Mid-urethral tapes: which? Review of available commercial mid-urethral tapes for the correction of stress incontinence.

This paper reviews the background, development and clinical and urodynamic results of mid-urethral tapes (MUTs) from the first, which was the tension-free vaginal tape (TVT), to the development of the next generation of MUTs, the transobturator tapes. Many of the results of the clinical studies are not statistically significant because of small numbers and an inadequate length of follow up. Overall the MUTs are an important advance on the conventional and more invasive continence surgery, needing only a local or spinal anaesthetic with 24-h hospitalisation and a rapid recovery and return to work. The longest follow up studies indicate good continuation rates for continence, with minimal postoperative and follow up complications. Because of the potential for tape erosion, careful subjective and objective long-term follow up should be maintained. The brilliant and innovative concept of the correction of urethral sphincter incompetence (USI) was described by Ulmsten et al. in 1996. The underlying theory was proposed by Petros and Ulmsten in 1990, leading to intense animal and clinical studies and resulting in the first commercial device, the TVT (Gynecare, Johnson and Johnson). Its basis is mid-urethral support, challenging the previous concept of bladder neck elevation, as the mode of correction of USI. It is likely that both mechanisms can work, although the latter is more likely to lead to voiding disorders. The procedure is simple, safe, effective and speedy, and can be carried out under local anaesthetic with sedation, epidural or general anaesthetic. The tape does not have to be sutured in place and no catheter is required, unless there has been bladder penetration or other surgical procedures are involved. It can be a day-case or 24-h stay procedure. There are minor peri-operative complications, and the cure rate at 5 years is 85%, falling to 81% at 7 years. The currently available MUTs are shown in Table 1 and include the newer obturator tapes, which pass horizontally from one obturator fossa to the other. The TVT was the first commercially available MUT and remains a market leader (Fig. 1). The tape is made of monofilament polypropylene with a pore size of 50 microns. It is placed by vaginal insertion only, and published papers confirm the ease of operability, minimal operative and postoperative complications and satisfactory long-term cure rate. Perhaps the best designed and thorough multi-centre surgical randomised controlled trial (RCT) was from Ward and Hilton, comparing the TVT and colposuspension (Table 2). The study by Levin et al. reflects the findings of most clinicians (Table 3). Yeni et al. (2003) studied the effect of TVT on sexual function in 32 sexually active women with urethral sphincter incompetence, and 24 controls. The index of female sexual function (IFSF) was used as a scoring notation. They found no change in the desire and arousal but orgasm, overall satisfaction and pain decreased. The incidence of coital incontinence fell from 28% to 6%. In the UK NICE (National Institute of Clinical Excellence), the UK regulatory body, has stated in its guidance that ‘TVT may be used when conservative management has failed, and should take into account whether the family is complete’. Whilst this is a recommendation, it seems to ignore the wishes of some patients who might prefer an ‘instant’ cure rather than wait for pelvic floor exercises to work. Similarly some might feel that their incontinence is bad enough between pregnancies to warrant treatment at that stage knowing that, if the TVT is successful, they may have to undergo an elective Caesarian section subsequently to preserve the continence mechanism. The disadvantages of the TVT include an awkward disposable handle – far better to have retained the original TVT with the re-usable handle – and, more importantly, the tape when pulled can narrow and shred at its edges. In response to concern that the sharp needle insertion for the TVT is traumatic, TYCO developed its Intravaginal Sling (IVS) tunneller. The technique is similar to the TVT. The tunneller has a blunt tip (Fig. 2) and is disposable. The tape is made of knitted polypropylene polymer, designed to elicit minimal inflammatory response whilst encouraging fibrous tissue ingrowth. As yet there have been no RCTs, but mostly anecdotal reports. Ingeniously, the same inserter and tape may be used for vaginal vault prolapse as a posterior intravaginal sling. Both TVT and IVS are inserted vaginally. Some clinicians feel that a ‘top–down’ insertion, from the suprapubic region to the vagina, is safer and allows the operator greater control and less chance of bladder injury. In BJOG: an International Journal of Obstetrics and Gynaecology December 2004, Vol. 111, Supplement 1, pp. 41–45