The male suburethral sling: remaining questions.

The AdVance transobturator sling represents an important treatment option for male stress urinary incontinence. Accordingly, recent data suggests AdVance to yield success rates of 62%-77% through 3 year follow up.1,2 Although experience to date is favorable, many questions exist. Foremost, the ideal technique for intraoperative placement and tensioning remains a topic of discussion. The exact mechanism by which sling placement restores continence is unknown, but is hypothesized to comprise an elevation of the bulbar urethra both ventrally and cranially. This "repositioning" may then lead to improved urethral coaptation. Concurrently, urodynamic investigation suggests that sling action does not involve an obstructive effect.3 Despite these findings, other investigation highlights the questions that remain regarding sling mechanism of action and the role that urethral compression may place in continence restoration. Accordingly, study of postoperative MRI findings suggests that urethral bulb indentation may be associated with postoperative continence.4 Further, acute urinary retention (AUR) is frequently observed following sling placement, seen in 12%-21% of cases.2,5 Although it is hypothesized that the high rate of AUR may relate to a detrusor muscle deconditioned during prolonged periods of low outlet resistance, a role of urethral compression cannot be excluded. The authors seek to investigate the hypothesis that postoperative AUR may actually be associated with improved continence outcomes. The authors identify continence rates of 100% and 26% in comparison of patients experiencing postoperative AUR versus patients undergoing successful void trial, respectively.6 While this finding is of value, several issues are important to mention. Foremost, additional research is needed to confirm the primary study finding given that prior multivariate analysis has demonstrated that AUR presence/absence was not an independent risk factor for sling failure.7 Second, given some data suggesting that sling success rates deteriorate over time, longitudinal long term investigation is important to determine whether postoperative AUR may be a predictor for durable success rates.8 Finally, assessment of urgency outcomes following male sling placement is important. De novo irritative symptoms and voiding dysfunction following midurethral sling placement in women are a significant concern. Such adverse effects are thought to arise due to an obstructive or irritative effect of the sling. Although the mechanism of action of the AdVance sling is likely different, data regarding urgency outcomes is nonetheless important. This is especially true of patients experiencing AUR postoperatively, even if transient. Despite the many questions that remain, the primary study finding of improved outcomes in patients experiencing AUR is important. Anecdotally, I have observed this tendency in my own practice and believe this to be an observation warranting investigation.