Stress incontinence surgery for patients presenting with mixed incontinence and a normal cystometrogram


  • T. Osman

    Corresponding author
    1. Urology Department, Ain Shams University, Cairo, Egypt
      T. Osman, Urology Department, Ain Shams University, Cairo, Egypt.
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T. Osman, Urology Department, Ain Shams University, Cairo, Egypt.



To evaluate the outcome of surgery for stress urinary incontinence (SUI) in patients presenting with a combination of stress and sensory urge UI.


The study comprised 75 women presenting with mixed incontinence; the most important inclusion criterion was a negative cystometrogram for detrusor overactivity. Based on random selection, a third of the patients received a 6-month course of anticholinergic treatment (group 1) and 50 (group 2) had surgery for SUI. The surgical procedure depended on the Valsalva leak-point pressure (VLPP); those with a VLPP of ≥ 90 cmH2O underwent Burch retropubic bladder neck suspension (group 2a, 24 patients) while 26 (group 2b) with a VLPP of < 90 cmH2O had pubovaginal sling (PVS) surgery. A further group of 20 patients with pure SUI (no urge UI) underwent surgery (PVS in 12 and Burch in eight) as a control group (group 3). After at least 6 months of follow-up (mean 9.3, sd 1.7), 68 patients were evaluable; they were assessed subjectively and objectively for dryness, and by a urodynamic evaluation and quantitative assessment using the SEAPI scoring system.


In group 1 none of the patients became completely dry; there was persistent stress with and without urge UI in nine (43%) and 12 (57%) of the available 21 patients, respectively. Only three of those who had persistent SUI with no urge in the whole study group were satisfied and chose to continue anticholinergic therapy despite SUI. In this group the mean (sd) improvement in the subjective and objective SEAPI score was 3.4 (1.0) and 2.3 (3.8), respectively. In group 2a, 20 of the available 23 patients (87%) became completely dry (both stress and urge continent). The mean improvement in the SEAPI scores was 7.8 (0.9) and 7.8 (1.3), respectively. In group 2b, 20 of the 24 patients (83%) became completely dry, with mean improvements in SEAPI scores of 8.2 (0.4) and 7.9 (0.3), respectively. The improvement was statistically significant after surgery, vs anticholinergic therapy, for all variables (P < 0.05). The incidence of persistent urge UI was highest in group 1 (43%), being 13% in group 2 (13% and 12% in 2a and b, respectively). In group 3 there was de novo urge UI in four of the 20 patients, and not significantly different from that in group 2.


Most patients with mixed stress and urge UI and a normal cystometrogram were cured of both symptoms by surgery. The incidence of residual urge in such patients was no higher than that of de novo urge after surgery in patients with genuine SUI.


(stress) urinary incontinence


(idiopathic) detrusor overactivity


(Valsalva) leak-point pressure


pubovaginal sling.


Stress urinary incontinence (SUI) is defined by the International Continence Society as a condition of urinary leakage through the urethra driven by abdominal pressure with no evidence of a detrusor pressure component [1]. However, only 25% of incontinent women actually present with pure SUI, while most (55%) present with a combination of stress and urge UI, i.e. mixed UI [2]. Although it is established that the most effective treatment for genuine SUI is surgery, managing those presenting with mixed UI is less clear. However, despite some older reports, several studies showed that many patients are cured of both components after surgery [3–7]. Most of these studies were retrospective and many included patients presenting with stress combined with different forms of idiopathic detrusor overactivity (IDO), i.e. high- and low-amplitude DO, and DO with a negative cystometrogram (previously termed sensory detrusor instability). Compared with urge presenting with urodynamic evidence of DO, urgency with a normal cystometrogram is ill-defined, particularly in the presence of SUI. The present prospective study focused on managing mixed UI associated with a normal cystometrogram, and comprised a randomized comparison between anticholinergic therapy and surgery for such patients. Furthermore, the same surgical techniques were used in a group of patients with genuine SUI as a control, mainly to assess the incidence of de novo urge UI and compare it with the incidence of persistent urge after surgery in the main study group with mixed UI.


From September 1998 to February 2002 all women presenting with mixed UI (a combination of stress and urge UI) were assessed by a history, clinical examination (general, abdominal and vaginal), routine laboratory tests, a lateral cystogram, abdominopelvic ultrasonography with an estimate of the postvoid residual urine volume, a water cystometrogram with an estimate of the Valsalva leak-point pressure (VLPP) and uroflowmetry. For the multichannel cystometrogram a double 10 F catheter was used for filling and intravesical pressure monitoring, and a rectal catheter for intra-abdominal pressure recording. For the filling cystometrogram water was instilled at a physiological (slow) filling rate (≤ 10 mL/min). Starting at 200 mL bladder capacity the patient was instructed to perform a Valsalva manoeuvre until there was leakage, and if not the test was repeated at 50 mL increments. The LPP was recorded and the cystometrogram completed up to the maximum cystometric capacity; the uroflow was measured afterwards.

Patients were selected using the following criteria: (i) a combination of stress and urge UI for > 6 months; (ii) no treatment for UI for ≥ 3 months; (iii) sterile urine culture; (iv) a cystometrogram negative for motor DO (i.e. no uninhibited detrusor contractions and no detrusor pressure rise of > 5 cmH2O); (v) unobstructed uroflow; (vi) no previous surgery for incontinence; (vii) no suspicion of other pathology, particularly carcinoma in situ and interstitial cystitis. In all, 75 patients were selected (mean age 49.8 years, sd 9.7, range 35–61).

Based on a random selection, using the block-randomization technique, 25 patients received anticholinergic treatment for ≥ 6 months (group 1) and 50 had surgery (group 2), selected according to the VLPP. Those with a VLPP of ≥ 90 cmH2O had a Burch retropubic suspension (group 2a, 24 patients) and those with a lower VLPP had pubovaginal sling (PVS) surgery (group 2b, 26 patients). As a control group (group 3), 20 patients with pure SUI (no urge component) had surgery, also selected according to the VLPP (PVS in 12 and Burch in eight).

Anticholinergic treatment was administered to patients as oxybutynin hydrochloride 5 mg three times daily with the dose gradually increased until there was a maximum response or the appearance of undesirable side-effects, i.e. significant atropine-like manifestations. The treatment was continued for 6 months at the maximum therapeutic dose.

Bladder neck suspension in group 2a followed the Burch principle [8], i.e. suspending the vaginal wall and the periurethral tissue toward the iliopectineal line of Cooper, with simple elevation of the vaginal wall and periurethral fascia to about mid-way between the original position of the bladder neck and the Cooper ligament.

The PVS in group 2b was as reported by McGuire and Lytton [9] but with minimal tension applied to the sling so that there was little leakage with cough or suprapubic pressure while the patient was under spinal or general anaesthesia, respectively. The same surgical principles were followed in group 3; all surgical procedures were carried out by the author.

For group 1, the patients were followed monthly and only those complying and who completed 6 months of treatment were included in the study. The treatment outcome in this group was evaluated while the patient was under treatment, i.e. during the seventh month, whereas groups 2 and 3 were evaluated 6 months after surgery. The evaluation was both subjective and objective. The former comprised a history, the patients being categorized as either completely dry, having only residual urge UI, only residual SUI, or both, and they also completed a quantitative symptom scoring system, the SEAPI [10] (Appendix).

The objective evaluation comprised: (i) a vaginal examination while the patient had a comfortably full bladder sensation, to detect stress-induced leakage, both in the lithotomy position and while upright; (ii) a lateral cystogram; (iii) a filling cystometrogram with VLPP testing; (iv) uroflowmetry; and (v) quantitative scoring of the findings of clinical, radiological and urodynamic examination, using the objective SEAPI scoring system [10].

The results were compared with the values before treatment and evaluated using the chi-squared test for qualitative data (e.g. dryness rate) and anova with the post-hoc test to detect the least significant difference for the quantitative data (e.g. the SEAPI score results)


After ≥ 6 months of follow-up (mean 9.3, sd 1.7, range 6–12) 68 patients were evaluable; the results are shown in Table 1. In group 1, none of the patients became completely dry. Only three of those who had persistent SUI with no urge were satisfied and chose to continue on anticholinergic therapy, despite SUI. The remaining 18 patients were dissatisfied and considered surgery. The subjective and objective SEAPI scores improved (Table 1). In group 2a and 2b the subjective and objective SEAPI scores also improved; for group 2 as a whole the general success rate was similar between the Burch and PVS groups, with no statistically significant differences (P > 0.05).

Table 1.  The outcome after treatment and the mean SEAPI scores
12a2b2 (all)3
  • *

    P < 0.05 group 1 vs 2a, and vs 2b;

  • †1 vs 2a and vs 2b.

No. evaluable2123244720
n (%):
Completely dry 020 (87)20 (83)40 (85)16 (80)
Only urge 0 2 (9) 2 (8) 4 (8.5) 4 (20)
Only SUI12 (57) 0 1 (4) 1 (2) 0
Both urge and SUI 9 (43) 1 (4) 1 (4) 2 (4) 0
Mean (sd) SEAPI scores
Before 9.53 (1.06)10.63 (1.25) 11.27 (1.10)  
After 6.13 (0.09) 2.83 (1.62) 3.17 (1.5)  
Improvement* 3.4 (0.95) 7.8 (0.85) 8.17 (0.38)  
Before 8.38 (1.19)10.07 (1.33)10.74 (1.03)  
After 6.08 (1.19) 2.28 (1.47) 2.74 (1.34)  
Improvement 2.3 (3.57) 7.79 (1.33) 7.931 (0.32)  

The urodynamic evaluation of the six patients who persistently complained of urge after surgery showed that five had low-amplitude DO (uninhibited detrusor contraction of < 15 cmH2O) while only one had a normal cystometrogram as before. The uroflowmetry showed a significant decrease in the maximum flow in those who persistently complained of urge UI; the mean (sd, range) initial flow was 25.6 (3.03, 19–31.5) mL/s and the final flow 16.4 (4.2, 12.2–21.7) mL/s (P < 0.05). The maximum flow in patients who were cured of both SUI and urge UI did not decrease significantly, with values of 23.5 (5.2, 18–33.6) and 20.35 (6.8, 14.2–24.7) mL/s, respectively. This suggests that residual urgency after surgery may be caused by iatrogenic relative obstruction. In group 3 (SUI with no urgency or urge) after surgery 16 patients were completely dry while four had de novo urge UI but none had persistent SUI. De novo urge UI was associated with low-amplitude DO in all four patients.


The cause of urge in a patient with SUI is unknown; urge episodes coincide with an uninhibited detrusor contraction (motor instability) in some patients, while up to half have a normal cystometrogram, a phenomenon formerly termed sensory detrusor instability [11–16]. IDO in patients with outlet deficiency and SUI has been proposed in two different studies to be a result of a reflex stimulated by urine leakage into the urethra [17,18]. The absence of any urodynamic proof of DO may be a result of an inhibitory effect of the patient during the course of a urodynamic study, while during activities of normal living the unstable contractions are unmasked and manifest with symptoms [19]. Klein [20] suggested that sensory urge is a dysfunction of mucosal sensors that normally warn the patient on bladder filling. Ambulatory urodynamic monitoring has been used to evaluate such patients and can detect a higher incidence of motor DO in such patients than can conventional cystometrography [21].

The urgency-urge UI complex in many patients with SUI is probably a false interpretation of impending stress-induced leakage, i.e. ‘Once a first desire or normal desire is perceived by the patient, she rushes to the toilet to protect herself from a stress incontinence event’. This results in a learned reflex that the patient develops and reinforces over time. On questioning, these patients may report a symptom mimicking urgency or urge UI, but with careful interrogation many of them have only a severe form of SUI. Consequently these patients can be seen as having SUI with ‘pseudo urgency syndrome’.

Regardless of the pathogenesis, the treatment of patients with mixed urge and SUI involves two main approaches, i.e. anticholinergic therapy and surgery. The former has been associated with significant resolution of the urge component in only two-thirds of these patients [22,23], but patients are not expected to be completely dry with this treatment alone, as treatment of the outlet defect was not targeted. In the present author's experience most of these patients are not satisfied with the anticholinergic therapy alone because of one or more of a poor response, side-effects, the cost and/or the need for continuous treatment. However, the results of surgery in the same category of patients, in contrast to earlier reports, continue to be satisfactory. A clinical and urodynamic evaluation shows that generally the resolution rate of urge in patients with mixed SUI and urge who have surgery is 50–70%[3–7,14,24–26].

The present study was designed to prospectively compare the results of anticholinergic therapy and surgery in such patients who had a negative cystometrogram. A comprehensive evaluation was used, including the SEAPI scoring system to evaluate the patients quantitatively. This system is particularly useful in these patients as it includes questions about the urge episodes and the detrusor pressure.

Anticholinergic therapy, as expected, completely cured none of the patients; 43% reported persistent SUI and urge, and 57% persistent SUI. However, three patients, although having persistent SUI, were satisfied with continuous anticholinergic therapy. Surgery was used in two-thirds of the present patients, selected according to the VLPP; those with a VLPP of ≥ 90 cmH2O probably had an anatomical defect, thus indicating a suspension procedure (group 2a), while those with a VLPP of < 90 cmH2O had a sphincteric defect and required a PVS (group 2b).

After surgery, 85% of the patients became completely dry (87% in group 2a and 83% in 2b); only 13% had residual urge UI after a Burch and 12% after a PVS operation, with the subjective and objective SEAPI scores improving after both. In general, the results of both procedures were similar and there was no statistically significant difference in the success rates between these groups (P > 0.05). However, the results of surgery were significantly better than those of anticholinergic treatment for all variables evaluated (P < 0.05).

The present results are similar to those reported by others in managing mixed UI, but are better than those in other studies of managing SUI and sensory urge using sling urethropexy, e.g. [24]. The authors reported 39% with complete resolution of urge and the best success rate (91%) was after a PVS in patients with SUI and low-amplitude DO. In a similar group to the present patients, Brown and Hilton [21] reported that only 37% had resolution of urge after retropubic suspension, compared to 87% in the present series after a Burch procedure.

The urodynamic evaluation provided two important points. First, there was a significant relation between outlet obstruction and postoperative urgency. Those patients with residual urgency (in contrast to the others) had a significant decrease in their flow rates. This contrasts with the findings of Fulford et al.[25], who reported persistent urge in 31% of their patients, attributed to a failure to achieve bladder neck closure at rest. Second, although all the present patients had a normal cystometrogram initially, nine of the 10 who had residual or de novo urge UI had DO incontinence. This suggests that the pathogenesis of urgency before surgery differs from the residual or de novo urgency afterwards.

De novo urge UI occurred in 20% of the control group, statistically not significantly different from residual urge after surgery (13%) (P > 0.05); considering that the same surgery was used in all patients by the same surgeon, then a patient with mixed SUI and urge has no greater chance than a patient with genuine SUI to have urge UI after surgery. Persistent and de novo urge UI might be related to outlet obstruction created by surgery rather than the existence of this symptom beforehand. Consequently, operatively induced outlet obstruction should be avoided during surgery.

In conclusion, patients with mixed UI are likely to be cured of both the urge and stress components by surgery, although a few patients may remain with urge UI. The form of urge before and after surgery (persistent) in any patient is not necessarily the same, and it is not yet clear how to predict who will remain free of urge after surgery. However, avoiding outlet obstruction may protect many of these patients from the distressing urge after the procedure. The incidence of residual urge UI after surgery in patients with mixed UI was no higher than that of de novo urge UI after surgery in patients with genuine SUI.


The SEAPI Scoring System [10].

Subjective SEAPI Score

Stress-related leakage

0 = No urine loss

1 = Loss with strenuous activity

2 = Loss with moderate activity

3 = Loss with minimal activity or gravitational incontinence

Emptying ability

0 = No obstructive symptoms

1 = Minimal symptoms

2 = Significant symptoms

3 = Voiding in dribbles or urinary retention


0 = No descent

1 = Descent not to the introitus with strain

2 = Descent to the introitus with strain

3 = Descent through the introitus with strain


1 = Never used

2 = Used only for certain occasions

3 = Used daily for occasional accidents

3 = Used continuously for frequent accidents or constant leakage


0 = No urgency incontinence

1 = Rare urgency incontinence

2 = Urgency incontinence once a week

3 = Urgency incontinence at least once a day

Objective SEAPI Score

Stress-related leakage

Observe for leak during Valsalva

0 = No leak

1 = Leak at > 80 cmH2O

2 = Leak at 30–80 cmH2O

3 = Leak < 30 cmH2O

Emptying ability

Postvoid residual urine should be verified by repeated measurements

0 = 0–60 mL

1 = 61–100 mL

2 = 101–200 mL

3 = > 200 mL or unable to void


Position of the bladder neck relative to the symphysis pubis during cough or Valsalva as seen on lateral cystogram

0 = Above symphysis with strain

1 = < 2 cm below symphysis with strain

2 = > 2 cm below symphysis with strain

3 = > 2 cm below symphysis at rest


1 = Never used

2 = Used only for certain occasions

3 = Used daily for occasional accidents

3 = Used continuously for frequent accidents or constant leakage


0 = No pressure rise

1 = Rise late in filling (> 500 mL)

2 = Medium fill rise (150–500 mL)

3 = Early rise (< 150 mL)