Surgical procedures for women with SUI are designed to improve pelvic floor anatomy stability and correct urethral closure to increase urethral closure pressure. In 1914, Kelly first used the folding method to improve the vesicourethral segment, curing mild stress urinary incontinence. Since then, many surgical methods have been reported successively. Currently, more than 200 surgical methods for SUI treatment have been reported in the medical literature. Transpubic retrovesiconeck urethral suspension (MMK) and trans-pubic retro-urethral fixation and suspension (Burch) were the first surgical procedures to use a suprapubic approach to raise the paraurethral tissue and fix it to Cooper's ligament or the periosteum of the pubis. These two procedures were used as the first-line treatment for SUI in the past, but other procedures later replaced them due to the high incidence of postoperative complications of retropubic vesiconeck sling (MMK) and a large amount of intraoperative bleeding and long postoperative recovery.
Transvaginal middle urethral suspension (tension-free vaginal tape, TVT) was first proposed by Ulmsten et al. in Sweden in 1996 as a new surgical method for treating women with SUI. Unlike the traditional surgical treatment principle, it does not restore the angle and position of the urethra nor significantly increase urethral resistance. Instead, it is based on the "hammock theory" to achieve the purpose of urine control by strengthening the supporting force of the female middle urethra. Hence TVT has become the standard surgical method for SUI with less traumatic, short recovery, and high long-term cure rate. However, TVT is performed with a blind needle puncture in the retropubic space, which increases the risk of bladder, intestinal, and vascular injuries[10, 20]. Because of the above shortcomings of TVT operation, De Leval et al. Proposed TO-TVT based on the TVT operation in 2003, which can be further divided into TVT-0 and TOT according to the puncture direction. The advantages of this operation are as follows: (1) The method of implantation is simple: the arc of the bending needle through the sling crosses the subpubic physiological curve, avoiding the retropubic space, bladder, and the blood vessels near the bladder, reducing the potential risk of bladder, urethra, blood vessels, intestine or nerve injury, and shorting the operation time. (2) There is no need for cystoscopy: therefore, it has been routinely used in many hospitals to treat women with SUI, and the treatment effect is satisfactory. At the same time, short learning curve, cystoscopy is not required during the operation, and postoperative recovery is fast. It is a highly repetitive and accurate tension-free urethral sling operation of the amorioclastic foramis. At the same time, TO-TVT is associated with the risk of postoperative complications such as groin pain, reticular erosion, and obturator nerve injury.
In order to further reduce the postoperative complications caused by traditional SUI surgery and reduce the difficulty of surgical operation while ensuring the surgical effect, a single-incision sling (SIS) has been developed. The TVT-Secur sling is one of the earliest clinical applications and one of the most widely studied single-incision sling. However, its therapeutic effect is not as good as standard TO-TVT, so it has been withdrawn from the clinical application. With the continuous improvement of technology, more new single-incision sling products have been applied in clinical practice and produced a considerable clinical effect. After constant optimization and update of suspension systems such as TVT-Secur, Mini-Arc, and Ajust, the SolyxTM demonstrated a high subjective cure rate of 97.4%, comparable to the 98.1༅ subjective cure rate of TO-TVT. Meschina M et al. also pointed out in literature reported that the average follow-up of 63 Solyx single-incision sling patients was 6.5 months, and both subjective and objective cure rates reached 95༅. Lenz et al. suggested that the high cure rate of the Solyx single-incision sling is primarily related to the more substantial grip and optimal placement of the obturator internus muscle provided by the automatic anchor bolt. A previous study also demonstrated that the SolyxTM single-incision sling provides greater tension than the Mini-Arc and Ajust sling.
In this study, among the 54 patients with TO-TVT, one patient suffered obturator artery bleeding during the operation. After re-puncture and compression, the lower extremity on the affected side was immobilization after the operation, and the bleeding stopped. Two patients developed medial thigh pain after the operation, which was improved 3–4 weeks after hot compress therapy. Two patients developed new frequent and urgent urination with or without urgent urinary incontinence, which improved after anticholinergic therapy. Among the above complications, obturator artery bleeding and postoperative groin pain is common in TO-TVT. It is speculated that the obturator vessels and nerves of the obturator canal can be easily damaged during the puncture route. Zahn et al. found in the cadaver puncture experiment that the incidence of groin pain after TOT was lower than that of TVT-O, which was related to the distance between the TOT sling and the obturator canal being farther than that of the TVT-O sling. One of the 38 patients with SolyxTM single-incision sling had postoperative urinary retention, which was a depression in the middle part of the urethra after intraurethral ultrasound examination, which was supposed to be caused by excessive sling tension. After the sling was cut off for a second operation, the symptoms of urinary retention disappeared after connecting the two broken ends with 1 − 0 absorbable suture (Figure 1). For complications of postoperative urinary retention, Mingping Wu et al. suggested adding tension release sutures at one end of the sling. For patients with postoperative urinary retention due to overly tight sling, tension release sutures can be used to reduce the tension and avoid the possibility of a second operation. One month after surgery, the anterior vaginal incision dehiscence due to premature sexual activity, resulting in mesh exposure. The exposed mesh was excised in the outpatient operating room, and the wound was sutured. The patient was treated with estrogen ointment for one month and recovered. One patient had a positive cough-induced test after surgery, which was presumed to be related to severe vaginal tearing during vaginal delivery. However, after evaluation, the symptoms of urinary incontinence were significantly improved compared with preoperative symptoms.
This figure is our own, drawn by Li Shuaishuai and Ashok Raj.
This study showed no significant differences in efficacy, intraoperative blood loss, postoperative residual urine volume, length of hospital stay, and incidence of postoperative complications between TO-TVT and SolyxTM single-incision sling surgery (P>0.05). However, SolyxTM single-incision sling surgery is shorter in operation time and less minimally invasive.
In conclusion, SolyxTM single-incision sling and TO-TVT have similar short-term efficacy and safety, but the former has minor surgical trauma, a short learning curve, and a shorter operation time, worthy of active clinical promotion long-term follow-up is needed for other effects.