Synthetic Midurethral Slings and the Attractiveness of TOT

Cystoscopy does not need to be performed routinely as it does with TVT, but the key here is the word “routinely.” Whether or not cystoscopy is used is really dependent on the operator's judgment.

Vincent Lucente, M.D.: The Inside-Out Approach to TOT

The inside-out technique, which I use, was developed for the purpose of even further minimizing risk to the urethra and bladder and ensuring minimal dissection of the vaginal tissue.

Although Dr. Delorme's outside-in procedure was indeed a significant development for the treatment of stress urinary incontinence—and although most available studies show that the two approaches are similar in safety and efficacy—there have been several clinical reports and anatomical studies documenting that bladder and urethra injuries still occur with the technique.

This remaining potential for injury prompted Dr. Jean de Laval, of the University of Liège (Belgium), to develop an alternative TOT approach that he believed would be even safer because the TOT needle would travel out and away from the lower urinary tract.

I am convinced that his technique offers several advantages. For one thing, it essentially eliminates any risk of injury to the urethra and bladder. It also avoids potential injury to the anterior branch of the obturator artery, which runs around the outer perimeter of the obturator foramen. In the outside-in procedure, the instruments run along the edge of the foramen and can potentially disrupt that anterior branch. The hematomas that can occur—and there have been some reported—are not at all life threatening, but they can cause a protracted recovery for our patients.

I also believe that whenever we're traversing instruments through the body, we're always most accurate where we start our journey. By starting at the urethra and traveling away, I believe we're going to achieve more consistent and accurate placement of the sling at the midurethral position.

The greatest advantage to the inside-out technique, I believe, is one that has not been documented or well studied but still lingers in my mind. That is, because we need to do less periurethral dissection, we're minimizing the risk of urethral denervation.

The outside-in technique involves more periurethral dissection: One simply must dissect more tissue to assure the palpation guidance of the incoming instruments. Healing and re-enervation do occur, of course, but I believe the dissection inevitably increases the risk of sphincteric denervation, and that women may not get “back to baseline,” so to speak—that they may suffer an insult that could lead later to ISD. It is quite possible that we are denervating the urethra musculature in subtle ways that cannot be measured now but will become apparent 10–15 years later as our patients age. I would rather avoid that possibility.

The key to the inside-out technique is the use of local anesthesia. The procedure enables us to use local anesthesia, fortunately, but it must be utilized thoroughly. Local anesthetic not only must infiltrate the area under the urethra and into the vagina, but it also must infiltrate the skin, fat, and—most importantly—the muscle of the inner thighs. With proper techniques, we can markedly reduce the likelihood of postoperative thigh pain.

The device used in the procedure includes a pair of helical passers that are assembled with polyethylene tubes bound to a polypropylene tape and one winged guide. The guide ensures that the tape will be passed accurately through the obturator membrane without entering the pelvic space.

The points where the needles will exit are identified by tracing a horizontal line at the level of the urethral meatus, and a second line 2 cm above this. The exit points are on this second line, 2 cm lateral to the folds of the thigh. We will make incisions at each exit point once the helical passer hits the skin; for now, we just mark the expected exit points and infiltrate with local anesthetic.

We then make a 1-cm long midline vaginal incision, starting 1 cm proximal to the urethral meatus. We dissect using a push-spread technique, orienting our scissors on a plane slightly above the horizontal, with a 45-degree angle relative to the urethral sagittal plane, toward the upper part of the ischiopubic ramus.

The winged guide is inserted into the tract at the same angle, until it passes the inferior pubic ramus. With the winged guide in place, a helical passer is then inserted into the tract. When the device is pushed slightly, the passer will move through the obturator membrane, at which point it is no longer advanced but rather is simply rotated and swung into position, which allows it to curve around the bone and exit through the thigh.