Mucosal Violations and Their Effect on Successful Bladder Neck Closure in Cloacal Exstrophy

BACKGROUND

Cloacal exstrophy (CE) is rare and challenging to reconstruct. In the majority of CE patients voided continence cannot be achieved and so patients often undergo bladder neck closure (BNC). Prior mucosal violations (MVs), a surgical event when the bladder mucosa was opened or closed, significantly predicted failed BNC in classic bladder exstrophy with an increased likelihood of failure after 3 or more MVs. The aim of this study was to assess predictors for failed BNC in CE.

METHODS

CE patients who underwent BNC were reviewed for risk factors for failure including osteotomy use, successful primary closure, and number of MVs. Chi-squared and Fisher's exact tests were used for comparing baseline characteristics and surgical details.

RESULTS

Thirty-five patients underwent BNC. Eleven patients (31.4%) failed BNC including a vesicoperineal fistula in nine, vesicourethral and vesicocutaneous fistula in one each. The fistula rate in patients with 2 or more MVs was 47.4% (p = 0.0252). Two patients subsequently developed a vesicocutaneous fistula after undergoing repeated cystolithotomies. A rectus abdominis or gracilis muscle flap were used to close the fistula in 11 and 2 patients, respectively.

CONCLUSIONS

MVs have a greater impact in CE with an increased risk of failed BNC after 2 MVs. CE patients are most likely to develop a vesicoperineal fistula while a vesicocutaneous fistula is more likely after repeat cystolithotomy. A prophylactic muscle flap should be considered at time of BNC in patients with 2 or more MVs.

LEVELS OF EVIDENCE

Prognosis Study, Level III.

The impact of repeated bladder surgery on successful bladder neck closure in classic bladder exstrophy: The role of mucosal violations

INTRODUCTION

Restoration of genitourinary anatomy with functional urinary continence is the reconstruction aim is the exstrophy-epispadias complex (EEC). In patients who do not achieve urinary continence or those who are not a candidate for bladder neck reconstruction (BNR), bladder neck closure (BNC) is considered. Interposing layers including human acellular dermis (HAD) and pedicled adipose tissue are routinely placed between the transected bladder neck and distal urethral stump to reinforce the BNC and minimize failure due to fistula development from the bladder.

OBJECTIVE

The aim of this study was to review classic bladder exstrophy (CBE) patients who underwent BNC to identify predictors of BNC failure. Specifically, we hypothesize that increased operations on the bladder urothelium leads to a higher rate of urinary fistula.

STUDY DESIGN

CBE patients who underwent BNC were reviewed for predictors of failed BNC which was defined as bladder fistula development. Predictors included prior osteotomy, interposing tissue layer use and number of previous bladder mucosal violations (MV). A MV was defined as a procedure when the bladder mucosa was opened or closed for: exstrophy closure(s), BNR, augmentation cystoplasty or ureteral re-implantation. Predictors were evaluated using multivariate logistic regression.

RESULTS

A total of 192 patients underwent BNC of which 23 failed. Patients were more likely to develop a fistula with a wider pubic diastasis at time of primary exstrophy closure (4.4 vs 4.0 cm, p=0.0016), have failed exstrophy closure (p=0.0084), or have 3 or more MVs before BNC (p=0.0002). Kaplan-Meier analysis of fistula-free survival after BNC, demonstrated an increased fistula rate with additional MVs (p=0.0004, Figure 1). MVs remained significant on multivariate logistic regression analysis with a per-violation odds ratio of 5.1 (p<0.0001). Of the 23 failed BNC's, 16 were surgically closed including 9 using a pedicled rectus abdominis muscle flap which was secured to the bladder and pelvic floor.

CONCLUSION

This study conceptualized MVs and their role in bladder viability. Increased MVs confer an increased risk of failed BNC. When considering BNC, CBE patients with 3 or more prior MVs may benefit from a pedicled muscle flap, in addition to HAD and pedicled adipose tissue, to prevent fistula development by providing wellvascularized coverage to further reinforce the BNC.