Advances in Ambulatory Urodynamics.

PURPOSE OF REVIEW: This manuscript reviews recent technological advances in ambulatory urodynamics. RECENT FINDINGS: Ambulatory urodynamics is currently recommended by the International Continence Society as a second-line diagnostic tool in patients with nondiagnostic traditional urodynamics. Novel techniques involving telemetric monitoring are in development, which utilize catheter-free wireless systems to address several recognized shortcomings of inoffice urodynamic studies. Current research in catheter-free bladder pressure measurements involves either an intravesical, intradetrusor, or transdetrusor approach. Real-time bladder volume estimation may be performed using ultrasonography, near-infrared spectroscopy, or bladder volume conductance measurement. Ambulatory urodynamics can measure bladder function in the "real world" setting, capturing physiological bladder filling and emptying and allowing patients to reproduce the activities that may trigger their symptoms. Telemetric devices being developed represent further advances in this field and focus upon improving diagnostic capabilities, evaluating patient response to treatment, and facilitating closed-loop bladder control with neuroprosthetic integration.

Optimization of activity-driven event detection for long-term ambulatory urodynamics.

Lower urinary tract dysfunction (LUTD) is a debilitating condition that affects millions of individuals worldwide, greatly diminishing their quality of life. The use of wireless, catheter-free implantable devices for long-term ambulatory bladder monitoring, combined with a single-sensor system capable of detecting various bladder events, has the potential to significantly enhance the diagnosis and treatment of LUTD. However, these systems produce large amounts of bladder data that may contain physiological noise in the pressure signals caused by motion artifacts and sudden movements, such as coughing or laughing, potentially leading to false positives during bladder event classification and inaccurate diagnosis/treatment. Integration of activity recognition (AR) can improve classification accuracy, provide context regarding patient activity, and detect motion artifacts by identifying contractions that may result from patient movement. This work investigates the utility of including data from inertial measurement units (IMUs) in the classification pipeline, and considers various digital signal processing (DSP) and machine learning (ML) techniques for optimization and activity classification. In a case study, we analyze simultaneous bladder pressure and IMU data collected from an ambulating female Yucatan minipig. We identified 10 important, yet relatively inexpensive to compute signal features, with which we achieve an average 91.5% activity classification accuracy. Moreover, when classified activities are included in the bladder event analysis pipeline, we observe an improvement in classification accuracy, from 81% to 89.0%. These results suggest that certain IMU features can improve bladder event classification accuracy with low computational overhead.Clinical Relevance: This work establishes that activity recognition may be used in conjunction with single-channel bladder event detection systems to distinguish between contractions and motion artifacts for reducing the incorrect classification of bladder events. This is relevant for emerging sensors that measure intravesical pressure alone or for data analysis of bladder pressure in ambulatory subjects that contain significant abdominal pressure artifacts.

The association of coital incontinence with clinical factors and single voiding cycle ambulatory urodynamic monitoring findings in women.

Introduction: Coital incontinence (CI) is a frequent problem in women with urinary incontinence (UI) with significant impact on female sexuality and quality of life. The underlying mechanism is controversial; it has been known that CI is associated with both stress urinary incontinence (SUI) and detrusor overactivity (DO). However, recently it has been reported that CI is mainly related with SUI and urethral incompetence, but not with DO. Ambulatory urodynamic monitoring (AUM) has been shown to be a sensitive tool for the detection of DO. The aim of this study was to investigate the clinical risk factors for CI and the association of CI with urodynamic diagnoses at single voiding cycle AUM. Methods: Records of sexually active women with urinary incontinence attending the urogynaecology unit of a university hospital, who completed the PISQ-12 were reviewed retrospectively (n = 1,005). Patients were grouped using the 6th question; patients answering "never" to this question were considered as continent during coitus (n = 591) and patients reporting any urinary leakage at coitus were considered to have CI (n = 414). Demographics, clinical examination findings, incontinence severity measured by the Sandvik Incontinence Severity Index, scores of Turkish validated questionnaires (PFDI-20, IIQ-7, OAB-V8, and PISQ-12) and single voiding cycle AUM findings were compared, and univariate and multivariate logistic regression analyses were performed. Results: Among all sexually active women with UI, 41.2% had CI; UI was more severe, symptom bother was higher, related quality of life (p < 0.001) and sexual function were worse (≤0.018) in these women. Younger age (OR 0.967, p < 0.001), history of vaginal delivery (OR 2.127, p = 0.019), smoking (OR 1.490, p = 0.041), postural UI (OR 2.012, p = 0.001), positive cough stress test (OR 2.193, p < 0.001), and positive SEST (OR 1.756, p = 0.01) were found as independent clinical factors associated with CI. Urodynamic SUI (OR 2.168, p = 0.001) and MUI (OR 1.874, p = 0.002) were found as significant and independent urodynamic diagnoses associated with CI, whereas no association was found with DO or UUI. Conclusion: Both clinical and AUM findings supported that CI is a more severe form of UI that it is mainly related with SUI and urethral incompetence, but not with UUI or DO.

A prediction model for detrusor overactivity at ambulatory urodynamics in women with urinary incontinence.

OBJECTIVE(S): To develop a multivariable model using both clinical examination findings and validated questionnaires' scores for predicting the presence of detrusor overactivity observed during ambulatory urodynamic monitoring in women with urinary incontinence. STUDY DESIGN: The study population was chosen from a registry of women evaluated with urodynamics for urinary incontinence retrospectively. Data for baseline characteristics, clinical findings, and ambulatory urodynamic records were evaluated for all women included to the study. Urodynamic data were obtained by retrospective review of urodynamic traces with a standardized protocol during single voiding cycle, compatible to the standards of International Continence Society (ICS) for ambulatory urodynamic monitoring. RESULTS: A total of 395 women with urinary incontinence were included in the study. Detrusor overactivity was diagnosed in 57.1% of women included to the study. Clinical factors positively associated with detrusor overactivity were higher body-mass index (OR = 1.10; 95% CI 1.03-1.15, p < 0.001), higher OAB-V8 (Overactive bladder awareness tool - version 8) scores (OR = 1.04; 95% CI 1.01-1.06, p < 0.001) and presence of urgency urinary incontinence (OR = 2.39; 95% CI 1.47-3.81, p < 0.001). The presence of postural urinary incontinence (OR = 0.51; 95%CI 0.28-0.90, p = 0.021) and insensible loss of urine (OR = 0.33; 95%CI 0.27-0.93, p = 0.005) had negative associations with detrusor overactivity in the final multivariate logistic regression analysis. CONCLUSION(S): BMI, OAB-V8 scores, urgency urinary incontinence, postural urinary incontinence and insensible loss of urine were associated with the presence of detrusor overactivity according to our prediction model. However, the overall model accuracy suggests urodynamic studies are still needed for a definitive diagnosis. Nevertheless, the prediction may be beneficial for selecting a subgroup of women who are unlikely to benefit from ambulatory urodynamic monitoring for the diagnosis of detrusor overactivity.

Ambulatory urodynamic monitoring of women with overactive bladder syndrome during single voiding cycle.

OBJECTIVE(S): To present data of standardized ambulatory urodynamic monitoring (AUM) performed in women with overactive bladder syndrome (OAB) and to evaluate the relevance of AUM data with clinical findings of the patients. STUDY DESIGN: Records of women with symptoms of OAB were retrospectively reviewed (n=249). Of women fulfilling the Overactive Bladder Awareness Tool (OAB-V8) with a score ≥8 and the 3-day voiding diary (VD) with a frequency >7/day (n=167), those who underwent urodynamic investigation were selected (n=76). The data of this study were retrieved from the records of Ankara University Cebeci Hospital and based on the AUM findings of single voiding cycle of women with OAB. AUM, which is among the institutionally approved primary urodynamic investigation methods, is performed with LUNA ambulatory monitoring recorder (MMS™) in the clinical setting with a standardized technique, in reproducing lower urinary tract symptoms of women since 2011. The relationship of the urodynamic data with the clinical findings were evaluated. RESULTS: AUM traces of women (n=76) with OAB revealed 63.1% DO, 64.4% urgency and 77.7% urinary incontinence of which were 14.4% urgency urinary incontinence (UUI), 25% stress urinary incontinence (SUI) and 38.1% mixed urinary incontinence (MUI). OAB patients with DO reported more urinary incontinence episodes/day, nocturia and mixed urinary incontinence in the voiding diary (p<0.04) and had significantly higher irritative symptom bother reflected by the questionnaires (p<0.04). Women with DO were more likely to be postmenopausal (p=0.02) and were found to have more urgency (p<0.001), urgency episodes (p=0.05) and incontinence (urge and mixed) (p<0.001). However, no association was found between the extent of pelvic organ prolapse and the presence of DO. CONCLUSIONS: AUM performed with a standardized technique during single voiding cycle seems to be a reliable method in reproducing symptoms of women with OAB. It provides both clinically relevant findings and objective documentation of urgency which is the main symptom for OAB. The detection of DO according to the ICS definition were also found to be concordant with urodynamicaly observed urgency and urinary incontinence. Objective and subjective clinical findings of OAB were found to be more severe in women with DO.