Can Stress Urinary Incontinence Be Predicted by Ultrasound?

Urethral tissue characterization using multiparametric ultrasound imaging

A decrease in urethral closure pressure is one of the primary causes of stress urinary incontinence in women. Atrophy of the urethral muscles is a primary factor in the 15 % age-related decline in urethral closure pressure per decade. Incontinence not only affects the well-being of women but is also a leading cause of nursing home admission. The objective of this research was to develop a noninvasive test to assess urethral tissue microenvironmental changes using multiparametric ultrasound (mpUS) imaging technique. Transperineal B-scan ultrasound (US) data were captured using clinical scanners equipped with curvilinear or linear transducers. Imaging was performed on volunteers from our institution medical center (n = 15, 22 to 76 y.o.) during Valsalva maneuvers. After expert delineation of the region of interest in each frame, the central axis of the urethra was automatically defined to determine the angle between the urethra and the US beam for further analysis. By integrating angle-dependent backscatter with radiomic texture feature analysis, a mpUS technique was developed to identify biomarkers that reflect subtle microstructural changes expected within the urethral tissue. The process was repeated when the urethra and US beam were at a fixed angle. Texture selection was conducted for both angle-dependent and angle-independent results to remove redundancies. Ultimately, a distinct biomarker was derived using a random forest regression model to compute the urethra score based on features selected from both processes. Angle-dependent backscatter analysis shows that the calculated slope of US mean image intensity decreased by 0.89 (±0.31) % annually, consistent with the expected atrophic disorganization of urethral tissue structure and the associated reduction in urethral closure pressure with age. Additionally, textural analysis performed at a specific angle (i.e., 40 degrees) revealed changes in gray level nonuniformity, skewness, and correlation by 0.08 (±0.04) %, -2.16 (±1.14) %, and -0.32 (±0.35) % per year, respectively. The urethra score was ultimately determined by combining data selected from both angle-dependent and angle-independent analysis strategies using a random forest regression model with age, yielding an R2 value of 0.96 and a p-value less than 0.001. The proposed mpUS tissue characterization technique not only holds promise for guiding future urethral tissue characterization studies without the need for tissue biopsies or invasive functional testing but also aims to minimize observer-induced variability. By leveraging mpUS imaging strategies that account for angle dependence, it provides more accurate assessments. Notably, the urethra score, calculated from US images that reflect tissue microstructural changes, serves as a potential biomarker providing clinicians with deeper insight into urethral tissue function and may aid in diagnosing and managing related conditions while helping to determine the causes of incontinence.

Comparison of urethral parameters in females presenting cystoceles with and without stress urinary incontinence based on dynamic magnetic resonance imaging: are they different?

PURPOSE

To compare urethral parameters between cystocele patients with and without stress urinary incontinence (SUI) and explore factors influencing SUI in cystocele patients via dynamic MRI.

METHODS

The two-dimensional parameters evaluated included the paravaginal defects, levator ani muscle defects, urethral length, urethral funnel shape, bladder neck funnel width, bladder neck funnel depth, urethral angle, posterior vesicourethral angle, and anterior bladder protrusion. The three-dimensional parameters included the proximal urethra rotation angle, the distal urethra rotation angle, bladder neck mobility, urethral midpoint mobility, and external urethral meatus mobility. The independent samples t test was used for continuous variables, and the chi-square test was used for categorical variables. Binary logistic regression was used to identify factors independently associated with SUI in cystocele patients.

RESULTS

The baseline parameters were similar between the 2 groups. Cystocele patients with SUI had a significantly higher point Aa (1.63 ± 1.06 cm vs. 0.81 ± 1.51 cm, p = 0.008); more anterior bladder protrusion (33.3% vs. 11.4%, p = 0.017); greater bladder neck mobility (36.38 ± 11.46 mm vs. 28.81 ± 11.72 mm, p = 0.005); mid-urethral mobility (22.94 ± 6.50 mm vs. 19.23 ± 6.65 mm, p = 0.014); and external urethral meatus mobility (22.42 ± 8.16 mm vs. 18.03 ± 8.51 mm, p = 0.022) than did cystocele patients without SUI. The other urethral parameters were similar in the groups (p > 0.05). Binary logistic regression showed that bladder neck mobility was independently associated with SUI in females with cystoceles (odds ratio, 1.06; 95% CI 1.015-1.107; p = 0.009).

CONCLUSION

Cystocele patients with SUI have a higher point Aa, more anterior bladder protrusion, and greater urethral mobility than those without SUI. Bladder neck mobility is independently associated with SUI in females with cystoceles.

REGISTRATION NUMBER

NCT03146195.

Development and Validation of a Risk Prediction Model for Female Stress Urinary Incontinence in Rural Fujian, China

Purpose

With China's rapidly aging population and the rising proportion of obese people, an increase in the number of women suffering from urinary incontinence (UI) is to be expected. In order to identify high-risk groups before leakage occurs, we aimed to develop and validate a model to predict the risk of stress UI (SUI) in rural women.

Patients and methods

This study included women aged 20-70 years in rural Fujian who participated in an epidemiologic survey of female UI conducted between June and October 2022. Subsequently the data was randomly divided into training and validation sets in a ratio of 7:3. Univariate and multivariate logistic regression analyses were used to identify independent risk factors as well as to further construct a nomogram for risk prediction. Finally, concordance index (C-index), calibration curve and decision curve analysis were applied to evaluate the performance of the predictive models.

Results

A total of 5290 rural females were enrolled, of whom 771 (14.6%) had SUI. Age, body mass index (BMI), postmenopausal status, number of vaginal deliveries, vaginal delivery of large infant, constipation and family history of pelvic organ prolapse (POP) and SUI were included in the nomogram. C-index of this prediction model for the training and validation sets was 0.835 (95% confidence interval [CI] = 0.818-0.851) and 0.829 (95% CI = 0.796-0.858), respectively, and the calibration curves and decision analysis curves for both the training and validation sets showed that the model was well-calibrated and had a positive net benefit.

Conclusion

This model accurately estimated the SUI risk of rural women in Fujian, which may serve as an effective primary screening tool for the early identification of SUI risk and provide a basis for further implementation of individualized early intervention. Moreover, the model is concise and intuitive, which makes it more operational for rural women with scarce medical resources.

Machine learning in female urinary incontinence: A scoping review

Introduction and Hypothesis

The aim was to conduct a scoping review of the literature on the use of machine learning (ML) in female urinary incontinence (UI) over the last decade.

Methods

A systematic search was performed among the Medline, Google Scholar, PubMed, and Web of Science databases using the following keywords: [Urinary incontinence] and [(Machine learning) or (Predict) or (Prediction model)]. Eligible studies were considered to have applied ML model to explore different management processes of female UI. Data analyzed included the field of application, type of ML, input variables, and results of model validation.

Results

A total of 798 papers were identified while 23 finally met the inclusion criteria. The vast majority of studies applied logistic regression to establish models (91.3%, 21/23). Most frequently ML was applied to predict postpartum UI (39.1%, 9/23), followed by de novo incontinence after pelvic floor surgery (34.8%, 8/23).There are also three papers using ML models to predict treatment outcomes and three papers using ML models to assist in diagnosis. Variables for modeling included demographic characteristics, clinical data, pelvic floor ultrasound, and urodynamic parameters. The area under receiver operating characteristic curve of these models fluctuated from 0.56 to 0.95, and only 11 studies reported sensitivity and specificity, with sensitivity ranging from 20% to 96.2% and specificity from 59.8% to 94.5%.

Conclusion

Machine learning modeling demonstrated good predictive and diagnostic abilities in some aspects of female UI, showing its promising prospects in near future. However, the lack of standardization and transparency in the validation and evaluation of the models, and the insufficient external validation greatly diminished the applicability and reproducibility, thus a focus on filling this gap is strongly recommended for future research.

Nomogram Analysis Based on Clinical and Sonographic Characteristics for the Assessment of Postpartum Stress Urinary Incontinence

OBJECTIVES

We aimed to develop and validate a nomogram integrating clinical and sonographic characteristics for the individualized SUI risk evaluation in the early postpartum stage.

METHODS

This was a prospective cross-sectional study. From June 2020 to September 2022, singleton primiparas who underwent TPUS examination at 6-8 weeks postpartum were recruited. They were divided into the training and validation cohorts at a ratio of 8:2 according to the temporal split. All subjects were interviewed before TPUS examination. Univariate and multivariate logistic analyses were performed to develop three models: the clinical, sonographic, and combined models. The ROC curve was plotted to evaluate model discrimination ability. Finally, the combined model was selected to establish the nomogram. The nomogram's discrimination, calibration, and clinical usefulness were evaluated in the training and validation cohorts.

RESULTS

The performance of the combined model was better than that of the clinical and sonographic models. Six predictors (BMI, delivery mode, lateral episiotomy, SUI during pregnancy, cystocele, and bladder neck funneling) remained in the combined model. The nomogram based on the combined model had good discrimination with AUCs of 0.848 (95% CI: 0.796-0.900) and 0.872 (95% CI: 0.789-0.955) in the training and validation cohorts, respectively, and the calibration curve showed good efficiency in assessing postpartum SUI. Decision curve analysis showed that the nomogram was clinically useful.

CONCLUSIONS

The nomogram based on clinical and sonographic characteristics showed good efficiency in assessing postpartum SUI risk and can be a convenient and reliable tool for individual SUI risk assessment.

Validation of an automatic method for reconstruction, delineation, and measurement of levator hiatus in clinical practice

OBJECTIVES

To evaluate the concordance between an automatic software program and manual evaluation in reconstructing, delineating, and measuring the levator hiatus (LH) on maximal Valsalva maneuver.

METHODS

This was a retrospective study analyzing archived raw ultrasound imaging data of 100 patients underwent transperineal ultrasound (TPUS) examination. Each data were assessed by the automatic Smart Pelvic System software program and manual evaluation. The Dice similarity index (DSI), mean absolute distance (MAD), and Hausdorff distance (HDD) were calculated to quantify delineation accuracy of LH. Agreement between automatic and manual measurement of levator hiatus area was assessed by intraclass correlation coefficient (ICC) and Bland-Altman method.

RESULTS

The satisfaction rate of automatic reconstruction was 94%. Six images were recognized as unsatisfactory reconstructed images for some gas in the rectum and anal canal. Compared with satisfactory reconstructed images, DSI of unsatisfactory reconstructed images was lower, MAD and HDD were larger (p = 0.001, p = 0.001, p = 0.006, respectively). The ICC was up to 0.987 in 94 satisfactory reconstructed images.

CONCLUSIONS

The Smart Pelvic System software program had good performance in reconstruction, delineation, and measurement of LH on maximal Valsalva maneuver in clinical practice, despite misidentification of the border of posterior aspect of LH due to the influence of gas in the rectum.

Effect evaluation and influencing factor analysis of vaginal carbon dioxide laser in the treatment of stress urinary incontinence

To evaluate the clinical efficacy of carbon dioxide laser in the treatment of female stress urinary incontinence and analyze the influencing factors. A total of 46 patients with stress urinary incontinence treated in the Affiliated Hospital of Nantong University from March 2021 to August 2022 were included through strict inclusion criteria and exclusion criteria. All patients were treated with transvaginal carbon dioxide laser therapy, and Patient Global Impression of Change (PGI-C) was used to evaluate patients' subjective satisfaction after treatment. The efficacy was evaluated by patient's subjective assessment of leakage, IngelmanSundberg scale, 1-h urine pad test, and international consultation on incontinence questionnaire short form (ICI-Q-SF) before and after treatment, and the adverse reactions after treatment were recorded. The treatment effect was divided into "significant effect group" and "no significant effect group" by subjective satisfaction and post-treatment-related scale evaluation. After laser treatment, patients' subjective symptom improved, the volume of 1-h urine pad test was reduced, and the ICI-Q-SF score was decreased, and the differences were statistically significant (P < 0.05). There was no significant difference in IngelmanSundberg scale before and after treatment (P = 1.00). Multivariate logistic regression analysis showed that pad test volume was significantly correlated with treatment effect (P = 0.007). Transvaginal carbon dioxide laser is a safe and effective method for the treatment of mild to moderate stress urinary incontinence in females. The less severe the urinary leakage, the better the treatment effect.

Visualized Urethral Mobility Profile During Urine Leakage in Supine and Standing Positions

OBJECTIVES

To describe the urethral course and position during urine leakage based on the visualized urethral mobility profile (UMP) and to explore the differences between supine and standing positions.

METHOD

This was a prospective study of 100 women with SUI and 100 control women who underwent a cough stress test (CST) with transperineal ultrasound (TPUS) in supine and standing positions. In the mid-sagittal plane, the UMP software automatically placed six equidistant points from the bladder neck (point 1) to the external urethral meatus (point 6). It determined the x and y coordinates of the points relative to the symphysis pubis. The distance between the points and symphysis pubis (dist. 1 to 6) was calculated using the formula SQRT (x2 + y2). The visualized UMP was created by reproducing the six points on a bitmap.

RESULTS

Valid UMP data of 78 control women and 90 women with SUI were analyzed. In the two positions, distances 1 to 6 were significantly greater in the SUI group than the continent group (all p < 0.05). During Valsalva, the distance between the mid-urethra (dist. 3 and 4) and the symphysis was significantly increased (all p < 0.001) in the SUI group. The visualized UMP showed a similar upper-urethral course in the two groups. The gap between the mid-urethra (points 3 and 4) and symphysis was wider in the SUI group.

CONCLUSION

The visualized UMP in supine and standing positions showed no difference in the bladder neck and upper urethral stability between incontinent and continent women, but mid-urethral stability was weaker in SUI.

Perineal ultrasound to assess the urethral spatial movement in stress urinary incontinence in women

BACKGROUND

Perineal ultrasound as a non-invasive method for the diagnosis of female stress urinary incontinence has attracted more and more attention. However, the criteria for stress urinary incontinence in women using perineal ultrasound have not been fully established. Our study aimed to evaluate characteristics of the urethral spatial movement with perineal ultrasonography.

METHODS

A total of 136 female patients with stress urinary incontinence and 44 controls were enrolled. Stress urinary incontinence was diagnosed using the International Consultation on Incontinence Questionnaire Short Form, medical history and physical examination, and severity was assessed using a 1 h pad test. We described the mobility of four equidistant points (A-D) located along the urethra length. The retrovesical and urethral rotation angles were measured using perineal ultrasonography at rest and during the maximal Valsalva maneuver.

RESULTS

Patients with stress urinary incontinence showed a more significant vertical movement at Points A, B and C than controls. The mean variations in the retrovesical angle were significantly larger in patients with stress urinary incontinence at rest and during the Valsalva maneuver than in controls (21.0 ± 16.5° vs. 14.7 ± 20.1°, respectively). The cut-off value for the retrovesical angle variation was 10.7° with 72% sensitivity and 54% specificity. There was a receiver-operating characteristic curve area of 0.73 and 0.72 for Points A and B, respectively. A cut-off of 10.8 mm, and 9.4 mm provided 71% sensitivity and 68% specificity and 67% sensitivity and 75% specificity, respectively.

CONCLUSIONS

The spatial movement of the bladder neck and proximal urethra, and variations in the retrovesical angle may be correlated with clinical symptoms and facilitate to the assessment of SUI.

Hiatal failure: effects of pregnancy, delivery, and pelvic floor disorders on level III factors

INTRODUCTION AND HYPOTHESIS

The failure of the levator hiatus (LH) and urogenital hiatus (UGH) to remain closed is not only associated with pelvic floor disorders, but also contributes to recurrence after surgical repair. Pregnancy and vaginal birth are key events affecting this closure. An understanding of normal and failed hiatal closure is necessary to understand, manage, and prevent pelvic floor disorders.

METHODS

This narrative review was conducted by applying the keywords "levator hiatus" OR "genital hiatus" OR "urogenital hiatus" in PubMed. Articles that reported hiatal size related to pelvic floor disorders and pregnancy were chosen. Weighted averages for hiatal size were calculated for each clinical situation.

RESULTS

Women with prolapse have a 22% and 30% larger LH area measured by ultrasound at rest and during Valsalva than parous women with normal support. Women with persistently enlarged UGH have 2-3 times higher postoperative failure rates after surgery for prolapse. During pregnancy, the LH area at Valsalva increases by 29% from the first to the third trimester in preparation for childbirth. The enlarged postpartum hiatus recovers over time, but does not return to nulliparous size after vaginal birth. Levator muscle injury during vaginal birth, especially forceps-assisted, is associated with increases in hiatal size; however, it only explains a portion of hiatus variation-the rest can be explained by pelvic muscle function and possibly injury to other level III structures.

CONCLUSIONS

Failed hiatal closure is strongly related to pelvic floor disorders. Vaginal birth and levator injury are primary factors affecting this important mechanism.

The Clinical Effects of Pixel CO2 Laser on Bladder Neck and Stress Urinary Incontinence

Background: Our study aims to assess Pixel CO2 laser efficacy for female stress urinary incontinence (SUI). Methods: In the study, 25 women with SUI were included and scheduled for vaginal Pixel CO2 Laser (FemiLift™, Alma Lasers, Israel) treatment. All subjects had a baseline and 6-month post-treatment assessment that included three-dimensional perineal ultrasound and validated questionnaires. Results: Data showed that monthly three-session vaginal Pixel CO2 Laser treatment significantly improved SUI symptoms, as evidenced by validated questionnaires, including UDI-6, IIQ-7, ICIQ, and vaginal laxity questionnaire (p < 0.05). The Pixel CO2 Laser efficacy in vaginal treatment was 20/25 (80%), and the perineal sonography showed that laser treatment significantly decreased bladder neck mobility and middle urethral area (during resting and straining). Permanent adverse events were not found. Conclusions: The results of our study suggested that for the treatment of mild to moderate SUI symptoms, Pixel CO2 Laser is effective and safe; however, more studies and a longer follow-up should be conducted to confirm its efficacy and durability.

The Visualized Urethral Mobility Profile in Stress Urinary Incontinence Described by Four-Dimensional Transperineal Ultrasound

OBJECTIVES

To describe the urethral mobility during urine leaking in stress urinary incontinence (SUI) by transperineal ultrasound (TPUS) with urethral mobility profile (UMP) analysis.

METHODS

This was a prospective study of 380 women who had a cough stress test (CST) with TPUS. UMP software automatically placed six equidistant points from the bladder neck (Point 1) to the external urethral meatus (Point 6) and determined their x and y coordinates relative to the symphysis pubis. Urethral mobility vector of Points 1-6 (Vectors 1-6) and the distance between the six points and the symphysis (Dist. 1-6) were calculated and compared between the two groups. The visualized UMP was created by reproducing the positions of the six points at rest and on Valsalva.

RESULTS

Valid data of 188 women with SUI and 174 continent women were analyzed. The mean age of all 362 women was 49.3 years. Mean body mass index in the SUI group was significantly increased (23.8 vs 22.2 kg/m² , P < .001). During CST, Vectors 1-6 and Dist. 2-6 were significantly increased (all P < .005) in the SUI group. The UMP showed the mid-urethral rotated down around the symphysis pubis. The upper urethral profile in the two groups was similar. But the gap between the mid-urethra and the symphysis was wider in the SUI group.

CONCLUSIONS

The visualized UMP illustrated the mid-urethral hypermobility in SUI by showing a wider gap due to the unstable connection between the mid-urethra and the symphysis pubis.

Pelvic Floor Muscle Strength in the First Trimester of Primipara: A Cross-Sectional Study

Background: Pelvic floor muscle (PFM) weakness is associated with stress urinary incontinence. Pregnancy is an important risk factor for PFM weakness. Studies evaluating PFM strength in the first trimester of pregnancy are still lacking. Our study aimed to describe pelvic floor function of the primipara in the first trimester of gestation and investigate the risk factors for PFM weakness. Methods: Primiparas aged 20~40 years with a singleton pregnancy less than 14 weeks of gestation were recruited, and data were collected via questionnaires on items that were suggested as associated with PFM weakness, followed by Modified Oxford Scale (MOS) on genital hiatus and perineal body and pelvic floor ultrasound evaluation for the thickness of the left and right levator ani muscles (LAM), right−left diameter of the levator hiatus (LH), and LH area. Participants were divided into three groups by MOS >3, =3, and <3 for data analysis. Results: A total of 380 participants completed the questionnaires and examinational analysis, of whom, 228, 98, and 54 were divided into Group 1, Group 2, and Group 3, respectively. The three groups were significantly different in the number of gestations and abortions, toilet types, and the right−left diameter of the LH (p < 0.05). Logistic regressive analysis showed that squatting toilet dominant (OR = 3.025; 95% CI: 1.623~5.638; p < 0.001) and a larger right−left diameter of the LH (OR = 1.065; 95% CI: 1.026~1.105; p = 0.001) were significantly associated with PFM weakness. Conclusions: Squatting toilet dominancy and longer right−left diameter of the LH are significantly associated with PFM weakness in primiparas in the first trimester. Sitting toilets should be recommended to women, especially pregnant women. Trial registration: The trial has been registered at Chinese Clinical Trial Registry (registration number: ChiCTR2000029618).

The Association of Hiatal Dimensions and Urethral Mobility With Stress Urinary Incontinence

OBJECTIVES

To investigate the association of hiatal area (HA), bladder neck mobility, and urethral mobility during the cough stress test (CST) with stress urinary incontinence (SUI).

METHODS

This was a prospective study of 110 continent and 190 incontinent women using transperineal ultrasound. HA, bladder neck mobility, and the mobility of six points along the urethra (Vectors 1-6) were measured. The cohort was randomly divided at a ratio of 2:1 into a training cohort and a validation cohort. The correlations of HA with bladder neck mobility, urethral mobility, and SUI were tested. The predictive model was yielded by fisher linear discriminant analysis and receiver operating characteristics to assess the parameters' ability to predict SUI.

RESULTS

Valid data were collected from 177 incontinent women and 105 continent women. Significant differences were identified in HA, body mass index (BMI), funneling, bladder neck mobility, and Vectors 1-6 between them. HA was positively correlated to bladder neck mobility. In the training cohort, bladder neck position on Valsalva, Vectors 3, and BMI had the area under curves of 0.74, 0.69, and 0.66 (all P < 0.001); Funneling and Vector 3 had odds ratios of 18.96 and 3.65 (all P < 0.001), for predicting SUI. The predictive model incorporating funneling, Vectors 3, and BMI provided the best performance in predicting SUI in both cohorts.

CONCLUSION

The larger the HA was, the higher the bladder neck mobility. However, it was mid-urethral mobility rather than bladder neck mobility that performed best at predicting SUI.

The role of transperineal ultrasound in the evaluation of stress urinary incontinence cases

Purpose:

To evaluate the use of transperineal ultrasonography while diagnosing stress urinary incontinence (SUI) by comparing the urethral angle (α), posterior urethrovesical angle (β), and bladder neck descent (BND) during rest and Valsalva maneuver in continent women and women with SUI.

Materials and methods:

This prospective observational study was conducted with 50 women with SUI and 50 continent women. Transperineal ultrasonography was performed at rest and during Valsalva maneuver. Q-tip test was performed.

Results:

During the Valsalva maneuver, both α and β angles were significantly higher in women with SUI (p <0.001). The difference between Valsalva and rest measurements of α and β angles (R α, R β) were also significantly higher in women with SUI (p <0.001). The cut-off point determined for the R α in the diagnosis of stress incontinence was 16° (80% sensitivity, 98% specificity). A statistically significant strong correlation was found between Q-tip test angle and R α value (p=0.000; r=0.890). Q-tip VAS pain scores were significantly higher than ultrasonography VAS pain scores (p <0.001). In relation to the bladder neck descent comparison between the two groups showed that BND was significantly higher in SUI group (p <0.001). The cut-off point determined for BND in the diagnosis of SUI was >11mm (90% sensitivity, 98% specificity).

Conclusion:

Transperineal ultrasonography is a practical, reliable, non-invasive and comfortable method for evaluation of SUI. It has the advantage of dynamic evaluation during the Valsalva maneuver. Rotation angles and BND have high sensitivity and specificity for detection of SUI. The change in α angle with Valsalva (Rα) can be used as an alternative to Q-tip test.

Artificial intelligence models derived from 2D transperineal ultrasound images in the clinical diagnosis of stress urinary incontinence

INTRODUCTION AND HYPOTHESIS

The aim of the study was to develop artificial intelligence (AI) algorithms using 2D transperineal ultrasound (TPUS) static images to simplify the clinical process of diagnosing stress urinary incontinence (SUI) in practice.

METHODS

The study involved 400 patients in total, including 265 SUI patients and 135 non-SUI patients who underwent a routine clinical evaluation process by urologists and TPUS. They were classified into different groups based on the International Consultation on Incontinence Questionnaire (ICIQ) to assess the impact of inconvenience on patients' lives. Four AI models were developed by 2D TPUS images: Model A (a single-mode model based on Valsalva maneuver images to classify G-0, G-1, and G-2); Model B (a dual-mode model based on Valsalva maneuver and resting state images to classify G-0, G-1, and G-2); Model C (a single-mode model based on Valsalva maneuver images to classify G-2 and G-01); Model D (a dual-mode model based on Valsalva maneuver and resting state images to classify G-2 and G-01). The performance of the four models was evaluated by confusion matrices and the area under the receiver-operating characteristic curve (AUC).

RESULTS

The dual-mode model based on the Valsalva maneuver and resting-state images (Model D) had a higher accuracy of 86.3% and an AUC of 0.922, which was significantly higher than the AUCs of the other three models: 0.771, 0.862, and 0.827.

CONCLUSIONS

The AI algorithm using 2D TPUS static images of the Valsalva maneuver and resting state may be a promising tool in the diagnosis of SUI patients in to relieve clinical processes in practice given its ease of use in clinical applications.

Does size matter? Perineometer and digital examination of a model levator hiatus

INTRODUCTION

Evaluation of the female pelvic floor muscles is commonly carried out with digital examination and assigning a modified Oxford scale score or vaginal manometry. Racial differences can influence the size of the levator hiatus (LH) with "black" or African nulliparous women having a significantly larger LH compared to Caucasian women. The aim of this study was to assess the impact of LH size on manometry readings of simulated pelvic floor muscle contractions (PFMCs) using a small and large model LH.

METHODS

Small and large LH models were created using published data for size. Inflation of a pressure cuff placed circumferentially in the LH model represented a simulated PFMC. The models were examined in a supine position by three examiners and a perineometer twice each at varying simulated PFMC strength.

RESULTS

Positive correlation was found between increasing simulated PFMC strength with a higher Oxford score following digital examination and manometry readings for both the small (r_s  = .87, r_s  = .98) and large (r_s  = .95, r_s  = .87) models. There was good to excellent inter and intraobserver correlation for digital assessment of both models. The manometry measurements showed a much larger incremental rise from baseline in the small model compared with the large model (P < .05).

CONCLUSION

This study demonstrates that perineometer readings are affected by natural variations in LH size and PFMC strength. Therefore improvement to pelvic floor strength cannot be interpreted and measurements cannot be compared with others unless the LH size is known or digital examination is carried out.