Experience with the artificial urinary sphincter model AS800 in 148 patients

The latest version of the artificial urinary sphincter, AS800, was used in 148 patients with urinary incontinence of different etiologies. Followup ranged from 3 to 37 months, with an average of 20.8 months. There were 112 (76 per cent) male and 36 (24 per cent) female patients. The cuff was implanted around the bladder neck in 78 patients (53 per cent) and around the bulbar urethra in 70 (47 per cent). Socially acceptable urinary control was achieved in 90 per cent of the 139 patients with active devices in place. It was necessary to remove the sphincter in 11 patients (7.4 per cent). The reasons for removal were infection and erosion in 8 patients (5.4 per cent), infection without erosion in 2 (1.3 per cent), and erosion due to excess pressure and poor tissues in 1 (0.7 per cent). Comparison of success and failure rates associated with incontinence of different etiologies revealed that patients with incontinence after failure of a conventional antistress incontinence operation and those with incontinence after transurethral resection or radical prostactectomy had the highest success rate, and that patients with incontinence secondary to pelvic fracture or exstrophy and epispadias had the highest failure rates. The deactivation feature (the lock) of the new artificial sphincter model was beneficial for primary deactivation, urethral catheterization or cystoscopy, or for elective nocturnal decompression of the bladder neck or urethral tissues.     

Treatment of the epispadias-exstrophy complex with the AS792 artificial urinary sphincter

The AS792 artificial urinary sphincter was implanted in 11 incontinent patients with the epispadias-exstrophy complex. To date 10 patients (91 per cent) are totally continent of urine with normal renal function and intact urinary systems. The recent reports concerning success with bladder neck reconstruction in this syndrome are reviewed. Owing to the relatively poor success of this procedure in achieving total urinary continence it is recommended strongly that insertion of the artificial urinary sphincter be the initial anti-incontinence procedure for these patients. The success rate with the artificial sphincter currently is superior to any form of bladder neck reconstruction in patients with the epispadias-exstrophy complex.     

Radical prostatectomy incontinence and the AS791 artificial urinary sphincter

The AS791 prosthetic sphincter was implanted in 66 patients with urinary incontinence after radical prostatectomy. Of these patients 49 (74 per cent) were continent 3 months to 4 1/2 years after implantation. Excluding the 22 patients who had had previous pelvic radiation therapy 41 (93 per cent) were continent. Mechanical problems have been few, establishing the reliability of this unique sphincter mechanism.     

Post-prostatectomy continence in the parkinsonian patient: the significance of poor voluntary sphincter control

A retrospective urodynamic study of 50 parkinsonian patients was done to determine the incidence and causes of post-prostatectomy incontinence. At presentation 22 per cent of the patients were incontinent. In 36 patients who underwent transurethral prostatectomy the incontinence rate was 17 per cent preoperatively and 28 per cent postoperatively. There was a clear association between normal voluntary sphincter control and urinary continence. After transurethral prostatectomy 5 of 6 patients continent preoperatively (83 per cent) who had abnormal sphincter control became incontinent compared to 1 of 24 (4.2 per cent) who had normal sphincter control. We conclude that the major risk of incontinence following prostatectomy in the parkinsonian patient is associated with lack of voluntary sphincter control.     

Success of the artificial urinary sphincter after failed surgery for incontinence

We implanted the artificial urinary sphincter in 15 incontinent patients for whom multiple urethral and bladder neck operations, including sphincter placement, had been unsuccessful. The 5 male and 10 female patients ranged from 3 to 26 years old (mean age 11 years). The etiology of incontinence was neurogenic bladder in 10 patients, epispadias in 2, exstrophy in 1, ectopic ureters in 1 and traumatic urethral disruption in 1. Of the 15 patients 13 required augmentation enterocystoplasty and clean intermittent catheterization. The initial anti-incontinence procedures were Young-Dees-Leadbetter bladder neck reconstruction in 10 patients, artificial urinary sphincter placement in 4 and bladder neck suspension in 1. Causes of failure of the primary treatment were erosion (artificial urinary sphincter), and incontinence and/or difficult catheterization (Young-Dees-Leadbetter). Followup from the last salvage operation averaged 21 months (range 6 to 37 months). A total of 58 operations was performed. Among the 4 patients in whom the artificial urinary sphincter eroded the bladder neck repeated attempts to place the cuff at the same site were unsuccessful and erosion occurred in all 4 within 1 year. Sphincter placement was more successful among the 11 patients who initially underwent Young-Dees-Leadbetter bladder neck reconstruction or bladder neck suspension; acceptable continence was attained in 8 patients (73%). We conclude that placement of the sphincter cuff around a previously eroded bladder neck probably will result in erosion. Sphincter implantation should be attempted in patients in whom bladder neck reconstruction has failed. Persistence in the treatment of these patients is essential because multiple operations often are necessary to achieve continence.     

Artificial urinary sphincters around intestinal segments--are they safe?

Artificial urinary sphincters (AUS) were implanted around intestinal segments to achieve urinary continence in 8 patients and faecal continence in 1. In 6 patients the cuff was placed around the lower end of the cystoplasty following bladder neck (5) or urethral (1) erosion. Four are completely dry, 1 on self-intermittent catheterisation (SIC). One has mild stress incontinence. In 1 patient the cuff eroded at 8 months. Two patients had cuffs implanted parastomally to create continent diversion. One is satisfactory on SIC and the other had her AUS explanted because of life-threatening metabolic acidosis. The rectal cuff was explanted because of faecal impaction above the cuff. As an absolute last resort, placing an AUS round a cystoplasty appears little more hazardous than round bladder neck. The use of the AUS for continent diversion has not been pursued because of reliable techniques of non-prosthetic continent diversion. The current model of the AUS is unsuitable for the treatment of faecal incontinence.     

The artificial urinary sphincter (AS 800): experience in 166 consecutive patients.

The artificial urinary sphincter model AS 800 was implanted in 166 patients with incontinence of various etiologies. Followup ranged from 6 to 94 months, with a mean of 41.6 months. Patient age ranged from 5 to 84 years, with a mean age of 59.4 years. There were 10 female patients (6%) and 156 male patients (94%). The cuff was implanted around the bladder neck in 27 patients (16%) and around the bulbous urethra in 139 (84%). A total of 40 reoperations (27 revisions and 13 device removals) was performed in 32 of 166 patients (19.3%). There were 13 mechanical device failures (7.8%), 11 cuff erosions (6.6%) and 2 periprosthetic infections (1.2%). Total or near total continence was achieved in 125 patients (75.3%), while 25 (15.1%) had improved urinary control.     

The significance of the open bladder neck associated with pelvic fracture urethral distraction defects.

PURPOSE: As a result of pelvic fracture urethral distraction defects, urinary continence relies predominantly on intact bladder neck function. Hence, when cystoscopy and/or cystography reveals an open bladder neck before urethroplasty, the probability of postoperative urinary incontinence may be significant. Unresolved issues are the necessity, the timing and the type of bladder neck repair. We report the outcome of various therapeutic options in patients with pelvic fracture urethral distraction defects and open bladder neck. We also attempt to identify prognostic factors of incontinence before urethroplasty. MATERIALS AND METHODS: We retrospectively reviewed the records of 15 patients with a mean age of 30 years in whom an open bladder neck was identified before posterior urethroplasty between January 1981 and October 1997. RESULTS: Of the 15 patients 6 were continent and 8 were incontinent postoperatively. One patient underwent artificial urethral sphincter implantation simultaneously with pelvic fracture urethral distraction defect repair and was dry postoperatively without sphincter activation. Average bladder neck and prostatic urethral opening on the cystourethrogram before urethroplasty was significantly longer in incontinent (1.68 cm.) than in continent (0.9 cm.) patients. Of the 8 patients who were incontinent 6 underwent bladder neck reconstruction, 1 artificial urinary sphincter and 1 periurethral collagen implant. Five patients with bladder neck reconstruction are totally continent and 1 requires 1 pad daily. The patient who underwent collagen implant requires 2 pads daily and the patient who received an artificial urethral sphincter has minor urge leakage. CONCLUSIONS: Open bladder neck before urethroplasty may herald postoperative incontinence which may be predicted by radiographic and cystoscopic features. Evaluation of the risk of postoperative incontinence may be valuable, and eventually guide the necessity and timing of anti-incontinence surgery, although our preference remains to manage the pelvic fracture urethral distraction defects and bladder neck problem sequentially. Bladder neck reconstruction provides good postoperative continence rates and is our technique of choice.     

The use of the AMS-AS800 artificial sphincter for continent urinary diversion. I. Investigations, including pressure-flow studies, using rabbit intestinal loops

The AS 800 genitourinary artificial sphincter was implanted in 40 New Zealand rabbits to evaluate its possible use for continent urinary diversion. This evaluation included the effects of varying closing pressures of the cuff implanted around isolated bowel loops. Six-weeks postoperative investigations included pressure/flow studies, autopsies, microangiographies and histologic evaluations. The sphincter was able to achieve continence during perfusion of the intestinal loop, maximum pressures being dependent on cuff pressures. Consistent changes were: 1) the formation of a thin fibrous capsule around the subcutaneously implanted pump, 2) the development of a fibrous sheath around the bowel beneath the cuff, and 3) fibrous and peritoneal reactions at the cuff site. In uncomplicated cases, the bowel wall tolerated the cuff pressure well, without macroscopic signs of atrophy. However, sphincter-related complications (1. infection, 2. erosion, 3. reduction of bowel circumference beneath the cuff) were pressure dependent and seen mainly in high pressure groups. Based on these results, the application of the sphincter for continent urinary diversion should include: low pressure urinary reservoirs, low pressure cuffs and most essentially, strict avoidance of infection.     

The impact of the artificial urinary sphincter in the neurogenic bladder on the upper urinary tracts

The charts and x-rays of 120 neurogenic bladder patients who underwent artificial sphincter implantation for treatment of urinary incontinence between 1973 and 1984 were reviewed retrospectively. Patients were followed for 3 to 130 months (average 36.8 months). The upper urinary tracts remained unchanged in 108 patients (90 per cent). Renal growth in children was undisturbed. Transient hydroureteronephrosis occurred in 8 patients (6.7 per cent) and progressive hydroureteronephrosis occurred in 4 (3.3 per cent). A total of 26 patients with vesicoureteral reflux (39 ureters) underwent ureteral reimplantation. Our results indicate that implantation of the artificial urinary sphincter in neurogenic bladder patients has minimal adverse impact on the upper urinary tracts, followup should be long-term and should include an IVP, outflow obstruction should be eliminated preoperatively by means of external sphincterotomy in male patients and bladder flap urethroplasty in female patients, similarly, adequate emptying of the bladder always must be assured during followup, if hydroureteronephrosis is detected early appropriate treatment can restore normal upper tracts, the presence of previously damaged upper tracts without evidence of obstruction is not a contraindication for artificial sphincter implantation and an antireflux operation in combination with artificial sphincter implantation is feasible.     

Pathophysiology of urinary incontinence after radical prostatectomy

To define the origin of urinary incontinence after radical prostatectomy urodynamic studies in 24 incontinent patients were compared to those of 13 continent patients. A statistically significant difference between incontinent and continent patients was found for the mean functional profile length (2.1 versus 3.6 cm., respectively, p less than 0.001), maximal urethral closure pressure (39 versus 74 cm. water, respectively, p less than 0.001) and maximal urethral closure pressure during voluntary contraction of the external sphincter (107 versus 172 cm. water, respectively, p less than 0.002). The differences among maximal detrusor pressure, initial bladder volume at which a detrusor contraction occurs, maximal cystometric capacity and residual urine were not statistically significant between the 2 groups. Urethral instability was present in 1 of the 24 incontinent patients (4.2%) and in none of the 13 continent patients, while detrusor instability was present in 6 (25%) and 3 (23.1%), respectively. Urethral and detrusor instability correlated poorly with incontinence (correlation coefficients 0.123 and 0.021, respectively). The appearance of the bladder outlet on voiding cystourethrography was correlated with urodynamic parameters and the presence or absence of continence. Tubularization above the level of the external sphincter was present in continent but absent in incontinent patients. Continence after radical prostatectomy is dependent upon sphincteric efficiency, which may be influenced by the anatomical configuration of the reconstructed bladder outlet and the integrity of the distal urethral sphincteric mechanism.     

Surgical treatment of the incontinent female patient with myelomeningocele

Surgical therapy was required for 42 incontinent female patients with myelomeningocele who had urodynamically documented high pressure bladders. Conservative treatment consisting of cholinolytic and alpha-adrenergic agents, and intermittent self-catheterization had failed. The surgical approach consisted of perivesical denervation (for hyperreflexia), Burch bladder neck suspension, enlargement cystoplasty and ureteral reimplantation when required. Among 33 patients (79 per cent) there was no incontinence on intermittent self-catheterization and 6 (14 per cent) had improvement with rare urgency or stress incontinence. In 3 patients (7 per cent) sphincteric incompetence required a transvaginal sling procedure.     

Post-prostatectomy incontinence: the influence of bladder dysfunction

The urodynamic studies of 38 patients referred for evaluation of incontinence after prostatectomy were reviewed. Only 15 patients (39.5 per cent) had pure sphincteric insufficiency as the sole cause of the incontinence. Of the 38 patients 16 (42 per cent) had sphincteric insufficiency combined with a significant component of bladder dysfunction (detrusor instability and/or low bladder wall compliance) as the cause of the incontinence. A total of 7 patients (18.5 per cent) had no evidence of sphincteric insufficiency but they had post-prostatectomy incontinence solely caused by detrusor instability and/or low bladder wall compliance. Of the patients referred for post-prostatectomy incontinence 60.5 per cent had bladder dysfunction as a major factor in the incontinence, which emphasizes the need for comprehensive urodynamic evaluation before treatment is recommended. Of 26 patients whose treatment was based on urodynamic findings and who were available for followup 23 (88 per cent) were adequately continent after treatment, with 35 per cent responding to pharmacological treatment alone and 54 per cent requiring placement of an artificial urinary sphincter with or without associated pharmacological therapy. The potential role of bladder dysfunction as a causative factor in post-prostatectomy incontinence must be considered to optimize the results of treatment and to avoid an unnecessary operation.     

Treatment of urinary incontinence with an artificial sphincter: further experience with the AS791/792 device

Artificial sphincter models AS791 and AS792 were used to treat 36 male and 7 female patients with urinary incontinence. Satisfactory results were obtained in 72 per cent of the patients. Of 100 surgical procedures performed to achieve these results 61 were planned procedures (initial implantation and delayed activation) and 39 were revisions required to improve continence, change mechanically failing devices or remove eroded sphincters. From our study 3 major problems with the artificial sphincter are apparent: 1) stress incontinence, which was present in 55 per cent of the patients with bulbous urethral sphincter compared to 21 per cent with sphincters located at the bladder neck, 2) erosions, which appear to be related to balloon pressure used and location of the artificial sphincter (there seems to be a higher incidence of erosions when the bulbous urethral site is used with balloon pressure greater than 80 cm. water) and 3) mechanical failures of the device, which accounted for 41 per cent of the unplanned operations in our series. These 3 major problems are reviewed, the possible etiology of persistent stress incontinence is discussed and possible ways to avoid these complications are suggested.     

The use of the artificial sphincter in the treatment of urinary incontinence in the female patient

Data analysis of my experience with the implantation of the artificial sphincter shows an overall success rate of 84 per cent. These results are in 139 females ranging from 5 to 84 years of age. The surgery is difficult primarily because the urethral-vaginal septum is not a surgical plane. Even partial injury to these tissues can lead to failure with erosion of the device into the urethra or vagina. The use of a new surgical instrument, the "cutter clamp" (see Fig. 8) is expected to improve results because of the precision it offers in dissecting around the bladder neck. Infection occurred in 4 of 139 patients, or 3 per cent. In one infected patient, the cuff eroded into the urethra. The infection rate may actually be higher because infection might account for some of the other erosions that occurred. Once erosion occurs, secondary infection can obscure the fact that the device was contaminated at the time of the original implantation. The use of a surgical isolation bubble system may lower both the incidence of infection and erosions in the future. The relief to the totally incontinent female by the artificial sphincter cannot be overestimated. The patients are very grateful, especially because most have undergone multiple treatment methods in an effort to cure their incontinence. The effectiveness of the device, barring infection or erosion, is evident by a success of 91 per cent of such patients being socially continent and 66 per cent being completely dry.     

Use of the AS792 artificial sphincter following urinary undiversion

Reconstruction of the urinary tract after diversion has been successful in patients with normal innervation of the lower tracts. However, the possibility of urinary incontinence after such major surgical procedures has dissuaded many surgeons from attempting urinary undiversion in patients in whom the continence status cannot be determined accurately before the operation or who were known to be incontinent before the original diversion. For this reason, the presence of neuropathic bladder dysfunction has been considered a relative contraindication to urinary undiversion unless it can be established preoperatively that the patient will obtain urinary continence. Eight patients are reported who had successful outcome with the use of the AS792 artificial urinary sphincter to control incontinence after urinary undiversion. Because of this successful experience it is now believed that patients with neuropathic bladder dysfunction or anatomically abnormal lower tracts are no longer precluded from urinary undiversion. A variety of methods has been used to reconstruct the urinary tract, including total reconstruction of the bladder and urethra with the sigmoid colon in 1 case. In the latter case the artificial sphincter was placed around the bowel segment to provide continence. The use of the artificial sphincter around a bowel segment offers many possibilities for reconstructive procedures involving bowel in the future.     

Incontinence, intermittent self-catheterization and the artificial genitourinary sphincter

Although the artificial genitourinary sphincter is ideally suited for incontinent patients who can empty the bladder completely, we have observed 22 patients with artificial sphincters who also perform intermittent self-catheterization to augment bladder emptying. No cuff erosions have occurred to date, with 11 patients on intermittent catheterization for more than 30 months. In patients who will require intermittent self-catheterization after sphincter implantation the cuff should be placed around the bladder neck. We believe that patients with sphincteric incontinence and decreased bladder contractility resulting in excessive residual urine volume are reasonable candidates for use of the artificial sphincter with intermittent self-catheterization.     

Salvage procedure for infected noneroded artificial urinary sphincters

PURPOSE: We report our experience with removal, antiseptic irrigation and immediate reimplantation of infected noneroded artificial urinary sphincters. MATERIALS AND METHODS: From April 1996 to October 2000, 8 patients with an infected artificial urinary sphincter underwent a total of 9 salvage operations. All patients underwent cystoscopy before salvage to ensure nonerosion of the sphincter cuff. All previously implanted material was removed, the wounds were copiously irrigated according to a 7 solution protocol and an identical new system was implanted. All patients were discharged home the following morning on oral antibiotics. RESULTS: Followup was 5 to 66 months (mean 33). The predominant organisms cultured at salvage were gram-positive cocci. Time from implantation to salvage was from 2 weeks to 64 months (mean 13.7 months). Prostatectomy was the etiology of incontinence in all except 1 case. In 5 of the 8 men a double cuff system was placed and 3 underwent concurrent 3-piece inflatable penile prosthesis salvage. The salvage procedure was done twice in 1 patient 5 months apart. The system was removed 16 months later secondary to urethral erosion. At the most recent followup the other 7 patients were free of infection with a functioning artificial urinary sphincter. CONCLUSIONS: Salvage and immediate reimplantation of an infected, noneroded single or double cuff artificial urinary sphincter appears to be a valid option. Our overall success rate was 87%. The usual offending organisms are gram-positive skin flora. An associated inflatable penile prosthesis does not prohibit simultaneous salvage of the 2 devices.     

Use of the artificial urinary sphincter in spinal cord injury patients

A total of 49 patients with neuropathic bladder dysfunction and urinary incontinence underwent implantation of the AS791/792 artificial urinary sphincter. Preoperative urodynamic evaluation allowed the bladder response to be categorized as hyperreflexia, areflexia and low compliance. The over-all success rate in obtaining total urinary continence in these patients was 70 per cent, although the type of bladder present did influence the degree of success. Although urodynamic evaluation is an essential prerequisite for sphincter implantation there were no clear-cut data that allowed an accurate prediction of the postoperative result. The only absolute contraindication to implantation of the artificial urinary sphincter is significant bladder fibrosis. Owing to the success in obtaining total urinary continence in this complicated group of patients, we believe that the artificial urinary sphincter should be considered in carefully selected patients with neuropathic bladder dysfunction secondary to spinal cord injury.     

The management of injuries to the urethra, bladder or vagina encountered during difficult placement of the artificial urinary sphincter in the female patient.

Between 1977 and 1989, an artificial urinary sphincter was implanted in 57 female patients. In 6 patients inadvertent intraoperative injuries to pelvic organs occurred, 5 of whom had a history of an average 2.8 previous operations for incontinence (range 2 to 4). The remaining patient was a 16-year-old girl with primary internal sphincter incompetence. All 6 patients presented with total incontinence. Intraoperative injury included 4 women who sustained vaginal perforations, while 1 had an anterior bladder perforation and in 1 the urethra was entered. Mechanisms of injury were sharp perforation of structures adherent to the pubis and blunt tears of distorted urethrovaginal tissues. Primary closures of the urethra, bladder and vaginal defects followed by insertion of the artificial urinary sphincter were accomplished successfully. Postoperative management included vaginal antiseptic packs, appropriate antibiotics and delayed sphincter activation. Of the 6 patients 5 remained dry after initial placement with a mean followup of 32 months (range 7 to 77). The remaining patient required replacement with a higher pressure balloon and a smaller cuff, which resulted in complete continence.