Sling Incision Research Articles

Treatment of postoperative voiding dysfunction following incontinence surgery

Persistent postoperative voiding dysfunction is a known complication following female stress incontinence surgery. Although many variations on surgical technique exist, the most common cause remains attributable to hypersuspension of the urethra. The diagnosis of postoperative voiding dysfunction in this setting can be challenging due to the lack of standardized criteria and varied clinical presentation. Furthermore, patients can present with a wide spectrum of symptomatology, not merely incomplete bladder emptying or outright retention. The symptoms of urethral hypersuspension can range from purely bladder storage symptoms on one hand (frequency, urgency, or urge incontinence), to the more commonly recognized bladder emptying dysfunction on the other hand (incomplete emptying or frank urinary retention). Although most cases of mild postoperative voiding dysfunction appear to resolve with expectant management, a subset of patients clearly benefit from a sling incision or formal urethrolysis. This leads to prompt improvement or resolution of their postoperative bladder symptoms. The timing of surgery must be determined by the clinician's judgment. However, experience would suggest that postoperative bladder symptoms that persist beyond 4 weeks rarely resolve spontaneously. Within the literature, there has been a paradigm shift toward earlier intervention. Indeed, there are some data to suggest that delayed time to urethrolysis can lead to irreversible bladder dysfunction.

ROLE OF SLING INTEGRITY IN THE RESTORATION OF LEAK POINT PRESSURE IN THE RAT VAGINAL SLING MODEL

We tested the hypothesis that cutting the sling at its suburethral section does not cancel its anti-incontinence effect. We also examined the long-term effects of the sling on bladder function in a recently validated rat model of vaginal sling. Stress urinary incontinence was created in 60 female Sprague-Dawley rats by the previously established method of bilateral pudendal nerve transection. Under anesthesia 20 animals received a vaginal sling, 20 received a vaginal sling in which the suburethral portion of the sling was cut immediately after placement and 20 received a sham vaginal sling. Six weeks after the procedures leak point pressure was determined and a cystometrogram was done using anesthesia in each animal via a previously implanted suprapubic catheter. Kruskal-Wallis and pairwise separate rank multiple comparison tests were performed with a significance level of 0.05. The cut and intact slings increased leak point pressure similarly and these values were significantly higher than that of the sham sling (24.9 and 27.9 cm H2O, respectively, vs 20.7, p <0.0001). Peak micturition pressure was not significantly different among the 3 groups, indicating absent bladder outlet obstruction in the sling groups. Bladder compliance was significantly decreased 6 weeks after placement of a cut or intact sling compared with the sham sling (p = 0.007 and 0.05, respectively). An intact suburethral portion is not a requirement for sling effectiveness in the rat model of stress urinary incontinence. However, the sling procedure decreases bladder compliance. This may explain the observed voiding dysfunction associated with sling procedures.

A New Tension-Adjustment Technique for Sling Operation: An Animal Model

Objective: To investigate the effectiveness of a new tension-adjustment technique for postoperative voiding difficulties encountered after sling operations. Method: To test our new method, urethral obstruction was developed in 5 female dogs by modifying the sling operation by exerting more tension on a specially prepared polypropylene strip in which a gap had been developed. After filling the bladder with isotonic solution, detrusor contractions were induced by pelvic nerve stimulations, and urodynamic studies were performed to document the urethral obstruction. In each case Foley catheters were inserted into the bladder and left in place until the time of tension adjustment. Tension adjustment was performed in the 1st, 2nd, 3rd, 4th and 5th weeks postoperatively for dogs 1, 2, 3, 4, and 5, respectively. Results: On the day of tension adjustment, after filling the bladder with isotonic solution and removing the Foley catheter, none of the dogs, except dog 3, was able to produce a free flow of urine either spontaneously or provoked by detrusor contractions. The release of the prolene sutures was readily achieved in all cases except dog 5. In this case, sling takedown was achieved after surgical exploration in which the sling location was confirmed by following the prolene sutures and Hegar’s dilator. After identifying the sling, the gap was opened by cutting the prolene sutures, instead of a sling incision. Release of the prolene sutures resulted in a distinct drop in the urethra with decreased resistance of Hegar’s dilator. The improvement in voiding was confirmed by postoperative urodynamic studies and was immediate in all cases. Conclusion: Our new technique for postoperative voiding difficulties encountered after sling operation is simple, effective and avoids re-operation in the early postoperative period.

Simple sling incision for the treatment of iatrogenic urethral obstruction

Objectives To review a single-institution experience with sling incision to treat urethral obstruction resulting from pubovaginal sling placement. Urethrolysis involving full mobilization of the urethra has traditionally been used to treat urethral obstruction resulting from a pubovaginal sling. Recently, sling incision has been reported to be a technically simpler, less potentially morbid technique to relieve such obstruction. Methods The charts of 14 women with iatrogenic urethral obstruction from pubovaginal slings who were treated with simple sling incision were reviewed. Presenting symptoms and physical findings and outcomes (primarily resolution of obstructive and irritative symptoms, change in postvoid residual volume, and change in continence status) were evaluated. Results Eleven patients had a biologic sling and three a mid-urethral polypropylene mesh sling. All patients had either obstructive or irritative findings or retention and 10 of 14 had an elevated postvoid residual volume. The average follow-up was 12 months. Overall, 13 (93%) of 14 had complete or significant improvement of presenting complaints, and 1 (7%) eventually required formal urethrolysis. Of the 13 with resolution of presenting complaints, 3 had residual irritative symptoms. Although 3 (21%) of 14 had some element of recurrent stress urinary incontinence, only 1 (7%) required treatment. Conclusions Simple sling incision is an effective, technically simple, and safe treatment for women with iatrogenic urethral obstruction after placement of a pubovaginal sling. Its results are comparable to those of formal urethrolysis, and it may be considered as first-line treatment for iatrogenic obstruction after a sling procedure.

Urethral Erosion After Synthetic and Nonsynthetic Pubovaginal Slings: Differences in Management and Continence Outcome

We present a series of urethral erosion following a pubovaginal sling procedure due to synthetic and nonsynthetic materials and discuss their management and continence outcome. During a 3-year period 57 patients underwent urethrolysis for urethral obstruction after receiving a pubovaginal sling. Urethral erosion, defined as sling material entering the urethral lumen, was present in 9 patients and this cohort comprises the focus of our review. In 3 patients the eroded material was synthetic, that is ProteGen (Boston Scientific, Natick, Massachusetts) in 2 and polypropylene in 1. This condition was treated with removal of the whole sling, multilayer closure of the erosion and selective use of a Martius flap. In 6 patients the eroded material was nonsynthetic, that is allograft fascia in 5 and autograft fascia in 1. This condition was treated with sling incision and multilayer closure of the urethra. Preoperative assessment included a urogynecologic questionnaire, measurement of pad use, a voiding diary, cystourethroscopy and videourodynamics. Postoperatively similar parameters were used to assess continence outcomes and the need for subsequent procedures. Nine patients were followed 30 months after urethrolysis. All 9 women had some manifestation of voiding dysfunction following the pubovaginal sling procedure, including urinary retention in 4, urge incontinence in 3 and mixed incontinence in 2. Urinary retention resolved in 3 patients and urge incontinence resolved in 4. Stress urinary incontinence (SUI) persisted in 2 of the 3 patients in the synthetic group, while no patient in the nonsynthetic group had recurrent SUI. There were no recurrent urethral erosions or fistulas in either group. Urethral erosion after a pubovaginal sling procedure can occur irrespective of the sling material. However, recurrent SUI is not an invariable outcome of the management of urethral erosion following the pubovaginal sling procedure.

Management of urinary retention and obstruction following surgery for stress urinary incontinence.

Urethral obstruction is a potential consequence of all types of anti-incontinence surgery. Not all patients will present in frank urinary retention: the surgeon must have a high index of suspicion to make the correct diagnosis in these cases. Important considerations in the diagnosis of these patients include the timing and methodology of evaluation. Formal urethrolysis in a variety of approaches has demonstrated similar cure rates and recurrent stress incontinence rates. Sling incision may provide an easier and less morbid approach to relieving obstruction caused by a pubovaginal sling with equal efficacy. The procedures are described and recent outcomes discussed.

Early results of pubovaginal sling lysis by midline sling incision

Objectives. To describe a simplified technique and results of pubovaginal sling lysis by incision of the sling in the midline by way of a transvaginal approach. Methods. We reviewed the charts of 19 women who underwent pubovaginal sling lysis for obstruction. Patients presenting with retention, incomplete emptying or storage, or voiding symptoms suggesting obstruction after pubovaginal sling placement were evaluated with videourodynamic studies and cystourethroscopy. The diagnosis of obstruction was made on the basis of a combination of clinical, urodynamic, and endoscopic findings. All patients underwent a midline incision of the sling by way of a transvaginal approach without formal urethrolysis. Results. The mean patient age was 57 years. Fifteen women (79%) had an autologous rectus fascial sling, 3 (16%) an allographic fascia lata sling, and 1 (5%) a polypropylene sling. Twelve women (63%) presented with urinary retention and required catheterization to empty. The other 7 women presented with obstructive and/or irritative symptoms without the need to catheterize. The mean time to sling lysis was 10.6 months from the initial surgery. The mean follow-up was 12 months (range 1 to 55). Overall, sling lysis was successful in 84% of the women. Stress incontinence recurred in 17%. No significant perioperative complications occurred. Conclusions. Pubovaginal sling lysis without formal urethrolysis appears to be a safe and effective method of relieving obstruction. The success and recurrent stress incontinence rates are comparable to those with formal urethrolysis.