Synthetic Slings

There are several obvious advantages of using synthetic materials for slings. The supply of artificial material is unlimited in quantity, consistent in quality, and can be fashioned into any size or shape. The use of synthetic materials obviates the need for harvesting tissue from a second operative site and minimizes dissection when compared with biomaterials; synthetic materials are more uniform, more consistent, and more durable. In addition, artificial graft materials are sterile and free of biomaterials. The ideal synthetic sling material should be of consistent strength and quality, nonabsorbable, mildly elastic, and easily available in adequate sizes. It should also be at minimal risk of evoking a foreign body inflammatory response and erosion into surrounding structures. No such material exists at present. The drawbacks of synthetic graft materials include graft infection, erosion into the urethra, or extrusion into the vagina.

Short-term objective cure rates range between 73% and 93%.17 Intermediate and long-term results suggest that the continence rate at 10 years is similar to that at 1 year.17,18

The first slings were made of multifilament polyethylene (MersileneTM; Ethicon, Somerville, NJ) to support the urethra and bladder neck. These were replaced by monofilament polypropylene grafts such as Marlex™ (C.R. Bard, Cranston, RI) and Prolene (Ethicon), which were designed to overcome urethral fixation and scarring. The interwoven mesh acts as scaffolding into which the patient's endogenous tissue can grow and galvanize the repair. Consequently, the larger pore size of polypropylene grafts leads to lesser scarring than the polyethylene. Many of the same complications occurring with polyethylene were seen with polypropylene, including urethral erosion, chronic retention, and postoperative urgency and frequency. Gore-Tex (WL Gore and Associates, Flagstaff, AZ) is another synthetic sling, which is made of expanded and reinforced polytetrafluorethylene. Problematic graft infection, rejection, and erosion resulted from its use. A Silicon sling was introduced in 1985 and thought to be superior to MarlexTM or MersileneTM because of its smooth surface, which would promote formation of a fibrous sheath. Although initial cure rates were promising, long-term results were disappointing. Silicone slings have a high rate of vaginal erosions and sinus formation.10 Additional synthetic sling materials have been used and have also met with high complication rates. ProteGenTM (Boston Scientific, Natick, MA) is a woven polyester sling treated with bovine collagen, and was associated with unacceptable rates of vaginal and urethral erosions.

In 1993, Ulmsten and Petros proposed the Integral Theory, postulating that stress and urge are defective flow symptoms that may arise from laxity in the vagina or its supporting ligaments. Using this theory and the hammock hypothesis previously proposed by DeLancey and Richardson,11 Ulmsten et al. postulated that re-creation of the pub-ourethral ligament and support of the suburethral vagina are essential in treating SUI. This finding led to development of the original tension-free urethropexy, the intravaginal slingplasty, and later the transvaginal tape. Tension-free vaginal tape (TVT) (Ethicon, Inc.) is another type of synthetic suburethral sling, which was introduced by Ulmsten and has achieved popularity. Since its introduction in the treatment of SUI, TVT has gained wide acceptance because of its simplicity, ability to be performed under local anesthesia, decreased operative time, decreased recovery, and good outcomes. Ulmsten et al.12 described an 86% cure rate with significant improvement in another 11% in a 3-year follow-up.

The TVT sling is placed at the mid urethra. The rationale behind transvaginal tape is that a tissue reaction to the polypropylene mesh tape produces a controlled longitudinal deposition of collagen along the length of the tape, forming a collagen scar that stimulates the urethral support mechanism of the pubourethral ligaments. This scar secures proper fixation of the mid urethra to the pubic bone and simultaneously reinforces the suburethral vaginal hammock and its connection to the pubococcygeus muscles. Bladder perforation is the most common complication of this procedure. In an effort to reduce this complication, downward needle-carrier placement through the retropubic space, such as the SPARCTM (American Medical Systems, Minneapolis, MN) female sling system was introduced in 2001. The manufacturer of the traditional TVT also recently introduced suprapubic needle passers. However, because these slings still require passage through the retropubic space, their use may lead to vascular, bowel, and bladder injury, and cystoscopy is still required. In France in 2001, Delorme introduced a new approach for placement of sling through the obturator foramen. The aim of this approach is to substitute the lost hammock action and support to the mid urethra as described by DeLancey11 and provide a backboard support to the urethra without penetration of the retropubic space. It is a perineal approach compared with the retropubic approach, avoiding the pelvic cavity. It is ideal for obese patients or those with previous retropubic surgery. The tape trajectory runs deeper and parallel to the deep perineal membrane, and below the pubocervical fascia and levator ani muscles, providing support and minimal urethral compression, and is less obstructive than retropubic slings. Delmas et al.13 studied the tape trajectory in 10 fresh female cadavers, after passing it in a fashion as performed clinically. The tape is located at the medial and inferior border of the obturator foramen and away from the lateral and superior femoral vessels. It is 1 cm away from the insertion of adductor longus and gracilis muscles. The obturator vessels and nerves are situated far on the opposite side of the obturator foramen, and directed toward the thigh. At the perineum, the tape is in a deeper plane to the urogenital triangle with its pudendal nerve branches, including the branches to the clitoris. These branches are protected by the ischiopubic ramus. Laterally, the tape passes under the levator ani muscles and endopelvic fascia, but over or below the arcus tendinous fascia pelvis and 4 cm away from the obturator neurovascular bundle. The accessory puden-dal artery (3% of population) runs above the levator before it exits under the symphysis pubis.

The transobturator route transverses muscles and fascia, with no major vessels, nerves, or viscera along the needle route. At Cleveland Clinic Florida, we use the transobtura-tor approach for placement of Ob Tape™ (Mentor, Santa Barbara, CA) and Monarc™ (AMS) slings. The senior author uses this approach with Ghoniem pinch maneuver. In this technique, the patient is placed in the lithotomy position, under local, general, or regional anesthesia. The anterior vaginal wall is infiltrated with 1: 1 mix of 0.5% bupivacaine hydrochloride and 1% lidocaine hydrochloride with diluted epinephrine (1: 100000) to facilitate dissection and hemostasis. The incision sites extending lateral to the urethra and up to the vaginal sulcus are infiltrated. The incision is made at the level of the mid urethra enough to introduce the index finger. The dissection is performed to the lateral vaginal sulcus until the inner aspect of the ischiopubic ramus is felt with the index finger. The ischiop-ubic ramus is felt, and the inner edge of the obturator foramen is pinched between the thumb and the index finger "pinch maneuver" (Figure 6-3.1). Once a good pinch is achieved, all the following steps are performed in this position.

The skin is punctured with a 15-blade knife 1 cm above the external meatus level and at the level of the clitoris. The puncture site is directly above the thumb and at the inner edge of the ischiopubic ramus. The passer is inserted in two movements/steps guided by the index finger (Figure 6-3.2).

The first step is up and down penetration of the obturator membrane with a distinct "give away" feeling. Once the tip of the passer is felt with the index finger, the passer is rotated from a lateral to medial direction and guided to the vaginal incision. It is kept on the ventral surface of the finger to protect the urethra at all times. The end of the tape

Figure 6-3.1. The inner edge of the ischiopubic ramus is pinched between the index finger (inside the incision) and thumb on the skin. (Reprinted with the permission of The Cleveland Clinic Foundation.)

is threaded into the eye of the passer and is pulled through to bring the wider portion of the tape for a better hold (Figure 6-3.3).

The passer is then pulled in a reverse movement, bringing the end of the tape through the punctured skin. The same steps are repeated on the contralateral side. The ends of the tape are pulled and the midportion of the tape (narrow) is kept under the urethra. Appropriate tension is achieved when a space between the urethra and tape is

Figure 6-3.2. The ventral aspect of the index finger should guide the tip of the passer from the lateral position through the vaginal incision. (Reprinted with the permission of The Cleveland Clinic Foundation.)
Figure 6-3.3. The narrow end of the tape is threaded into the eye of the passer and pulled until the wider portion of the tape is secured into the eye of the passer. (Reprinted with the permission of The Cleveland Clinic Foundation.)

ensured using a clamp. The ObTapeTM is nonelastic and does not recoil. The ends of the tape are cut, by pressing on the skin, avoiding tension on the tape. Skin adhesive is applied to the punctured sites, and the vaginal incision is closed with 2-0 polyglactin 910 suture.

In case of a cystocele repair, the transobturator tape (TOT) or sling can be placed through the same incision. It is preferable to fix the edge of the tape on each side of the urethra to the pubocervical fascia to prevent early movement of the tape.

Transobturator tape is effective for treatment of stress urinary incontinence.14 Delorme15 reported his satisfactory initial feasibility and safety study on 40 patients with a follow-up of 3 to 12 months, and more recently on 32 patients with a minimum of 1-year follow-up (mean 17 months).16 He reported cure in most of his patients with failure in only one patient.

We obtained promising initial results when we evaluated 27 women with SUI who underwent transobturator ObTapeTM at our institution. Eight of the patients underwent TOT alone and 19 had TOT with other pelvic reconstructive procedures. There were no urethral or bladder injuries. Vaginal erosion was seen in one patient, and it was treated by local excision and closure. No bowel or vascular injuries occurred. Incontinence was cured or improved in more than 80% of patients.

Herbal Remedies For Acid Reflux

Herbal Remedies For Acid Reflux

Gastroesophageal reflux disease is the medical term for what we know as acid reflux. Acid reflux occurs when the stomach releases its liquid back into the esophagus, causing inflammation and damage to the esophageal lining. The regurgitated acid most often consists of a few compoundsbr acid, bile, and pepsin.

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