of 60 (15%) evaluated renal units, respectively. Of the 7 interpretable biopsies 5 revealed various degrees of repeat colonic mucosal growth. There was no bladder perforation or metabolic abnormalities, and mucous production was not clinically significant.

CONCLUSIONS

Seromuscular colocystoplasty lined with urothelium is a viable alternative to standard bladder augmentation. The 2 procedures have a similar overall complication rate. Comparatively there appears to be a low incidence of bladder calculi, mucous production has not been clinically significant, metabolic disturbances have not developed and perforation has not occurred during short-term followup. We are enthusiastic about this technique and continue to apply it in select patients.