Detrusor contractility in post-menopausal women: Impact of ageing, complaint and urodynamic diagnosis

INTRODUCTION

Detrusor contractility (DC) can have a considerable impact on the management oflower urinary tract symptoms (LUTS). However, it is currently impossible to predict, based on clinical data alone, which woman has an impaired DC. Our aim was to determine if DC, assessed by projected isovolumetric pressure-1 (PIP1) and VBN contractility parameter k, was associated with age, main complaint, and urodynamic diagnosis in a population of older women.

METHODS

Pressure-flow studies of non-neurologic post menopausal women over 65 referred for investigation of LUTS were retrospectively analyzed. Associations between DC indices PIP1 and k, and age, main complaint and urodynamic diagnosis were assessed in univariate analysis.

RESULTS

One hundred and ninety women were included (mean age 74.5 years). There was no significant association between detrusor contractility indices and age considered as a continuous or a categorical variable. Urge urinary incontinence was significantly associated with greater detrusor contractility regardless of age. Regarding urodynamic diagnoses, DC was greater when bladder outlet obstruction and detrusor overactivity were diagnoses vs. detrusor underactivity alone or associated with detrusor overactivity, regardless of age.

CONCLUSION

PIP1 and k indices allow an easy evaluation of detrusor contractility. In that population of older, post menopausal women, no significant change in the value of the indices is observed with aging whatever the complaint or the urodynamic diagnosis. None of these indices has predominance.

LEVEL OF EVIDENCE

4.

Urethral Closure Pressure at Stress: A Predictive Measure for the Diagnosis and Severity of Urinary Incontinence in Women

Purpose

Maintaining urinary continence at stress requires a competent urethral sphincter and good suburethral support. Sphincter competence is estimated by measuring the maximal urethral closure pressure at rest. We aimed to study the value of a new urodynamic measure, the urethral closure pressure at stress (s-UCP), in the diagnosis and severity of female stress urinary incontinence (SUI).

Methods

A total of 400 women without neurological disorders were included in this observational study. SUI was diagnosed using the International Continence Society definition, and severity was assessed using a validated French questionnaire, the Mesure du Handicap Urinaire. The perineal examination consisted of rating the strength of the levator ani muscle (0–5) and an assessment of bladder neck mobility using point Aa (cm). The urodynamic parameters were maximal urethral closure pressure at rest, s-UCP, Valsalva leak point pressure (cm H₂O), and pressure transmission ratio (%).

Results

Of the women, 358 (89.5%) were diagnosed with SUI. The risk of SUI significantly increased as s-UCP decreased (odds ratio [OR], 0.92; 95% confidence interval, 0.88–0.98). The discriminative value of the measure was good for the diagnosis of SUI (area under curve>0.80). s-UCP values less than or equal to 20 cm H₂O had a sensitivity of 73.1% and a specificity of 93.0% for predicting SUI. The association between s-UCP and SUI severity was also significant.

Conclusions

s-UCP is the most discriminative measure that has been identified for the diagnosis of SUI. It is strongly inversely correlated with the severity of SUI. It appears to be a specific SUI biomarker reflecting both urethral sphincter competence and urethral support.

Should maximal urethral closure pressure be performed before midurethral sling surgery for stress incontinence? A time to revisit

INTRODUCTION AND HYPOTHESIS

Maximum urethral closure pressure (MUCP) provides an objective assessment of urethral integrity, but its role in predicting outcome after midurethral sling (MUS) placement is debatable and current practice in the UK is variable. The study was carried out to determine if lower preoperative MUCP is associated with poor outcome following MUS.

METHOD

The study was a retrospective review of the British Society of Urogynaecology (BSUG) database and urodynamics (UDS) data. Patients who reported outcome as "no improvement", "worse" or "much worse" on the Patient Global Impression of Improvement (PGII) scale were identified as having a poor outcome. Patients who reported "a little improvement", "improved" and "very much improved" on the PGII were thought to have a good outcome. The preoperative demographics, UDS findings and quality of life (International Consultation of Incontinence questionnaires [ICIQ-SF]) data of the two groups were compared.

RESULT

A total of 236 women were identified for the study. Of these, 24 women (10.2 %) had a poor outcome. Of the remaining women reporting a good outcome, 50 cases were randomly selected. All urodynamic parameters, including mean functional urethral length (FUL), bladder capacity, and Qmax, were similar, except for mean MUCP 37.05 cm H2O, which was significantly lower in group 1 (poor outcome 37.05 cm H2O) compared with a mean MUCP of 50.6 cm H2O in group 2 (good outcome; p = 0.005).

CONCLUSION

We conclude that failure following MUS is associated with preoperatively lower MUCP, which can be used as a predictor of failure.

Detrusor after-contraction: a new insight

Aims:

Detrusor after-contractions (DAC) are non-common in adults. Both definition (nothing in ICS reports) and significance (artefact, link with detrusor overactivity (DO) or bladder outlet obstruction (BOO)) remain discussed. Our purpose was to carry out an analysis of the urodynamic parameters during voidings with DAC and, using the VBN model, to simulate pathophysiological conditions able to explain both voiding phase and DAC.

Materials and Methods:

From large urodynamic database of patients referred for evaluation of lower urinary tract dysfunction, DAC were observed in 60 patients (5.7%). Criteria for DAC were post-void residual <30mL and increase of detrusor pressure >10cmH₂O. VBN model was used for analysis of both pressure and flow curves, and simulations of pathophysiological conditions.

Results:

Onset of DAC (ODAC) occurred when Q=7.3±5.7mL/s and bladder volume=17.9±15.4mL. Urgency-frequency syndrome and urodynamic diagnosis of DO were the more frequent scenarios associated with DAC. ODAC was associated to an inversion of the slope of detrusor pressure curve without any perturbation in flow curve. Among tested pathophysiological hypothesis (great, abnormal, detrusor force, sphincter contraction), none allowed restoring all recorded curves (flow rate, voiding pressure and DAC).

Conclusion:

No urodynamic characteristic of the first part of voiding is an index of occurrence of DAC. ODAC is a significant phenomenon linked with the bladder collapse. DAC is not associated with BOO but more probably with DO and appears as the result of local conditions in an almost empty bladder (concentration of stresses around a transducer); thus DAC seems of weak clinical significance.

Urodynamics in a community-dwelling population of females 80 years or older. Which motive? Which diagnosis?

PURPOSE

To determine why community-dwelling women aged 80 years or over were referred for urodynamic evaluation despite their advanced age and which urodynamic diagnosis was made.

MATERIALS AND METHODS

One hundred consecutive females (80-93 years) were referred to our urodynamics outpatient clinic for evaluation of lower urinary tract symptoms (LUTS) between 2005 and 2008. Clinical evaluation comprised of a previous history of LUTS, previous medical history of neurological disease or dementia, pelvic floor dysfunction or prior pelvic surgery. Exclusion criteria were complete retention and severe dementia involving failure to understand simple instructions. Assessed items were results of uroflows (free flow and intubated flow), cystometry and urethral pressure profilometry, and final urodynamic diagnosis.

RESULTS

The main complaint evoked by the patients was incontinence (65.0%) of which 61.5% was "complicated" and urgency was reported by 70.0%. Interpretable free flow at arrival was very low (44.0%). Prevalence of detrusor overactivity was high, found in 45 patients of whom 16 had detrusor hyperactivity with impaired detrusor contractility. Detrusor overactivity and urgency were strongly associated (p = 0.004). Twenty-five patients had intrinsic sphincteric deficiency alone and 15 detrusor underactivity.

CONCLUSION

In this particular community-dwelling with an elderly female population, urodynamics is easily feasible. Incontinence, mainly "complicated" is the more frequent complaint and urgency the more frequent symptom. Urodynamic diagnosis underlines the high incidence of detrusor overactivity as well as impaired detrusor function.

Evaluation of the dynamic responses of female pelvic floor using a novel vaginal probe

The female pelvic floor (PF) provides anatomical support to many visceral organs, such as uterus, bladder, urethra, vagina, and rectum. Physiologically, the PF is made up of a number of highly coordinated muscle groups organized to respond to postural and abdominal stresses to maintain continence. In this article, we describe a new methodology for the evaluation of PF strength using a novel vaginal probe design, having force and displacement sensors. This design was derived on the basis of imaging data showing that force/displacement characteristics are important determinants of the integrity of the PF function. The prototype probe used was constructed to evaluate the dynamic responses to slow voluntary contractions as well as reflex stress contractions. Initial clinical experiments were performed on nine healthy female subjects. The probe recorded the force and displacement signals on the anterior and posterior sides of the subjects' middle vaginal wall in voluntary PF muscle contraction and cough. The time domain and frequency domain characteristics of the dynamic responses, including the force and displacement responses, of the vaginal wall were measured and the power and energy associated with the dynamic responses of the PF were analyzed showing the differences between the dynamic characteristics of the voluntary PF muscle contraction and cough. Results show that voluntary PF muscle contractions have higher amplitudes, longer duration, and higher power than reflex contractions. The design of this probe enables the measurement of force and displacement during rapidly occurring events.

Is urethral pressure profilometry a useful diagnostic test for stress urinary incontinence?

Urethral pressure profilometry is commonly used as a diagnostic test for stress urinary incontinence. The objective of this article is to review the published literature on urethral pressure profilometry to summarize its usefulness. MEDLINE was used to search the published English literature from 1966 to October 2000 for full-length original research articles on urethral pressure profilometry and stress urinary incontinence in women. Terms related to urethral pressure profilometry are defined consistently but techniques are not standardized, introducing variation in test results. Reproducibility of urethral pressure profilometry parameters is poor, both because of biological variation and variation within the test procedure itself (related in part to lack of standardization). Parameters of urethral pressure profilometry do not distinguish between continent and incontinent women and do not characterize the severity of incontinence or urethral incompetence. It is, therefore, concluded that urethral pressure profilometry is not a useful diagnostic test for stress urinary incontinence in women. Its use in clinical management is not supported by current evidence.

A computer model of the neural control of the lower urinary tract

Better understanding of the underlying working mechanism of the neural control of the lower urinary tract will facilitate the treatment of dysfunction with a neurogenic cause. We developed a computer model to study the effect of a neural control system on lower urinary tract behavior. To model the mechanical properties and neural control, assumptions had to be made. These assumptions were based, as much as possible, on knowledge and hypotheses taken from the literature. With valid assumptions, it should be possible to simulate normal as well as pathological behavior. To test the computer model, first, normal behavior of the lower urinary tract was simulated, and secondly, the known features of bladder outlet obstruction were simulated after the properties of the urethra were changed. The simulation results are comparable with measured data, so the assumptions on which the model is based could be valid. If the assumptions are valid, the feedback loops used in the model are also important feedback loops in vivo, and the model can be used to gain insight into the underlying mechanism of neural control.

Urogynecology and pelvic reconstructive surgery: office preoperative evaluation of the incontinent female

Successful research outcomes in the treatment of genuine stress incontinence depend upon correct preoperative urodynamic evaluation. These procedures and how they are used for diagnosis and the selection of the correct surgical procedure are discussed.