Pubovaginal sling using cadaveric allograft fascia for the treatment of intrinsic sphincter deficiency

Managing female pelvic floor disorders: a medical device review and appraisal

Pelvic floor disorders (PFDs) will affect most women during their lifetime. Sequelae such as pelvic organ prolapse, stress urinary incontinence, chronic pain and dyspareunia significantly impact overall quality of life. Interventions to manage or eliminate symptoms from PFDs aim to restore support of the pelvic floor. Pessaries have been used to mechanically counteract PFDs for thousands of years, but do not offer a cure. By contrast, surgically implanted grafts or mesh offer patients a more permanent resolution but have been in wide use within the pelvis for less than 30 years. In this perspective review, we provide an overview of the main theories underpinning PFD pathogenesis and the animal models used to investigate it. We highlight the clinical outcomes of mesh and grafts before exploring studies performed to elucidate tissue level effects and bioengineering considerations. Considering recent turmoil surrounding transvaginal mesh, the role of pessaries, an impermanent method, is examined as a means to address patients with PFDs.

Pubovaginal sling materials and their outcomes

Stress urinary incontinence (SUI) is the most common type of urinary incontinence, and approximately 200 different methods have been described for its surgical management. A better understanding of the pathophysiology of SUI has led to the development of surgical therapies focused on creating a strong suburethral supportive layer and urethral resistance. The most important advantage of the pubovaginal sling (PVS) procedure is that it restores urethral resistance during stress maneuvers to prevent incontinence, while improving urethral coaptation at rest and allowing for spontaneous micturition. Various autologous, allograft, xenograft and synthetic materials have been used for the PVS. The autologous PVS procedure for the treatment of SUI offers the highest success rate and is the most commonly used PVS surgical method. Unlike xenograft and allograft materials, the autologous procedure does not result in a tissue reaction and is associated with a low rate of material-related complications.

Complications of grafts used in female pelvic floor reconstruction: Mesh erosion and extrusion

Introduction:

Various grafts have been used in the treatment of urinary incontinence and pelvic prolapse. Autologous materials such as muscle and fascia were first utilized to provide additional anatomic support to the periurethral and pelvic tissues; however, attempts to minimize the invasiveness of the procedures have led to the use of synthetic materials. Complications such as infection and erosion or extrusion associated with these materials may be troublesome to manage. We review the literature and describe a brief overview of grafts used in pelvic floor reconstruction and focus on the management complications specifically related to synthetic materials.

Materials and Methods:

We performed a comprehensive review of the literature on grafts used in pelvic floor surgery using MEDLINE and resources cited in those peer-reviewed manuscripts. The results are presented.

Results:

Biologic materials provide adequate cure rates but have associated downfalls including potential complications from harvesting, variable tissue quality and cost. The use of synthetic materials as an alternative graft in pelvic floor repairs has become a popular option. Of all synthetic materials, the type I macroporous polypropylene meshes have demonstrated superiority in terms of efficacy and fewer complication rates due to their structure and composition. Erosion and extrusion of mesh are common and troublesome complications that may be managed conservatively with observation with or without local hormone therapy, with transvaginal debridement or with surgical exploration and total mesh excision, dependent upon the location of the mesh and the mesh type utilized.

Conclusions:

The ideal graft would provide structural integrity and durability with minimal adverse reaction by the host tissue. Biologic materials in general tend to have fewer associated complications, however, the risks of harvesting, variable integrity of allografts, availability and high cost has led to the development and use of synthetic grafts. Synthetic grafts have a tendency to cause higher rates of erosion and extrusion; however, these complications can be managed successfully.

How to achieve long-term success in the treatment of female urinary stress incontinence? Novel modification on vaginal sling

Purpose

Modest long-term success is one of the most disappointing issues facing patients undergoing anti-incontinence surgery. Herein we introduce a novel surgical modification of the vaginal sling to address the mechanisms that may lead to a reduction in the success rate at the long-term follow-up.

Materials and Methods

Twenty-three female patients with mean age of 48.2 years (range, 22-73 years) underwent anti-incontinence surgery to correct their stress urinary incontinence (SUI) between August 2006 and January 2008. The in situ anterior vaginal wall sling, reinforced with equi-size monofilament polypropylene tape, was used as an anti-incontinence surgical procedure. The mean follow-up period was 30.2 months (range, 24-38 months).

Results

The surgical technique was successful in 22 patients (95.65%); 20 of them were cured and 2 patients showed clinical improvements. Urinary retention was observed in one patient (4.34%), which was resolved after decreasing the tension of the suspension sutures. No significant post-voiding residue was detected postoperatively.

Conclusions

Cost-effectiveness and a low risk of urethral erosion, due to the presence of intervening vaginal mucosa, are important advantages of this technique. Long-term success is expected, because relaxation of the non-tension-free suspension sutures and dislocation of the midurethral sling are less likely.

Comparison of solvent-dehydrated allograft dermis and autograft rectus fascia for pubovaginal sling: questionnaire-based analysis

OBJECTIVES

To evaluate the efficacy of pubovaginal sling using human cadaveric dermis processed by solvent dehydration and compare results to those of another group in which autograft rectus fascia was used.

MATERIAL AND METHODS

The efficacy of autologous rectus fascia (group 1, n=25) or solvent-dehydrated cadaveric dermis (group 2, n=24) for pubovaginal sling were compared in women with stress urinary incontinence (SUI). Surgical outcome, patient satisfaction and quality of life was assessed by the urogenital distress inventory (UDI-6) and the incontinence impact questionnaire (IIQ-7).

RESULTS

Mean follow-up for patients in group 1 and group 2 were 18 and 13 months, respectively. Our questionnaire-based assessment revealed that SUI was either cured or improved in a total of 21 (84%) patients in group 1 and 19 (79%) patients in group 2. No statistically significant difference was found for the overall success (P<0.05) and no major complications were encountered in both groups.

CONCLUSIONS

Use of allograft dermis as an alternative to autologous rectus fascia for pubovaginal sling had comparable improvement in patient satisfaction and quality of life at intermediate term.

Solvent-dehydrated cadaveric dermis: a new allograft for pubovaginal sling surgery

AIM

The aim of this study was to evaluate the efficacy of solvent-dehydrated cadaveric dermis in pubovaginal sling surgery for the first time in the literature.

METHODS

Twenty-five women with stress urinary incontinence underwent pubovaginal sling surgery using 2 x 12 cm allograft dermis. Preoperatively, all patients were evaluated by a detailed urogynecologic evaluation, voiding diary, pelvic examination and urodynamic investigation. Outcome was assessed by the Urogenital Distress Inventory short form and standardized follow-up questionnaires.

RESULTS

Twenty (80%) patients were cured of stress incontinence symptoms. Seventeen wore no pad and three reported occasional stress urinary incontinence and used no or one pad at a mean follow up of 12 months. Five (20%) patients in our series experienced the same amount of leakage as before the surgery. Seventy-six percent of the patients indicated that urinary incontinence was no longer negatively affecting their daily life and were satisfied with the procedure.

CONCLUSIONS

Questionnaire-based assessment of outcome suggests that solvent-dehydrated cadaveric dermis is effective in the treatment of stress urinary incontinence. However, larger and comparative prospective studies with long-term results and randomized comparison of tissue preparation techniques are warranted.

A tissue-engineered suburethral sling in an animal model of stress urinary incontinence

OBJECTIVE

To create and evaluate the functional effects of a tissue-engineered sling in an animal model of stress urinary incontinence (SUI).

MATERIALS AND METHODS

Twenty female Sprague-Dawley rats were divided into four equal groups: a control group (C) had no intervention before the leak-point pressure (LPP) was measured; a denervated group (D) had bilateral proximal sciatic nerve transection (PSNT) and periurethral dissection with no sling placed; group S had concomitant bilateral PSNT and a suburethral sling of small intestinal submucosa (SIS) placed; and group (M) had concomitant bilateral PSNT with implantation of a tissue-engineered sling. The suburethral sling was placed via a transabdominal approach with the sling sutured to the pubic bone. Tissue-engineered slings were prepared with muscle-derived cells obtained via the pre-plate technique and subsequently seeded for 2 weeks on a SIS scaffold. Suburethral slings were implanted 2 weeks before LPP testing, using the vertical-tilt method.

RESULTS

Surgically placing a suburethral sling is feasible in the female rat, with few complications. LPPs from both sling groups (S and M) were not significantly different from untreated controls (C). The S, M and C groups all had significantly higher LPPs than group D. Importantly, no rat from either sling group (S and M) had signs of urinary retention.

CONCLUSIONS

Placing tissue-engineered slings in an animal model of SUI resulted in LPP values that were not significantly different from those in untreated control or SIS (S) groups. These data show that incorporating muscle stem cells into SIS slings does not adversely alter the advantageous mechanical properties of the SIS sling in a model of SUI, and provide the basis for future functional studies of tissue-engineered sling materials with long-term retention.

Synthetic sling options for stress urinary incontinence

In the past decade, sling surgery has become the preferred technique for the management of female stress urinary incontinence. A greater understanding of the pathogenesis of stress urinary incontinence and a greater durability and effectiveness for sling surgery has allowed this technique to become the benchmark for treatment of female stress urinary incontinence. As a consequence, a multitude of products have been developed using various techniques and materials to perform sling surgery. This article reviews the materials and techniques available and the complications associated with each. Most importantly, the outcomes are discussed so that the readers can best understand the impact of these surgeries on our patients.

Surgical outcome of abdominal sacrocolpopexy with synthetic mesh versus abdominal sacrocolpopexy with cadaveric fascia lata

Nineteen women who had an abdominal sacrocolpopexy (ASC) with synthetic mesh and 18 women who had an ASC with freeze-dried, irradiated cadaveric fascia lata returned for blinded pelvic organ prolapse quantification (POPQ) examinations. The mean relative vaginal descent (delta) from perfect total vaginal length in the mesh group was 1.1 (0.3) cm, and the delta in the fascia group was 2.8 (0.8) cm (p=0.02, Mann-Whitney U). The proportion of women with "optimal" surgical outcome in the mesh group was 89% and 61% in the fascia group (p=0.06, Fischer's exact test). This study suggests that cadaveric fascia lata may not be a good choice for ASC.

Sling procedures for urinary incontinence in women

There are many different techniques of sling surgery for female incontinence and numerous materials are available for use as a suburethral sling. Autologous materials are associated with more success and fewer complications than cadaveric material. The objectives of this review are to identity the benefits and adverse effects of suburethral sling procedures. There is no evidence that suburethral slings are better or worse than other surgical or conservative management because no trials have addressed this comparison.

The tensile properties of tension-free vaginal tape and cadaveric fascia lata in an in vivo rat model

OBJECTIVE

To examine the tensile properties (break load and maximum average load), after in vivo implantation in a rat animal model, of tension-free vaginal tape (TVT) and cadaveric fascia lata (CFL), as pubovaginal slings of these materials have become popular for treating stress urinary incontinence.

MATERIALS AND METHODS

Twenty Sprague-Dawley rats (300-400 g) had 1 x 2 cm strips of commercially available TVT and CFL implanted on the right and left anterior abdominal wall, respectively. Half of the animals were then killed at 6 weeks and the remainder at 12 weeks, after which the strips of TVT and CFL were removed and their tensile properties measured using a tensiometer. The tensile strength of TVT and CFL strips maintained only in normal saline served as controls.

RESULTS

The TVT strips had a mean break load of 0.740 kg in the control and only 0.390 kg for CFL (P < 0.05). At 6 weeks the TVT material had a mean (sd) maximum average load of 0.634 (0.096) kg and a mean break load of 0.589 (0.249) kg, whereas the respective values for the CFL were 0.323 (0.198) and 0.167 (0.063) kg (P < 0.05). Similarly at 12 weeks, TVT had a greater mean maximum average and break load than CFL, at 0.742 (0.052) and 0.274 (0.126), and 0.737 (0.056) and 0.185 (0.128) kg, respectively.

CONCLUSION

This is the first study to assess the tensile properties of the currently used sling materials, TVT and CFL, in an in vivo model. TVT has a greater break load and maximum average load than CFL; the tensile strength of these materials does not decrease with time.

Long term follow up of the cruciate fascial sling for women with genuine stress incontinence

OBJECTIVE

To determine the long term success of the cruciate fascial sling procedure for the treatment of genuine stress incontinence in women.

DESIGN

In 1998, a pre-validated questionnaire was sent to all women who had a cruciate fascial sling between 1979 and 1996 under the care of the senior author at a District General Hospital and in private practice.

PARTICIPANTS

Questionnaires were sent to 246 women; 198 (80%) were returned.

RESULTS

Overall, 142 women felt that they were much improved or cured. The success rate was 74% (95% CI 70%-81%) in women having the sling as a primary procedure and 67% (95% CI 54%-81%) in women having the sling as a secondary procedure. There was no relationship between symptom severity score and age at time surgery, duration of follow up, current weight or body mass index, previous surgery for stress incontinence or concomitant surgery. Of the 103 women with six or more years of follow up, 29 felt that their operation had failed, 16 of whom thought that it lasted between five and 10 years. Urgency was experienced by 29% of women, three needed to perform intermittent self-catheterisation, and 9% found it difficult to empty their bladder. Thirty-seven women (19%) experienced problems that they attributed to the abdominal wound.

CONCLUSION

Although inevitably there are some failures over time, the cruciate fascial sling has good long term success rates. Direct comparison with the literature is impossible, as few studies have relied on properly validated questionnaires.

Treatment of urinary incontinence

The treatment of urinary incontinence is a dynamic and evolving field. New therapies, techniques, and procedures, as well as some subtle refinements in treatments currently used, offer hope for the millions of people suffering from this condition. Recent attention has been directed toward reevaluating the efficacy and durability of some standard treatments for stress urinary incontinence, including pelvic floor exercise, bladder neck suspensions, and pubovaginal slings. Occlusive or supportive devices have evolved into a suitable alternative in some patients. Extracorporeal magnetic therapy and alternative periurethral injectable agents may offer additional treatment strategies for the relief of symptomatic stress urinary incontinence. New drugs for the treatment of overactive bladder and urge urinary incontinence have been introduced recently and, in combination with neuromodulation, offer the first new treatments for this condition in over 25 years. Yet, as rapidly as new therapies become available for the treatment of urinary incontinence, problems have become evident with some that were introduced just a short time ago. Thus, cautious skepticism regarding these "new and improved" treatments should be maintained until long-term data become available with respect to safety, efficacy, and durability.

Preserved particulate fascia lata for injection: a new alternative

BACKGROUND

Preserved particulate fascia lata, derived from screened human cadavers, has recently become available. This injectable form of the material can be injected when soft tissue augmentation is desired. Historically, preserved fascia grafts have proven efficacy and an excellent safety record over the past 73 years.

OBJECTIVE

To examine the clinical response to preserved fascia lata injections in human subjects.

METHODS

Clinical subjects (N = 81; 74 women, 7 men, age range 19-56 years) requiring deep, soft tissue augmentation to repair various cosmetic deficiencies were injected with a total of 109 syringes of preserved particulate fascia lata. Three different preparations-<2.0 mm, <0.5 mm, and <0.25 mm particle sizes-were hydrated in 3-5 cc of 0.3% lidocaine solution and injected with needles ranging in size from 16 to 25 gauge.

RESULTS

The patients were followed for 6-9 months after implantation without incidence of infections, allergic reactions, or acute rejection. After the treatment day, patients experienced no further discomfort. No dermal inflammation was evident and the local echymosis associated with injections was typically minor. Soft tissue augmentation was evident 3-4 months after grafting or longer in most cases.

CONCLUSIONS

This patient series indicates that injectable preparations of preserved fascia lata have the same high biocompatibility as experienced with whole-tissue implants. The safety record of preserved fascia lata implants is reviewed.