Structural support of the urethra as it relates to stress urinary incontinence: the hammock hypothesis

The female urethral closure mechanism during physical stress

The closure of the urethra under the condition of stress is the result of a reflex contraction of the urethral rhabdosphincter and pelvic floor muscles. This is likely induced by activity of the abdominal muscles due to a sudden increase in abdominal pressure. This reflex contraction with an increase of urethral pressure occurs a few milliseconds before an increase in intraabdominal pressure. The urethral pressure increase during stress is only possible with fixation of the urethra by the pubourethral ligaments (PUL), facilitating urethral kinking. The highest and most important increase in pressure and resistance occurs in the distal urethra due to this kinking of the urethra.

Expression of insulin-like growth factor binding protein 5 in the vaginal wall tissues of older women with pelvic organ prolapse

This study aimed to investigate the expression and significance of insulin-like growth factor binding protein 5 (IGFBP5) and extracellular matrix (ECM) related proteins in anterior vaginal wall tissues among aged pelvic organ prolapse (POP) patients. Tissues from the anterior vaginal wall were collected from 28 patients with POP and 20 patients without POP. The expression of protein and mRNA levels of IGFBP5 and ECM related proteins were evaluated in the vaginal wall tissues using immunohistochemistry, western blotting, and RT-qPCR techniques. The expression levels were then compared with clinical parameters. The expression levels of protein and mRNA of IGFBP5, collagen I, and collagen III were significantly lower in the POP group. Protein and mRNA expression levels of MMP2 were significantly higher in the POP group. IGFBP5 protein and mRNA expression levels were negatively correlated with age and significantly lower in older POP patients (≥ 65 years old) compared to younger POP patients (< 65 years old). IGFBP5 protein and mRNA expression levels were also significantly lower in POP-Q stage IV patients compared to POP-Q stage III patients. IGFBP5 expression level is negatively correlated with the age and severity of prolapse. The significant decrease in IGFBP5 expression may play a crucial part in the aging process and the occurrence of POP.

Evaluation of pelvic structural abnormalities in primiparous women with stress urinary incontinence

INTRODUCTION AND HYPOTHESIS

The objective was to evaluate the morphological characteristics of pelvic floor structure specific to de novo stress urinary incontinence (SUI) in primiparous women using three-dimensional (3D) reconstruction fusion technology based on static MRI combined with dynamic MRI.

METHODS

Eighty-one primiparous women after the first vaginal delivery were studied, 40 with SUI and 41 without SUI. 3D reconstruction models based on static MRI were used to describe the anatomical abnormalities of pelvic floor tissues. Dynamic MRI was used to describe segmental activities of the urethra and vagina. The relationship between the morphometry and postpartum SUI was evaluated by logistic regression analysis and receiver operator characteristic curve.

RESULTS

The differences in the distance from the bladder neck to the pubic symphysis (BSD), the angle between the posterior wall of the urethra and the anterior wall of the vagina, the width of the distal region of the vagina, urethral length, urethral compression muscle volume (CUV), and pubovisceral muscle volume, puborectal muscle volume, were measured, and except for the extremity of the anterior urethral wall, the total displacements (TDs) of the other sites between the two groups were statistically significant (p < 0.05). Logistic regression analysis showed that the BSD decreased, the CUV decreased, the TDs of the first site and the eighth site increment correlated significantly with postpartum SUI occurrence (p < 0.05).

CONCLUSIONS

3D reconstruction fusion technology provides an important support for a precise assessment of the pelvic floor dysfunction. The BSD, CUV, and iliococcygeus muscle volume have certain values in predicting de novo SUI after first vaginal birth.

On a potential morpho-mechanical link between the gluteus maximus muscle and pelvic floor tissues

Stress urinary incontinence presents a condition not only found in female elderlies, but also in young athletes participating in high-impact sports such as volleyball or trampolining. Repeated jumps appear to be a predisposing factor. Yet the pathophysiology remains incompletely elucidated to date; especially with regard to the influence of the surrounding buttock tissues including gluteus maximus. The present study assessed the morpho-mechanical link between gluteus maximus and the pelvic floor female bodies. 25 pelves obtained from Thiel embalmed females were studied in a supine position. Strands of tissues connecting gluteus maximus with the pelvic floor obtained from 20 sides were assessed mechanically. Plastinates were evaluated to verify the dissection findings. In total, 49 hemipelves were included for data acquisition. The fascia of gluteus maximus yielded connections to the subcutaneous tissues, the fascia of the external anal sphincter and that of obturator internus and to the fascia of the urogenital diaphragm. The connection between gluteus maximus and the urogenital diaphragm withstood an average force of 23.6 ± 17.3 N. Cramér φ analyses demonstrated that the connections of the fasciae connecting gluteus maximus with its surroundings were consistent in the horizontal and sagittal planes, respectively. In conclusion, gluteus maximus is morphologically densely linked to the pelvic floor via strands of connective tissues investing the adjacent muscles. Though gluteus maximus has also been reported to facilitate urinary continence, the here presented morpho-mechanical link suggests that it may also have the potential to contribute to urinary stress incontinence. Future research combining clinical imaging with in-situ testing may help substantiate the potential influence from a clinical perspective.

Efficacy of Pelvic Floor Ultrasound for Assessing Transobturator Tape Sling Procedure

IMPORTANCE

Complications after midurethral sling, which require a high degree of clinical suspicion for timely diagnosis, accurate evaluation, and proper intervention, are closely associated with surgical success or failure.

OBJECTIVES

This study aimed to evaluate the efficacy and complications of tension-free midurethral sling for stress urinary incontinence (SUI) using pelvic floor ultrasound.

STUDY DESIGN

This retrospective study included 152 female patients with SUI admitted to the Jinhua Central Hospital between January 2020 and December 2021 who were selected. All patients underwent midurethral transobturator tape sling procedures and were divided into success, voiding dysfunction, overactive bladder, and failure groups according to postoperative efficacy and complications. The pelvic floor ultrasound examination was performed before and after the surgery.

RESULTS

The posterior vesicourethral angle difference ( P < 0.01) was significantly lower after the surgery than before the surgery. The rate of bladder neck funneling ( P < 0.01) and the area of bladder neck funneling ( P < 0.01) were smaller after the surgery than before the surgery. The tape-longitudinal smooth muscle distance, the tape-symphysis pubis distance, the sling angle, and the tape-bladder neck/urethra increased successively in the voiding dysfunction, overactive bladder, success, and failure groups.

CONCLUSIONS

Pelvic floor ultrasound can accurately evaluate the postoperative efficacy and complications of transobturator tape sling procedures for SUI and can reasonably guide the management of complications. Therefore, it is an effective imaging method for postoperative follow-up after tension-free midurethral tape suspension.

Multiparity Reduces Urethral and Vaginal Pressures Following the Bulboglandularis Muscle Stimulation in Rabbits

Unlike male mammals showing a well-delimited external urethral sphincter, female mammals have urogenital sphincters shaped by muscles like the urethrovaginal sphincter. Childbirth-related injuries affect morphometry and function of urogenital sphincters in women, which frequently underlies pelvic floor disorders, including stress urinary incontinence and pelvic organ prolapse. The bulboglandularis muscle (Bgm) seems to shape a urogenital sphincter in rabbits. We determined herein the effect of multiparity on urethral and vaginal pressures generated by the Bgm stimulation in age-matched nulliparous and multiparous chinchilla-breed rabbits to stimulate the Bgm with trains of ascending frequencies (from 1 to 100 Hz; 4 s duration each). Subsequently, the Bgm was excised, measured in width, and weighed. Significant differences (P ≤ 0.05) were determined with Mann-Whitney U or Student t-tests or repeated measures two-way ANOVA followed by Tukey tests. Spearman's partial coefficients were calculated to investigate the correlation between the highest pressure (urethral or vaginal) and the Bgm width. Multiparity reduced the weight and the width in the Bgm origin and medial regions. Urethral and vaginal pressures increased in response to the electrical stimulation of Bgm with frequencies from 20 to 100 Hz. Multiparas showed significant reductions in both types of pressures. We detected a strong correlation (conditioned by multiparity) between the medial Bgm width and the highest vaginal pressure. Our present findings demonstrate that multiparity impairs the function of Bgm, resulting in diminished urethral and vaginal pressures. Furthermore, the significant narrowness of the Bgm was correlated with the vaginal pressure recorded.

A 3D finite element model of uterus support to evaluate mechanisms underlying uterine prolapse formation

Uterine prolapse (UP) seriously affects the quality of life and physical and mental health of elderly women, which can easily be caused by ligament injury or intra-abdominal pressure (IAP) increasing. The objective of this manuscript was to study the influence of IAP and ligament injury on uterus and its surrounding ligaments using the finite element method. First, the three-dimensional (3D) models of retroverted uterus and its surrounding ligaments were established, and loads and constraints were set in ABAQUS software, then the stress and deformation of uterine ligaments and uterine displacement were calculated. The study found that the uterine displacement and the stress and deformation of the ligaments increased when IAP and ligament injury increased alone or simultaneously. Then, the stress and sensitivity of the ligaments to the changes of IAP or ligament injury were in the order of uterosacral ligament (USL), broad ligament (BL), cardinal ligament (CL) and round ligament (RL), while the deformation and sensitivity the changes of the ligaments were in the order of BL > RL > USL > CL. Moreover, the ligament injury had a greater influence on the uterus and uterine ligaments than IAP. The results of this study can provide guidance for optimization of surgical scheme of uterus prolapsed in clinic and exploration of pathogenesis.

Differentiation of patient-specific void urine-derived human induced pluripotent stem cells to fibroblasts and skeletal muscle myocytes

Cell-based therapy is a major focus for treatment of stress urinary incontinence (SUI). However, derivation of primary cells requires tissue biopsies, which often have adverse effects on patients. A recent study used human induced pluripotent stem cells (iPSC)-derived smooth muscle myocytes for urethral sphincter regeneration in rats. Here, we establish a workflow using iPSC-derived fibroblasts and skeletal myocytes for urethral tissue regeneration: (1) Cells from voided urine of women were reprogrammed into iPSC. (2) The iPSC line U1 and hESC line H9 (control) were differentiated into fibroblasts expressing FSP1, TE7, vinculin, vimentin, αSMA, fibronectin and paxillin. (3) Myogenic differentiation of U1 and H9 was induced by small molecule CHIR99021 and confirmed by protein expression of myogenic factors PAX7, MYOD, MYOG, and MF20. Striated muscle cells enriched by FACS expressed NCAM1, TITIN, DESMIN, TNNT3. (4) Human iPSC-derived fibroblasts and myocytes were engrafted into the periurethral region of RNU rats. Injected cells were labelled with ferric nanoparticles and traced by Prussian Blue stain, human-specific nuclear protein KU80, and human anti-mitochondria antibody. This workflow allows the scalable derivation, culture, and in vivo tracing of patient-specific fibroblasts and myocytes, which can be assessed in rat SUI models to regenerate urethral damages and restore continence.

AbsorbaTack™ vs. ProTack™ vs. sutures: a biomechanical analysis of cervical fixation methods for laparoscopic apical fixations in the porcine model

PURPOSE

Treatment of pelvic organ prolapse (POP) often requires the use of synthetic mesh. In case of a novel and standardized bilateral apical fixation, both uterosacral ligaments are replaced by polyvinylidene-fluoride (PVDF) tapes. One of the main problems remains the fixation method, which should be stable, but also simple and quick to use. The current study evaluated biomechanical differences between the cervical tape fixation with sutures (group 1), non-absorbable tacks (group 2) and absorbable tacks (group 3) in an in vitro porcine model.

METHODS

A total of 28 trials, conducted in three groups, were performed on porcine, fresh cadaver uteri. All trials were performed until mesh, tissue or fixation device failure occurred. Primary endpoints were the biomechanical properties maximum load (N), displacement at failure (mm) and stiffness (N/mm). The failure mode was a secondary endpoint.

RESULTS

There was a significant difference between all three groups concerning the maximum load. Group 1 (sutures) supported a maximum load of 64 ± 15 N, group 2 (non-absorbable tacks) yielded 41 ± 10 N and group 3 (absorbable tacks) achieved 15 ± 8 N. The most common failure mode was a mesh failure for group 1 and 2 and a fixation device failure for group 3.

CONCLUSION

The PVDF-tape fixation with sutures supports 1.5 times the load that is supported by non-absorbable tacks and 4.2 times the load that is supported by absorbable tacks. Nevertheless, there was also a stable fixation through tacks. Sutures are the significantly stronger and cheaper fixation device but may prolong the surgical time in contrast to the use of tacks.

Advances in the molecular pathogenesis and cell therapy of stress urinary incontinence

Stress urinary incontinence (SUI) is very common in women. It affects patients' mental and physical health, and imposed huge socioeconomic pressure. The therapeutic effect of conservative treatment is limited, and depends heavily on patient persistence and compliance. Surgical treatment often brings procedure-related adverse complications and higher costs for patients. Therefore, it is necessary to better understand the potential molecular mechanisms underlying stress urinary incontinence and develop new treatment methods. Although some progress has been made in the basic research in recent years, the specific molecular pathogenic mechanisms of SUI are still unclear. Here, we reviewed the published studies on the molecular mechanisms associated with nerves, urethral muscles, periurethral connective tissue and hormones in the pathogenesis of SUI. In addition, we provide an update on the recent progresses in research on the use of cell therapy for treating SUI, including research on stem cells therapy, exosome differentiation and gene regulation.

Vaginal delivery effects on 3D morphology of the bladder, urethra, and vagina: a pilot study comparing women with different numbers of deliveries

PURPOSE

To explore 3D morphological changes of the bladder, urethra, and vagina following different numbers of vaginal deliveries.

METHODS

Sampled patients had undergone magnetic resonance imaging for gynecological diseases in Nanfang Hospital. A total of 167 patients who met the study inclusion and exclusion criteria were enrolled and divided into four groups. Mimics and UG software packages were used for reconstructions and measurements, and data were compared with one-way analyses of variance.

RESULTS

A total of 167 3D models were constructed, and eight parameters related to the bladder and urethra were measured (5 angles, 2 lengths, and 1 thickness). No statistically significant differences were found between subgroups, although mean plot figures of urethra pubic and α angles showed trends to increase with more deliveries, and the opposite trend was seen for the urethra tilt angle. There were no obvious trends between other parameters and delivery number. There were seven vaginal parameters (6 lengths and 1 shape). Mid-urethral and vaginal gap measurements tended to become wider as delivery number increased, and the opposite was seen for the distal gap. Mid-vaginal 2D cross-sectional shape and the proportion of shallow concave types also tended to significantly increase with more deliveries, especially after the third birth.

CONCLUSION

As the number of deliveries through the vagina increases, the lateral support function of this organ and the urethra become relatively weaker. These fine anatomical changes are related to delivery numbers and become most obvious after the third birth.

Simulation of the female pelvic mobility and vesical pressure changes employing fluid-structure interaction method

INTRODUCTION AND HYPOTHESIS

This study aims to develop a fluid-structural interaction (FSI) method to pinpoint the effects of pressure changes inside the bladder and their impact on the supporting structure and the urethra mobility.

METHODS

A physiological model of the nulliparous female pelvis, including the organs, supportive structures, and urine, was developed based on magnetic resonance images. Soft tissues with nonlinear hyperelastic material characteristics were modeled. The Navier-Stokes equations governing the fluid flow within the computational domain (urine) were solved. The urine and soft tissue interactions were simulated by the FSI method. The vesical pressure and its impact on the urethral mobility and supportive structures were investigated during the Valsalva maneuver. Moreover, the simulation results were validated by comparing with a urodynamic test and other research.

RESULTS

The results demonstrated that the vesical pressure simulated by the FSI method could predict the nonlinear behavior of the urodynamic test pressure. The urethra retropubic bladder neck and the bladder neck-pubic bone angle changed 58.92% and -55.76%, respectively. The retropubic urethral length distance changed by -48.74%. The error compared to the statistical results of other research is < 5%.

CONCLUSIONS

The total deformation and mobility of the urethra predicted by the FSI model were consistent with clinical observations in a subject. The urethra supports dependence on the tissues' mechanical properties, interaction between the tissues, and effect of urine fluid inside the bladder. This simulation effectively depicts the patterns of urethra mobility, which provides a better understanding of the behavior of the pelvic floor.

How about the RCTs' quality of acupuncture treatment for female urinary incontinence in recent 20 years? A report quality assessment

PURPOSE

To evaluate the quality of randomized controlled trials (RCTs) of acupuncture on female urinary incontinence (UI).

METHODS

We searched for related RCTs of acupuncture on female UI from seven databases (PubMed, Embase, Cochrane library, Web of Science, Medline, ClinicalKey, and Clinical trials). We applied CONSORT (2010 year) and STRICTA criteria to evaluate the relevant factors of included RCTs. Two trained researchers scored independently, and concordance was assessed by Cohen's к-statistic. The median and interquartile range summarized the CONSORT and STRICTA scores of the included studies. In addition, two independent sample t tests were used to assess the differences in the study quality between the 2000-2010 and the 2011-2022 years.

RESULTS

A total of 25 RCTs were finally included, and the scores were consistent between different assessors. The average CONSORT score was 10.50 (IQR 9.0-15.0) (total score was 25.0). Overall, the studies generally included scientific background (24/25, 96%), inclusion and exclusion criteria (24/25, 96%), outcome indicators (24/25, 96%), randomization methods (21/25, 84%), generalizability (19/25, 76%), and financial support (15/25, 60%). Most lacked sample size calculation (5/25, 20%), type of randomization (5/25, 20%), blinding (6/25, 24%), case screening period and follow-up (4/25, 16%), and study registration (6/25, 24%), etc. The average STRICTA score was 3.380 (IQR 3.02-3.95) (total score was 6.0). There had a lack of education on treatment methods for patients (3/25, 12%) and the qualification of acupuncturists (6/25, 24%).

CONCLUSION

The overall quality of RCTs on acupuncture treatment of female UI was suboptimal. It is still necessary to improve the research methods, especially the application of random methods, blinding, the interpretation of treatment, and the identification qualification of acupuncturists.

Secondary urethral sphincter function of the rabbit pelvic and perineal muscles

Perineal and pelvic floor muscles play an important role in continence by providing mechanical support to pelvic organs. It is also known that the pubococcygeus muscle (PcM) contracts in the storage phase and is inactive during voiding, while the bulbospongiosus muscle (BsM) is active during the voiding phase. Recent evidence suggested an additional role of these muscles in supporting urethral closure in rabbits. However, the individual role of perineal and pelvic muscles as urethral sphincters is not well-defined. Here we evaluated the individual, sequential and synergistic roles of the PcM and BsM in assisting urethral closure and defined the optimal electrical stimulation parameters that can effectively contract these muscles and increase the urethral pressure (P _ura ) in young nulliparous animals (n = 11). Unilateral stimulation of either the BsM or PcM at 40 Hz induced modest increases in average P _ura (0.23 ± 0.10 and 0.07 ± 0.04 mmHg, respectively). Investigation on the changes in P _ura evoked by stimulation frequencies between 5 and 60 Hz show that sequential contralateral PcM-BsM activation at 40 Hz induced a 2-fold average P _ura increase (0.23 ± 0.07 mmHg) compared to that evoked by PcM stimulation. Simultaneous activation of PcM and BsM at 40 Hz also showed an increased average P _ura (0.26 ± 0.04 mmHg), with a 2-fold increase in average P _ura observed during the unilateral sequential PcM-BsM stimulation at 40 Hz (0.69 ± 0.2 mmHg). Finally, stimulation at 40 Hz of the bulbospongiosus nerve (BsN) induced an approximate 4-fold increase in average P _ura (0.87 ± 0.44 mmHg; p < 0.04) compared to that elicited by BsM stimulation, confirming that direct nerve stimulation is more effective. Together, this study shows that in the female rabbit, both perineal and pelvic muscles support of the urethral function during continence, and that unilateral stimulation of the BsN at 40-60 Hz is sufficient to achieve maximal secondary sphincter activity. The results also support the potential clinical value of neuromodulation of pelvic and perineal nerves as bioelectronic therapy for stress urinary incontinence.

Puerarin protects fibroblasts against mechanical stretching injury through Nrf2/TGF-β1 signaling pathway

INTRODUCTION AND HYPOTHESIS

Stress urinary incontinence (SUI) is the most common form of urinary incontinence in women, which affects women's quality of life worldwide. Mechanical injury of the pelvic floor may disrupt the pelvic supportive tissues and connections via the remodeling of extracellular matrix (ECM), which is supposed to be one of the main pathological mechanisms of SUI.

METHODS

The SUI mouse model was established using vaginal distension (VD). Leak point pressure (LPP), maximum cystometric capacity (MCC), collagen, Nrf2 and TGF-β1 in the anterior vaginal wall were measured in either wild-type or Nrf2-knockout (Nrf2^-/^-) female C57BL/6 mice with or without puerarin treatment. Then, the mechanical stretching (MS) loaded on L929 cells was generated by a four-point bending device. mTGF-β1 or LY2109761 (an inhibitor of TGF-β1) was used to verify the protective effect of puerarin after Nrf2 knockdown or overexpression.

RESULTS

The collagen content of the anterior vaginal tissues in VD mice and LPP and MCC was decreased significantly. Besides, the expression levels of Nrf2, TGF-β1, collagen I and collagen III of MS group were downregulated in L929 cells. Puerarin pretreatment could reverse mechanical injury-induced collagen downregulation and Nrf2/TGF-β1 signaling inhibition. Moreover, both LY2109761 pretreatment and Nrf2 knockdown could attenuate the protective effect of puerarin in the mechanical injury-induced ECM remodeling, whereas exogenous TGF-β1 could counteract the effect of Nrf2 downregulation.

CONCLUSIONS

Puerarin protected fibroblasts from mechanical injury-induced ECM remodeling through the Nrf2/TGF-β1 signaling pathway. This might be a new strategy for the treatment of SUI.

Transobturator tape, tension-free vaginal tape, and transvaginal tension-free vaginal tape-obturator for the treatment of female stress urinary incontinence: A systematic review and network meta-analysis

OBJECTIVE

To systematically review the safety and effectiveness of tension-free vaginal tape (TVT), transobturator tape (TOT), and transvaginal tension-free vaginal tape-obturator (TVT-O) in the treatment of stress urinary incontinence (SUI).

METHODS

The PubMed, Embase, The Cochrane Library, Web of Science, WanFang Data, and CNKI were electronically searched. A total of 22 trials involving 3709 patients were included.

RESULTS

The objective cure rate was better with TVT than with TOT and TVT-O. The incidence of postoperative thigh/groin pain was lower with TVT than with TOT and TVT-O, but the incidence of dysuria was higher with TVT than with TVT-O. The incidence of lower urinary tract infection was higher with TVT than with TOT.

CONCLUSION

Tension-free vaginal tape may have a better outcome compared to TOT and TVT-O, but the risk of dysuria and lower urinary tract infection is higher with SUI.

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.

Urethral support in female urinary continence part 2: a computational, biomechanical analysis of Valsalva

INTRODUCTION AND HYPOTHESIS

In Part 1, we observed urethral mechanics during Valsalva that oppose current continence theories. In this study, we utilize a finite element model to elucidate the role of supportive tissues on the urethra during Valsalva. By determining the sensitivity of urethral motion and deformations to variations in tissue stiffnesses, we formulate new hypotheses regarding mechanisms of urethral passive closure.

METHODS

Anatomy was segmented from a nulliparous, continent woman at rest. The model was tuned such that urethral motion during Valsalva matched that observed in that patient. Urethra and surrounding tissue material properties were varied using Latin hypercube sampling to perform a sensitivity analysis. As in Part 1, urethral length, proximal and distal swinging, and shape parameters were measured at peak Valsalva for 50 simulations, and partial rank correlation coefficients were calculated between all model inputs and outputs. Cumulative influence factors determined which tissue properties were meaningfully influential (≥ 0.5).

RESULTS

The material properties of the urethra, perineal membrane, bladder, and paraurethral connective tissues meaningfully influenced urethral motion, deformation, and shape. Reduction of the urethral stiffness and/or the perineal membrane soft constraint resulted in simulated urethral motions and shapes associated with stress urinary incontinence in Part 1.

CONCLUSIONS

The data from Parts 1 and 2 suggest that connective tissues guide the controlled swinging motion and deformation of the urethra needed for passive closure during Valsalva. The swinging and kinking quantified in Part 1 and simulated in Part 2 are inconsistent with current continence theories.

Pelvic floor tissue damping during running using an intra-vaginal accelerometry approach

BACKGROUND

While cumulative loading of the pelvic floor during exercise appears to increase the risk of developing pelvic floor disorders, the pathophysiologic role of pelvic floor loading is poorly understood. The aim of this exploratory study was to present a method for evaluating vibrational frequency damping of the female pelvic floor and to investigate the potential utility of this approach in a preliminary evaluation.

METHODS

Female participants were instrumented with an intravaginal accelerometer and a hip-mounted accelerometer, then ran on a treadmill at 7 km/h and 10 km/h both before and after a 30-min self-selected pace. Displacement of the pelvic floor relative to the bony pelvis was calculated using double integration of the accelerometer data. Vibrational damping coefficients were calculated using a wavelet-based approach to determine the effect of continence status, parity, running speed and time on vibrational damping.

FINDINGS

Seventeen women (n = 10 reported regularly leaking urine while exercising, while n = 7 reported not leaking) completed the running protocol. No differences in vibrational damping were detected between continent and incontinent women when all frequency bands were evaluated together, however significant effects of parity, time, running speed and continence status were found within specific frequency bands. Parous women demonstrated less damping in the 25-40 Hz band compared to nulliparae, damping in the 13-16 Hz band was lower after the 30-min run, and incontinent women demonstrated lower damping in the 4.5-5.5 Hz band than continent women when running at 7 km/h.

INTERPRETATION

Intra-vaginal vibrational damping may be useful in detecting biomechanical mechanisms associated with pelvic floor disorders experienced by females during exercise.

Stress urinary incontinence is caused predominantly by urethral support failure

Whales are mammals that can dive to depths of > 1000 m without the high water pressure pushing open their mouth or anus. The same is true for the female urethra. The meatus externus and internus are seals that cannot be pushed open by high water pressures. Recent evidence suggests that the female meatus internus is pushed open when the bladder pressure exceeds the urethral pressure. For a relaxed detrusor, this opening is not possible for at least three reasons: the law of elastic collision, Pascal’s law of hydrostatics and the Hagen-Poiseuille law. The three laws do not support that urethral function failure is the predominant cause of stress urinary incontinence (SUI); however, they do support that urethral support failure is. Influential urogynecologists claim the opposite. TVT surgery, according to the integral theory of SUI (IT), has high failure rates because it does not principally prevent the urethra from hanging on a less mobile bladder neck. In the case of a long urethra, the tape is set too distally, and in hypomobile SUI, the use of a tension-free suburethral tape is unwarranted/ineffective, because the proximal urethra is not elevated above its resting position. A successful operation corrects urethral support failure and not urethral function failure.

Dimethyl fumarate ameliorates stress urinary incontinence by reversing ECM remodeling via the Nrf2-TGF-β1/Smad3 pathway in mice

INTRODUCTION AND HYPOTHESIS

Mechanical trauma and oxidative injury are involved in the pathogenesis of stress urinary incontinence (SUI), and oxidative stress (OS) is considered a potential therapeutic target. The antioxidant properties of dimethyl fumarate (DMF), a potent activator of Nrf2, have been highlighted recently. We therefore predicted that DMF might have therapeutic effects on mechanical trauma-induced SUI.

METHODS

The SUI mice model was established by vaginal distension (VD). Leak point pressure (LPP), serum OS biomarkers, cell proliferation and apoptosis, collagen, elastin, matrix metalloproteinases (MMP), Nrf2, the TGF-β1/Smad3 signaling pathway, and the associated tissue growth factors in the anterior vaginal wall were measured in either wild-type or Nrf2-knockout (Nrf2^-/^-) female C57BL/6 mice.

RESULTS

The results showed that DMF improved the VD-induced LPP reduction, alleviated oxidative injury, stimulated cell proliferation and inhibited apoptosis in the anterior vaginal wall tissue of mice. Moreover, DMF treatment reduced the hydrolysis of ECM proteins by MMP2 and MMP9. The above effects may be mediated by a series of tissue growth factors, including α-SMA, PAI-1, and TIMP-2, with the TGF-β1/Smad3 signaling pathway as the core regulatory mechanism. In further study, Nrf2^-/^- mice were used to replicate the SUI model. And the difference is that DMF failed to reactivate the TGF-β1/Smad3 pathway, nor did it improve LPP.

CONCLUSIONS

Dimethyl fumarate can ameliorate urethra closure dysfunction in the VD-induced SUI mice model, and the therapeutic effect of DMF is mediated by the Nrf2-dominated antioxidant system and its downstream TGF-β1/Smad3 signaling pathway.

Geometric analysis of the urethral-vaginal interface curvature in women with and without stress urinary incontinence: A pilot magnetic resonance imaging study

AIMS

To evaluate differences in the curvature of the urethral-vaginal interface in women with and without stress urinary incontinence (SUI) using geometric morphometric analysis techniques.

METHODS

We conducted a pilot case-control study using magnetic resonance imaging (MRI) scans of 18 women with and without SUI. The urethral-vaginal interface at the level of the mid-urethra was fitted with a second-order polynomial regression. The chord length and chord-to-vertex length of the resulting parabolic curve were used to calculate the arc length and radius of a circular arc fitted to the interface curvature. Demographic characteristics and Pelvic Organ Prolapse Quantification (POP-Q) parameters were collected. Subjects were stratified by those with and without SUI, as well as by those with and without anterior wall prolapse beyond 2 cm proximal to the hymen (Aa > -2 cm).

RESULTS

The radius of the urethral-vaginal interface curvature was not found to be different between subjects with and without SUI (8.8 vs. 9.2 mm, p = 0.53); however, this value was smaller in subjects with Aa > -2 (8.4 vs. 11.9 mm, p = 0.03). The chord length, chord-to-vertex length, and arc length comprising the urethral-vaginal interface curvature were similar between subjects with and without SUI, and between subjects with and without Aa > -2 cm (p > 0.05 for all).

CONCLUSIONS

In this pilot study population, the radius of the urethral-vaginal interface curvature at the mid-urethra was smaller among women with anterior vaginal wall prolapse beyond 2 cm proximal to the hymen. A difference in the urethral-vaginal interface curvature among women with and without SUI was not found.

Denonvilliers’ fascia acts as the fulcrum and hammock for continence after radical prostatectomy

Background

Radical prostatectomy (RP) is the primary treatment of localized prostate cancer. Immediate urinary incontinence post-RP was still common and depressing without specific reason.

Methods

A multicenter cohort of 154 consecutive patients from 2018 to 2020, who was diagnosed with localized prostate cancer underwent either modified mini-incision retropubic radical prostatectomy (Mmi-RRP) or laparoscopic radical prostatectomy (LRP) or robotic-assisted radical prostatectomy (RARP). Seventy-two patients with Denonvilliers’ fascia (DF) spared were included in DFS (Denonvilliers’ fascia sparing) group. Whereas eighty-two patients with DF completely or partially dissected were set as Group Control. The primary outcome was immediate continence (ImC). Continuous data and categorical data were analyzed with t-test and Chi-square test, respectively. Odds ratios (ORs) were calculated with logistic regression.

Results

Urinary continence of Group DFS was significantly better than that of Group Control at each time point within one year after operation. Incidence rate of continence in Group DFS and Group Control were 83.3% vs 13.4% (P < 0.01) for ImC, 90.3% vs 30.5% (P < 0.01) at 3 months, 91.7% vs 64.6% (P < 0.01) at 6 months, and 93.1% vs 80.5% (P = 0.02) at 1 year after operation, respectively. Positive surgical margin (PSM) showed no significant difference (20.8% vs 20.7%, P = 1.0). In multivariate analysis, DFS showed importance for ImC post RP (OR = 26.4, P < 0.01).

Conclusions

Denonvilliers’ fascia acted as the fulcrum and hammock for continence post RP. Preservation of DF contributed to better continence after RP without increase of PSM.

Trail registration Our research was conducted retrospectively and approved by the ethical committees of Minhang Hospital, but not registered.

Tacks vs. sutures: a biomechanical analysis of sacral bony fixation methods for laparoscopic apical fixations in the porcine model

Purpose

There is a novel surgical procedure, called cervicosacropexy (CESA) and vaginosacropexy (VASA) to treat pelvic organ prolapse and a concomitant urgency and mixed urinary incontinence. As there is little experience with the tapes so far and literature is scanty, the aim of this study was to investigate biomechanical properties for the fixation of the PVDF-tapes with three different fixation methods in context of apical fixations.

Methods

Evaluation was performed on porcine, fresh cadaver sacral spines. A total of 40 trials, divided into 4 subgroups, was performed on the anterior longitudinal ligament. Recorded biomechanical properties were displacement at failure, maximum load and stiffness in terms of the primary endpoints. The failure mode was a secondary endpoint. Group 4 was a reference group to compare single sutures on porcine tissue with those on human tissue. Biomechanical parameters for single sutures on the human anterior longitudinal ligament were evaluated in a previous work by Hachenberg et al.

Results

The maximum load for group 1 (two single sutures) was 65 ± 12 N, for group 2 (three titanium tacks arranged in a row) it was 25 ± 10 N and for group 3 (three titanium tacks arranged in a triangle) it was 38 ± 12 N. There was a significant difference between all three groups. The most common failure mode was a “mesh failure” in 9/10 trials for groups 1–3.

Conclusion

The PVDF-tape fixation with two single sutures endures 2.6 times more load than titanium tacks arranged in a row and 1.7 times more load than titanium tacks arranged in a triangle. The presacral fixation with titanium tacks reduced surgical time compared to the fixation with sutures, nevertheless sutures represent the significantly stronger and cheaper fixation method.

Urethral function and failure: A review of current knowledge of urethral closure mechanisms, how they vary, and how they are affected by life events

INTRODUCTION

A critical appraisal of the literature regarding female urethral function and dysfunction is needed in light of recent evidence showing the urethra's role in causing stress and urge urinary incontinence.

METHODS

An evidence assessment was conducted using selected articles from the literature that contained mechanistic data on factors affecting urethral function and failure.

RESULTS

Maximal urethral closure pressure (MUCP) is 40% lower in stress urinary incontinence (SUI) than normal controls. Evidence from five women shows relatively equal contributions to MUCP from striated/smooth muscle, vascular-plexus, connective tissue. MUCP varies twofold in individuals of similar age and declines 15% per decade even in nulliparous women. Age explains 57% of the variance in MUCP. This parallels with striated/smooth muscle loss and reduced nerve density. Factors influencing pressure variation minute-to-minute and decade-to-decade are poorly understood. Connective tissue changes have not been investigated. MUCP in de novo SUI persisting 9-months postpartum is 25% less than in age and parity-matched controls. Longitudinal studies do not show significant changes in urethral function after vaginal birth suggesting that changes in urethral support from birth may unmask pre-existing sphincter weakness and precipitate SUI. Mechanisms of interaction between support injury, pre-existing urethral weakness, and neuropathy are unclear.

CONCLUSION

Urethral failure is the predominant cause of SUI and a contributing factor for UUI; potentially explaining why mixed symptoms predominate in epidemiological studies. Age-related striated muscle loss and differences between women of similar age are prominent features of poor urethral closure. Yet, connective tissue changes, vasculature function, and complex interactions among factors are poorly understood.

Transvaginal subfascial synthetic sling - "A novel technique" versus trans-obturator mid-urethral sling in female stress urinary incontinence: A comparative study

Background

To assess the treatment outcome and overall efficacy of the novel technique of a transvaginal subfascial synthetic sling (TVSS) in comparison to the standard trans-obturator tape (TOT-O) mid-urethral sling for female stress urinary incontinence (SUI).

Materials and methods

The study included 206 female SUI patients managed at our institution between March 2015 and December 2019. The patients were randomly distributed into 2 comparable groups (Group A as TOT-O and Group B as TVSS) with respect to age, trouble due to SUI assessed with respect to degree of incontinence (number of episodes and diapers used per day), and body mass index (≤40 kg/m²), with 100 patients in the TOT-O group as group A and 106 patients in TVSS as group B. Preoperative variables related to the number of incontinent episodes and diapers usage were equal in both groups. The procedure was done under spinal anesthesia and results were assessed in terms of improvement in SUI as the primary outcome, any sexual dysfunction, complications, and overall satisfaction as secondary outcomes.

Results

Symptomatic improvement after the procedure was seen in all patients with complete resolution of symptoms in 91 patients (91.%) in the TOT-O group (group A) versus 96 patients (90.56%) in the TVSS (group B). Postoperative complications included urinary retention in 6% versus 5.6%, increased day time urinary frequency in 8% versus 6.6%, urge incontinence in 4% versus 2.8%, and groin/thigh pain in 12% versus 0.9%, respectively. Mesh incision was done in 1 (1%) versus none (0%), and local mesh excision for mesh erosion in 2 (2%) versus 1 (0.9%) at 3 months after the procedure in the TOT-O group and the TVSS group, respectively. The p value and Chi-Square test with respect to the clinical profile and satisfaction with respect to complete resolution of symptoms was calculated using Open EPI software which were insignificant. Sexual function (SF) was assessed using the Brief Index of SF for Women questionnaire. All the patients were satisfied with respect to SF at 6 months of follow-up.

Conclusions

The TVSS as a novel technique for female SUI is less invasive, simpler to learn, with less postoperative pain with resolution of SUI, rapid recovery, and good personal satisfaction compared to the standard TOT-O in procedure.

Ultrasonography and clinical outcomes following anti-incontinence procedures (Solyx™ tape): a 3-year post-operative review

INTRODUCTION AND HYPOTHESIS

Our primary objective was to study objective and subjective outcomes of patients with urodynamic stress incontinence (USI) following Solyx™ at 3-year follow-up. Our secondary objective was to evaluate ultrasonographic tape and bladder neck position and mobility.

METHODS

Records of 88 women who received Solyx™ surgery between September 2015 and December 2017 were reviewed. Ultrasonographic sling evaluation was performed at 6 months and 3 years postoperatively. Primary outcomes were objective and subjective cure of stress incontinence, defined as no involuntary urine leakage during filling cystometry, 1-h pad test < 2 g and negative response to Urogenital Distress Inventory-6 Question 3.

RESULTS

Subjective and objective cure rates at 3 years were 85.2% and 87.5%, respectively, with no complications reported. QOL improvements were maintained. Bladder neck position and mobility had no significant change between 6-month and 3-year follow-up. Tape position demonstrated significant shifts in the y-axis at both rest and Valsalva and in the x-axis at Valsalva between 6 months and 3 years; overall mobility was unchanged. Percentile of sling location remained unchanged at 60.1%, as did percentage of urethral kinking (67.9%) achieved. Risk factors for failure were bladder neck hypomobility postoperatively and no urethral kinking postoperatively.

CONCLUSIONS

There was good sustained objective and subjective cure with improved QOL in women who underwent Solyx™ for USI at 3-year follow-up. Ultrasonographic evaluation showed a tape position shift upwards and backwards with unchanged tape and bladder neck mobility. Percentile of sling location and rates of dynamic kinking were maintained.

Correlation Between Hypertrophic Cervical Elongation and Pelvic Organ Prolapse

OBJECTIVES

The association between hypertrophic cervical elongation and pelvic organ prolapse (POP) has been observed, but causation has not been determined. This study assessed the relationship of POP with hypertrophic cervical elongation according to menopausal status and the pelvic compartment involved in prolapse.

METHODS

This retrospective single-center case-control study was conducted at Shengjing Hospital of China Medical University between January 2017 and May 2019. Transverse and anteroposterior diameter of the cervix and cervical length were obtained by manual intravaginal measurement for 508 patients with POP and 510 patients without POP. Data were analyzed based on POP compartment and menopausal status.

RESULTS

In the premenopausal group, there was a statistically significant difference in the proportion of patients with hypertrophic cervical elongation in the non-POP and POP groups (P < 0.05); However, among postmenopausal patients, there was no statistical significance between these groups (P > 0.05). Patients with apical compartment POP had a higher proportion of occurrence of hypertrophic cervical elongation than those with nonapical compartment POP (P < 0.05).

CONCLUSIONS

Hypertrophic cervical elongation in premenopausal patients is significantly associated with POP; in particular, there is a significant correlation between apical compartment POP and hypertrophic cervical elongation.

The Female Pelvic Floor Fascia Anatomy: A Systematic Search and Review

The female pelvis is a complex anatomical region comprising the pelvic organs, muscles, neurovascular supplies, and fasciae. The anatomy of the pelvic floor and its fascial components are currently poorly described and misunderstood. This systematic search and review aimed to explore and summarize the current state of knowledge on the fascial anatomy of the pelvic floor in women. Methods: A systematic search was performed using Medline and Scopus databases. A synthesis of the findings with a critical appraisal was subsequently carried out. The risk of bias was assessed with the Anatomical Quality Assurance Tool. Results: A total of 39 articles, involving 1192 women, were included in the review. Although the perineal membrane, tendinous arch of pelvic fascia, pubourethral ligaments, rectovaginal fascia, and perineal body were the most frequently described structures, uncertainties were identified in micro- and macro-anatomy. The risk of bias was scored as low in 16 studies (41%), unclear in 3 studies (8%), and high in 20 studies (51%). Conclusions: This review provides the best available evidence on the female anatomy of the pelvic floor fasciae. Future studies should be conducted to clarify the discrepancies highlighted and accurately describe the pelvic floor fasciae.

Targeted neuromodulation of pelvic floor nerves in aging and multiparous rabbits improves continence

Pelvic floor muscle stretch injury during pregnancy and birth is associated with the incidence of stress urinary incontinence (SUI), a condition that affects 30-60% of the female population and is characterized by involuntary urine leakage during physical activity, further exacerbated by aging. Aging and multiparous rabbits suffer pelvic nerve and muscle damage, resulting in alterations in pelvic floor muscular contraction and low urethral pressure, resembling SUI. However, the extent of nerve injury is not fully understood. Here, we used electron microscopy analysis of pelvic and perineal nerves in multiparous rabbits to describe the extent of stretch nerve injury based on axon count, axon size, myelin-to-axon ratio, and elliptical ratio. Compared to young nulliparous controls, mid-age multiparous animals showed an increase in the density of unmyelinated axons and in myelin thickness in both nerves, albeit more significant in the bulbospongiosus nerve. This revealed a partial but sustained damage to these nerves, and the presence of some regenerated axons. Additionally, we tested whether electrical stimulation of the bulbospongiosus nerve would induce muscle contraction and urethral closure. Using a miniature wireless stimulator implanted on this perineal nerve in young nulliparous and middle age multiparous female rabbits, we confirmed that these partially damaged nerves can be acutely depolarized, either at low (2-5 Hz) or medium (10-20 Hz) frequencies, to induce a proportional increase in urethral pressure. Evaluation of micturition volume in the mid-age multiparous animals after perineal nerve stimulation, effectively reversed a baseline deficit, increasing it 2-fold (p = 0.02). These results support the notion that selective neuromodulation of pelvic floor muscles might serve as a potential treatment for SUI.

Impact of intrinsic sphincter deficiency on mid-urethral sling outcomes

INTRODUCTION AND HYPOTHESIS

Our primary objective was to study outcomes of patients with intrinsic sphincter deficiency (ISD) following mid-urethral slings (MUS) at 1-year. Our secondary objective was to delineate factors affecting success in these patients.

METHODS

Six hundred eighty-eight patients who had MUS between January 2004 and April 2017 were reviewed retrospectively; 48 women were preoperatively diagnosed with ISD. All completed urodynamic studies and validated quality-of-life (QOL) questionnaires at baseline and 1 year. Primary outcomes were objective and subjective cure of stress incontinence, defined as no involuntary urine leakage during filling cystometry and 1-h pad test < 2 g and negative response to Urogenital Distress Inventory-6 Question 3. Ultrasound was performed to determine tape position, urethral mobility and kinking at 1 year.

RESULTS

Women with ISD had significantly lower objective and subjective cure rates of 52.1% and 47.9%, respectively, compared to an overall of 88.2% and 85.9%. QOL scores significantly improved in those with successful surgeries. The sling type did not make a difference. Multivariate logistic regression identified reduced urethral mobility [OR 2.11 (1.24-3.75)], lower maximum urethral closure pressure (MUCP) [OR 1.61 (1.05-3.41)] and tape position [OR 3.12 (1.41-8.71)] to be associated with higher odds of failed slings for women with ISD.

CONCLUSIONS

Although there are good overall success in women undergoing MUS, those with ISD have significantly lower cure rates at 1 year. Factors related to failure include reduced urethral mobility, low MUCP and relative tape position further away from the bladder neck. Optimal management of patients with ISD and reduced urethral mobility remains challenging.

Urethral support in female urinary continence part 1: dynamic measurements of urethral shape and motion

INTRODUCTION AND HYPOTHESIS

Urethral closure mechanism dysfunction in female stress urinary incontinence (SUI) is poorly understood. We aimed to quantify these mechanisms through changes in urethral shape and position during squeeze (voluntary closure) and Valsalva (passive closure) via endovaginal ultrasound in women with varying SUI severity.

METHODS

In this prospective cohort study, 76 women who presented to our tertiary center for urodynamic testing as preoperative assessment were recruited. Urodynamics were performed according to International Continence Society criteria. Urethral pressures were obtained during serial Valsalva maneuvers. Urethral lengths, thicknesses, and angles were measured in the midsagittal plane via dynamic anterior compartment ultrasound. Statistical shape modeling was carried out by a principal component analysis on aligned urethra shapes.

RESULTS

Age, parity, and BMI did not vary by SUI group. Ultrasound detected a larger retropubic angle, urethral knee-pubic bone angle (a novel measure developed for this study), and infrapubic urethral length measurements at Valsalva in women with severe SUI (p = 0.016, 0.015, and 0.010). Shape analysis defined increased "c" shape concavity and distal wall pinching during squeeze and increased "s" shape concavity and distal wall thickening during Valsalva (p < 0.001). It also described significant urethral shape differences across SUI severity groups (p < 0.001).

CONCLUSIONS

Dynamic endovaginal ultrasound can visualize and allow for quantification of voluntary and passive urethral closure and variations with SUI severity. In women with severe SUI, excessive bladder neck and distal urethra swinging during Valsalva longitudinally compressed the urethra, resulting in a proportionally thicker wall at the mid-urethra and urethral knee.

Correlations between severity of anterior vaginal wall prolapse and parameters of urethral pressure profile

OBJECTIVE

Previous studies have shown that anterior vaginal wall prolapse (AVWP) results in reduction of pressure in the proximal urethra. However, the effect of severity of AVWP on urethral pressure is controversial. This study aimed to evaluate parameters of the urethral pressure profile in different stages of AVWP.

MATERIALS AND METHODS

From 2016 to 2017, 286 consecutive patients with urogynecologic complaints who were referred to our urodynamic unit were enrolled in this study to analyze their urethral pressure profiles. Stages of AVWP were regrouped into three groups ranging from mild to severe stages (groups 1-3). Maximal urethral pressure, urethral closure pressure, functional urethral length, length of continence zone, as well as area of continence zone were compared among these three groups.

RESULTS

Distribution of age, parity, and menopausal women were significantly different among these three groups. Maximal urethral pressure (pressures for groups 1, 2, and 3 were 74.6∼75.9cmH2O, 69.7∼73.4cmH2O, and 58.3∼60.5cmH2O, respectively; all P<.05) and stress urethral closure pressure (pressures for groups 1, 2, and 3 were 69.3cmH2O, 62.3cmH2O, and 52.2cmH2O, respectively; all P<.05) gradually and significantly decreased, consistent with the severity of AVWP. However, the attenuated maximal urethral pressure and stress urethral closure pressure in accordance with severity did not show any significant difference after controlling for age, body mass index, parity, menopause, and stress urinary incontinence symptoms.

CONCLUSION

Our results showed that AVWP significantly attenuated urethral pressure. However, patient age, menopausal status, and number of parities seem to be more influential in compromising urethral function than just AVWP alone.

The Reliability of Pelvic Floor Muscle Bioelectrical Activity (sEMG) Assessment Using a Multi-Activity Measurement Protocol in Young Women

The aim of the study was to determine the between-trial and between-day reliability of the Glazer protocol and our multi-activity surface electromyography (sEMG) measurement protocol for pelvic floor muscle (PFM) evaluation. The bioelectrical activity of PFM was collected using an endovaginal electrode in 30 young, Caucasian, nulliparous women (age 22–27, 168.6 ± 5.1 cm, 57.1 ± 11.8 kg). The between-trial and between-day reliability of the original Glazer protocol and the new multi-activity sEMG protocol were assessed during the following phases: pre-baseline rest, phasic (flick) contractions, tonic contractions, endurance contraction, and post-baseline rest. The Glazer protocol was characterized by poor and moderate measurement reliability. The time-domain parameters for the rise and fall of the signal amplitude and median frequency showed poor between-trial and between-day reliability. The mean and peak amplitudes indicated mainly good between-trial and moderate between-days reliability. Our protocol showed moderate to excellent reliability of both time-domain and quantitative parameters of muscle recruitment. In our protocol, the frequency-domain parameters describing muscle fatigue demonstrated much higher reliability than in the case of the Glazer protocol. The most important information obtained in this study was the significant improvement of diagnostic validity in PFM bioelectrical activity evaluation. The higher reliability of our sEMG protocol compared to original Glazer protocol allowed us to suggest that protocol modifications and changes in sEMG signal processing methods were effective in the improvement of PFM assessment quality. The new parameters calculated from the sEMG signal proposed in our sEMG protocol allowed us to obtain additional clinically important information about PFM dysfunctions regarding specific deficits of muscle contraction such as decrease in muscle strength; endurance or coordination related to, e.g., stress urinary incontinence; or pelvic floor muscle imbalance after childbirth.

Modified Lefort partial colpocleisis

INTRODUCTION AND HYPOTHESIS

We present a surgical video that describes the technical considerations for performing a modified LeFort partial colpocleisis.

METHODS

Hydro-dissection with diluted pituitrin was performed before the creation of anterior and posterior mid-line incisions through which lateral flaps were created bilaterally to expose the bladder and rectum fascia. Several purse-string sutures were placed to push the bladder and rectum back to their normal positions and reinforce the fascia under the vaginal wall. After removing the excess part of the vaginal wall, the lateral margins were re-approximated to create lateral channels that were wide enough to fit one finger. Perineoplasty was then performed to reduce the length of the genital hiatus.

RESULTS

The procedure was performed in a 76-year-old woman with stage III vaginal vault prolapse (POP-Q C + 2), stage IV anterior prolapse (POP-Q Ba+5), stage II posterior prolapse (POP-Q Bp-1), and mild occult stress urinary incontinence. The patient recovered well postoperatively, without recurrent prolapse and/or stress incontinence during 6 months of follow-up.

CONCLUSIONS

Our modified technique used traditional suture methods to strengthen the bladder and rectum fascia, keeping most of the vaginal wall to create a solid longitudinal septum in the center of the vagina that supported the vaginal vault.

Evidence of Common Pathophysiology Between Stress and Urgency Urinary Incontinence in Women

BACKGROUND/AIM

Urinary incontinence in women is commonly categorized as stress urinary incontinence (SUI) and urgency urinary incontinence (UUI). SUI occurs due to an increased intra-abdominal pressure caused by an unstable anatomical outlet of the bladder and can be successfully treated surgically. UUI, a combination of a symptom (urgency to void) and urinary incontinence, is considered to be caused by a neurological dysfunction of the bladder. Current treatment options can reduce the feeling of urgency, but effects on restoration of continence are less impressive. However, surgery for pelvic organ prolapse reduction leads to cure UUI, indicating a critical role of pelvic anatomy in the etiology of UUI. We hypothesized that incontinence in patients with UUI is caused by an anatomical instability at the bladder outlet leading to incontinence even under minor physical stress exerted on the bladder base.

PATIENTS AND METHODS

Patients with UUI symptoms were asked to specify exactly when (in which body position) they involuntary lose urine after the feeling of urgency to void.

RESULTS

In total, 569 patients were evaluated between 2012 and 2020. Overall, 96% of the patients lost urine when they got up from a sitting position on their way to the toilet. Of the total study patients 3% lost urine already in the sitting position when they felt the urgency to void.

CONCLUSION

The current treatment options for UUI are based on the hypothesis that UUI is a neurological disorder. This study demonstrated that urinary incontinence in patients with UUI is dependent on an intact anatomical stability of the urethro-vesical junction under pressure. Therefore, treatment modalities should focus on the anatomical repair or support in that area.

Epidemiological Features of the Bladder Neck Rest Position and Mobility

The data concerning epidemiological determinants of the bladder neck (BN) mobility are scarce. The aim of the study was to determine epidemiological features and identify factors influencing BN position at rest and BN mobility in patients without pelvic organ prolapse (POP). Seven hundred and ninety-six patients that attended two outpatient clinics were enrolled in the study. Position and mobility of the BN were measured with the use of pelvic floor ultrasound. Demographic and functional factors that were hypothesized to influence BN mobility were assessed. Vaginal deliveries (VDs) and age ≥65 were associated with lower BN position at rest. Higher BN mobility was observed in women with stress urinary incontinence (SUI). In obese women, higher BN position and lower BN mobility was observed compared to non-obese women, and it was correlated with longer urethras in this group of patients. VDs and their number were associated with increased BN mobility, independently of body mass index (BMI). To conclude, obesity, VDs, and age are factors associated with changes in bladder neck position at rest and its mobility. Higher BMI correlates with restricted BN mobility, and, therefore, the incidence of SUI in obese patients is probably not connected to BN hypermobility.

Contasure-needleless single incision slings versus transobturator slings (TOT/TVT-O) for female patients with stress urinary incontinence: a systematic review and meta-analysis

Background

To assess the current evidence on the effectiveness and safety of Contasure-Needleless (C-NDL) versus transobturator slings (TOT/TVT-O) in the management of female stress urinary incontinence (SUI).

Methods

A comprehensive literature review of articles that investigated the efficacy and safety of C-NDL and TOT/TVT-O was performed based on studies published before June 2019 and retrieved from PubMed, Embase, CNKI and the Cochrane Library. Two reviewers searched the literature, independently extracted the data and evaluated the quality of the data according to the inclusion and exclusion criteria. A meta-analysis was performed by using Review Manager 5.3 software.

Results

Seven studies with 1188 SUI female patients without intrinsic sphincter deficiency (ISD) or mixed urinary incontinence were included. Our meta-analysis showed that the clinical efficacy of C-NDL is statistically non-inferior to that of TOT / TVT-O in terms of subjective cure rate [OR = 0.77, 95% confidence interval (CI) (0.53 to 1.10), p = 0.15] and objective cure rate [OR = 0.78, 95% CI (0.53 to 1.13), p = 0.19]. In addition, operating times were statistically shorter with C-NDL compared to TOT / TVT-O [mean difference (MD) = − 7.38, 95% CI (− 10.73 to − 4.04), p < 0.0001]. In terms of the postoperative visual analogue scale (VAS) and the incidence of postoperative pain, C-NDL has a greater advantage [MD = − 1.71, 95% CI (− 2.91 to − 0.50), p = 0.005]; [OR = 0.21, 95% CI (0.05 to 0.96), p = 0.04]. Complication rates were statistically similar between the groups, except for groin pain which was higher in TOT / TVT-O.

Conclusion

Our data suggest that C-NDL slings have similar short-term efficacy as TOT/TVT-O in curing SUI patients. Compared with TOT/TVT-O, C-NDL is associated with a shorter operative time, and the incidence of postoperative pain is decreased. Nevertheless, these findings should be further confirmed through large-volume, well-designed prospective randomized controlled trials (RCTs) with long-term follow-up.

CACNA1H downregulation induces skeletal muscle atrophy involving endoplasmic reticulum stress activation and autophagy flux blockade

Multiple vaginal delivery (MVD) is an important factor for pelvic floor muscle (PFM) function decline and pelvic floor dysfunction (PFD). PFD is common in middle-aged and elderly women, but its pathogenesis is not clear. In this study, we found that the expression of CACNA1H was lower in the PFM of old mice after MVD compared with old or adult mice. In in-vitro studies, we found that treatment with the T-type Ca²⁺ channel (T-channel) inhibitor NNC-55 or downregulation of the CACNA1H gene by siRNA intervention promoted myotube atrophy and apoptosis. Mechanistically, we revealed that NNC-55 increased the expression of GRP78 and DDIT3 in myotubes, indicating endoplasmic reticulum stress (ERS) activation, and that the IRE1 and PERK pathways might be involved in this effect. NNC-55 induced the formation of autophagosomes but inhibited autophagy flux. Moreover, rapamycin, an autophagy activator, did not rescue myotube atrophy or apoptosis induced by NNC-55, and the autophagy inhibitors 3-MA and HCQ accelerated this damage. Further studies showed that the ERS inhibitors 4-PBA and TUDAC relieved NNC-55-induced damage and autophagy flux blockade. Finally, we found multisite muscle atrophy and decreased muscle function in Cacna1h^−/− (TH-null) mice, as well as increased autophagy inhibition and apoptotic signals in the PFM of old WT mice after MVD and TH-null mice. Taken together, our results suggest that MVD-associated PFD is partially attributed to CACNA1H downregulation-induced PFM atrophy and that ERS is a potential therapeutic target for this disease.

Dual-sectored transurethral ultrasound for thermal treatment of stress urinary incontinence: in silico studies in 3D anatomical models

The purpose of this study is to investigate the feasibility and performance of a stationary, non-focused dual-sectored tubular transurethral ultrasound applicator for thermal exposure of tissue regions adjacent to the urethra for treatment of stress urinary incontinence (SUI) through acoustic and biothermal simulations on 3D anatomical models. Parametric studies in a generalized tissue model over dual-sectored ultrasound applicator configurations (acoustic surface intensities, lateral active acoustic output sector angles, and durations) were performed. Selected configurations and delivery strategies were applied on 3D pelvic anatomical models. Temperature and thermal dose distributions on the target region and surrounding tissues were calculated. Endovaginal cooling was explored as a strategy to mitigate vaginal heating. The 75-90° dual-sectored transurethral tubular transducer (3.5 mm outer diameter (OD), 14 mm length, 6.5 MHz, 8.8-10.2 W/cm²) and 2-3-min sonication duration were selected from the parametric study for acoustic and biothermal simulations on anatomical models. The transurethral applicator with two opposing 75-90° active lateral tubular sectors can create two heated volumes for a total of up to 1.8 cm³ over 60 EM_43 °C, with at least 10 mm radial penetration depth, 1.2 mm urethral sparing, and no lethal damage to the vagina and adjacent bone (< 60 EM_43 °C). Endovaginal cooling can be applied to further reduce the vaginal wall exposure (< 15 EM_43 °C). Simulations on 3D anatomical models indicate that dual-sectored transurethral ultrasound applicators can selectively heat pelvic floor tissue lateral to the mid-urethra in short treatment durations, without damaging adjacent vaginal and bone tissues, as a potential alternative treatment option for stress urinary incontinence. Graphical abstract Schema for in silico investigation of transurethral ultrasound thermal therapy applicator for minimally invasive treatment of SUI.

The mysteries of menopause and urogynecologic health: clinical and scientific gaps

OBJECTIVES

A significant body of knowledge implicates menopausal estrogen levels in the pathogenesis of the common pelvic floor disorders (PFDs). These health conditions substantially decrease quality of life, increase depression, social isolation, caregiver burden, and economic costs to the individuals and society.

METHODS

This review summarizes the epidemiology of the individual PFDs with particular attention to the understanding of the relationship between each PFD and menopausal estrogen levels, and the gaps in science and clinical care that affect menopausal women. In addition, we review the epidemiology of recurrent urinary tract infection (rUTI)-a condition experienced frequently and disproportionately by menopausal women and hypothesized to be potentiated by menopausal estrogen levels.

RESULTS

The abundance of estrogen receptors in the urogenital tract explains why the natural reduction of endogenous estrogen, the hallmark of menopause, can cause or potentiate PFDs and rUTIs. A substantial body of epidemiological literature suggests an association between menopause, and PFDs and rUTIs; however, the ability to separate this association from age and other comorbid conditions makes it difficult to draw definitive conclusions on the role of menopause alone in the development and/or progression of PFDs. Similarly, the causative link between the decline in endogenous estrogen levels and the pathogenesis of PFDs and rUTIs has not been well-established.

CONCLUSIONS

Innovative human studies, focused on the independent effects of menopausal estrogen levels, uncoupled from tissue and cellular senescence, are needed.

Comparison of Solifenacin and Bilateral Apical Fixation in the Treatment of Mixed and Urgency Urinary Incontinence in Women: URGE 1 Study, A Randomized Clinical Trial

BACKGROUND

The aetiology of urgency urinary incontinence is a matter of debate. Current treatment options are based on the hypothesis of a neurological disorder of bladder innervation. However, it has also been hypothesised that one main cause is the reduced function of the bladder-holding apparatus, that is, insufficient suspension of the vesico-urethral junction. This study compared the effects of surgical apical vaginal elevation with those of solifenacin on urgency urinary incontinence in women.

PATIENTS AND METHODS

Women with mixed and urgency urinary incontinence were randomised to either an established pharmacological arm (10 mg/day solifenacin) or the surgical arm (bilateral uterosacral ligament replacement, cervicosacropexy, CESA; or vaginosacropexy, VASA. Clinical and objective outcomes were assessed at 4 months after each type of intervention.

RESULTS

The study was terminated early; 55 patients were operated on and 41 patients received pharmacological treatment. After surgical treatment, 23 patients (42%, 95% confidence intervaI=29-55%) became continent compared to four patients (10%, 95% confidence intervaI=1-19%) during solifenacin treatment.

CONCLUSION

Compared to pharmacological treatment, the surgical repair of the apical vaginal end restored urinary continence in significantly more patients.

Posterior pelvic tilt is a risk factor for rectal prolapse: a propensity score matching analysis

BACKGROUND

There is little evidence about possible effects of pelvic anatomical characteristics on proctological complications. The aim of our study was to investigate the potential correlation between sagittal pelvic position and rectal prolapse.

METHODS

A study was conducted on a proctology patients and patients without any specific history of proctological disorders who were divided into two groups according to the presence or the absence of rectal prolapse. In all cases, the pelvic angle was measured with a pelvic goniometer and categorized as posterior (< 10°), neutral (10°-15°), and anterior (> 15°). To minimize effects of potential confounders in the analysis, 3:1 nearest neighbor propensity score matching (PSM) method was implemented using age, sex, and diagnose of rectal disorders as confounding variables.

RESULTS

Among the 143 screened patients, posterior tilt was more frequent in the 19 patients with rectal prolapse than in those without prolapse (42 vs. 18%; p = 0.027). This result was also confirmed in the post-PSM analysis (42 vs. 14%; p = 0.036) using 35 propensity score (PS)-matched controls compared with the rectal prolapse group. Posterior tilt was associated with an increased risk of prolapse in both the unmatched population (odds ratio = 3.37; p = 0.020) and PS-matched subset (odds ratio = 4.36; p = 0.028).

CONCLUSIONS

A posterior pelvic angle was more frequently associated with the diagnosis of rectal prolapse. In both the entire population and in the PS-matched subset, posterior tilt was a significant risk factor for rectal prolapse. The easy-to-do investigation of the pelvic angle can provide several benefits in terms of rectal prolapse prevention and more precise management of post-surgical prolapse recurrence.

MR defecography in the assessment of anatomic and functional abnormalities in stress urinary incontinence before and after pelvic reconstruction

PURPOSE

Magnetic resonance defecography (MRD) was used to evaluate anatomic and functional pelvic floor disorders in women with stress urinary incontinence (SUI) before and after midurethral sling (MUS) intervention.

METHOD

We performed MRD in both SUI patients and continent controls. Static MR was used to describe the anatomic abnormalities in levator ani muscle and periurethral ligaments (PUL). Dynamic MR was used to depict the function of the urethra and pelvic floor. We compared the MRD parameters between the SUI patients and continent controls before surgery. For SUI patients, dynamic MR images evaluated the functional changes of the urethra and pelvic floor after surgery.

RESULTS

In SUI group, 75.8 % have PUL defects, 65.7 % discontinuity or complete loss of pubococcygeal muscle, as compared to the continent groups (p < 0.01). There was no significant difference between the perimenopausal volunteers and SUI patients in the puborectalis defection (p > 0.05). The dynamic MR showed the urethral hypermobility, functional urethra shortening, bladder neck funneling, urethra opening and cystocele were significantly associated with SUI patients (p < 0.01). Postoperative MR indicated that SUI patients after MUS had a lower risk of bladder funneling and urethral opening at the defection phase (p < 0.01), but no significant difference in urethral hypermobility or pelvic floor prolapse was seen (p>0.05).

CONCLUSIONS

MRD with high-resolution and defecation phases provides a detailed anatomic and functional evaluation of the pelvic floor in female SUI before and after pelvic reconstruction.

Involuntary cough is superior to voluntary cough for identifying stress urinary incontinence

Introduction

Voluntary cough (VC) and the laryngeal expiration reflex (LER) provoke stress urinary incontinence (SUI). The aim of this article is to analyze the effectiveness of these stimuli on the timing of urinary leaks.

Material and methods

Urodynamic testing using pressure catheters was performed on 123 subjects with history of SUI. The LER was triggered using the induced reflex cough test (iRCT). Each subject was tested with VC and LER and leaked with one or both stimuli. The occurrence and timing of leaks were recorded.

Results

The peak and average intra-abdominal pressures were 16-19% greater for LER compared to VC. Of the 123 subjects, LER caused leak in 118 (96%), VC in 71 (58%) and both in 66 (54%). For LER compared to VC, leak was more likely to occur during or immediately after the first expiratory effort. The electromyogram for VC and LER were similar.

Conclusions

The iRCT reliably initiated the LER and triggered SUI more effectively than VC. During VC, the smooth muscle of the internal urethral sphincter (IUS) starts to contract during inspiration, and constriction of the IUS continues into the expiratory phase; this increased urethral tonicity would lessen the likelihood of SUI. We refer to this as the inspiration closure reflex (ICR). With LER the inspiration would not take place, and the first expiratory effort would be against a non-constricted IUS, making leak more likely. Our findings disprove the pressure transmission theory. The internal and external urethral sphincters may both increase urethral closure pressure and resistance.

Stem cell therapy for stress urinary incontinence

Stress urinary incontinence is the involuntary loss of urine on effort or physical exertion. It is a highly prevalent condition affecting both men and women. Treatment is performed in a step-wise approach involving conservative measures, such as weight loss and pelvic floor exercises, medical treatment with duloxetine and a variety of surgical treatment options. However, recent restrictions in the use of synthetic mesh and tape have limited the surgical treatment options, leading to the need for new and novel treatment for stress urinary incontinence. Stem cell therapy is a developing medical field and offers the potential to restore normal physiological function of the urethral sphincter. The effectiveness of stem cell therapy in stress urinary incontinence has been demonstrated in pre-clinical studies, leading to its evaluation in several clinical studies. This review assesses the current evidence for the safety and efficacy of stem cell treatment for patients with stress urinary incontinence who have failed conservative and/or medical management and have not undergone previous surgical treatment for stress urinary incontinence.

Evidence Level: Not applicable

Normative values for Glazer Protocol in the evaluation of pelvic floor muscle bioelectrical activity

The aim of the study was to evaluate pelvic floor muscle bioelectrical activity in healthy, young, and nulliparous women, and to present normative values for all phases and parameters measured with the Glazer Protocol.In this study, 96 healthy, young, nulliparous women (age 22-27 years; 168.6 ± 5.1 cm; 57.1 ± 11.8 kg) were tested. The bioelectrical activity of the pelvic floor muscles was collected using an endovaginal electrode with the Glazer Protocol, which included the following series of muscles contractions and relaxations: pre-baseline rest, phasic contractions, tonic contractions, isometric contractions for muscle endurance evaluation, and post-baseline rest.The following normative values of the bioelectrical signal for all phases of the Glazer Protocol were calculated: mean, minimal, and maximal values, 95% confidence interval, standard deviation, 95% standard deviation confidence interval, variance, coefficient of variation, and standard error of measurement. Average Mean Amplitude (μV) was as follows: pre-baseline rest (6.26 ± 3.33 μV), phasic contractions (49.76 ± 26.44 μV), tonic contractions (37.05 ± 25.99 μV), endurance contraction (16.10 ± 6.68 μV), and post-baseline rest (6.93 ± 3.99 μV).This study was the first in which normative values for all phases of the Glazer Protocol were reported. This protocol is very often used in electromyography devices as a tool for pelvic floor muscle assessment. Due to the fact that the interpretation of the pelvic floor muscle evaluation is complex and difficult, the authors believe that the normative values proposed in this study allow for comprehensive interpretation of this test (both qualitatively and quantitatively) and provide a reference point for parameters measured in women with different pelvic floor dysfunctions.