UAA Lecture at the Annual Meeting of the 19th Chinese Urological Association

Jae-Seung Paick, MD, PhD
Seoul National University College of Medicine, Korea

It was my great pleasure and honor to have been invited as UAA lecturer for the 2009 CUA meeting at Chengdu. The 16th Annual Meeting of the Chinese Urological Association was held on September 17, 2009 at Chengdu Century City International Convention & Exhibition Center. Nearly 3000 urologists from China as well as many international urologists attended the meeting.

The opening ceremony was chaired by Prof. Wei Qiang, Vice Executive Chairman of the meeting. Prof. Li Hong, Executive Chairman of the meeting delivered a welcome speech. He thanked all the representatives for taking part in the CUA2009 in Chengdu. Over 5000 submitted abstracts, nearly 2500 participants and many outstanding international experts participated in this meeting. Prof. Na Yanqun, CUA President welcomed all the executives and colleagues to Chengdu for the CUA2009. In his address, Prof. Na remarked that China’s urology has made dramatic improvements with efforts from generations of urologists. As an efficient organization, the CUA has made achievements in various aspects this year. In future the CUA will continue to work hard to realize three missions, two goals and to build CME system and promote internationalization for the continuous development of China’s urology.

Ms. Han Xiaoming, CMA Adjunct Secretary General gave high praises on CUA’s achievements. Mr. Chen Wenhua, Vice Governor of Sichuan Province congratulated on the CUA2009’s opening and welcomed all the participants on behalf of the Sichuan government. Prof. Chen Shan, CUA Secretary General announced winners of 2009 Wu Jieping Medical Science Award – Urology: Prof. Sun Guang and Prof. Zhong Weide.

2009 CUA Honorable Membership Certificates were awarded to Prof. Luc Valiquette, SIU General Secretary, Prof. Christopher. R. Chapple, EAU Adjunct Secretary General, Prof. Anton J. Bueschen, AUA President, Prof. Robert C. Flanigan, AUA Secretary, Prof. Peter M.
Thompson, President of the Urology Section, Royal Society of Medicine and Prof. Jae-Seung Paick, KUA President. Prof. Sun said the CUA Honorable Membership is to extend gratitude to executives of international urological organizations who have given great supports to CUA and CUA’s internationalization and to enhance communication and collaborations with those organizations.

After the opening, the invited foreign experts gave wonderful lectures, including Prof. Anton J. Bueschen’s Evolution of Urologic Imaging, Prof. Simon Tanguay’s Management of the small renal mass, Prof. Peter M. Thompson’s The evolution of prostate biopsy and its safety, Anton J. Bueschen’s How American Urology is Taught – The role of the AUA, ABU and RRC and Prof. Wang Run’s Radical Prostatectomy and Penile Dysfunction: still a urological challenge. The conference hall was crowded with representatives who were eager to learn and interact. Various topics ranging from female urology, male infertility to laparosocopy, robotics and single port surgery were presented from various instiutions from China and around the world.

The CUA2009 was a gigantic meeting of great significance not only for CUA’ internationalization and development of China’s urology but also the advancement of urology to the intetrnational standard. Once again, I thank UAA and CUA giving me the wonderful opportunity to participate as UAA lecturer on behalf of UAA.

Herein, I present my abstract for the UAA lecture on “ A Journey to Continence: On the Road to Better Surgery”.

INTRODUCTION
Stress urinary incontinence (SUI) is a debilitating condition. To date, many surgical procedures for the alleviation of SUI have been developed, and most involve the stabilization of the bladder neck and/or the urethra. In 1996, a new surgical technique, dubbed as the tension-free vaginal tape (TVT) procedure, was developed for the amelioration of SUI [1]. Subsequently, the attractiveness of such minimally invasive techniques has led to several modifications of the TVT procedure, including the suburethral polypropylene (SPARC) and the transobturator tape (TOT) methods [2,3].

The underlying rationale shared by these procedures is that the reaction of the tissue to the tape results in the formation of a controlled longitudinal deposition of collagen along the length of the tape [1]. This then creates a collagen scar, which stimulates the urethral support mechanism of the pubourethral ligament. These procedures have shown a great deal of potential and have been associated with increased success rates, while reducing operation times and complication rates. These procedures can be performed with the patient under only local anesthesia, thereby, resulting in attenuated hospital stay and postoperative recovery periods. In this lecture, I will discuss the current use of midurethral slings with a focus on outcomes of these techniques in specific clinical problems.

PREDICTOR FOR OUTCOME IN SUI: MAXIMUM FLOW RATE
There are few data on factors predicting the outcome after midurethral slings, and the effect of patient characteristics including urodynamic findings on the outcome has not been systemically addressed. Thus identifying factors that can be associated with failure of midurethral slings would be of utmost importance.
I evaluated the outcome of the TVT procedure and examined factors predicting the outcome of TVT [4]. A total of 60 women (aged 35–71 years) with at least follow-up of 2 years were included in the study. At the latest follow-up, 50 (83.3%) were cured of SUI. Two patients had new-onset urge symptoms without urge incontinence episodes. Multivariate regression analysis showed maximal flow rate (Qmax) to be associated with 0.9-fold risk of the failure; no other parameters had statistical significance. These findings demonstrate that preoperative low Qmax may be associated with the failure of the TVT procedure.

WOMEN WITH INTRINSIC SPHINCTER DEFICINECY
Currently, the definition and diagnosis of intrinsic sphincter deficiency (ISD) is still unclear. However, maximum urethral closure pressure (MUCP) of less than 20 cmH2O or Valsalva leak point pressure (VLPP) of less than 60 cmH2O has been the urodynamic criteria for the diagnosis of ISD. The former examines the passive urethral tone generated by urethral and paraurethral tissues, and the latter determines active urethral resistance during stress. However, the effect of VLPP on the cure rate for the TVT procedure has not been systemically assessed in previous studies.
 
I evaluated the outcome at least 6 months after the TVT procedure for SUI with low VLPP and identified factors predicting the outcome [5]. A total of 221 women 29 to 80 years old (mean age 55.2) were included. Mean follow-up was 10.5 months (range 6 to 52). Patients were divided into 61 with low (less than 60 cm H2O) and 160 with higher (60 cm H2O or greater) VLPP. The overall cure rate was significantly lower in patients with low vs higher VLPP (82.0% vs 93.1%, p = 0.013). In women with low VLPP, multivariate analysis indicated that urge symptoms and low MUCP were independent factors for treatment failure. These findings suggest that women with urge symptoms and low MUCP should be considered to be at high risk for failure after the TVT procedure when VLPP is less than 60 cm H2O.

WOMEN WITH LOW URETHRAL MOBILITY
Theoretically, the prognosis of the mid-urethral slings is no longer determined by sphincteric competence but rather on urethral mobility, which allows it to bend during exertion because the procedure is no longer placed under the bladder neck but under the middle of the urethra. Thus, one would expect that proximal urethral mobility is relatively more important than sphincteric impairment for the success of the mid-urethral sling procedures. However, a recent study of TVT in vivo demonstrated that the sling may have a tendency to rest in the proximal third of the urethra, rather than directly in the midurethra [6]. In addition, with the TVT procedure, Q-tip angle gradually approached baseline values during the course of 1 year, with the most significant difference from preoperative values noted at less than 4 weeks of follow-up [7].

The effect of proximal urethral mobility on the cure rate for the mid-urethral sling procedures was not systemically assessed in previous studies. Recently, I demonstrated that there was no significant difference of the cure rate between the urethral hypermobility group and the non-hypermobility group in terms of the cure rate for SUI although it was slightly lower in the non-hypermobility group [8]. In this study, urethral mobility decreased after the procedure in women with urethral hypermobility but not in women without urethral hypermobility. Klutke et al [9] and Minaglia et al [10] reported that the cure of SUI using the mid-urethral sling procedure did not require the correction of proximal urethral mobility. These findings suggest that the lack of urethral mobility should not be considered to be at high risk of the failure after the midurethral sling procedures in patients with SUI.

WOMEN WITH MIXED INCONTINENCE
While surgical correction of SUI is associated with long-term success rate, urge urinary incontinence (UUI) remains difficult to treat as independent entities and as co-factors in patients with SUI. The cure rate of UUI in previous studies was somewhat different. However, it must be remembered that differences remain between the studies in terms of study design and patient characteristics such as age groups evaluated, exclusion criteria, follow-up duration and a small number of patients with the presence of uninhibited detrusor contraction during cystometry.

Recently, I evaluated the outcome at least 6 months after the TVT procedure in women with mixed urinary incontinence (MUI) and identified factors predicting persistent UUI after the TVT procedure in these patients [11]. A total of 274 women (SUI in 201 and MUI in 73) with follow-up at least greater than 6 months were included in the study. There was no significant difference in the cure rate for stress induced incontinence between patients with SUI and MUI. However, 12 of 73 patients (16.4%) with MUI had persistent UUI. Thus, the overall cure rate was significantly higher in the SUI group than in the MUI group (95.5% vs 78.1%, p = 0.001). On multivariate analysis, MUCP was associated with a 0.9-fold risk of persistent UUI after the procedure in patients with MUI. These findings suggest that low MUCP may be associated with persistent UUI after the TVT procedure in patients with MUI.

ELDERLY WOMEN
The prevalence of SUI increases with advancing age. In elderly patients, SUI is associated with worse health related quality of life and health status since they have more comorbidities. ISD increases in prevalence with advancing age due to a combination of factors, such as decreased estrogenization, age related atrophy of urethral tissue and increased likelihood of a previous incontinence procedure. In addition, ageing is responsible for modifications at the vesical sphincteric system level resulting clinically in a bladder hyperactivity frequently associated with SUI and a bladder hypocontractility [12]. Thus, treatment of SUI in the elderly population was complicated by the high incidence of detrusor overactivity, voiding dysfunction and ISD. In addition, their surgical management poses a challenge since elderly women are likely to suffer significant pre- and intra-opeative morbidity and have a slower recovery.
 
I evaluated clinical outcomes following midurethral sling procedures in patients 65 years old or older and compared these outcome measures to middle-aged women [13]. A total of 266 women who underwent midurethral sling procedures with at least follow-up greater than 6 months were included in the study. Patients were divided as the elderly group (65 years old or older, n = 60) and the middle-aged group (45–64 years old, n = 206). Although postoperative urge symptoms were more prevalent in the elderly group (25.0%) than in the middle-aged group (6.3%), there were no significant differences between the two groups for the rates of postoperative UUI (p = 0.159). SUI was cured by 91.3% in the middle-aged group and 85.0% in the elderly group, respectively (p = 0.158). These findings suggest that age does not seem to be a significant risk factor for failure of midurethral sling procedures.

OBESE WOMEN
The prevalence of incontinence has been associated positively with body-mass index (BMI). Among the different types of incontinence, SUI is the type most closely associated with BMI. Some authors have reported a generally elevated intra-abdominal pressure of obese patients [14]. Obesity has been anecdotally implicated in an increase in the technical difficulty posed by traditional continence surgery, and may therefore also be associated with a higher degree of surgical morbidity. Thus, obese women are frequently denied treatment due to the surgical difficulty and excess risk associated with their treatment. Often, they are requested to return after achieving a significant weight loss, which many of them find impossible to accomplish. Conventional surgical procedures, e.g. Burch colposuspensions, the Marchall-Marchetti-Krants procedure, or pubovaginal slings, are not only associated with higher morbidity [14], but are also quite a bit more difficult to perform on this group of patients.

I evaluated whether or not the outcome of mid-urethral sling procedures was influenced by BMI in Korean women who suffered from SUI [16]. A total of 285 women, ranging in age from 28 to 80 years, all of whom were followed up for at least 6 months, were ultimately included in this study. The patients were classified as follows: normal weight, 18.5–23 kg/m2; overweight, 23–27.5 kg/m2; obesity, 27.5 kg/m2 or higher. I noted bladder perforations in 11 cases (4.9%, 3.8% and 2.2% in the normal weight, overweight, and obesity groups, respectively; p = 0.449). I determined there to be no significant differences among the three groups with regard to cure rate (p = 0.173). The rates of postoperative urinary retention were 9.9% in the normal weight group, 10.1% in the overweight group, and 15.6% in the obesity group (p = 0.396). I determined there to be no significant differences among the three groups with regard to the persistence of urgency (p = 0.312). Seventy-nine patients (27.7%) exhibited symptoms indicative of voiding disorder (hesitancy, poor flow, or sensations of incomplete emptying). The postoperative development of these voiding symptoms was not significantly different among the three groups (p = 0.106). These results demonstrate both the feasibility and the safety of mid-urethral sling procedures for obese Korean women who suffer from SUI. A

WOMEN WITH RECURRENT SUI FOLLOWING MID-URETHRAL SLINGS
Recurrent SUI after midurethral slings is usually due to placing the tape too loosely, so that it becomes slack with time, or the mid urethral tape is misplaced. It can be treated with secondary major anti-incontinence surgery, such as conventional colposuspension, the classic sling procedure and repeat midurethral sling surgery. However, little data is available regarding an effective treatment for patients suffering from recurrent SUI who have already undergone midurethral sling procedures. In addition, conventional repeated anti-incontinence operations are often difficult and may cause scarring and fibrosis in the space of Retzius, distorting the anatomical planes that increase the risk of lower urinary tract injury.
To date, although little data is available regarding an effective treatment for patients suffering from recurrent SUI who have already undergone mid-urethral sling procedures, the shortening technique may prove to be effective in the treatment of failed TVT procedures. I reported the results gathered in a trial of the shortening techniques [17,18]. In these patients, the tape was shortened by the use of clips. Mean follow-up time after the shortening operations was 9.9 months (range 6–18). The tape-shortening technique was conducted with nine patients. Seven of these patients recovered their continence, and no one patient experienced any urinary retention or other voiding difficulties. Two patients reported only minimal stress leakage and elected to undergo no further interventions. These findings suggest that tension plays a substantial role in tension-free mid-urethral sling procedures.

CONCLUSION
Based on the long-term data on safety and efficacy, the evidence so far appears to be in favour of midurethral slings as the minimal-access technique of choice for SUI. Clearly, progress in the management of SUI has occurred based on prospective and randomized controlled trials, and the growing interest for this field suggests that this beneficial trend will continue. Further well-designed trials with standardized outcomes are required to draw accurate conclusions.

REFERENCES

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