In vivo assessment of the levator ani muscles using shear wave elastography: a feasibility study in women

Impact of sexual activity on bulbocavernosus muscle stiffness assessed by shear wave elastography in women

PURPOSE

The bulbocavernosus muscle (BCM) is a vital component of the pelvic floor muscles, significantly contributing to women's sexual function. Shear wave elastography (SWE) is an innovative, non-invasive imaging technique offering quantitative insights into tissue stiffness, yet its application in evaluating BCM stiffness remains unexplored. This study investigates the stiffness of the BCM in women with different sexual activity histories using SWE.

METHODS

This cross-sectional study was conducted at a tertiary hospital in China between April and September 2024. Sixty-two women aged 18 to 40 were assigned to two groups: the sexually active group (SAG) and the sexually inactive group (SIG). BCM stiffness was measured at rest and during maximal voluntary contraction (MVC). The correlations between BCM stiffness and the Female Sexual Function Index (FSFI) scores were also examined.

RESULTS

Women in the SAG exhibited significantly higher BCM stiffness during MVC compared to those in the SIG, and BCM stiffness during MVC was moderately correlated with the orgasm domain of the FSFI. There were no significant differences in BCM stiffness at rest between the two groups.

CONCLUSION

Sexual activity may positively influence BCM stiffness, which could lead to improved pelvic floor muscle function and potentially enhance sexual health. A moderate correlation between BCM stiffness during MVC and the orgasm domain of the FSFI, suggesting a possible biomechanical association between BCM function and sexual function. Further research is needed to confirm this relationship and explore its clinical implications.

Assessment of pelvic floor dysfunction after total hysterectomy: A preliminary study based on transperineal ultrasound and shear wave elastography

OBJECTIVE

To investigate the application of transperineal ultrasound (TPUS) and shear wave elastography (SWE) in the assessment of pelvic floor dysfunction (PFD) after total hysterectomy and to explore associated imaging indicators.

METHODS

Forty-seven women who underwent total hysterectomy and 70 healthy women were prospectively enrolled in our study. We recorded relevant clinical information, including age, body mass index (BMI), and obstetric history. All participants underwent TPUS and SWE examination at rest, during contraction, and during the maximum Valsalva maneuver. The intra- and inter-observer repeatability of SWE measurements was assessed. And the comparison of the imaging parameters between the two groups was conducted. Further receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficacy of TPUS and SWE in predicting PFD.

RESULTS

SWE used in this study to quantify LAM elasticity demonstrated satisfactory repeatability with all ICC values higher than 0.75. The incidence of PFD was significantly higher in the case group compared to the control group (57.45 % vs. 38.57 %, P = 0.045). The sagittal hiatal diameter (SHD) was higher while the thickness of the levator ani muscle (LAM) was lower in the case group compared to the normal group (P < 0.05), and the SHD showed a positive correlation with PFD while LAM showed a negative correlation. The elastic modulus values of Emax and Emean were significantly increased during contraction in the case group (P = 0.011 and P = 0.029). Further ROC analysis showed that TPUS alone and the combination of TPUS with SWE were both effective in diagnosing PFD than SWE alone (AUC = 0.946, 0.971 and 0.642 respectively).

CONCLUSION

Our research highlights the significance of the visual assessment of PFD using TPUS and SWE. A widened SHD, a thinned LAM and decreased compliance of LAM during contraction may be correlated with increased PFD.

Perineal body and anal sphincter biometrics and stiffness using elastography during labor: a feasibility study

OBJECTIVES

The study aimed to evaluate the biometrics and stiffness of the perineal body and anal sphincter using 2D-mode ultrasound and shear wave elastography (SWE) during labor and to assess their association with perineal tears.

METHODS

A prospective observational study was conducted on pregnant women. The perineal body (PB), the external anal sphincter (EAS), the internal anal sphincter (IAS) and the anal mucosa (AM) biometrics and stiffness were measured during labor using a transperineal 2D-mode ultrasound and shear wave elastography (SWE), respectively, at rest and during Valsalva maneuvers.

RESULTS

Among the 10 women who underwent a vaginal delivery, 6 (60.0 %) perineal tears occurred. All were first degree perineal tears. Before expulsive efforts, the PB area at rest was statistically higher in women with perineal tears (1.0 ± 0.1 cm2 vs 0.3 ± 0.1 cm2, p < 0.01). The perineal body length, height and area seemed to decrease between the onset of labor and the beginning of expulsive efforts. The PB Youngs' modulus at rest at the onset of labor or before expulsive efforts were 11.9 ± 3.6 kPa and 25.7 ± 18.9 kPa, respectively. The PB elastic modulus at rest and at the onset of labor (11.3 ± 4.1 vs 12.9 ± 2.9 kPa, p = 0.6) or before expulsive efforts (18.0 ± 15.9 vs 37.4 ± 18.6 kPa, p = 0.1) tended to be higher in women with a perineal tear at delivery, but it was not statistically significant.

CONCLUSION

In vivo assessment of both the perineal body and anal sphincter biometrics and stiffness during labor in women is feasible. The perineal body area during labor could be a predictive factor for perineal tears, suggesting a potential link between its stiffness and tear risk.

TRIAL REGISTRATION

The study was registered on https://clinicaltrials.gov (NCT05556304): https://classic.

CLINICALTRIALS

gov/ct2/show/NCT05556304.

The application of transperineal ultrasonography combined with shear wave elastography in the evaluation and monitoring of pelvic floor function in the early stage after total hysterectomy

BACKGROUND

To investigate the combined effect of transperineal ultrasound and Shear Wave Elastography (SWE) in the evaluation and monitoring of pelvic floor functions after total hysterectomy.

METHODS

Fifty-two women who planned to undergo total hysterectomy from January 2019 to December 2022 in Nantong Third People's Hospital were selected, and the pelvic floor functions were assessed using transperineal ultrasound combined with SWE. The dynamic alterations in pelvic floor functions at different time points were compared after hysterectomy. The differences in pelvic floor parameters were compared between Transabdominal Total Hysterectomy (TAH) and Laparoscopic Total Hysterectomy (LTH).

RESULTS

The Posterior Urethravesical Angle at rest and Valsalve maneuver (R-PUA, V-PUA), antero-posterior diameter of the hiatus at rest and Valsalve maneuver (R-HAPD, V-HAPD), and elastic modulus of left and right puborectalis at rest (R-L-PRE, R-R-PRE), the Urethral Rotation Angle (URA)were obviously higher at 3 mon after surgery than before surgery and at 1-mon after surgery; the bladder neck-symphyseal distance at rest and Valsalve maneuver (R-BSD,V-BSD), and the difference in elasticity between the left and right puborectalis muscles (L-∆E, R-∆E) were markedly lower at 3 mon than before surgery and at 1 mon after surgery; V-BSD, L-∆E, R-∆E were obviously decreased and the Bladder Neck Descen (BND), URA, V-PUA were obviously increased in the TAH group in comparison with the LTH group.

CONCLUSION

Pelvic floor functions start to be weak at 3 months after total hysterectomy. TAH causes more significant damage to the structures and functions of the pelvic floor.

Exploring the influence of perineal biometrics and stiffness measured by elastography during pregnancy on perineal tears : A pilot study

OBJECTIVES

This study aimed to describe the biometrics and elasticity of the perineal body and the anal sphincter in the ninth month of pregnancy and explore their association with the risk of perineal tears during childbirth.

METHODS

In this prospective observational study, pregnant women at 36-40 weeks of gestation were included. Using transperineal 2D-mode ultrasound and shear wave elastography (SWE), we measured the biometrics and stiffness of the perineal body (PB), external anal sphincter (EAS), internal anal sphincter (IAS), and anal mucosa (AM) at rest and during Valsalva maneuvers.

RESULTS

Of the 16 women, five (31.2 %) were nulliparous and 10 (62.5 %) underwent a perineal tear. All were first degree perineal tears. Women with perineal tear had statistically a higher perineal body area at rest (0.9 ± 0.1 cm² versus 0.7 ± 0.1 cm², p = 0.03), a thicker EAS at 9 o'clock at rest (0.6 ± 0.2 cm vs 0.4 ± 0.1 cm, p = 0.03), a smaller anteroposterior diameter (1.7 ± 0.2 cm vs 2 ± 0.2 cm, p = 0.047), a smaller lateral diameter (1.4 ± 0.2 cm vs 1.6 ± 0.1 cm, p = 0.05) and a thinner IAS in average at rest (0.2 ± 0.0 cm vs 0.3 ± 0.0 cm, p = 0.007) and at 12 o'clock at rest (0.2 ± 0.1 cm vs 0.3 ± 0.0 cm, p = 0.002). The PB, EAS, IAS and AM elastic modulus in the ninth month of pregnancy tended to be higher in women with a perineal tear.

CONCLUSION

Assessing perineal and anal sphincter biometrics and stiffness via ultrasound and SWE is feasible and may indicate a risk of perineal tears.

TRIAL REGISTRATION

The study was registered on (NCT05556304).

In vivo measurement of the elastic properties of pelvic floor muscles in pregnancy using shear wave elastography

OBJECTIVE

We aimed to investigate changes in the elastic properties of levator ani muscle (LAM) and external anal sphincter (EAS) during pregnancy using shear wave elastography (SWE). Our secondary objective was to examine the association between the elastic properties of pelvic floor muscles (PFM) and perineal tears at childbirth.

METHODS

This was a prospective monocentric study, including nulliparous women. Three visits were planned (14-18, 24-28, and 34-38 weeks) with a SWE assessment of the LAM and EAS at rest and during Valsalva maneuver. Then, we collected data about the delivery's characteristics. Assessments were performed using an Aixplorer V12® device (SL 18-5 linear probe) using a transperineal approach, reporting the shear modulus in kPa. We looked for changes in PFM's elastic properties during pregnancy using one-way ANOVA for repeated measures. We compared the mean shear modulus in late pregnancy for each muscle and condition between women with an intact perineum at delivery and those with a perineal tear using Student's t test.

RESULTS

Forty-seven women were considered. Forty-five women had vaginal delivery of which 38 (84.4%) had perineal tears. We did not report any significant changes in the elastic properties of PFM during pregnancy. Women with an intact perineum at delivery had a stiffer EAS at Valsalva maneuver in late pregnancy (27.0 kPa vs. 18.2 kPa; p < 0.005).

CONCLUSIONS

There were no significant changes in the elastic properties of the PFM in pregnancy. Stiffer EAS in late pregnancy appears to be associated with a lower incidence of perineal tears.

Evaluation of levator ani muscle elasticity after vaginal delivery and cesarean section using shear wave elastography

PURPOSE

The risk of pelvic floor muscle injury is commonly considered to be higher in vaginal than in cesarean delivery. This study aimed to compare levator ani muscle (LAM) elasticity after vaginal and cesarean delivery using shear wave elastography (SWE).

METHODS

Postpartum women who underwent a single SWE evaluation 1 month after their first delivery were divided into vaginal and cesarean delivery groups. The elastic moduli of both sides of the LAM were measured in a horizontal section and compared between the groups. In addition, a subgroup analysis was performed to compare LAM elasticity according to the delivery method within the vaginal delivery group-normal vaginal delivery, episiotomy, and operative vaginal delivery.

RESULTS

Sixty-two women were included (vaginal delivery, n = 47; elective cesarean section, n = 15). Multiple regression analysis revealed that the LAM elastic modulus was significantly lower in the vaginal delivery group than in the cesarean delivery group (right LAM: 44.2 vs. 72.7 kPa, p = 0.0036; left LAM 40.4 vs. 82.7 kPa, p < 0.0001). In the subgroup analysis, the right LAM elastic modulus was significantly lower in the operative vaginal delivery subgroup than in the normal vaginal delivery subgroup (p = 0.0131). However, there was no significant difference in the left LAM elastic modulus between the three subgroups.

CONCLUSION

LAM elasticity was significantly lower after vaginal delivery than after cesarean delivery. Furthermore, the elasticity of the right LAM was lower after operative vaginal delivery than after normal vaginal delivery. SWE has the potential to provide an objective quantitative assessment of postpartum pelvic floor muscle recovery.

The Correlation between Transperineal Shear-Wave Elastography and Transabdominal Ultrasound When Assessing Pelvic Floor Function in Nulliparous Women

Pelvic floor muscles (PFMs) play a crucial role in maintaining pelvic organ support and continence. However, pelvic floor dysfunction (PFD), often resulting from insufficient PFM control, poses a substantial global health challenge for women. This study aims to explore the relationship between levator ani muscle elasticity when assessed through transperineal shear-wave elastography (SWE) and bladder base displacement, quantified using transabdominal ultrasonography (TAUS), as a means to comprehensively evaluate PFM function. A total of 42 nulliparous women participated in this study. Participants received instructions on proper PFM contractions using Kegel exercises. Levator ani muscle elasticity was assessed both at rest and during contractions using transperineal SWE, while bladder base displacement was simultaneously measured through TAUS. Repeated measures demonstrated strong intraclass correlation coefficients of 0.906 at rest and 0.687 during contractions for levator ani muscle elasticity. The mean elasticity values were 24.7 ± 4.5 kPa at rest and 62.1 ± 10.4 kPa during contractions. Additionally, the mean bladder base displacement was 7.2 ± 2.5 mm, and the normalized bladder base displacement via body mass index was 0.3 ± 0.1 mm. Significantly, a moderate correlation was identified between the PFM function, represented by the difference in levator ani elasticity during contractions and resting, and bladder base displacement (r = 0.486, p = 0.001). These findings underscore the potential utility of transperineal SWE as a reliable and noninvasive method to assess levator ani muscle elasticity and, consequently, PFM function. In conclusion, this study sheds light on the interplay between PFM elasticity and bladder base displacement, offering insights into PFM function assessments. The observed correlation suggests the clinical relevance of SWE in providing valuable information for treatment planning in PFD. These findings contribute to a deeper understanding of PFM dynamics, ultimately aiding in the effective management of PFD among women.

In vivo assessment of the elastic properties of the external anal sphincter in term pregnant women using shear wave elastography

INTRODUCTION AND HYPOTHESIS

The objective was to assess the intraobserver intersession and interobserver intrasession reliability of shear wave elastography applied to the external anal sphincter in term pregnant women.

METHODS

This prospective study involved nulliparous pregnant women at 37 weeks or more with two visits (V1: one observer; V2 two observers) planned within a 12-h to 7-day interval. Measurements were performed using an Aixplorer V12® device with an SL 18-5 linear probe using a transperineal approach, allowing a measurement of the shear modulus (SM) in kPa. Measures were performed at rest, Valsalva maneuver, and maximal contraction. Reliability was assessed using the intraclass correlation coefficient (ICC). The study was approved by an ethics committee (ID RCB: 2020-A00764-65).

RESULTS

A total of 37 women were included. Intraobserver reliability was excellent at rest (ICC = 0.91 [0.84-0.95) and good during the Valsalva maneuver (ICC = 0.83 [0.72-0.90]) and contraction (ICC = 0.85 [0.75-0.91]). Interobserver reliability was good at rest (ICC = 0.79 [0.66-0.87]) and during Valsalva (ICC = 0.84 [0.73-0.90]), but moderate during contraction (ICC = 0.70 [0.53-0.82]).

CONCLUSIONS

Shear wave elastography is a reliable tool for assessing the elastic properties of the external anal sphincter in term pregnant women.

Application of transperineal ultrasound combined with shear wave elastography in pelvic floor function assessment after hysterectomy

This study explored the application of transperineal ultrasound (TPUS) combined with shear wave elastography (SWE) in evaluating the pelvic structure function of women after total hysterectomy. Seventy healthy women and 76 women who underwent total hysterectomy were selected for ultrasound examination. They were divided into normal (nulliparous) group, (parous) group without hysterectomy, and (parous) group with hysterectomy. TPUS combined with SWE was used to evaluate the pelvic floor structure and function in the 3 groups of women. Posterior urethrovesical angle in resting and maximal Valsalva state, anteroposterior diameter of hiatus in the 3 states, the bladder neck descent, the urethral rotation angle, the Young modulus of left and right puborectalisis muscle in resting state, and the incidence of pelvic floor dysfunction diseases were all higher in the group with hysterectomy than in the group without hysterectomy (P < .05). Bladder neck-symphyseal distance and anorectal junction-symphyseal distance in the maximum Valsalva state, and the difference in Young modulus between the left and right PR before and after anus contraction were all lower in the group with hysterectomy than the group without hysterectomy (P < .05). The incidence of pelvic floor dysfunction in postmenopausal patients in the group with hysterectomy was higher than that in premenopausal patients (P < .05). Total hysterectomy had negative effects on female pelvic floor structure and function. TPUS combined with SWE can be used to evaluate pelvic floor function in multiple dimensions.

Validation of shear wave elastography as a noninvasive measure of pelvic floor muscle stiffness

OBJECTIVES

To investigate the validity of shear wave elastography (SWE) as a measure of stiffness of the puborectalis muscle by examining: (1) the relationship between puborectalis muscle stiffness and pelvic floor muscle (PFM) activation at different intensities; and (2) the relationship between puborectalis stiffness and pelvic floor morphometry during contractions at different intensities.

METHODS

Fifteen healthy asymptomatic women performed 6-s isometric PFM contractions at different intensities (0, 10%, 20%, 30%, 50%, 75%, and 100% of maximal voluntary contraction) guided by intravaginal electromyography (EMG). Stiffness of the puborectalis muscle was measured using SWE by calculating the average shear modulus in regions of interest that contained puborectalis muscle fibers parallel to the transducer. Pelvic floor morphometry was assessed in the mid-sagittal plane using transperineal B-mode ultrasound imaging. Shear modulus, EMG (root mean square amplitude) and pelvic floor morphometry parameters were normalized to the value recorded during maximal voluntary contraction. To assess the relationship between stiffness and pelvic floor activation/morphometry, coefficient of determination (r² ) was calculated for each participant and a group average was computed.

RESULTS

Shear modulus and EMG were highly correlated (average r² ; left 0.90 ± 0.08, right 0.87 ± 0.15). Shear modulus also strongly correlated with bladder neck position (x-axis horizontal coordinates relative to the pubic symphysis), anorectal rectal angle and position, levator plate angle, and antero-posterior diameter of the levator hiatus (average r² : range 0.62-0.78).

CONCLUSIONS

These findings support the validity of SWE to assess puborectalis muscle stiffness in females. Stiffness measures were strongly associated with PFM EMG and pelvic floor morphometry and may be used to indirectly assess the level of activation of the puborectalis muscle without the use of more invasive techniques. By overcoming limitations of current assessment tools, this promising noninvasive and real-time technique could enable important breakthrough in the pathophysiology and management of pelvic floor disorders.

Usefulness of transperineal shear wave elastography of levator ani muscle in women with stress urinary incontinence

This study aimed to quantitatively assess the quality of levator ani muscle (LAM) using shear wave elastography (SWE) and to evaluate the association between the elasticity of LAM and stress urinary incontinence (SUI). The study population included 32 women with SUI and 34 women with normal pelvic support. The thickness of LAM, bladder neck descent (BND), and urethral funneling (UF) were assessed by transperineal ultrasound. LAM elasticity was measured by SWE at rest and during the maximal Valsalva maneuver. Age, menopause, BND, and UF showed a positive correlation with SUI. There was no significant between-group difference in the elastic modulus values of LAM at rest. The thickness of LAM in women with SUI was greater than that in control group at rest and during the maximal Valsalva maneuver (P < 0.001). The elastic modulus values of Emax and Emean were significantly increased from rest to the maximal Valsalva maneuver in all participants (56.24 vs 82.43 kPa and 47.92 vs 72.37 kPa, P < 0.001). The change of these variables from rest to the maximal Valsalva maneuver in the control group was more obvious than that in the SUI group (34.09 vs 17.87 kPa and 31.55 vs 16.82 kPa, P < 0.05). The elasticity of LAM, as quantified by SWE, may potentially be used as an index for predicting SUI.

Simulation of the mobility of the pelvic system: influence of fascia between organs

The mobility of pelvic organs is the result of an equilibrium called Pelvic Static characterizing the balance between the properties and geometries of organs, suspensions and support system. Any imbalance in this complex system can cause of pelvic static disorder. Genital prolapse is a common hypermobility pathology which is complex, multi factorial and its surgical management has high rate of complications. The use of 3 D numerical models and simulation enables the role of the various suspension structures to be objectively studied and quantified. Fascias are connective tissues located between organs. Although their role are described as important in various descriptions of pelvic statics, their influence and role has never been quantitatively objectified. This article presents a refine Finite Element (FE) model for a better understanding of biomechanical contribution of inter-organ fascia. The model is built from MRI images of a young volunteer, the mechanical properties derived from literature data to take into account the age of the patient and new experimental results have enabled an order of magnitude of the mechanical properties of the fascias to be defined. The FE results allows to quantify the biomechanical role of the fascia on pelvic mobility quantified by an analysis of dynamic MRI images and a local mapping of the gap between calculated and measured displacements. This improved numerical model integrating the fascias makes it possible to describe pelvic mobilities with a gap of 1 mm between numerical simulations and measurements, whereas without taking them into account this gap locally reaches 20 mm.

Assessment of the Elastographic and Electromyographic of Pelvic Floor Muscles in Postmenopausal Women with Stress Urinary Incontinence Symptoms

Background. Shear wave elastography is an effective method for studying the condition of various musculoskeletal soft tissues. The primary aim of this study was the objective elastographic and electromyographic assessment of the pelvic floor during the rest and contraction of the pelvic floor muscles (PFM) in postmenopausal women. Methods. This was a prospective observational study that was carried out at the University Hospital in Wroclaw, Poland, between January 2017 and December 2019. Patients. The target group of the study included postmenopausal women with stress urinary incontinence. The primary outcomes were the features of the elastographic assessment of the pelvic floor during rest and contraction of the PFM obtained using shear wave elastography. Results. Based on the inclusion and exclusion criteria for the study, 14 patients took part in the measurements. There was a significant difference between the elastographic assessment of the pelvic floor during rest and contraction of the PFM at all locations in front of the urethra. No statistically significant correlation was found between the results of elastography and the bioelectrical activity of PFM. Conclusion. The elasticity of the periurethral structures is higher during active pelvic floor muscle contraction than at rest, it seems that shear wave elastography is an effective test that objectively assesses the strength of PFM contraction.

Transperineal ultrasound shear-wave elastography is a reliable tool for assessment of the elastic properties of the levator ani muscle in women

Our main objective was to assess the intraoperator intersession reproducibility of transperineal ultrasound Shear Wave Elastography (SWE) to measure the levator ani muscle (LAM) elastic properties. Secondary objective was to compare reproducibility when considering the mean of three consecutives measurements versus one. In this prospective study involving non-pregnant nulliparous women, two visits were planned, with a measurement of the shear modulus (SM) on the right LAM at rest, during Valsalva maneuver and maximal contraction. Assessments were done with a transperineal approach, using an AIXPLORER device with a linear SL 18–5 (5-18 MHz) probe. For each condition, 3 consecutive measures were performed at each visit. The mean of the three measures, then the first one, were considered for the reproducibility by calculating intraclass correlation coefficient (ICC), and coefficient of variation (CV). Twenty women were included. Reproducibility was excellent when considering the mean of the 3 measures at rest (ICC = 0.90; CV = 15.7%) and Valsalva maneuver (ICC = 0.94; CV = 10.6%), or the first of the three measures at rest (ICC = 0.87; CV = 18.6%) and Valsalva maneuver (ICC = 0.84; CV = 19.9%). Reproducibility was fair for measurement during contraction. Transperineal ultrasound SWE is a reliable tool to investigate LAM elastic properties at rest and during Valsalva maneuver.

Vaginal elasticity is significantly decreased in vaginal atrophy: a strain elastography study

OBJECTIVES

Strain elastography is a novel method to assess the elasticity of tissues. We aimed to evaluate the value of vaginal strain elastography in women with vulvovaginal atrophy (VVA).

METHODS

Women with or without VVA were enrolled in this prospective study. Participants underwent vaginal cytology and vaginal wall elastography. Vaginal Health Index (VHI) was calculated. Based on Vaginal Maturation Value (VMV), participants were divided into atrophic and nonatrophic groups. Elastography parameters of the vaginal walls were measured in nine regions of interest (ROI). Elastography Index (EI) was defined by the average color score of nine ROIs. Groups were compared with unpaired t test or Mann-Whitney U test. Pearson correlation was used to determine the strength of association between EI and selected parameters. Multiple regression was used to evaluate the association between EI and age, VMV, and vaginal atrophy.

RESULTS

Ten women were diagnosed with VVA, and twenty had no cytological signs of vaginal atrophy (age-range 38-79 y). VHI score was significantly lower in the atrophic group (mean ± SD, 9.4 ± 2.011 vs 16.6 ± 4.22, P < 0.0001). In the atrophic group, EI was significantly lower than in nonatrophic group (mean ± SD, 20 ± 21 vs 47 ± 4, P < 0.01). We found a strong negative correlation between EI and vaginal atrophy (r =  -0.706, P < 0.0001; 95% CI: 0.8501 to -0.4639). In the multiple regression model, only atrophy remained statistically significant for the prediction of EI (P = 0.004).

CONCLUSIONS

Vaginal elasticity is significantly decreased in women with vaginal atrophy, measured by EI. Our results suggest that strain elastography might be useful in the diagnosis of vaginal atrophy.

An International Continence Society (ICS) report on the terminology for pelvic floor muscle assessment

INTRODUCTION

The terminology for female and male pelvic floor muscle (PFM) assessment has expanded considerably since the first PFM function and dysfunction standardization of terminology document in 2005. New terms have entered assessment reports, and new investigations to measure PFM function and dysfunction have been developed. An update of this terminology was required to comprehensively document the terms and their definitions, and to describe the assessment method and interpretation of the finding, to standardize assessment procedures and aid diagnostic decision making.

METHODS

This report combines the input of members of the Standardisation Committee of the International Continence Society (ICS) Working Group 16, with contributions from recognized experts in the field and external referees. A logical, sequential, clinically directed assessment framework was created against which the assessment process was mapped. Within categories and subclassifications, each term was assigned a numeric coding. A transparent process of 12 rounds of full working group and external review was undertaken to exhaustively examine each definition, plus additional extensive internal development, with decision making by collective opinion (consensus).

RESULTS

A Terminology Report for the symptoms, signs, investigations, and diagnoses associated with PFM function and dysfunction, encompassing 185 separate definitions/descriptors, has been developed. It is clinically based with the most common assessment processes defined. Clarity and user-friendliness have been key aims to make it interpretable by clinicians and researchers of different disciplines.

CONCLUSION

A consensus-based Terminology Report for assessment of PFM function and dysfunction has been produced to aid clinical practice and be a stimulus for research.

Gender-specific differences of normative values of pelvic floor muscle function in healthy adults population: an observational analytical study

Females and males differ significantly in gross anatomy and physiology of the pelvic floor muscle, and these differences are commonly discussed in the scientific literature. However, less attention is dedicated to investigating the normative values of pelvic floor muscle (PFM) function between females and males. Our study aims to describe the normal reference values of PFM function in females and males of a healthy adult population using transabdominal ultrasound (TAUS). A total of 200 healthy adults, including 71 males and 129 females consented to participate in this study. Bladder base displacement was measured using a sagittal curved linear array 2-5 MHz transducer over the suprapubic region. The amount of bladder base movement on ultrasound was measured in all subjects from freeze frame ultrasound images and considered as an indicator of PFM function. The average age of subjects was (26.1 ± 2.6 years), (24.4 ± 3.7 BMI). Statistical analysis revealed a significant difference in transabdominal ultrasound measurement for PFM function (p = .00000). The bladder base displacement was significantly greater in males compared to females (0.65 ± 0.42 vs. 0.38 ± 0.35, p <.001, 95% CI:0.16-0.38). The present study provides evidence of a gender-related PFM functional differences creating a baseline for the clinic to establish the normal percentile values of PFM function.

Quantifying Levator Ani Muscle Elasticity Under Normal and Prolapse Conditions by Shear Wave Elastography: A Preliminary Study

OBJECTIVES

The primary purpose of this study was to determine whether elasticity quantification of the levator ani muscle (LAM) using shear wave elastography (SWE) is different between women with and without pelvic organ prolapse (POP) and to determine whether LAM elasticity is associated with the prolapse stage or the dimensions of the levator hiatus. The secondary aim was to evaluate the intraobserver and interobserver reliability of LAM elasticity measurements using SWE.

METHODS

The study participants included 20 women with normal pelvic support and 38 women with prolapse (stages I-III). The levator hiatus was imaged by transperineal 3-dimensional ultrasound, and LAM elasticity and the elastic modulus were measured by SWE at rest and while performing the Valsalva maneuver.

RESULTS

The elastic modulus increased significantly from rest to during to maximal Valsalva maneuver (29.2 versus 54.1 kPa; P < .05) in all women. Levator ani muscle elasticity was significantly higher under prolapse conditions than under normal conditions at rest (27.9 versus 31 kPa; P < .001) but was lower during the maximal Valsalva maneuver than under normal conditions (57.3 versus 53.1 kPa; P < .05). Levator ani muscle elasticity at rest was associated with the hiatus area during the Valsalva maneuver (Spearman r = 0.608; P < .001) and distensibility of the levator hiatus (r = 0.594; P < .001), and the hiatus area decreased as the LAM elastic modulus increased during the maximal Valsalva maneuver (r = -0.414; P < .05). Moreover, LAM elasticity was associated with the severity of prolapse (P < .001).

CONCLUSIONS

As a noninvasive quantitative method, SWE, may be used to assess the biomechanical properties of the pelvic floor muscle, providing some research basis for a thorough understanding of POP and its treatment and prevention.

Ultrasound Shear Wave Velocity Varies Across Anatomical Region in Ex Vivo Bovine Ovaries

The physical properties of the ovarian extracellular matrix (ECM) regulate the function of ovarian cells, specifically the ability of the ovary to maintain a quiescent primordial follicle pool while allowing a subset of follicles to grow and mature in the estrous cycle. Design of a long-term, cycling artificial ovary has been hindered by the limited information regarding the mechanical properties of the ovary. In particular, differences in the mechanical properties of the two ovarian compartments, the cortex and medulla, have never been quantified. Shear wave (SW) ultrasound elastography is an imaging modality that enables assessment of material properties, such as the mechanical properties, based on the velocity of SWs, and visualization of internal anatomy, when coupled with B-mode ultrasound. We used SW ultrasound elastography to assess whole, ex vivo bovine ovaries. We demonstrated, for the first time, a difference in mechanical properties, as inferred from SW velocity, between the cortex and medulla, as measured along the length (cortex: 2.57 ± 0.53 m/s, medulla: 2.87 ± 0.77 m/s, p < 0.0001) and width (cortex: 2.99 ± 0.81 m/s, medulla: 3.24 ± 0.97 m/s, p < 0.05) and that the spatial distribution and magnitude of SW velocity vary between these two anatomical planes. This work contributes to a larger body of literature assessing the mechanical properties of the ovary and related cells and specialized ECMs and will enable the rational design of biomimetic tissue engineered models and durable bioprostheses. Impact Statement Shear wave (SW) ultrasound elastography can be used to simultaneously assess the material properties and tissue structures when accompanied with B-mode ultrasound. We report a quantitative difference in mechanical properties, as inferred from SW velocity, between the cortex and medulla, with SW velocity being 11.4% and 8.4% higher in the medulla than the cortex when measured along the length and width, respectively. This investigation into the spatial and temporal variation in SW velocity in bovine ovaries will encourage and improve design of more biomimetic scaffolds for ovarian tissue engineering.

In vivo assessment of the elastic properties of women's pelvic floor during pregnancy using shear wave elastography: design and protocol of the ELASTOPELV study

Background

Animal studies have reported an increase in pelvic floor muscle stiffness during pregnancy, which might be a protective process against perineal trauma at delivery. Our main objective is to describe the changes in the elastic properties of the pelvic floor muscles (levator ani, external anal sphincter) during human pregnancy using shear wave elastography (SWE) technology. Secondary objectives are as follows: i) to look for specific changes of the pelvic floor muscles compared to peripheral muscles; ii) to determine whether an association between the elastic properties of the levator ani and perineal clinical and B-mode ultrasound measures exists; and iii) to provide explorative data about an association between pelvic floor muscle characteristics and the risk of perineal tears.

Methods

Our prospective monocentric study will involve three visits (14–18, 24–28, and 34–38 weeks of pregnancy) and include nulliparous women older than 18 years, with a normal pregnancy and a body mass index (BMI) lower than 35 kg.m^− 2. Each visit will consist of a clinical pelvic floor assessment (using the Pelvic Organ Prolapse Quantification system), an ultrasound perineal measure of the anteroposterior hiatal diameter and SWE assessment of the levator ani and the external anal sphincter muscles (at rest, during the Valsalva maneuver and during pelvic floor contraction), and SWE assessment of both the biceps brachii and the gastrocnemius medialis (at rest, extension and contraction). We will collect data about the mode of delivery and the occurrence of perineal tears. We will investigate changes in continuous variables collected using the Friedman test. We will look for an association between the elastic properties of the levator ani muscle and clinical / ultrasound measures using a Spearman test at each trimester. We will investigate the association between the elastic properties of the pelvic floor muscles and perineal tear occurrence using a multivariate analysis with logistic regression.

Discussion

This study will provide original in vivo human data about the biomechanical changes of pregnant women’s pelvic floor. The results may lead to an individualized risk assessment of perineal trauma at childbirth.

Trial registration

This study was registered on https://clinicaltrials.gov on July 26, 2018 (NCT03602196).

Value of high-frequency two-dimensional ultrasound on evaluating puborectalis muscle

PURPOSE

To explore the value of high-frequency two-dimensional (2D) ultrasound on demonstrating the morphology of puborectalis muscle and detect muscle avulsion.

METHODS

High-frequency 2D ultrasound and tomographic ultrasound image (TUI) were peformed to demonstrate puborectalis muscle and detect muscle avulsion respectively among 158 women with or without significant pelvic organ prolapse (POP) (POP quantification grade 2 or higher). Mean values were compared using student's t test between women with or without avulsion defects. We performed Cohen's Kappa analysis to examine the test agreement between high-frequency 2D ultrasound and TUI mode. Pearson correlation analysis was performed to explore the relationship between the thickness of puborectalis muscle and the measurements of levator-urethra gap (LUG).

RESULTS

The result of high-frequency 2D ultrasound in detecting muscle avulsion agreed well with TUI mode (Kappa 0.88, P < 0.05). Women with muscle avulsion had thinner muscles and larger LUG measurements than those with normal muscle insertion (P < 0.05). Pearson correlation analysis revealed the negative relationship between the thickness of puborectalis muscle and LUG measurements (r = - 0.73).

CONCLUSION

The study confirmed that it was feasible to observe the morphology of puborectalis muscle and detect muscle avulsion by high-frequency 2D ultrasound.

Levator ani evaluation at transperineal elastography in women with deep infiltrating endometriosis postoperatively

OBJECTIVE

To explore whether operation can change the elasticity of levator ani in deep infiltrating endometriosis (DIE) with operation and pharmacotherapy using transperineal elastography.

METHODS

Total thirty-four patients who were diagnosed as DIE were included in the study. Transperineal elastography were performed in all cases preoperatively and postoperatively. The levator ani was evaluated by means of the scoring system and strain ratio (SR) values on maximal Valsalva and quiescent condition, respectively.

RESULTS

On quiescent condition, the preoperative mean elastography scores and SR of the levator ani were statistically significantly higher than the postoperative ones in both shaving technique group and segmental colorectal resection group. And on maximal Valsalva, the preoperative mean elastography scores and SR of the levator ani were statistically significantly lower than the postoperative ones in both groups. After surgery and 6 cycles of GnRHa therapy, the mean elastography score and SR of the levator ani were statistically significantly lower than before GnRHa therapy in shaving technique group on quiescent condition. And on maximal Valsalva, the mean elastography score and SR were statistically higher than before GnRHa therapy. However, in segmental colorectal resection group, the differences were not observed before and following 6 cycles of GnRHa therapy.

CONCLUSION

The elasticity of levator ani of DIE was changed by both shaving technique and segmental colorectal resection. And transperineal elastography could access the alterations.

Tissue biomechanical behavior should be considered in the risk assessment of perineal trauma at childbirth

Perineal trauma at childbirth is associated with strong negative impacts on a woman's health but remains unpredictable. Pregnancy induces several changes in biomechanical behavior in humans as in animals, namely, an increase in ligamentous laxity and an increase in vaginal distensibility. Pelvic floor muscles in rats are reported to exhibit specific behaviors during pregnancy. Increases in both stiffness and the number of sarcomeres in series are observed and might process that protect against perineal trauma at childbirth. Some data in humans have shown that the risk of perineal trauma is highly linked to the intrinsic characteristics of the tissue, suggesting the potential benefit of incorporating intrinsic biomechanical characteristics in the risk prediction for perineal trauma. Shear wave elastography might be a useful noninvasive tool to investigate the elastic properties of these tissues in pregnant women in vivo, with the goal of implementing these properties as a predictive strategy.