Thursday, April 19, 2012
Single Incision Slings (TVT-Secur, Miniarc, Ajust)- Are they as good as standard slings?
The short answer is “No”.
Now for some details. In 2006, “minislings” were introduced to the marketplace to meet a perceived demand for something better than standard mesh slings. The mesh sling is not so old to begin with, having really debuted in 1996 as the "TVT" with may similar slings like it currently being used to treat Stress Urinary Incontinence. The TVT represents the retropubic approach to placing slings, while the transobturator approach is the other standard and equally effective method (debuted in 2001) of placing mesh slings. Each has its advantages and disadvantages, but both are widely considered the standard of care in modern surgical treatment of stress incontinence in the US and worldwide. There are varying styles of each, but both methods require placing needle passers, or trocars, through the skin, either in the groin creases or at the pubic hair line in order to properly position the sling.
Single Incision Slings (SISs), or minislings, do not require needles for placement, only the small vaginal incision common to all slings. The purported advantage to such a modification would be shorter operating room time and less post-operative pain. Some people would say “big deal”, but is there a price for too much efficiency? Do SISs match up vs. standard mesh slings in cure of SUI? Do they avoid or lead to more complications? Are they as well studied as the traditional slings?
These are all valid, logical and pertinent questions in light of the recent FDA bulletin on vaginal surgery and mesh. The most recent bulletin addresses only pelvic organ prolapse and mesh and safety concerns (both real and misrepresented). The FDA did not call attention to mesh usage for slings as traditional mesh slings are now considered standard procedures for SUI, but commentary was made on SISs, as they are not well studied.
Many studies have shown that the TVT-Secur is simply an inferior product in terms of cure rate for SUI, when compared to TVT. It has been often shown to be difficult to place reliably, requires a significant learning curve, and proper tension against the urethra is not easy to judge. The cure rates even at 1 year are often 20% less than TVT. Miniarc by comparison has tried to learn these concerns by changing the method of securing the sling around the urethra, and alterations to the sling were made, but the adjustment factor and rates of urinary retention have also made it a technique that is difficult to obtain consistent results. The studies reflect this inconsistency. A newer model of SIS, Ajust, adds a unique twist by allowing the surgeon to adjust it if s/he perceives the sling to be too tight or loose prior to surgical completion. Yet even with adjustment, its cure rate is still inferior. Specific studies can all be obtained on PubMed. In summary overview, a very large meta-analysis of over 750 women undergoing single incision slings was performed, covering all studies (Eur Urol. 2011;60(3):468–480.) up to 2011.
What did it show…?
There were nine randomized clinical trials. Seven studies reported subjective cure rates, while six reported objective cure rates. The overall conclusion of the meta-analysis showed that SISs are associated with lower subjective and objective cure rates. Operating time was shorter and post operative pain was less, but at what cost? In addition, re-operation rates were higher in the SIS group, as well as there was a higher mesh exposure rate with them.
Patient selection for these procedures must be done with discretion, and patients must be counseled about lower success rates, and that data is limited. Quicker is not better.
Posted by Matthew E. Karlovsky, M.D. at 10:34 PM