Mechanism of Postoperative Urinary Continence

Stress incontinence used to be attributed mostly to urethral hypermobility, and consequently most surgical techniques focused on the region of the bladder neck and proximal urethra. This article reviews our knowledge about the mechanism of postoperative urinary continence based on anatomic, imaging and urodynamic studies. Reduction of urethral mobility, as measured by cotton swab testing or imaging studies, is not the only reason why continence surgery succeeds. Imaging techniques are of limited value for elucidating the continence mechanism because radiologic landmarks and criteria are not reproducible. Urodynamically, the increased pressure transmission after successful continence surgery is attributed to the retropubic repositioning of the urethra, its compression against the anterior vaginal wall, and improved transmission of intra-abdominal pressure during stress. The role of the ‘functional’ urethral obstruction remains to be studied. In incontinent patients with hypermobility of the bladder neck and proximal urethra continence can be achieved by surgical correction. However, stress incontinence is possible in the absence of urethral hypermobility, and standard surgical techniques can fail to restore continence in these patients.     

Intraoperative urethral pressure profilometry as an adjunct to bladder neck reconstruction

Between 1975 and 1984 we performed 17 bladder neck reconstructions with bladder neck suspension using intraoperative urethral pressure profilometry. Studies were done intraoperatively after bladder neck reconstruction and then they were repeated after bladder neck suspension. A continence length of 25 to 35 mm. and a urethral closure pressure of greater than 60 cm. water were obtained in all patients. Bladder neck suspension was noted to increase the continence length in all patients and allowed for at least a 2-fold increase in the closure pressures that were obtained. Urinary continence was assessed postoperatively from parental interviews. It seems important to achieve an initial closure pressure of at least 60 cm. water, while at the same time attempting to ensure anterior fixation. Intraoperative urethral pressure profilometry can serve as a valuable adjunct to bladder neck reconstruction by confirming the adequacy of bladder neck resistance after bladder neck reconstruction and again after bladder neck suspension.     

Urodynamic Evaluation of Changes in Urinary Control After Radical Retropubic Prostatectomy

Purpose

Urodynamic evaluations were done in patients before and after radical prostatectomy to obtain more information about the factors that affect continence.

Materials and Methods

Urodynamic testing was done in 82 patients before, and 6 to 8 weeks and 6 months (9 cases) after radical prostatectomy. Evaluation included measurement of cystometric bladder capacity, compliance, functional profile length, maximal urethral closure pressure, maximal urethral closure pressure during voluntary contraction of the external sphincter, residual urine, maximal flow rate and bladder instability.

Results

The continence rate was 33.4, 69.4, 84.7 and 90.9% at 1, 3, 6 and 12 months after radical prostatectomy, respectively. Mean functional urethral length decreased from 61 mm. preoperatively to 25.9 mm. postoperatively, maximal urethral pressure from 89.6 to 65.2 cm. water and bladder capacity from 338.7 to 278.8 ml. Bladder instability was found in 17 and 41% of cases before and directly after radical prostatectomy, respectively. There was a statistically significant difference in maximal urethral closure pressure (68.1 versus 53.1 cm. water) as well as functional urethral length (27.6 versus 20.5 mm.) in continent versus incontinent patients, respectively. Urodynamic examination 6 months after prostatectomy showed an increase in functional profile length and maximal urethral pressure, while bladder measurements did not change significantly.

Conclusions

After radical prostatectomy significant changes in bladder and sphincter measurements are noted. Urethral closure pressure, functional urethral length and bladder stability are significantly urodynamic factors that influence continence after radical prostatectomy.     

Urinary incontinence and voiding dysfunction after radical retropubic prostatectomy (prospective urodynamic study)

AIMS: During this prospective study we analyzed the effects of radical retropubic prostatectomy (RRP) on bladder and sphincter function by comparing preoperative and postoperative urodynamic data. The aim of the study was to determine the reason for urinary incontinence after RRP and explain why one group of patients will be immediately continent after catheter removal, while others need some time to reach complete continence. METHODS: Urodynamic examination was performed in 63 patients 3-7 days before and 2 months after surgery. RESULTS: Forty-three (68.2%) and 53 (84.1%) patients regained continence at 2 and 9 months following RRP, respectively. Ten patients (15.9%) were immediately continent after catheter removal. Urodynamic stress incontinence was detected in 18 (28.6%), and detrusor overactivity incontinence in 2 (3.2%) patients 2 months after surgery. The amplitude of preoperative maximal voluntary sphincteric contractions was significantly higher in the postoperative continent group (125 vs. 96.5 cmH(2)O, P < 0.0001). The patients who were immediately continent following catheter removal had no lower urinary tract symptoms (LUTS) and urodynamic abnormality preoperatively, and they had significantly higher preoperative and postoperative maximum urethral closure pressure (at rest and during voluntary sphincter contraction) than those who became continent later on. CONCLUSIONS: These data suggest that the main cause of incontinence after RRP is sphincteric weakness. In the continent group, those who became immediately continent had significantly higher maximum urethral closure pressure values at rest and at voluntary sphincteric contraction even before the surgery.     

Mechanism of continence after modified Pereyra bladder neck suspension. Prospective urodynamic study

Twenty females with genuine stress urinary incontinence who underwent modified Pereyra bladder neck suspension were urodynamically studied pre- and postoperatively in an attempt to determine the mechanism by which continence was restored. Detailed analysis demonstrated no significant change comparing the pre- and postoperative cystometry findings, uroflow parameters, maximal voiding pressure, urethral resistance, maximal urethral closure pressure, or functional urethral length. The only significant change identified as a result of the surgical procedure was an alteration of proximal urethral pressure transmission during stress from negative to positive gradients. It is concluded that the modified Pereyra bladder neck suspension restores continence by restoring proper urethral support with restoration of positive pressure transmission to the proximal urethra without causing outflow obstruction, changing functional length, or altering maximal urethral closure pressure.     

Do bladder neck mobility and urethral sphincter function differ during pregnancy compared with during the non-pregnant state?

The aim of the study was to assess and compare urethral sphincter (US) function and bladder neck (BN) behavior in pregnant and non-pregnant women. Urethral pressure profile parameters, intravaginal-anal pressures and BN position/mobility were compared in both pregnant and non-pregnant women. It was found that pregnancy results in a decreased maximal urethral closure pressure (MUCP)/area of continence at rest and at stress, decreased pressure-transmission ratio (PTR) values and backwards displacement of the bladder neck. No significant changes in intravaginal-anal pressures and BN mobility/downwards displacement were seen. Compared with stress continent pregnant patients, pregnant patients with stress urinary incontinence (SUI) have a lower MUCP at rest/stress and area of continence at stress, but show no difference in BN behavior. Regression analysis shows no correlation between advancing pregnancy and any of these parameters. It was concluded that pregnancy induces diminished US function and backwards displacement of the BN. Compared to continent pregnant patients, pregnant women with SUI also have a diminished US function. US parameters are not significantly modified by advancing pregnancy.     

Significance of preoperatively observed detrusor overactivity as a predictor of continence status early after robot-assisted radical prostatectomy

Several recent studies have reported the involvement of bladder dysfunction in the delayed recovery of urinary continence following radical prostatectomy （RP）. The objective of this study was to investigate the significance of detrusor overactivity （DO） as a predictor of the early continence status following robot-assisted RP （RARP）. This study included 84 consecutive patients with prostate cancer undergoing RARP. Urodynamic studies, including filling cystometry, pressure flow study, electromyogram of the external urethral sphincter and urethral pressure profile, were performed in these patients before surgery. Urinary continence was defined as the use of either no or one pad per day as a precaution only. DO was preoperatively observed in 30 patients （35.7%）, and 55 （65.5%） and 34 （40.5%） were judged to be incontinent 1 and 3 months after RARP, respectively. At both 1 and 3 months after RARP, the incidences of incontinence in patients with DO were significantly higher than in those without DO. Of several demographic and urodynamic parameters, univariate analyses identified DO and maximal urethral closure pressure （MUCP） as significant predictors of the continence status at both 1 and 3 months after RARP. Furthermore, DO and MUCP appeared to be independently associated with the continence at both I and 3 months after RARP on multivariate analysis. These findings suggest that preoperatively observed DO could be a significant predictor of urinary incontinence early after RARP; therefore, it is recommended to perform urodynamic studies for patients who are scheduled to undergo RARP in order to comprehensively evaluate their preoperative vesicourethral functions.     

Urodynamic changes after radical prostatectomy

Summary Urodynamic examinations were performed in 82 patients with clinically localized prostate cancer before and after radical prostatectomy. A significant decrease in bladder capacity (396 ml to 331.9 ml), urethral closure pressure (89.6 cm H₂O to 65.,2 cm H₂O) and functional profile length (61 mm to 25.9 mm) was noted. The continence rate after radical prostatectomy was 33.4 % after 1 month, 69.4 % after 3 months, 84.7 % after 6 months, and 90.9 % after 12 months, respectively. A correlation was found between urethral closure pressure and functional profile length and continence. A second urodynamic examination was performed 6 months after radical prostatectomy. Functional profile length and urethral closure pressure increased. These data suggest that restoration of continence is based on sphincteric parameters.      

Bladder Neck Mobility and Urethral Closure Pressure as Predictors of Genuine Stress Incontinence

Two hundred and seventy-five consecutive patients with symptoms of lower urinary tract dysfunction underwent urodynamic evaluation, including multichannel urodynamics, urethral pressure profilometry, X-ray and ultrasound imaging. After women with previous incontinence or prolapse surgery or pelvic radiotherapy and those with evidence of urethral kinking on ultrasound had been excluded, 179 datasets were analyzed. Both bladder neck descent (P<0.0001) and maximum urethral closure pressure (P<0.0001) were strongly associated with a fluoroscopic diagnosis of GSI. Only weak correlations between bladder neck mobility and urethral pressure parameters (highest r=−0.17) were observed. Regression analysis yielded a mathematical model that demonstrated a wide spread of odds ratios for GSI for the measured values (from <0.2 to >100). Bladder neck descent explained 29% and urethral closure pressure 12% of overall variability. Both bladder neck mobility and maximum urethral closure pressure are strong predictors of the diagnosis of GSI, provided major confounders are excluded. Bladder neck mobility appears to be the stronger predictor.     

The clinical and urodynamic effects of the tension free bladder neck sling procedure

This study evaluated the clinical and urodynamic findings before and after tension-free bladder neck sling (TBS) procedure with Prolene tape. We enrolled 32 women who underwent TBS for genuine stress incontinence without intrinsic sphincter deficiency or severe uterovaginal prolapse. All subjects received 1-h pad test, Q-tip test, multichannel urodynamic testing, introital ultrasonography, and the Bristol Female Lower Urinary Tract Symptoms Questionnaires before and 1 year after surgery. Of the 32 subjects 27 were cured of stress incontinence, two improved, and three failed. The incidence of irritative symptoms and incomplete bladder emptying were significantly lower after surgery. The mean urethral straining angle showed a significant decrease from 73.8° preoperatively to 30.1° postoperatively. At rest the postsurgical position of the bladder neck (BN) was localized more cranially. During straining both ventral and caudal mobility of the BN decreased significantly following TBS, causing a more cranial and dorsal position of the BN. Urodynamic parameters including functional urethral length, maximal urethral closure pressure, and pressure transmission ratio showed significant increases after surgery. TBS could decrease the hypermobility of the BN and restore the BN support to prevent urinary leakage during straining, instead of urethral obstruction. The subjective and objective cure rate of stress incontinence is 84%, similar to those results reported after retropubic urethropexy and tension-free vaginal tape procedure. It is also worth emphasizing that no postoperative urinary retention occurred, although the limited number of cases makes it hard to confirm the significance of findings over the retention rate of tension-free vaginal tape.Editorial Comment: The paper challenges the concept that to be successful a TVT must be placed at the midurethra. Recent reports tell us that even when thought to be placed at the midurethra, often a TVT is closer to the bladder neck, yet it remains successful. This contribution reports on a select group of patients who had the tension-free tape placed knowingly at the UVJ rather than the traditional midurethra location. Unfortunately, this case series provides the weakest type of medical evidence, and no serious conclusions can be drawn from it. It should lead to a prospective, randomized study of the two techniques with objective outcome reporting. Only then can a truly scientific conclusion be made.     

CONTINENCE MECHANISM OF THE ORTHOTOPIC NEOBLADDER: URODYNAMIC ANALYSIS OF ILEOCOLIC NEOBLADDER AND EXTERNAL URETHRAL SPHINCTER FUNCTIONS

Background: The main objectives of bladder substitution are the preservation of the upper urinary tract and maintenance of urinary continence. Orthotopic bladder substitution makes it possible to achieve urinary continence as well as normal passage of urine through the urethra. Creation of a low pressure reservoir and careful preservation of the distal sphincter mechanism are considered to be of utmost importance for the maintenance of urinary continence after orthotopic bladder Substitution. However, sphincter behavior after orthotopic bladder substitution has not been fully elucidated. The purpose of this study was to evaluate the vesicourethral continence mechanism after orthotopic bladder substitution in male patients. Methods: Urodynamic evaluation was performed in 14 male patients after cystoprostatectomy for bladder cancer and an ileocolic neobladder using a cecourethral anastomosis. Results: Good continence was achieved in 86% (12/14) of the patients during the day and in 79% (11/14) at night. On cystometry, maximum capacity of the neobladders was 434 ± 21 ml (mean ± SEM), and basal pressure at maximum capacity was 15.6 ± 0.9 cm water. Phasic neobladder contraction with amplitudes ranging from 14 to 40 (26.6 ± 2.7) cm water were noted in 11 of 14 patients. Sphincter electromyography demonstrated an increase in the frequency of action potentials of the external urethral sphincter during neobladder filling from empty to 80% of capacity (from 8.9 ± 1.6 to 14.6 ± 2.1 spikes per second; mean percentage increase, 64%, in patients with daytime continence). Maximum urethral closure pressure on urethral pressure profile was 49.9 ± 3.5 (range, 30 to 64) cm water in patients with daytime continence, while in two patients who were incontinent during the day and at night maximum urethral closure pressure was lower (16 and 24 cm water) and the recruitment of action potentials of the external urethral sphincter during neobladder filling was impaired (percentage increase, 15% and 20%). Conclusions: An ileocolic neobladder has characteristics of a low pressure reservoir with a satisfactory continence rate. The vesicourethral continence reflex is well preserved in patients with continence after orthotopic bladder Substitution.     

腹腔镜前列腺癌根治术术中实时盆底括约肌肌电监测的可行性研究

目的 通过在腹腔镜前列腺癌根治术中实时用NIM-ResponseTM肌电监测仪监测盆底括约肌电活动,了解控尿神经的分布,以便术中保护控尿神经,提高术后控尿效果;并对比手术前后患者控尿情况,评价实时监测技术在保护控尿神经方面的效果及意义.方法 80例前列腺癌患者临床分期为T2a~T3a纳入研究.将这些术前控尿正常的患者随机分成2组,每组40例.其中A组(神经监测组)利用NIM-ResponseTM肌电监测仪对以上患者腹腔镜前列腺癌根治术中盆底括约肌电活动进行术中实时监测.所有患者均采用气管全麻,避免术中使用肌松药.接地电极接于上臂,探测电极置于肛门括约肌及尿道括约肌.术中在前列腺邻近结构处以神经刺激探针以最高5 mA电流刺激和探测证实控尿神经在膀胱颈、前列腺、尿道周围行程及功能状态,通过避免电切电凝破坏控尿神经邻近结构达到保护其免受损伤的目的.B组(非神经监测组)行常规腹腔镜前列腺癌根治术.对比术前、术后拔尿管后24 h、术后3个月和术后6个月患者控尿情况,包括尿动力学检查、尿垫试验、膀胱镜检查.结果 术后两组拔尿管后24 h完全控尿率有显著差异(65.0%vs 37.5%,P<0.05)、术后3个月和术后6个月控尿率则无差异(80.0%vs 75.0%,P>0.05和92.5%vs 90.0%,P>0.05).术后30 d尿动力学检查证实80例患者前列腺部尿道控制带阻力消失,尿道闭合压正常存在,括约肌肌电正常存在.膀胱镜见40例患者尿道括约肌结构存在,镜下括约肌收缩功能良好.结论 腹腔镜前列腺癌根治术中采用盆底括约肌电活动实时监测,对控尿神经的解剖及功能分布有较强的准确性,可加快术后控尿功能恢复.     

The outcome of bladder neck closure in children with severe urinary incontinence

PURPOSE: We evaluated the outcome of children who underwent bladder neck closure for the management of severe urinary incontinence. MATERIALS AND METHODS: Bladder neck closure was performed in 12 patients with bladder exstrophy, 4 with myelomeningocele and 4 with urogenital sinus anomalies for severe urinary incontinence that persisted after multiple failed bladder outlet procedures. The effectiveness of bladder neck closure and the need for subsequent surgeries were ascertained. RESULTS: Mean followup was 5.4 years (range 1 to 12). At 3 months after surgery 40% of the patients were completely dry, 20% had leakage via the stoma and 40% had a urethral fistula. After additional surgeries 85% of the patients were completely continent 2 years following bladder neck closure (15% declined further surgeries or had an ileal conduit). Of the 15 patients with followup longer than 3 years only 40% remained completely dry, and leakage via the stoma developed in 47% after being dry for 1 year. Repeat urodynamic studies did not show any adverse changes in bladder dynamics in the incontinent patients. Stomal stenosis occurred in 30% of the patients and bladder stones developed in 40%. None of the patients had hydronephrosis or bladder perforation. The early complication of fistula formation and the late development of leakage via the stoma appear to be related in part to compliance with intermittent catheterization. CONCLUSIONS: Bladder neck closure is an effective method of achieving urinary continence in children in whom other bladder outlet surgery has failed. However, its success is dependent in part upon compliance with intermittent catheterization. Finally children who have undergone bladder neck closure are at an increased risk for stomal stenosis and bladder stones.     

Effect of radical prostatectomy on sensory threshold and pressure transmission

PURPOSE: The mechanisms involved in post-radical prostatectomy incontinence remain unclear despite previous anatomical and functional studies. In addition, the factors responsible for the restoration of continence are not well studied. To improve our understanding of the alterations in continence mechanisms, we prospectively investigated the temporal changes in urodynamic parameters after radical prostatectomy. MATERIALS AND METHODS: Cystometry, urethral pressure profilometry and posterior urethral sensory threshold measurements were performed in patients undergoing radical prostatectomy. Preoperative pressure transmission was determined by the maximal urethral pressure divided by the maximal abdominal pressure during cough maneuvers at a bladder volume of 200 ml. Postoperative sensory threshold, pressure transmission (% of pressure transmission), maximal urethral closure pressure and functional sphincter length were measured 6 weeks and 6 months after prostatectomy. These parameters were compared between continent and incontinent patients. RESULTS: Preoperative and postoperative urodynamic studies were completed in 34 patients. The continence rate after 6 weeks was 18% (6 patients) and improved to 82% (28) after 6 months. Preoperatively sensory threshold was 16 +/- 11 mA. After 6 weeks and 6 months, respectively, sensory threshold was significantly higher in incontinent (84 +/- 11 mA., 70 +/- 8 mA.) compared to continent (65 +/- 8 mA., 41 +/- 12 mA.) patients. Preoperative proximal urethral sensory threshold was not correlated with degree of postoperative incontinence determined by pad tests. Pressure transmission was not different in continent and incontinent patients postoperatively. After 6 weeks and 6 months, respectively, pressure transmission was 77% and 91% in continent, and 37% and 58% in incontinent patients (p = 0.04, p = 0.03). Maximal urethral closure pressure was significantly higher in continent patients (35 +/- 6 cm. H2O) compared to incontinent patients (11 +/- 9 cm. H2O). Sphincter length decreased from 50 mm. preoperatively to 24 mm. after 6 weeks and 25 mm. after 6 months. There was no difference in sphincter length between continent and incontinent patients. CONCLUSIONS: Posterior urethral sensitivity and pressure transmission are impaired immediately after prostatectomy. An improvement in these parameters after 6 months is associated with the restoration of continence. These observations suggest that urinary continence after radical prostatectomy depends on the integrity of posterior urethral sensation and the efficiency of pressure transmission.     

The significance of the open bladder neck associated with pelvic fracture urethral distraction defects.

PURPOSE: As a result of pelvic fracture urethral distraction defects, urinary continence relies predominantly on intact bladder neck function. Hence, when cystoscopy and/or cystography reveals an open bladder neck before urethroplasty, the probability of postoperative urinary incontinence may be significant. Unresolved issues are the necessity, the timing and the type of bladder neck repair. We report the outcome of various therapeutic options in patients with pelvic fracture urethral distraction defects and open bladder neck. We also attempt to identify prognostic factors of incontinence before urethroplasty. MATERIALS AND METHODS: We retrospectively reviewed the records of 15 patients with a mean age of 30 years in whom an open bladder neck was identified before posterior urethroplasty between January 1981 and October 1997. RESULTS: Of the 15 patients 6 were continent and 8 were incontinent postoperatively. One patient underwent artificial urethral sphincter implantation simultaneously with pelvic fracture urethral distraction defect repair and was dry postoperatively without sphincter activation. Average bladder neck and prostatic urethral opening on the cystourethrogram before urethroplasty was significantly longer in incontinent (1.68 cm.) than in continent (0.9 cm.) patients. Of the 8 patients who were incontinent 6 underwent bladder neck reconstruction, 1 artificial urinary sphincter and 1 periurethral collagen implant. Five patients with bladder neck reconstruction are totally continent and 1 requires 1 pad daily. The patient who underwent collagen implant requires 2 pads daily and the patient who received an artificial urethral sphincter has minor urge leakage. CONCLUSIONS: Open bladder neck before urethroplasty may herald postoperative incontinence which may be predicted by radiographic and cystoscopic features. Evaluation of the risk of postoperative incontinence may be valuable, and eventually guide the necessity and timing of anti-incontinence surgery, although our preference remains to manage the pelvic fracture urethral distraction defects and bladder neck problem sequentially. Bladder neck reconstruction provides good postoperative continence rates and is our technique of choice.     

Surgical management of incontinence in bladder exstrophy.

Between 1978 and 1990, 86 patients with previously closed classical bladder exstrophy and 10 patients seeking undiversion have presented for continence management and have undergone selective reconstruction designed for voiding and/or intermittent urethral catheterisation. The reconstruction in these 96 patients has been reviewed. Eight of the 10 patients undergoing undiversion achieved a satisfactory state of continence but 4 required Mitrofanoff procedures to enable catheterisation. Of the other 86 patients, 2 reached a satisfactory state of continence without further surgery; 79 underwent bladder neck surgery for continence either without augmentation (n = 32) or with augmentation (n = 47). Twenty of the 32 patients who were treated by bladder neck reconstruction alone were later found to require augmentation. Five patients had very early augmentation either to facilitate neonatal closure or on account of severe upper tract dilatation. Of these, 1 became continent without further surgery and 4 demonstrated the need for bladder neck reconstruction. Thus 12 children achieved successful continence (n = 6) or are evolving satisfactorily with potential success (n = 6) as a result of bladder neck reconstruction. Of the 71 patients requiring bladder neck reconstruction and augmentation, 68 have completed their surgery. The current status of these patients is: satisfactory in 57 (80%) (42 void/urethral clean intermittent catheterisation (CIC), 7 waiting to learn CIC, 5 Mitrofanoff, 3 artificial urinary sphincter (AUS]. Of the remaining 11 patients (20%), 8 are unsatisfactory to varying degrees and the status of the other 3 is unknown.     

Urodynamic and ultrasound characteristics of incontinence after radical hysterectomy

AIMS: To test whether symptoms of urinary incontinence after radical hysterectomy could be objectified with urodynamics and ultrasound. METHODS: This case-control study comprised 100 women who underwent radical hysterectomy for cervical cancer without post-operative radiotherapy. Fifty women reporting urinary incontinence were matched with 50 women reporting continence. All women were assessed with ultrasound of the bladder neck movements and urodynamics. RESULTS: No differences were found in ultrasound or urodynamic findings regarding mobility of the bladder neck, maximal detrusor pressure, post-voiding residual urine, flow of urine, or bladder capacity. A significant reduction in urethral pressure at rest and at contraction among the incontinent women was, however, demonstrated. Among urge-incontinent women, urethral pressure at rest was significantly lower than among continent and stress-incontinent women, respectively. Stress-incontinent women had significantly lower urethral pressure at contraction than did urge-incontinent and continent women. CONCLUSIONS: No differences in urodynamic or ultrasound findings were observed between the two groups, except for an overall difference in the intraurethral pressure. A decrease in the urethral pressure could contribute to the characterization of incontinence after radical hysterectomy, indicating that the urethral sphincter mechanism plays a role in the pathophysiology. In this study design, the mobility of the bladder neck did not play any role.     

Orthotopic bladder substitution in men revisited: identification of continence predictors

PURPOSE: We determined the impact of the functional characteristics of the neobladder and urethral sphincter on continence results, and determined the most significant predictors of continence. MATERIALS AND METHODS: A total of 88 male patients 29 to 70 years old underwent orthotopic bladder substitution with tubularized ileocecal segment (40) and detubularized sigmoid (25) or ileum (23). Uroflowmetry, cystometry and urethral pressure profilometry were performed at 13 to 36 months (mean 19) postoperatively. The correlation between urinary continence and 28 urodynamic variables was assessed. Parameters that correlated significantly with continence were entered into a multivariate analysis using a logistic regression model to determine the most significant predictors of continence. RESULTS: Maximum urethral closure pressure was the only parameter that showed a statistically significant correlation with diurnal continence. Nocturnal continence had not only a statistically significant positive correlation with maximum urethral closure pressure, but also statistically significant negative correlations with maximum contraction amplitude, and baseline pressure at mid and maximum capacity. Three of these 4 parameters, including maximum urethral closure pressure, maximum contraction amplitude and baseline pressure at mid capacity, proved to be significant predictors of continence on multivariate analysis. CONCLUSIONS: While daytime continence is determined by maximum urethral closure pressure, during the night it is the net result of 2 forces that have about equal influence but in opposite directions, that is maximum urethral closure pressure vs maximum contraction amplitude plus baseline pressure at mid capacity. Two equations were derived from the logistic regression model to predict the probability of continence after orthotopic bladder substitution, including Z1 (diurnal) = 0.605 + 0.0085 maximum urethral closure pressure and Z2 (nocturnal) = 0.841 + 0.01 [maximum urethral closure pressure - (maximum contraction amplitude + baseline pressure at mid capacity)].     

Assessment of the intrinsic urethral sphincter component function in postprostatectomy urinary incontinence

Postprostatectomy incontinence remains a disabling condition. Sphincter injury, detrusor instability, and decreased bladder compliance have been previously reported as major factors. The aim of this study was to evaluate the urethral sphincter intrinsic component, which may provide passive continence. A urodynamic evaluation was performed in 20 patients undergoing a radical retropubic prostatectomy in the preoperative period and 3 months after surgery. Patients with disabled urinary incontinence underwent a new urodynamic evaluation 6 months later. The urethral pressure profile was measured just before, then 10, 20, and 30 minutes after the injection of 0.5 mg/kg moxisylyte chlorhydrate, an alpha adrenergic blocker. Three different pressure components were defined in urethral sphincter capacity: baseline, adrenergic, and voluntary. A postoperative intrinsic urethral sphincter pressure component was found in 17 patients and its value was under 6 cm H(2)O in five cases of severe incontinence. No significant difference was observed for these patients on urethral profile components 6 months later. In contrast, in cases of significant intrinsic component value, no incontinence was observed in most patients. Passive continence after radical prostatectomy should be a matter of concern and may also explain paradoxical incontinence, despite high voluntary urethral pressure obtained after reeducation. A follow-up evaluation of the intrinsic sphincter component is suggested, by using an alpha receptor blockage test during urodynamic studies in the management of patients with postprostatectomy incontinence.     

Transvaginal ultrasonography and urodynamic evaluation after suspension operations: comparison among the Gittes, Stamey and Burch suspensions

Radiological and ultrasonographic imaging enables the objective determination of bladder neck position and movement in stress urinary incontinence. Postoperative results were evaluated in 60 patients after Burch colposuspension (29) or bladder neck suspension according to the Gittes (18) or Stamey (13) method. No differences in continence rates were noted 3 months postoperatively (Gittes 83%, Stamey 85% and Burch 93% of the patients). Late results were assessed by urodynamic evaluation and transvaginal ultrasonography. The largest decrease in continence rate was observed after the Gittes procedure (44% of the patients continent, mean followup 14.7 months), in comparison with the Stamey (69% continent after 34.6 months) and Burch (86% continent after 30.5 months) procedures. Urodynamic parameters showed no significant differences for the 3 groups. Transvaginal ultrasonography did not indicate a correlation between absolute resting or stress position of the bladder neck and continence. The main factor concerning continence was the rotation angle and descent of the bladder neck during stress. Our data indicate that transvaginal ultrasonography is a safe and reliable method to evaluate the postoperative outcome for stress urinary incontinence.