URINARY INCONTINENCE

Should xenograft materials be used in sling procedures?

Giri SK, Hickey JP, Sil D, et al. Long-term results of pubovaginal sling surgery using acellular cross-linked porcine dermis in the treatment of urodynamic stress incontinence. J Urol. 2006; 175:1788–1792.

Several companies market specific products integrated into sling techniques, such as In-First Ultra (porcine dermal matrix secured with bone anchors) and Stratasis (porcine small intestinal submucosa in urethral sling and tension-free versions). Other companies market only the xenograft for application in sling procedures, such as Pelvicol (acellular porcine collagen matrix). However, relatively little information is available to support or discourage use of xenograft materials in sling procedures.

Giri et al found worse outcomes using Pelvicol compared with autologous rectus fascia for pubovaginal slings. With 3-year follow-up, 54% (26 of 48 women) with Pelvicol were considered successfully cured or improved, compared with 80.4% (37 of 46 women) with rectus fascia. Of interest, women continued to report recurrent incontinence with Pelvicol through the 3-year period, whereas women with rectus fascia had recurrence within the first 9 months after surgery.

Midurethral slings: Retropubic or transobturator?

Waltregny D, Reul O, Mathantu B, Gaspar Y, Bonnet P, de Leval J. Inside out transobturator vaginal tape for the treatment of female stress urinary incontinence: interim results of a prospective study after a 1-year minimum followup. J Urol. 2006;175:2191–2195.

Morey AF, Medendorp AR, Noller MW, et al. Transobturator versus transabdominal midurethral slings: a multi-institutional comparison of obstructive voiding complications. J Urol. 2006;175:1014–1017.

Midurethral sling placement was modified from the retropubic to the obturator approach with the objective of reducing the risk of major bladder and urethral injury and vascular complications. Does the obturator approach actually have fewer intraoperative complications compared with the retropubic approach? Unknown. (As noted below, even within retropubic procedures, it is possible—although currently unknown—that vaginal and abdominal approaches have different complication rates.) This is a good news–bad news problem:

Results of the obturator approach are beginning to appear in the literature as case series and uncontrolled comparative studies. Waltregney et al reported cure of stress incontinence in 91% of 99 patients after 1 year of follow-up. Morey et al reported similar continence outcomes: 89% success for 154 patients after the obturator approach compared with 86% success for 350 patients after the abdominal approach, although follow-up in the abdominal group was substantially longer (mean 20 months, range 18–26) than in the obturator group (mean 9 months, range 6–16). Of interest, urethrolysis was performed more frequently in the abdominal group (2.3%) than in the obturator group (0%).

Randomized trials are necessary to obtain unbiased comparisons of techniques. Investigators in the NIH-sponsored Urinary Incontinence Treatment Network are currently performing a randomized trial comparing obturator and abdominal approaches with midurethral slings for women with stress and stress-predominant mixed incontinence. The primary outcome will compare objective and subjective treatment success between the 2 groups at 1 and 2 years after surgery. Enrollment is expected to be complete by early 2008, and 1-year follow-up by early 2009. Stay tuned for the results!

Retropubic midurethral slings: Which brand?

Gandhi S, Abramov Y, Kwon C, et al. TVT versus SPARC: comparison of outcomes for two midurethral tape procedures. Int Urogynecol J Pelvic Floor Dysfunct. 2006;17:125–130.

Lord HE, Taylor JD, Finn JC, et al. A randomized controlled equivalence trial of short-term complications and efficacy of tension-free vaginal tape and suprapubic urethral support sling for treating stress incontinence. BJU Int. 2006;98:367–376.

As the first midurethral sling, the tension-free vaginal tape (Gynecare TVT) has the most evidence and longest follow-up available in the literature. It was originally described using the vaginal approach (“bottom-up”); the company now markets all 3 approaches: vaginal, abdominal (“top-down”), and obturator. Other companies market different products along the same lines, but it cannot be assumed that midurethral slings are interchangeable. Studies are starting to appear that compare different retropubic midurethral slings. In a retrospective case series (Gandhi et al) and a randomized trial (Lord et al), Gynecare TVT had better continence outcomes compared with SPARC (TABLE 2).

TABLE 2

Comparison of 2 retropubic midurethral slings