Bladder Neck Closure in Association with Continent Urinary Diversion

0022-5347/95/i542-0aa3$03.00/0 ”HE JUWAL OF UROLUCY Copyright 0 1995 by AMERICAN UROLOCICAL ASSOCIATION, INC.

BLADDER NECK CLOSURE IN ASSOCIATION WITH CONTINENT URINARY DIVERSION TERRY W. HENSLE, ANDREW J. KIRSCH, WILLIAM A. KENNEDY, I1 AND ELIZABETH A. REILEY From the Babies and Children’s Hospital of New York, Columbia-Presbyterian Medical Center, New York, New York

ABSTRACT

Bladder neck closure is not a standard part of continent urinary diversion. When bladder augmentation and continent urinary diversion are done simultaneously, it is frequently convenient and advantageous to leave the native bladder neck intact as long as there is a reasonable degree of intrinsic continence. Even in patients with marginal control the effect of lowering intravesical pressure and increasing intravesical volume will often produce acceptable continence. At times, particularly in patients who have undergone multiple surgical procedures involving the bladder neck, there is poor intrinsic resistance. To provide acceptable continence in these cases bladder neck closure is a necessary part of continent diversion. Between 1990 and 1993 we treated 6 male and 7 female patients, most of whom underwent simultaneous bladder augmentation and continent urinary diversion, and they had poor intrinsic outlet resistance. Patient age ranged from 8 to 22 years. Underlying diagnoses included thoracic myelomeningocele in 5 patients, bladder exstrophy in 5, bladder leiomyosarcoma in 1 and extensive pelvic trauma in 1 as well as 1 previously separated conjoined twin. Three patients had artificial urinary sphincter failure and 3 had failure of urethral sling procedures. A clean intermittent catheterization program had failed in 12 patients and all 13 had diurnal incontinence. Bladder neck and urethral resistance was evaluated using voiding cystourethrography and urodynamics to measure leak point pressure and bladder capacity. Reliable bladder neck closure is historically difficult to achieve and is best done at the time of diversion. We have had initial success in 12 of our 13 cases and subsequently in all 13 using a technique of bladder neck division, 2-layer closure and omental interpositionbetween the bladder neck closure and urethra. KEYWORDS: bladder, urinary diversion, d y n a m i c s

Bladder neck closure is not necessarily an integral part of continent urinary diversion. When bladder augmentation and continent urinary diversion are done simultaneously, it is frequently convenient and advantageous to leave the native bladder neck intact as long as there is a reasonable degree of intrinsic sphincteric competence. Even in patients with marginal sphincteric control the effect of lowering intravesical pressure and increasing intravesical capacity will usually produce acceptable urinary continence. However, particularly in patients with severe neurological lesions or those who have undergone multiple surgical procedures at the bladder neck, there is poor intrinsic resistance. To provide acceptable continence bladder neck closure becomes a necessary part of continent urinary diversion. METHODS AND MATERIALS

During a 3-year period between 1990 and 1993,6male and 7 female patients presented to our institution for formal bladder neck closure in association with continent urinary diversion. Patient age ranged from 8 to 22 years (average 16.3).Underlying diagnoses included thoracic myelomeningocele in 5 patients, bladder exstrophy in 5, rhabdomyosarcoma in 1 and massive pelvic trauma in 1as well as 1 patient who had been a conjoined twin. Bladder neck closure was done as a primary procedure in 5 patients and as a secondary procedure in 8. Of the 13 patients 11 had previously undergone surgery, including bladder neck procedures for continence in 5, bladder augmentation and simultaneous placement of an artificial urinary sphincter in 3 and bladder augmentation with use of a bladder neck fascial sling in 3. “WOpatients had undergone previous placement of an artificial urinary sphincter alone, 1 had undergone transpubic methroplasty and 1 had had previous external radiation

treatment to the area of the bladder neck. Many of these children, particularly those with exstrophy, had undergone multiple surgical procedures before definitive continent diversion and bladder neck closure. Ofthe 13 patients a program of bladder paralyzation and clean intermittent catheterization had failed in 12. All patients had diurnal incontinence. The patient who was not on intermittent catheterization had extensive pelvic trauma and urethral disrup tion, and intermittent catheterization was a technical impossibility. Bladder augmentation in association with continent urinary diversion was done in 12 of the 13 patients. Bowel segments used included cecum in 9 patients, stomach in 2 and ileum in 1. The mechanism of continence was the Mitrofanoff principle in 8 patients, a catheterizable appendiceal stoma in 7 and tapered ileal segment in 1.In the other 5 patients the ileocecal valve was used as a continence mechanism with a catheterizable tapered ileal stoma. All patients in this series who were considered candidates for continent urinary diversion had video urodynamics performed before the procedure. Bladder capacity and leak point pressure were measured, and the results are listed in the table. It is of interest that 3 patients had a leak point pressure of greater than 30 cm. water before augmentation and continent urinary diversion yet they had urethral incontinence followingthe procedure. The figure shows a case in this category with a preoperative bladder capacity of 80 cc and a leak point pressure of greater than 30 cm. water. This postoperative cystogram demonstrates a 400 cc capacity reservoir with obvious urethral leakage. Only 1patient had a reasonable preoperative bladder capacity and did not require augmentation at the time of bladder neck closure and continent diversion. Complete, reliable bladder neck closure involves division of

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BLADDER NECK CLOSURE AND CONTINENT URINARY DIVERSION hpenatiw umdynamicevalwtion

No.pts.

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6o-90 Greatar than 200 Leak point pre%sure (am water): Lessthan6 6-10 1&20

Orsaterthan30

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degree of renal failure. It ie likely that excess urine pmduction overwhelms the capacity of the reservoir at 3 hours. One patient had disruption of the bladder neck closure. The child with extensive pelvic trauma underwent initial bladder neck closure without the interposition of a vascularized layer and recanalization of the urethra occurred aRer 1 month. At the time of secondary closure a portion of tunica vaginalis was placed between the 2 urethral ends and that closure has remained intact. DISCUSSION

Continent urinary diversion in childhood has become a widely accepted alternative for children in whom there is an inadequate urinary reservoir and/or an unreliable continence mechanism.l-9 The principles of continent urinary diversion in children and adults are to create a large capacity, low pressure reservoir, obtain a reliable continence mechanism and provide an easily catheterizable stoma. In the pediatric age p u p most patients are born with bladder exstrophy or severe neurological impairments, such as myelomeningocele.1-9 In this particular group it is convenient to use the native bladder as part of the continent diversion.'-6 Particularly when the uretemvesical junction is competent, the native bladder serves as a reliable base on which to place an augmentation. In addition, if the Mitiofanoff principle is used for continent diversion, the native bladder is clearly the best site for suburethral implantation of the appendix. Most patients who require continent urinary diversion present initially with urinary incontinence secondary to the high pressure, low capacity reservoir andor sphincteric incompetence. Many children require a continence procedure at the bladder neck in conjunction with continent diversion. However, it is often difticult to identify reliably preoperatively which of these individuals will require formal bladder neck closure. As originally described, the Mitrofanoff principle of continent diversion included formal division of the urethra below the bladder neck with separate closure of the urethra at both ends.7 In the last decade it has become clear that in many instances simply creating a large capacity, low pressure reservoir w i l l result in urinary continence, particularly in those with a moderate degree of sphincteric competence. Critical assessment of bladder neck competence is essential to define better which patients will require formal bladder neck closure. That critical assessment usually involves a preoperative determination of bladder capacity and Poetoperative cyetogram of thoracic myelomeningocele patient leak point pressure. In our series it was clear from the urowith bladder capacity of400 cc and obvioua urethral leakage (arrow). dynamic data that 10 of the 13 patients would require a bladder neck procedure at the time of continent urinary diversion. All 10 patients had leak point pressures of less the bladder neck. If bladder neck closure is being done in than 20 cm. water and bladder capacity of less than 90 cc. conjunction with augmentation, the procedure is best done Several of these patients had undergone previous procedures with the bladder open and under direct vision. Closure of in an attempt to attain urinary continence, including multiboth ends of the urethra in 2 layers with long lasting mono- ple bladder neck reconstructions in the exatrophy patients, filament absorbable material is preferable. This interposition placement of an artificial urinary sphincter in several and of a vascularized layer between the 2 ends of urethra pro- the use of a fascial bladder neck sliig in others. However, 3 videe the best results.Ifbladder neck closure is being done in of our patients were found on initial evaluation to have a conjunction with augmentation, then omentum provides the bladder capacity of less than 90 cc with a leak point pressure best ~ourceof this interposed layer. In secondary cases or of greater than 30 cm.water. In these instancesthe bladder when the peritoneum is not entered the tunica vaginalis in neck was not closed at the time of continent urinary diversion the male or a labial fat pad in the female patient can be easily and all patients have subsequently required secondary formobilized and used for the interpositional layer. Postopera- mal bladder neck closure because of persistent urethral intively the area of closure is routinely drained with a standard continence.These patients are confined to bed and chair with thoracic myelomeningocele. The abdominal pressure and sump drain. straining during transfer from bed to chair are the most likely c a w s of incontinence although this has not been RESULTS formally evaluated. Of our 13 patients 11 are dry for greater than 4 hours Of our 13 patients 8 required secondary bladder neck dobetween catheterizations. Two patients have some stomal sure, including 5 in whom other procedures were not adeleakage after 3 hours, both of whom have impaired concen- quate to provide urethral continence and 3 in whom initial trating ability and are polyuric secondary to a moderate evaluation was misleading. Bladder neck closure in conjunc-

BLADDER NECK CLOSURE AND CONTINENT URINARY DIVERSION tion with continent urinary diversion is not a new concept and others have advocated its use.6.8.9 We believe that bladder neck closure should be considered as a primary procedure in many of these difficult cases as a superior alternative to artificial urinary sphincter or bladder neck sling procedures. In addition, we think that the preoperative assessment of bladder neck competence, particularly in the high myelomeingocele patient, may be misleading. Formal bladder neck closure can be a difficult surgical procedure and there are numerous reports of failure of bladder neck closure with recanalization of the urethra.10.11 Our surgical technique has proved to be reliable in 12 of our 13 ases. The single failure and recanalization occurred in the m e of massive pelvic trauma in which bladder neck closure did not include the interposition of a vascularized tissue layer between the 2 ends of the urethra. Secondary closure involved the placement of a tunica vaginalis flap over the divided, resutured urethral ends. “he patient has remained dry since the secondary procedure. The importance of completely dividing the bladder neck, closing both ends of the urethra in 2 layers and, most importantly, interposing a vascularized tissue flap cannot be emphasized too greatly. We do not believe that formal bladder neck closure is necessary in every patient undergoing continent urinary diversion when the native bladder is used as part of the reservoir. However, based on our experience we think that bladder neck closure should be considered in certain patients, particularly those with preoperatively demonstrable sphincteric incompetence. Bladder neck closure is clearly a better alternative than the artificial urinary sphincter or ureteral sling procedures in this difficult group. In addition, patients with neurological impairment, such as high myelomeningocele, should be considered candidates for bladder neck closure although preoperative urodynamic evaluation might demonstrate an acceptably high leak point pressure. We also believe

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that the technical approach to bladder neck closure must be done in a meticulous fashion to ensure success. Total division of the bladder neck with a 2-layer closure and interposition of a vascularized tissue layer is the only way to ensure success. REFERENCES

1. Hensle, T. W., Connor, J. P. and Burbige, K. A: Continent urinary diversion in childhood. J. Urol., 143: 981,1990. 2. Boni, P.A, Bruce, J. and Gough, D. C. S.: Continent cutaneous diversions in children: experience with the Mitrofanoff procedure. Brit. J. Urol., 7 0 669,1992. 3. Riedmiller, H., Thuroff, J., Stockle, M., Schofer, 0. and Hohenfellner, R.: Continent urinary diversion and bladder augmentation in children: the Mainz pouch procedure. Ped. Nephrol., 3 68,1989. 4. Gearhart,J. P.and Jeffs, R.D.: Augmentation cystoplaety in the failed exstrophy reconstruction. J. Urol., 139 790, 1988. 5. Elder, J. S.:Continent appendicoeolostomy: a variation of the Mitrofanoff principle in pediatric urinary tract reconetruetion. J. Urol., 148: 117,1992. 6. Woodhouse, C. R. J. and Gordon, E. M.: The Mitrofanoffprinciple for urethral failure. Brit. J. Urol., 73: 55, 1994. 7. Mitrofanoff, P.: Cystostomie continente trans-appendiculaire dam le traitement des vessiea neurologiques. Chir. Ped.,21: 297,1980. 8. Dykes, E. H.,Duffy, P. G. and Ranaley, P. G.: The use of the Mitmfanoff principle in achieving clean intermittent eatheterbation and urinarv continence in children. J. Ped.Sure.. 28.535.1991. 9. Wan. J. L. and McGuire. E. J.: Amentation cmto~lastyand cl&ure of the urethra for the desGyed lower &&y &ct. J. h e r . Paraplegia Soe., 1 3 40,1990. 10. Weingarten, J. L. and Cromie, W. J.: The Mitrofanoff principle: an alternative form of continent urinary diversion. J. Uml., 140: 1529,1988. 11. Monfort, G.,Guys, J. M. and Moriseon Lacombe, G.: Appendicovesicostomy: an alternative urinary divemion in the child. Eur. Urol., 10: 361,1984.

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