Niels Klarskov

Utility of invasive urodynamics before surgery for stress urinary incontinence

The utility of invasive urodynamic testing in the preoperative evaluation of womenwith stress urinary incontinence (SUI) has been challenged by two recent randomized controlled trials (RCTs) [1, 2] that could not document any gain on outcome of surgery. However, both studies have common methodological issues that make it difficult to draw a general conclusion. Urodynamics (UDS) is defined by the International Continence Society (ICS) as the study of the function and dysfunction of the urinary tract by any appropriate method [3]. Accordingly, UDS is the only way to understand why people are continent or incontinent. Treatment that is not carried out blindfolded but based on knowledge requires (noninvasive and/or invasive) UDS [4]. It is well documented that invasive urodynamic testing (in terms of cystometry and pressure-flow study) in women with predominant symptomatic SUI may show either detrusor overactivity (DO) solely or genuine SUI in combination with other urodynamic findings, such as DO and/or voiding difficulties (in terms of obstruction or hypoactive detrusor function). In addition, urethral profilometry or leak-point pressure allows identification of individuals with low urethral pressure [i.e., intrinsic sphincter deficiency (ISD)]. The surgeon who wishes to acquire this knowledge needs to use invasive UDS. Invasive UDS has principally two goals: to confirm clinical and noninvasive UDS impression; to identify parameters that may alter diagnosis or treatment. However, prerequisites for taking advantage of invasive UDS imply:

Effect of fesoterodine on urethral closure function in women with stress urinary incontinence assessed by urethral pressure reflectometry

Introduction and hypothesisThe aim was to evaluate, using urethral pressure reflectometry (UPR), the effect of fesoterodine on urethral function in women with stress urinary incontinence (SUI).MethodsWomen aged 18 to 65xa0years were eligible for this randomised, double-blind, placebo-controlled, crossover study if they had had clinically significant SUI or SUI-predominant mixed urinary incontinence for >3xa0months. Each participant received fesoterodine 4xa0mg, fesoterodine 8xa0mg, and placebo once daily for 7xa0days, with a 7- to 10-day washout between treatments. UPR was performed at baseline and 4 to 8xa0h after the last dose in each treatment period. Participants completed a 3-day bladder diary before randomisation and during the last 3xa0days of each treatment period.ResultsOf the 22 women randomly assigned and treated, 17 met the criteria for the primary efficacy analyses. No statistically significant differences were seen between fesoterodine 4xa0mg or fesoterodine 8xa0mg and placebo in opening urethral pressure (primary endpoint) or other UPR endpoints. No statistically significant differences were seen between either fesoterodine dose and placebo in the change from baseline in the bladder diary variables (total urinary incontinence, SUI, or urgency urinary incontinence episodes per 24xa0h). Adverse events were reported by 8 participants taking fesoterodine 4xa0mg, 17 taking fesoterodine 8xa0mg, and 8 taking placebo.ConclusionsFesoterodine did not affect urethral pressure or significantly decrease the number of incontinence episodes in women with SUI. The UPR parameters showed no placebo effect, while there was a placebo effect of 60xa0% based on the bladder diary.

Re: Does preoperative urodynamics improve outcomes for women undergoing surgery for stress urinary incontinence? A systematic review and meta‐analysis

1 Schuit E, Stock S, Rode L, Rouse DJ, Lim AC, Norman JE, et al. Global Obstetrics Network (GONet) collaboration. Effectiveness of progestogens to improve perinatal outcome in twin pregnancies: an individual participant data meta-analysis. BJOG 2015;122:27–37. 2 Harris J, Kearley K, Heneghan C, Meats E, Roberts N, Perera R, et al. Are journal clubs effective in supporting evidence-based decision making? A systematic review. BEME Guide No. 16. Med Teach 2011;33:9–23. 3 Chambers GM, Wang YA, Chapman MG, Hoang VP, Sullivan EA, Abdalla HI, et al. What can we learn from a decade of promoting safe embryo transfer practices? A comparative analysis of policies and outcomes in the UK and Australia, 2001–2010. Hum Reprod 2013;28:1679–86. 4 Human Fertilisation and Embryology Authority (HFEA). National Data 2013. Finsbury Tower, London: HFEA. [www.hfea.gov.uk/9461. html]. 17 December 2014. Accessed 22 February 2015.

Utility of invasive urodynamics before surgery for stress urinary incontinence: response to correspondence

We thank Sanne van Leijsen et al. [1] for their comments on our editorial [2]. They point out that we did not include the Value of Urodynamics before Stress Urinary Incontinence Surgery (VUSIS) II study in our editorial; unfortunately, however, the VUSIS II study also used a design that is unfit for evaluating the value of invasive urodynamics (IUD). The hypothetical example below illustrates why we find the study design unfit. If a group of doctors were convinced that standard treatment with a standard dose of an ACE inhibitor to all patients is the best prevention of stroke, regardless of blood pressure, they could convince themselves that they are right with the following randomized study. One group was treated according to the doctor’s choice based on office evaluation alone and the other group was also treated according to the doctor’s choice, but this group had both office evaluation and their blood pressure measured. As the doctors were convinced that the ACE inhibitor in a standard dose was always the best treatment, the patients in the two groups would end upwith exactly the same treatment and the results would be the same in the two groups. The “surprising” conclusion would be that measurement of the blood pressure has no value in the prevention of stroke; the result is inborn in the design. The three recent randomized control studies [3–5] based on doctors’ choice have demonstrated that the group of clinicians involved did not actually use urodynamics in their decisionmaking and essentially all patients ended up with a midurethral sling. Therefore, the negative outcome is given in advance (whether valid or not) because of the design. Consequently, the results are not generalizable and cannot be extrapolated to other doctors/centers. If the studies, on the contrary, were performed by doctors who strongly believed in IUD and based their choice of treatment on IUD alone, it would be expected that the result in the IUD group would be either better or worse than in the group without IUD, depending on whether the doctors’ theory was right or wrong. At themoment we do not knowwhat the best treatment is for “uncomplicated stress incontinence”with the urodynamic findings of detrusor overactivity (DO) or impaired voiding efficiency. The VALUE/VUSIS studies may lead clinicians to believe that a standard midurethral sling will always be a successful treatment, which is not necessarily true. The three randomized controlled studies were not designed to answer these questions. We appreciate the supportive and inspiring comments from Dr. Petros [6].

A faster urethral pressure reflectometry technique for evaluating the squeezing function.

Abstract Objective. Urethral pressure reflectometry (UPR) has shown to be superior in evaluating the squeeze function compared to urethral pressure profilometry. The conventional UPR measurement (step method) required up to 15 squeezes to provide one measure of the squeezing opening pressure and one measure of the squeezing elastance. The UPR technique was modified (so the examination last 7 s), requiring only one squeeze for the measurement to be made (continuous method). The aims of the study were to compare the UPR parameters measured during squeezing by the continuous method with measurements made by the step method and to measure the reproducibility of the continuous method. Material and methods. In total, 33 women were included (eight healthy and 25 with urodynamically proven stress urinary incontinence). The women were measured twice with the step method followed by five measurements with the continuous method. Results. No significant difference was seen between the mean squeezing opening pressures measured with the two methods. The squeezing elastance was significantly higher (p < 0.00001) with the continuous method (2.7 cmH2O/mm2) than with the step method (1.9 cmH2O/mm2). The coefficient of variation (CV) was 6.5% for the opening pressure measured with the continuous method and 14.8% for the squeezing elastance. Conclusions. A new method for performing UPR measurements during squeezing has been described. With the new method a UPR measurement can be conducted during only one squeeze. The squeezing opening pressure is the same while the squeezing elastance is higher with the new method compared with the conventional method.

Preoperative voiding dysfunction is a risk factor for operative failure according to the VALUE study

TO THE EDITORS: We read with interest “Trends in urodynamics study utilization in a Southern California managed care population” by Lippman et al. In the introduction, the authors state “in patient with demonstrable stress incontinence on office evaluation and normal post-void residuals, urodynamic measurements were not predictive for success and did not predict voiding dysfunction.” This is a misinterpretation of the VALUE (Value of Urodynamic Evaluation) study, which potentially is damaging for our patients; unfortunately, this message is scattering via different journals. Midurethral slings are potentially obstructive procedures that carry a special risk in patients with preexisting voiding dysfunction. The VALUE study was not designed to elucidate this risk. However, subgroup analysis confirmed the increased risk of poor outcome. Thus, only 62.1% of the patients with voiding dysfunction (as defined by the authors) met the primary outcome measure compared with 78.3% of the patients without voiding dysfunction. Clinically, this is a highly significant difference, although statistically borderline (P 1⁄4 .064), but it is important to realize that only one-half of the entire population was included in this subgroup analysis; thus, the statistical insignificance is thereforemost likely due to a lack of power (a type 2 error). In our view this should be taken seriously, and patients with preexisting voiding dysfunction should be informed at least about the increased risk of poor outcome and offered an opportunity to decide for alternative treatment. Voiding dysfunction is defined as abnormally slow and/or incomplete micturition. The only objective way to find out whether the patient has voiding dysfunction is by noninvasive urodynamic screening in terms of uroflowmetry and postvoid residual urine volume measurement and eventually invasive urodynamics, to sort out whether a patient has obstruction or hypoactive detrusor function. Urinary incontinence symptoms are unreliable as to the underlying dysfunction, thus, women with mixed symptoms (even pure stress incontinence) may present underlying pure detrusor overactivity or different combinations of stress incontinence with or without detrusor overactivity and with or without voiding dysfunction. The preoperative work-out depends on the complexity of symptoms. In most cases, simple noninvasive screening for voiding dysfunction will do it. However, if maximum flow rate is decreased significantly, if the flow pattern is repeatedly abnormal, and/or if postvoid residual is repeatedly increased, there will be an indication for invasive urodynamics. Voiding dysfunction does not necessarily exclude a midurethral sling, but the patient obviously needs to be informed sufficiently about the decreased success of surgery in this situation. -

Authors’ reply to the comment by Petros et al. on “Retropubic versus transobturator MUS: Time to revisit?” by Lose and Klarskov

We thank Peter Petros for his comments, although it is somewhat difficult to follow his argumentation for the anatomical basis for the higher failure rate after transobturator mid urethral slings (T-MUS).We do not think that Poiseuille’s law can be used to explain incontinence, as the assumptions is not fulfilled; the law is true for steady flow in a rigid pipe. However, the urethra is definitely not a rigid pipe, and there is no steady flow during stress episodes. No clinical or urodynamic data indicate that retropubic MUS (R-MUS) and T-MUS have different mechanism of action; however, biomechanically, R-MUS provide stronger support than T-MUS, which can be illustrated with the following simple figure based on sound physical principles, which imply that all forces are in full balance (equilibrium) (Fig. 1). Niels Klarskov, Gunnar Lose, Werner Schaefer