After several decades of slow progress, the field of urogynecology is experiencing dynamic change, including:
- new minimally invasive, tension-free, midurethral sling procedures, especially the transobturator approach,
- correction of size-specific defects to repair prolapse, and
- use of mesh/graft augmentation in pro lapse repair.
These developments are some of the most important since Kelly and Dunn first described suburethral fascial plication for stress incontinence and cystocele in 1914.1 They have come about through increased understanding of the pathophysiology of incontinence and prolapse, innovative technology and techniques, and improved communication and coordination among physicians worldwide.
The minimally invasive midurethral sling procedure spawned notable new approaches and is a mainstay of surgical treatment for stress urinary incontinence.
First described in Sweden by Ulmsten in 1995,2 the tension-free vaginal tape procedure is a revolutionary change in the suburethral sling procedure and is now the most widely performed surgery for stress incontinence worldwide.
In it, a tension-free vaginal tape (TVT) (Gynecare, Somerville, NJ) of synthetic polypropylene mesh is attached to 2 needles and passed through a vaginal incision and the retropubic space, exiting to small incisions in the suprapubic region to create a suburethral sling or hammock and provide urethral support during increased abdominal pressure. The sling remains fixed by friction and subsequent adhesions.
Although the traditional suburethral sling was less invasive than other abdominal incontinence procedures, it was associated with a steep learning curve and a high incidence of postoperative irritative bladder symptoms and voiding dysfunction.3
Tension-free vaginal tape: Excellent long-term cure
It can be performed routinely in under 30 minutes using local anesthesia, with minimal postoperative complications. Five-year cure rates approach 95%,4 and data presented at the 2003 International Urogynecology Association clinical meeting describe an objective 7-year cure rate of 82%.5
The incidence and severity of postoperative voiding dysfunction following the TVT procedure is significantly lower than that reported after traditional suburethral sling (2%–40%) or transvaginal needle suspension (2%–50%) procedures.6-9 Although bladder perforation has occurred in up to 10% of patients, reports of complications, including major hemorrhage, tape erosion, and bowel and nerve injury, are rare.10,11
These products have a modified approach, materials, or refinements in technique to address various needs. For example, American Medical Systems (Minnetonka, Minn) introduced the SPARC procedure, which allows abdominal placement of the midurethral sling, similar to a needle suspension technique.
CR Bard (Murray Hill, NJ) introduced a midurethral sling of porcine dermis (Pelvicol) to address concerns physicians may have about using synthetic materials.
Minimally invasive midurethral slings include the Advantage (Boston Scientific, Natick, Mass), Centrasorb (Caldera Medical, Thousand Oaks, Calif), Stratasis TF (Cook, West Lafayette, Ind), and Uretex (CR Bard).
Newest approach: Transobturator sling
In this technique, the sling is placed in the midurethral position, but the insertion points are in the genital area lateral to the vagina, and the needle passes through the obturator membrane and paraurethral space. Because it avoids passage of the needles through the retropubic space, the transobturator approach theoretically should reduce the risk of bowel, bladder, and major blood vessel injury.
The procedure was initially described in Europe and introduced in the United States in 2003. Current product offerings include the outside-in approach of ObTape (Mentor, Santa Barbara, Calif), Monarc (American Medical Systems), and Uretex (CR Bard). Gynecare offers a variation of its TVT—the TVT-Obturator—which involves an inside-out approach to further minimize risk of vascular injury.
Shortage of long-term data, but good early results
In a 1-year follow-up of patients undergoing a sling procedure with the UraTape transobturator sling (Mentor), Delorme and colleagues12 reported that 29 of 32 patients (90.6%) were cured and 3 (9.4%) improved. De Leval13 described his inside-out approach with equally good results: no bladder or urethral injuries and no vascular (hematoma or bleeding) or neurological complications. A transobturator technique using porcine dermis has also been described.
Tension-free vaginal tape versus transobturator sling
In 2004, a small randomized, prospective trial of TVT (n = 29) versus transobturator tape (n = 27) with 1-year follow-up found the transobturator approach to be safer and easier to place with equivalent short-term results.14 Mean operative time was significantly shorter in the transobturator group (15±4 minutes versus 27±8 minutes, P <.001).
No bladder injury occurred in the transobturator group versus 9.7% (n = 3) in the TVT group (P >.05). The rate of postoperative urinary retention was 25.8% (n = 8) in the TVT group versus 13.3% (n = 4) in the transobturator group (P >.05). Cure rates were similar for the TVT and transobturator groups: 83.9% versus 90%, respectively), improvement (9.7% versus 3.3%), and failure (6.5% versus 6.7%). No vaginal erosion occurred in either group.