“Time isn’t the main thing. It’s the only thing.” – Miles Davis

As the adage goes, “timing is everything.” This attribute is particularly relevant when discussing evaluation and management of persistent or recurrent incontinence following artificial urinary sphincter (AUS) implant. Overall, the AUS is virtually unparalleled as an engineering marvel with astonishing durability presenting transformational gains for patients. Thus, if incontinence recurs, it is imperative to have a robust armamentarium to approach diagnosis and management. The following outlines key perspectives for evaluation, highlights aspects of our AUA/SUFU Guideline: Incontinence after Prostate Treatment¹ and contemporary high-yield resources,² and discusses treatment options to optimize patient outcomes.³ For the seasoned prosthetic surgeon, some of these insights may appear intuitive; however, the embedded nuances expand concepts for all implanters and ultimately serve to enhance treatments for our patients with stress urinary incontinence. As the most prevalent indication for AUS placement is incontinence after prostate treatment, most of the discussion will be focused on men with bulbar urethral cuff placement, although many of the concepts may be applicable to females and bladder neck placement.⁴

Early Recurrent Incontinence

Multiple scenarios exist that may provoke sub-optimal results in the weeks and months following AUS activation. In general, the following section addresses the first 6 months after device activation. Most implanters wait 4–6 weeks following AUS placement until activation.

Patient Selection and Related Factors

Prior to implantation of artificial urinary sphincter, clinicians should ensure that patients have adequate physical and cognitive abilities to operate the device (Clinical Principle)¹

Screening for the appropriate AUS candidate includes considerably more than assessment of stress leakage. Has the implanter excluded patients with chronic urinary infections, an irreversibly obstructed urinary tract, refractory storage symptoms, altered bladder compliance, or known allergies to AUS device components?⁵ One of the fundamental preoperative queries should pertain to possession of the cognitive and physical capabilities to appropriately manipulate the device.⁶ It is emboldened upon the surgeon to appropriately select patients who will be facile with AUS utilization. Was guidance provided regarding pump manipulation during healing to promote a dependent position within the scrotum and was the patient compliant with postoperative instructions? Is the patient able to adequately access the scrotal pump? Did the patient inadvertently deactivate the device? Does the patient note incontinence when standing from a sitting position on a hard surface, which may temporarily deform the cuff? Does the patient have urine trapping in foreskin? Does the patient allow adequate time after urination for cuff coaptation before walking away from the toilet? Did you set appropriate expectations for improvement with the patient preoperatively?

Keys to diagnosis: Interval history, physical examination to evaluate scrotal pump location and ability of clinician to cycle device with direct observation of patient technique can be illuminating.

Treatment strategies: Education of the patient regarding device utilization and outcome expectations is critical. In most instances, careful counseling will alleviate these early issues and allow for successful device use.

Early Mechanical Malfunction

Although exceptionally rare, both device and surgeon-related factors may contribute to mechanical faults in the months following device activation. Were there any complexities of placement in the operating room that may have contributed to damage to the components? Was the pressure regulating balloon (PRB) filled with the appropriate volume of fluid? Was there an immediate postoperative complication such as scrotal hematoma which may have impaired capacity to manipulate the pump? Is there suggestion of incomplete filling or air within the system during pump cycling? Was the cuff placed in a proximal bulbar location and appropriately sized?

Keys to diagnosis: Uncovering mechanical issues will be enhanced by knowledge of intraoperative and postoperative areas of concern, physical examination by the clinician to assess for cuff cycling with expected convexity of the full bulb, examination for capsule formation in the scrotum, perineal examination for cuff site abnormalities, as well as imaging to reveal fluid volume within the PRB which can be performed with contrast agents or saline filling. Cross-sectional imaging is preferred to allow accurate measurements of approximately 3.5 cm diameter (fig. 1).² Even if the pump appears to cycle appropriately, it has been postulated that less than 16 cc of fluid within a typical 61–70 cmH²⁰ PRB will not transmit appropriate forces for urethral coaptation.⁷ PRB herniation outside of the fascia will decrease ultimate pressure transmission to the urethra and the location should be assessed. Occasionally, exceptionally valuable insights will be revealed with imaging, such as inadvertent placement of the PRB in the peritoneal cavity (fig. 1). Of all the aspects of the AUS, very rarely is the scrotal pump the genesis of mechanical malfunction.

Figure 1. Cross sectional imaging to interrogate fluid volume and location of PRB. Note size of PRB to estimate volume. Also note intraperitoneal location of PRB noted in this patient prior to revision surgery.

Treatment strategies: Early mechanical malfunctions will often require operative revision and the enduring question: which component should be replaced? Attempts to spare components in the early time frame and manipulate only the parts necessary is optimal and several innovative strategies have been developed,⁸ although each revision surgery merits an individualized approach. If there is a substantial capsule surrounding the pump in the scrotum which precludes cycling, a scrotal incision and re-siting of the pump into a new dartos pouch will often be successful. Discovery that the cuff tab is not secured over the tubing adapter (button) may be encountered, albeit rarely. If there is not an obvious deficit noted at the PRB or cuff site, it is possible there has been damage to the connections or tubing and complete replacement of the device will be mandated. Additionally, downsizing or upsizing of the cuff may occasionally be indicated.

Contribution of Storage Symptoms

Pre-existing or de novo urgency urinary incontinence mandates thoughtful consideration and is of particular concern with patients following radiotherapy. High amplitude uninhibited detrusor contractions will generate pressures which can easily overcome the urethral pressures exerted at the level of the bulbar cuff. Other concerns would include screening for urinary retention with overflow incontinence, which may manifest even prior to device activation, and always be cognizant for possible urinary tract infection.

Keys to diagnosis: Pre-procedural history may provide substantial insight. Does the patient report incontinence associated with urgency or have leakage when supine? In select circumstances, functional evaluation with multichannel urodynamics will be of assistance in determining the primary etiology of the incontinence and ensure no bladder compliance changes exist which may place the upper tracts at risk. Although a relatively rare phenomenon, severe bladder dysfunction may be unmasked following AUS placement. Assessment of post-void residual and urinalysis will be important to gain insight.

Treatment strategies: For urgency incontinence, proceed along the pathway as outlined in Diagnosis and Treatment of Non-Neurogenic Overactive Bladder (OAB) in Adults: an AUA/SUFU Guideline.⁹

Early Cuff Erosion

Risks of early cuff erosion are primarily related to intraoperative and postoperative complications. Was there urethral injury during the dissection? Was there blood at the meatus following urethral dissection? Was there excessive bleeding during the urethral dissection suggestive of an unrecognized injury? Was there difficulty seating the cuff suggestive of an under-sizing error? Did the patient have preoperative urethral compromise including radiation, prior AUS, prior urethroplasty, prior or concurrent urological prosthetic, metabolic compromise, or a history of other potential urethral risk factors?² Did the patient require postoperative catheterization for urinary retention?

Keys to diagnosis: History of preoperative and intraoperative events will often increase index of suspicion for cuff erosion.

Treatment strategies: Erosion requires device explant as the system is irreversibly colonized even if not overtly infected. Most contemporary implanters will perform concurrent urethroplasty to potentially decrease urethral stricture formation (fig. 2). AUS reimplant may be considered in several months, typically at a new location or with an alternative approach such as transcorporal placement.¹⁰

Figure 2. A, urethral erosion secondary to AUS. Note presence of surrounding capsule following device explant. B, anastomotic urethroplasty at erosion site.

Late Recurrent Incontinence

Patients should be counseled that artificial urinary sphincter will likely lose effectiveness over time, and reoperations are common (Strong Recommendation; Evidence Level: Grade B)¹

Urethral Atrophy

Sub-cuff atrophy in the bulbar urethra represents a mismatch between the cuff size and urethral circumference resulting in decreased transmission of pressures. Chronic pressure on the corpus spongiosum from the AUS cuff may result in tissue compromise over years, although gradual fluid loss accompanied by the fixed mature capsule presents an equally valid hypothesis for diminished efficacy over time. Regardless of the mechanistic intricacies, increased periurethral space between the cuff backing and urethra decreases urethral coaptation at the cuff site. Typically, urethral atrophy is compensated for in the hydraulic system of the AUS by increased fluid volume within the cuff. For the experienced implanter, atrophy and elevated fluid capacity of the cuff can be recognized as a subtle finding of increased volumes transferred to the cuff during multiple pump compressions. The patient will often report a history of initial satisfactory results with a gradual recurrence of their incontinence over an extended period.

Keys to diagnosis: Urethroscopy is mandated in the evaluation of late incontinence to differentiate poor coaptation from cuff erosion. Cystoscopic technique requires a finesse essential to determine the etiology of the pathology. Most AUS implanters prefer to perform flexible cystoscopy for evaluation or for intervening on proximal pathology in the urethra or bladder. Prior to deactivating the device, the cystoscope is utilized to carefully evaluate the urethra from the fossa navicularis through the penile urethra and passed just distal to the cuff. A fully functional cuff will demonstrate symmetric coaptation without ability to visualize the proximal urethra. Incomplete coaptation is diagnostic of system malfunction (fig. 3). Once the activated cuff site is viewed, the cystoscope is removed and the AUS locked into the deactivated position. A brief waiting period of approximately 30 seconds is recommended just to ensure the cuff remains deactivated as noted by the continued concave dimple in the pump. The cystoscope is then traversed through the cuff site, which may display mild circumferential narrowing, but should not preclude passage of a flexible cystoscope. Pale mucosa may signal atrophy. The urothelium should not display bullae or pits suspicious for impending erosion. Of course, interrogation of this area for overt cuff erosion is essential. Evaluation for proximal stricture or bladder pathology may uncover necessity for additional interventions.

Figure 3. Urethroscopy for recurrent incontinence and AUS. A, cuff closed demonstrating open channel with lack of coaptation. B, cuff open to evaluate for erosion, proximal urethra, and bladder.

Treatment strategies: Although some experienced prosthetic surgeons advocate for capsule release, most cases will involve downsizing the cuff, replacing the cuff in a new location, or transcorporal placement. It benefits the patient for most remote mechanical malfunctions to replace all portions of the device. There is an occasional indication to drain and retain the implanted PRB during the revision surgery (fig. 1). Also available are PRBs which exert pressures higher than 61–70 cmH²⁰ although these are rarely utilized. There is limited enthusiasm for use of bulbar male slings, bulking agents, or investigational cell therapies for the AUS patient with recurrent incontinence.

Mechanical Deficiencies

Device malfunction over time is expected with prosthetic implants and all patients should be counseled that the need for revision due to mechanical issues would be the norm rather than the exception. Although unable to predict the longevity of the device for any given patient, overall expect revision rates of approximately 30% by 10 years post-implant.¹¹ Although some individuals will note a progressive increase in incontinence, mechanical dysfunction is often accompanied by an abrupt change in symptoms.

Keys to diagnosis: Interval history and physical examination to evaluate the ability of clinician to cycle the device will often reveal fluid loss. It is expected that wall tension in the PRB will decrease over time due to osmosis of the filling agent. Cystoscopy is prudent to rule out any concomitant urethral or bladder pathology as well as the potential for cuff erosion. In select circumstances, imaging may be utilitarian although less valuable if ultimately planning device revision.

Treatment strategies: Most instances of late mechanical malfunction require operative revision with device explant and potential future reimplant with all options as outlined above for urethral atrophy feasible.

Late Cuff Erosion

Classic teaching suggests that men with cuff erosion display hematuria, infection (characterized by dysuria) and recurrent incontinence. However, the presentation is frequently quite subtle with a consistent finding of late erosion being recurrent incontinence, which must be distinguished from urethral atrophy or mechanical compromise. Understanding the time course of the incontinence and external factors is critical. Was the patient catheterized with or without deactivation or for an extended period? Did the patient undergo other urological procedures such as rigid cystoscopy/ureteroscopy for stone disease? Did the patient undergo surveillance cystoscopy without AUS deactivation?

Keys to diagnosis: Interval history of risk factors for cuff erosion with urethroscopy mandated.

Treatment strategies: Device explant, urethroplasty and consideration for reimplant in several months. Insuring patients have medic alert tags or bracelets to identify the presence of the AUS if the patient is incapacitated can assist in preventing such device loss.

In conclusion, there are few procedures in urology that deliver the incredibly positive impact on a patient’s quality of life as AUS placement. Durable strategies for the prosthetic surgeon for evaluation and management of recurrent incontinence after AUS will ensure the device, and therefore patient outcomes, stand the ultimate test of time.

* National Principal Investigator for Boston Scientific: Artificial Urinary Sphincter Clinical Outcomes (NCT04088331).