Placement of an artificial urethral sphincter for treatment of passive urinary incontinence after inadvertent prostatectomy and balloon dilation treatment for stricture formation in a 5-month-old dog

OBJECTIVE

Describe the management of incontinence with several therapies, culminating with the apparently successful treatment utilizing artificial sphincter placement following an inadvertent prostatectomy.

ANIMAL

5-month-old 7.5-kg male neutered Miniature Schnauzer.

CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES

The patient was referred for dysuria and persistent stranguria following an iatrogenic total prostatectomy and urethrectomy. An extra pelvic urethral anastomosis was performed, followed by hospitalization for 2 weeks with a urinary catheter. The patient was further investigated for persistent stranguria, and a contrast urethrogram revealed a urethral stricture at the anastomosis site, which was treated with fluoroscopic balloon dilation. The stranguria resolved, but an acute nocturnal grade 3 passive urinary incontinence occurred, which was nonresponsive to medical management of phenylpropanolamine hydrochloride and estriol. An artificial urethral sphincter was placed, leading to continence after 5 top-ups to a total volume of 0.9 mL. The patient remained continent for 5.5 weeks before abrupt incontinence recurred, which was resolved by another 0.1-mL top-up. No further signs of incontinence occurred in the 11 months following.

TREATMENT AND OUTCOME

The placement of an artificial urethral sphincter successfully managed urinary incontinence in this patient. Continence was achieved with no significant complications other than a transient loss of continence. Long-term follow-up 14 months after sphincter placement revealed that the patient had remained continent since the final sphincter top-up. The owner reported a significant improvement in the patient's quality of life following successful incontinence management.

CLINICAL RELEVANCE

This case highlighted the benefits of placing an artificial urethral sphincter in managing urinary incontinence after select cases of prostatectomy in dogs that are unresponsive to medical management.

Development and future prospects of the artificial urinary sphincter

BACKGROUND

Urinary incontinence is a urinary disorder in which urine leaks out involuntarily. This disorder seriously affects the quality of life of patients. For patients with mild incontinence, conservative treatment and medication may be the ideal treatment modality, but for patients with severe incontinence, an artificial urinary sphincter is currently a better treatment option.

METHODS

In order to design an ideal artificial urinary sphincter, this article first searched and collected literature based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses searched strategy by selecting specific subject terms and reviewed the artificial urinary sphincters that are currently in the research stage based on different activation methods.

RESULTS

In response to the deficiencies of the existing artificial urinary sphincter, this article discusses the future optimization of the artificial urinary sphincter from three aspects: individual improvement of the artificial urinary sphincter, engineering design elements, and optimization of the artificial urinary sphincter manufacturing process.

CONCLUSIONS

The manufacture of an idealized artificial urinary sphincter capable of meeting clinical needs is of great importance to improve the quality of life of patients. However, this approach is a reasonable option to explore and should not be overestimated until further evidence is available.

Artificial sphincters: An overview from existing devices to novel technologies

Artificial sphincters (ASs) are used to replace the function of the biological sphincters in case of severe urinary and fecal incontinence (UI and FI), and gastroesophageal reflux disease (GERD). The design of ASs is established on different mechanisms, e.g., magnetic forces or hydraulic pressure, with the final goal to achieve a implantable and durable AS. In clinical practice, the implantation of in-commerce AS is considered a reasonable solution, despite the sub-optimal clinical outcomes. The failure of these surgeries is due to the malfunction of the devices (between 46 and 51%) or the side effects on the biological tissues (more than 38%), such as infection and atrophy. Concentrating on this latter characteristic, particular attention has been given to the interaction between the biological tissues and AS, pointing out the closing mechanism around the duct and the effect on the tissues. To analyze this aspect, an overview of existing commercial/ready-on-market ASs for GERD, UI, and FI, together with the clinical outcomes available from the in-commerce AS, is given. Moreover, this invited review discusses ongoing developments and future research pathways for creating novel ASs. The application of engineering principles and design concepts to medicine enhances the quality of healthcare and improves patient outcomes. In this context, computational methods represent an innovative solution in the design of ASs, proving data on the occlusive force and pressure necessary to guarantee occlusion and avoid tissue damage, considering the coupling between different device sizes and individual variability.

PDMS and DLC-coated unidirectional valves for artificial urinary sphincters: Opening performance after 126 days of immersion in urine

In this work, unidirectional valves made of bare polydimethylsiloxane (PDMS) and PDMS provided with a micrometric diamond‐like carbon (DLC) coating were fabricated and characterized, in terms of surface properties and opening pressure. The valve performance was also tested over 1250 repeated cycles of opening/closure in water, finding a slight decrease in the opening pressure after such cycles (10%) for the PDMS valves, while almost no variation for the PDMS + DLC ones. The valves were then immersed in urine for 126 days, evaluating the formation of encrustations and the trend of the opening pressure over time. Results showed that PDMS valves were featured by a thin layer of encrustations after 126 days, but the overall encrustation level was much smaller than the one shown by PDMS in static conditions. Furthermore, the opening pressure was almost not affected by such a thin layer of crystals. DLC‐coated valves showed even less encrustations at the same time‐point, with no significant loss of performance over time, although they were featured by a higher variability. These results suggest that most encrustations can be removed by the mechanical action of the valve during daily openings/closures. Such a self‐cleaning behavior with respect to a static condition opens exciting scenarios for the long‐term functionality of mobile devices operating in the urinary environment.

Artificial urinary sphincter: current status and future directions

Urge urinary incontinence (UUI) is one of the most troublesome complications of surgery of the prostate whether for malignancy or benign conditions. For many decades, there have been attempts to reduce the morbidity of this outcome with variable results. Since its development in the 1970s, the artificial urinary sphincter (AUS) has been the “gold standard” for treatment of the most severe cases of UUI. Other attempts including injectable bulking agents, previous sphincter designs, and slings have been developed, but largely abandoned because of poor long-term efficacy and significant complications. The AUS has had several sentinel redesigns since its first introduction to reduce erosion and infection and increase efficacy. None of these changes in the basic AUS design have occurred in the past three decades, and the AUS remains the same despite newer technology and materials that could improve its function and safety. Recently, newer compressive devices and slings to reposition the bladder neck for men with mild-to-moderate UUI have been developed with success in select patients. Similarly, the AUS has had applied antibiotic coating to all portions except the pressure-regulating balloon (PRB) to reduce infection risk. The basic AUS design, however, has not changed. With newer electronic technology, the concept of the electronic AUS or eAUS has been proposed and several possible iterations of this eAUS have been reported. While the eAUS is as yet not available, its development continues and a prototype device may be available soon. Possible design options are discussed in this review.

Comparative analysis of occlusion methods for artificial sphincters

An artificial sphincter is a device that replaces the function of the biological sphincter by occluding the relative biological lumen. The investigation of occlusion methods for artificial sphincters is crucial for a reliable and effective design of such devices. The compression induced onto the tissue by a certain pressure depends on the biomechanical and physiological features of the lumen and on the specific occlusion method. A numerical model and an experimental evaluation are presented here to assess the efficiency of different occlusion methods. Numerical models of circumferential occlusion and clamping occlusion methods to simulate the compression of the biological lumen were developed. Results revealed a relationship between the efficiency of the occlusion method and the physiological condition of the lumen. With differences related to the testing setup, this relationship was also confirmed experimentally by conducting tests on biological simulators. We analyzed the occlusion method to adopt as the physiological pressure (ie, leakage pressure values) changed. In particular, we focused on the urinary incontinence, which is a dysfunction involving the external sphincter surrounding the urethra. In this scenario, we demonstrated that a clamping occlusion is an efficient method to compress the urethra, whose physiological pressures range between 4 and 12 kPa. The clamping occlusion method resulted up to 35% more efficient in terms of sealing pressure than the circumferential one for a closing pressure varying between 2.3 and 11.5 kPa.

Surgical treatment of post-prostatectomy stress urinary incontinence in adult men: Report from the 6th International Consultation on Incontinence

AIMS

To report the recommendations of the 6th International Consultation on Incontinence (ICI) on post-prostatectomy urinary incontinence.

METHODS

The 6th ICI committee on surgical treatment of urinary incontinence in men assessed and reviewed the outcomes of surgical therapy and updated the prior recommendations published in 2013. Articles from peer-reviewed journals, abstracts from scientific meetings, and literature searches by hand and electronically formed the basis of this review. The resulting guidelines were presented at the 2016 ICI meeting in Tokyo, Japan.

RESULTS

Voiding diary and pad tests are valuable for assessing quantity of leakage. Cystoscopy and/or urodynamics may be useful in guiding therapy depending on the type of incontinence and presumed etiology. Artificial Urinary Sphincter (AUS) is the preferred treatment for men with moderate to severe stress urinary incontinence (SUI) after RP. Male slings are an acceptable approach for men with mild to moderate SUI. Much discussion centers on the definition of moderate SUI. Injectable agents have a poor success rate in men with SUI. Options for recurrent SUI due to urethral atrophy after AUS implantation include changing the pressure balloon, downsizing the cuff and increasing the amount of fluid in the system. Infection and/or erosion demand surgical removal or revision of all or part of the prosthesis.

CONCLUSIONS

Although there are several series reporting the outcomes of different surgical interventions for PPUI, there is still a need for prospective randomized clinical trials. Recommendations for future research include standardized workup and outcome measures, and complete reporting of adverse events at long-term.

[Not Available]

Zusammenfassung. Dieser Übersichtsartikel beleuchtet den aktuellen Kenntnisstand zur Ätiologie, Diagnostik und Therapie der Harninkontinenz des Mannes. In der Ätiologie der Harninkontinenz beim Mann spielt die radikale Prostatektomie eine herausragende Rolle, aber auch das benigne Prostatasyndrom, neurologische Erkrankungen oder metabolische Störungen können zu einer Harninkontinenz beim Mann führen. In der Diagnostik ist neben der Basisdiagnostik eine qualifizierte urodynamische Beurteilung unabdingbar, um die zugrunde liegenden pathophysiologischen Mechanismen aufzudecken und Chancen und Risiken der verfügbaren Therapie- bzw. Operationstechniken abschätzen zu können. Die Primärtherapie der Harninkontinenz beim Mann ist konservativ und schliesst eine qualifizierte Beckenboden- und Sphinktertherapie einschliesslich Biofeedback ein. Die Auswahl der operativen Techniken unterliegt dem Ausmass der Inkontinenz, den individuellen Gegebenheiten des Patienten, der Patientenpräferenz, der Expertise des Operateurs und einzelnen Kontraindikationen für bestimmte Verfahren. Auch ein längeres Intervall nach radikaler Prostatektomie oder ein Tumorprogress sind keine Ausschlusskriterien für eine operative Therapie. Der oft hohe Leidensdruck und das breite Spektrum von in geübten Händen wenig invasiven Operationstechniken rechtfertigen eine breite Indikationsstellung für eine prothetische Versorgung.

[Stepwise correction of urethrovesical anastomotic stenosis and severe incontinence (a clinical case report)]

The article presents a clinical case report of a stepwise correction of urethrovesical anastomotic stenosis and severe incontinence. At the first stage the authors performed re-urethrovesical anastomosis making the patient totally incontinent. At the second stage, an artificial sphincter was implanted.

Reconstructive surgery for male stress urinary incontinence: Experiences using the ATOMS(®) system at a single center

OBJECTIVE

To propose possible success-driven solutions for problem and complication rates encountered with the ATOMS(®) sling system, based on first-hand experience; and to provide possible actual alternative scenarios for the treatment of male stress urinary incontinence (SUI).

PATIENTS AND METHODS

During the defined period (between 4/2010 and 04/2014), 36 patients received ATOMS(®) system implants at our clinic. We collected pre- and post-operative evaluation data using the International Consultation on Incontinence Questionnaire Short Form (ICIQ SF). As an expansion of the questionnaire, we added questions about post-operative perineal pain, the general satisfaction with the results of the intervention and willingness to recommend the operation to a best friend.

RESULTS

Our data shows a relatively high explantation rate, but a surprisingly high patient satisfaction rate. Explantation was required mainly due to late onset infections or other symptomatic factors. Compared to other studies early onset infections were rare.

CONCLUSION

A non-invasive, uncomplicated adjustable system to alleviate male stress urinary incontinence remains a challenge. Although there are various systems available for the treatment of male stress urinary incontinence, it seems that despite the advantages of the ATOMS(®) system, an artificial sphincter system may pose more advantages based on our experience, understanding and knowledge of its well-documented long-term solutions and problems.