Ultrasound assessment of pelvic floor muscle contraction: reliability and development of an ultrasound-based contraction scale

Feasibility and reproducibility of new technique for measurement of transverse diameter of levator ani muscle hiatus using two-dimensional transperineal ultrasound in nulliparous women with term pregnancy

OBJECTIVES

The aim of the present study was two-fold. Firstly, we aimed to develop and describe a technique for measurement of the transverse diameter (TD) of the levator ani muscle (LAM) hiatus in the coronal view using two-dimensional (2D) transperineal ultrasound (TPUS) in nulliparous women with a term pregnancy. Secondly, we aimed to evaluate the feasibility and reproducibility of 2D-TPUS assessment of LAM hiatal TD and assess intermethod agreement between 2D-TPUS and three-dimensional (3D) TPUS measurement of TD in the axial plane, which is considered the gold standard in nulliparous women with term pregnancy.

METHODS

We recruited a group of nulliparous women with term pregnancy before the onset of labor. The study was conducted in two phases: Phase 1 involved developing and describing the 2D-TPUS technique for measuring LAM hiatal TD, and Phase 2 focused on assessing the technique's feasibility, reproducibility and intermethod agreement with 3D-TPUS measurement of LAM hiatal TD. In Phase 1, we enrolled 30 women. Each woman underwent acquisition of a 3D-TPUS volume, which was analyzed using multiplanar mode to identify and determine the appearance of the lateral borders of the LAM in the coronal plane, at the level of the plane of minimal hiatal dimensions. These borders were used as landmarks for TD measurement. Additionally, we measured the distance between the plane used for TD measurement and the center of the urethra in the axial view. In Phase 2, we recruited 100 women. Each woman underwent acquisition of three 2D-TPUS videoclips in the coronal plane, each encompassing a sweep of the entire LAM hiatus, and a 3D volume, all obtained during rest. On the 2D videoclips, TD was measured twice by one operator and once by another operator. In the 3D volume, TD was measured once, by one operator, in the axial plane; this measurement was considered the gold standard. Each operator was blinded to all other measurements during their assessments. We analyzed intraobserver and interobserver reproducibility and performed an intermethod (2D vs 3D) comparison. Bland-Altman analysis was conducted, and Levene's W0 test and Student's t-test were performed to explore clinical factors that might contribute to systematic differences.

RESULTS

In Phase 1, we identified successfully the landmarks denoting the lateral borders of the LAM hiatal TD in the coronal view. These appeared as two symmetrical hypoechogenic indentations located at the inner border of the hyperechogenic structure of the LAM, at the point of maximum distance between the two sides of the LAM. The distance between the urethra and the plane where TD should be measured using 3D-TPUS in the axial plane had a median of 4 mm and varied from 0 to 9 mm. This enabled us to describe a method for assessing LAM hiatal TD in the coronal plane using 2D-TPUS. In Phase 2, LAM hiatal TD was measured successfully in all 2D and 3D acquisitions from the entire group of 100 women. The analyses for intraobserver and interobserver reproducibility and the intermethod comparison (2D vs 3D) revealed almost perfect agreement in TD measurements using 2D-TPUS, with intraclass correlation coefficients of 0.95 (95% CI, 0.92-0.96), 0.87 (95% CI, 0.78-0.92) and 0.85 (95% CI, 0.78-0.90), respectively. The average differences between measurements were 0.1 mm for intraobserver, 1.0 mm for interobserver and 0.2 mm for intermethod repeatability. No systematic differences were observed in any of the measurement sets, except in the interobserver analysis, although this difference was clinically not significant (38.2 vs 37.2 mm, P = 0.01). None of the examined clinical factors (maternal body mass index and maternal age) exhibited a statistically significant impact on intraobserver, interobserver or intermethod reliability.

CONCLUSIONS

Utilizing our technique, described herein, to measure the LAM hiatal TD in the coronal view using 2D-TPUS is not only feasible but also highly reproducible and accurate in nulliparous women with term pregnancy. Moreover, it yields measurements that are comparable to those obtained in the reconstructed axial plane generated by 3D-TPUS. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Soft-tissue dystocia due to paradoxical contraction of the levator ani as a cause of prolonged second stage: concept, diagnosis, and potential treatment

Smaller pelvic floor dimensions seem to have been an evolutionary need to provide adequate support for the pelvic organs and the fetal head. Pelvic floor dimension and shape contributed to the complexity of human birth. Maternal pushing associated with pelvic floor muscle relaxation is key to vaginal birth. Using transperineal ultrasound, pelvic floor dimensions can be objectively measured in both static and dynamic conditions, such as pelvic floor muscle contraction and pushing. Several studies have evaluated the role of the pelvic floor in labor outcomes. Smaller levator hiatal dimensions seem to be associated with a longer duration of the second stage of labor and a higher risk of cesarean and operative deliveries. Furthermore, smaller levator hiatal dimensions are associated with a higher fetal head station at term of pregnancy, as assessed by transperineal ultrasound. With maternal pushing, most women can relax their pelvic floor, thus increasing their pelvic floor dimensions. Some women contract rather than relax their pelvic floor muscles under pushing, which is associated with a reduction in the anteroposterior diameter of the levator hiatus. This phenomenon is called levator ani muscle coactivation. Coactivation in nulliparous women at term of pregnancy before the onset of labor is associated with a higher fetal head station at term of pregnancy and a longer duration of the second stage of labor. In addition, levator ani muscle coactivation in nulliparous women undergoing induction of labor is associated with a longer duration of the active second stage of labor. Whether we can improve maternal pelvic floor relaxation with consequent improvement in labor outcomes remains a matter of debate. Maternal education, physiotherapy, and visual feedback are promising interventions. In particular, ultrasound visual feedback before the onset of labor can help women increase their levator hiatal dimensions and correct levator ani muscle coactivation in some cases. Ultrasound visual feedback in the second stage of labor was found to help women push more efficiently, thus obtaining a lower fetal head station at ultrasound and a shorter duration of the second stage of labor. The available evidence on the role of any intervention aimed to aid women to better relax their pelvic floor remains limited, and more studies are needed before considering its routine clinical application.

Is there a synergistic relationship between diaphragm and pelvic floor muscles in pregnant women?

OBJECTIVE

The aim of this study is to examine whether there is a synergistic relationship between the diaphragm and pelvic floor muscles (PFM) in pregnant women.

MATERIAL AND METHODS

Our study was carried out as a cross-sectional study in primigravid pregnants in the second and third trimesters. Superficial electromyography (EMG), 2D/3D ultrasonography (USG), pulmonary function test (PFT), PERFECT, maximum expiratory pressure (MEP) and inspiratory pressure (MIP) measurements were used to evaluate pelvic floor and diaphragm muscle functions during pregnancy. Mann-Whitney U test was used to show the change in the second and third trimesters, and Spearman correlation was used to determine the relationship.

RESULTS

No correlation was found between the EMG data of the PFM and diaphragm, or between the USG data of the PFM and diaphragm in all participants, in the second and third trimesters. In the third trimester of the study, diaphragmatic thickness and levator hiatal area (LHA) decreased and both diaphragm and PFM % MVC EMG parameters increased. In the third trimester, FVC, MIP, MEP decreased, and nonsignificant increase in FEV1, FEV1/FVC and peak ekspiratuar flow(PEF) were detected. A significant correlation was found between pelvic floor levator hiatal area USG and FEV1/FVC in both trimesters (r: 0,577p: 0,004).

CONCLUSION

There may be a synergistic relationship between the diaphragm and PFM in pregnant women, the relationship may weaken as pregnancy progresses, and there may be no coactivation relationship between the two muscles. In order to prevent the occurrence of pelvic floor dysfunction during pregnancy and to increase the effect of rehabilitation programs, the relationship between the diaphragm and the PFM should be determined and more studies should be conducted.

Comparative study of female pelvic floor among undeformed high-resolution thin-sectional anatomical (visible human) images and MRI and ultrasound images

PURPOSE

Using visible human, MRI and ultrasound images, we aim to provide an anatomical basis for the identification and diagnosis of pelvic floor structure and disease by ultrasound imaging.

METHODS

One Chinese visible human (CVH) image, one American visible human image, 9 MRI images of normal volunteers, and 40 ultrasound images of normal volunteers or pelvic organ prolapse patients were used. Pelvic organs, pelvic floor muscles, and the connective tissue in CVH, VHP, MRI, and ultrasound images were selected for comparative study.

RESULTS

We successfully identified the boundary of the anal sphincter complex, including the subcutaneous, superficial, and deep parts of the external anal sphincter, conjoined longitudinal muscles and internal anal sphincter; the levator ani muscle (LAM), including the internal and external parts of the pubovisceral muscle and the superficial and deep parts of the puborectal muscle; the urethral sphincter complex, including the urethral sphincter proper and the urethral compressor; and the perineal body, the rectoperineal muscle and superficial transverse perineal muscle.

CONCLUSIONS

We successfully recognized and studied the location, subdivisions, 2D morphology and spatial relationships of the LAM, anal sphincter complex, urethral sphincter complex and perineal body in ultrasound images, thereby helping sonologists or clinicians accurately identify pelvic floor muscles and supporting structures in ultrasound images.

Pelvic floor status in opera singers. a pilot study using transperineal ultrasound

BACKGROUND

Control of pelvic floor muscles (PFM) is emphasized as important to obtain functional breath support in opera singing, but there is not much research that proves PFM function as part of breath support in classical singing. Transperineal ultrasound is a reliable method for quantification of PFM contraction in urogynecology. Our aim was to establish if transperineal ultrasound can be used for observation of movement of the PFM during singing and to quantify pelvic floor contraction.

METHODS

Cross sectional study of 10 professional opera singers examined with transperineal ultrasound in the supine position at rest and contraction, and standing at rest and during singing. Levator hiatal area was measured in a 3D rendered volume. Levator hiatal anteroposterior (AP) diameter and bladder neck distance from symphysis were measured in 2D images.

RESULTS

The AP diameter was shortened from supine rest to contraction (15 mm), standing (6 mm) and singing (9 mm), all p < 0.01. The bladder neck had a non-significant descent of 3 mm during singing. The mean proportional change in AP diameter from rest to contraction was 24.2% (moderate to strong contraction) and from rest to singing was 15% (weak to moderate contraction).

CONCLUSIONS

Transperineal ultrasound can be used to examine the PFM during singing. The classically trained singers had good voluntary PFM contraction and moderate contraction during singing. AP diameter was significantly shortened from supine to upright position, with further shortening during singing, confirming that female opera singers contracted their pelvic floor during singing.

Effects of Pelvic Floor Muscle Physiotherapy on Urinary, Bowel, and Sexual Functions in Women with Deep Infiltrating Endometriosis: A Randomized Controlled Trial

Background and Objectives: Endometriosis is a chronic and recurrent disease defined as the presence and proliferation of endometrial glands and stroma outside the uterine cavity. It affects up to 6-10% of women of reproductive age and can be classified into superficial, ovarian, and deep infiltrating endometriosis (DIE). Deep infiltrating endometriosis can be associated with pain symptoms and pelvic floor muscle hypertone. Moreover, it may be responsible of bowel, urinary, and sexual dysfunctions with impairment of women's quality of life. Few studies have investigated the role of physiotherapy in women with DIE. Here, we aimed first to evaluate the effects of pelvic floor physiotherapy (PFP) on urinary, bowel, and sexual functions. Secondly, we aimed to evaluate the effects of ultrasound visual feedback during PFP on pelvic floor and subjective modifications in the frequency of sexual intercourse. Materials and Methods: This randomized controlled trial was conducted between June 2018 and December 2019 at our tertiary center. Nulliparous women with DIE and superficial dyspareunia were enrolled. At first examination, levator hiatal area (LHA) assessed with 3D/4D transperineal ultrasound, pain symptoms, urinary, bowel, and sexual functions were evaluated. Then, women were randomly assigned to no intervention (control group) or treatment with five individual sessions of PFP (experimental group), and after four months women underwent a second examination. Urinary, bowel, and sexual functions were assessed with validated questionnaires at first and second examinations. In particular, the Bristol Female Lower Urinary Tract Symptoms questionnaire was used to evaluate urinary symptoms, the Knowles-Eccersley-Scott-Symptom questionnaire to assess the presence of constipation, and the Female Sexual Function Index to investigate sexual function. Study outcomes were the comparisons among groups in terms of differences in actual changes in median of questionnaire scores between first and second examinations. Results: Thirty women (17 in the experimental group and 13 in the control group) completed the study. No significant differences were found between the two groups regarding urinary, bowel, and sexual functions, although women in the experimental group showed a tendency towards an improvement in constipation symptoms. Conclusion: In women with DIE, PFP does not appear to affect urinary, bowel, and sexual functions. Therefore, despite the improvement in superficial dyspareunia, chronic pelvic pain, and PFM relaxation with high treatment satisfaction, women should be informed about the unclear impact of PFP on urinary, bowel, and sexual functions. Larger studies are necessary to further investigate the impact of PFP on these functions.

Developing new ways to assess neural control of pelvic organ function in spinal conditions: ICI-RS 2023

OBJECTIVES

Several central nervous system (CNS) centers affect muscle groups of the lower urinary tract (LUT) and anorectal tract (ART) via autonomic and somatic pathways, working in different modes (storage or expulsion). Hence spinal cord dysfunction can affect the LUT and ART by several possible mechanisms.

METHODS

This review reports the discussions of a workshop at the 2023 meeting of the International Consultation on Incontinence Research Society, which reviewed uncertainties and research priorities of spinal dysfunction.

RESULTS

Discussion focussed on the levator ani nerve, mechanisms underpinning sensory function and sensation, functional imaging, dyssynergia, and experimental models. The following key research questions were identified. (1) Clinically, how can we evaluate the levator ani muscle to support assessment and identify prognosis for effective treatment selection? (2) How can we reliably measure levator ani tone? (3) How can we evaluate sensory information and sensation for the LUT and the ART? (4) What is the role of functional CNS imaging in development of scientific insights and clinical evaluation? (5) What is the relationship of detrusor sphincter dyssynergia to renal failure?

CONCLUSIONS

Spinal cord dysfunction can fundamentally disrupt LUT and ART function, with considerable clinical impact. The evaluation needs to reflect the full scope of potential problems, and new clinical and diagnostic approaches are needed, for prognosis and treatment. The preclinical science evaluating spinal cord function in both LUT and ART storage and elimination remains a major priority, even though it is a challenging experimental context. Without this underpinning evidence, development of new clinical evidence may be held back.

Impact of parity and delivery mode on pelvic floor function in young women: a 3D ultrasound evaluation

INTRODUCTION AND HYPOTHESIS

The objectives were to evaluate clinical and anatomical parameters assessed by three-dimensional pelvic floor ultrasound (3D ultrasound) in parous and nulliparous women of childbearing age and to assess underreported symptoms of sexual dysfunction (SD), urinary incontinence (UI) and flatus incontinence (FI).

METHODS

Women without complaints of pelvic floor dysfunction, aged 20-50 years, were eligible for this prospective cross-sectional study. They completed the King's Health Questionnaire, Female Sexual Function Index and St Mark's Incontinence Score adapted for this study. Next, a physical examination and 3D ultrasound were performed. The scores obtained in the questionnaires were compared with the 3D ultrasound data.

RESULTS

In total, 326 women were invited to participate. Of these, 203 women met the inclusion criteria, and their cases were classified as nulliparity (NU, 59), vaginal delivery (VD, 80), forceps delivery (FD, 18) and caesarean section (CS, 48). These groups were homogeneous regarding age (p=0.096), parity (p=0.051) and body mass index (p=0.06). The hiatal dimension (HD; p=0.003) and transverse diameter (TD) (p=0.001) were significantly different among the groups. Compared with the NU and CS groups, the VD and FD groups had an increased HD and TD. The frequencies of underreported symptoms identified by questionnaires were as follows: SD (46.3%), UI (35%) and FI (28%). After VD and FD, women were more likely to present UI (p<0.001), FI (p<0.001) and SD (p=0.002) than the women with NU and those who had undergone a CS. UI was related to a greater HD (p=0.002) and anteroposterior diameter (p=0.022), FI was associated with a thinner left pubovisceral muscle (p=0.013), and SD was related to a greater HD (p=0.026).

CONCLUSIONS

Three-dimensional ultrasound can identify mild morphological changes in young women with apparently normal physical examinations, mainly after VD and FD. In such individuals, these findings are associated with higher incidences of underreported sexual, urinary and anal symptoms.

Three-Dimensional Ultrasound Evaluation of Pelvic Floor Muscle Contraction in Women Affected by Deep Infiltrating Endometriosis: Application of a Quick Contraction Scale

OBJECTIVES

Using transperineal 3D/4D ultrasound, we evaluated the prevalence of the various categories of a 4-point pelvic contraction scale among women affected by ovarian endometriosis (OE), deep infiltrating endometriosis (DIE), and healthy controls.

METHODS

This prospective study was conducted on nulliparous women scheduled for surgery to remove endometriosis, and nulliparous healthy volunteers who did not show any clinical or sonographic signs of endometriosis, who served as controls. Patients were subjected to 3D/4D transperineal ultrasound obtaining measurements of the antero-posterior diameter (APD), both at rest and during maximal pelvic floor muscle (PFM) contraction (PFMC). The difference of APD from rest to maximal PFMC was then calculated as percent change from baseline (ΔAPD) and patients were thus categorized using the 4-point pelvic contraction scale.

RESULTS

One hundred sixty-four patients were considered for the study. Mean difference in APD between relaxed state and maximal PFMC was 23.3 ± 7.9% (range 2.4-40.0) in controls, 20.5 ± 9.0% (range 0.0-37.3) in patients with OE, and 14.6 ± 10.4% (range 0.0-37.1) in patients with DIE (F-test = 19.5, P-value < .001). A significant negative correlation was found between the contraction scale and dyspareunia (rs = -0.17, P = .032), and it appeared to be stronger among patients with DIE (rs = -0.20, P = .076).

CONCLUSIONS

PFM function in endometriotic patients could be assessed reliably through this 4-point scale. The rapid identification of women suffering from PFM dysfunction, along with deep dyspareunia, could enable gynecologists to offer them additional therapies, such as PFM rehabilitation.

Are levator hiatal dimensions in mid-pregnancy associated with mode of delivery?

INTRODUCTION AND HYPOTHESIS

Slow progress of labour is a risk for operative delivery. Smaller levator hiatal dimensions are possible risk factors for slow progress and operative delivery. Our aim was to explore associations between hiatal dimensions antenatally, duration of second stage of labour and mode of delivery.

METHODS

Prospective cohort study of 65 nullipara examined at 20 weeks gestation and 6 months postpartum. Levator hiatal anteroposterior diameter and area were measured using 2D/3D transperineal ultrasound and compared between women with normal vaginal delivery and operative delivery (vacuum or caesarean) using t-test and with Spearman's rank to explore correlations with duration of second stage. ROC analysis established a cut-off for high risk of operative delivery.

RESULTS

Two-dimensional anteroposterior diameter and 3D hiatal area at rest were smaller in women with operative delivery than with normal delivery, 5.0 cm vs. 5.7 cm, p = 0.007 and 18.5 cm² vs. 14.9 cm², p < 0.001. From the ROC curve for 2D anteroposterior diameter, a cut-off of 5.6 cm, (sensitivity = 0.94, specificity = 0.63) and for 3D hiatal area a cut-off of 17.6 cm² (sensitivity = 0.94, specificity = 0.65) predicted operative delivery. We found inverse correlations between second stage of labour and anteroposterior diameter at rest, r = -0.330, contraction, r = -0.365, area at rest, r = -0.324, and contraction, r = -0.521, all p < 0.05.

CONCLUSIONS

Smaller hiatal dimensions at 20 weeks gestation were associated with longer second stage of labour and increased risk of operative delivery in nullipara. A 2D anteroposterior hiatal diameter < 5.6 cm and 3D hiatal area < 17.6 cm² at rest imply increased risk of operative delivery.

Effects of Adding Ultrasound Biofeedback to Individualized Pelvic Floor Muscle Training on Extensibility of the Pelvic Floor Muscle and Anterior Pelvic Organ Prolapse in Postmenopausal Women

The aim of the study was to determine effects of adding transperineal ultrasound (TPUS) biofeedback to individualized pelvic floor muscle training (PFMT) on extensibility of the pelvic floor muscle and anterior pelvic organ prolapse (POP) in postmenopausal women. A total of 77 patients with POP at stage I or stage II were admitted to Beijing Shijitan Hospital, China, from January 2017 to October 2018. They were randomly divided into a control group (CG) (n = 37) or a study group (SG) (n = 40). Both SG and CG received a 12-week PFMT including health education, verbal instruction, and home training. However, the SG, but not the CG, received additional TPUS biofeedback. Data of these patients were retrospectively reviewed. The distance from the lowest point of the bladder to the inferior-posterior margin of the symphysis pubis (BSP) and the levator hiatus area (LHA) were measured on maximal Valsalva via TPUS before and after the 12-week PFMT. Correct pelvic floor muscle contraction (PFMC) rates before and after PFMT were compared between the two groups. The correct PFMC rate was higher in the SG than that in the CG (92.5% vs. 73%; x² = 5.223, p=0.022). The BSP was increased but the LHA was reduced after the 12-week PFMT in both groups compared to those before PFMT (all p < 0.05). However, after the PFMT, the SG showed greater improvement than the CG for both BSP (0.77 ± 0.71 cm vs. 0.11 ± 0.66 cm, p < 0.05) and LHA (20.69 ± 2.77 cm² vs. 22.85 ± 3.98 cm², p < 0.05). TPUS might be an effective biofeedback tool for PFMT in clinical practice. Individualized PFMT with TPUS biofeedback could significantly attenuate POP severity and strengthen the extensibility of pelvic floor muscle in postmenopausal women when they are under increased intraabdominal pressure.

Development and validation of a composite AI model for the diagnosis of levator ani muscle avulsion

OBJECTIVE

To assess the feasibility and reliability of a composite AI model for the diagnosis of levator ani muscle (LAM) avulsion of tomographic ultrasound imaging (TUI).

METHODS

Ultrasonic images of the pelvic floor from a total of 304 patients taken from January 2018 to October 2020 were included. All patients included underwent standardized interviews and transperineal ultrasound (TPUS). Transfer-learning and ensemble-learning methods were adopted to develop the proposed model on the basis of three classic convolutional neural networks (CNN). Confusion matrix (CM) and the ROC statistic were used to assess the effectiveness of the proposed model. Gradient-weighted class activation mappings (Grad-CAMs) were used to help enhance the interpretability of the proposed model.

RESULTS

Of the 304 patients included, 208 were in the derivation cohort (108 LAM avulsion and 100 normal) and 96 (39 LAM avulsion and 57 normal) were in the validation cohort. The proposed model in LAM avulsion diagnosis outperformed other models and a junior clinician in both the test set of derivation cohort and the validation cohort, with accuracies of 0.95 and 0.81, and AUCs of 0.98 and 0.86, respectively. According to the heatmap of Grad-CAMs, the proposed model mainly localizes areas between the pubic symphysis and the bilateral insertion point of LAM when making a diagnosis, which is exactly the region of interest in clinical practice.

CONCLUSION

The proposed model using ultrasonic images of the pelvic floor may be a promising tool in assisting the diagnosis of LAM avulsion in clinical practice.

KEY POINTS

• First AI-assisted model for levator ani muscle avulsion diagnosis • Diagnosis accuracy of less-experienced clinicians could be improved using the proposed model.

The impact of levator ani muscle trauma and contraction on recurrence after prolapse surgery

Introduction and hypothesis

The objective was to explore the impact of levator ani muscle (LAM) trauma and pelvic floor contraction on symptoms and anatomy after pelvic organ prolapse (POP) surgery.

Methods

Prospective study including 200 women with symptomatic POP ≥ grade 2 examined 3 months prior to and 6 months after surgery. Prolapse in each compartment was graded using the Pelvic Organ Prolapse Quantification (POP-Q) system, and women answered yes/no to a question about bulge sensation. Pelvic floor muscle contraction was assessed with transperineal ultrasound measuring proportional change in levator hiatal anteroposterior diameter from rest to contraction. LAM trauma was diagnosed using tomographic ultrasound imaging. Statistical analysis was performed using multivariate logistic regression analysis.

Results

A total of 183 women (92%) completed the study. Anatomical recurrence (POP ≥ grade 2) was found in 76 women (42%), and a bulge sensation was reported by 35 (19%). Ninety-two women (50%) had LAM trauma, and this was associated with increased risk of anatomical recurrence (OR 2.1 (95% CI 1.1–4.1), p = 0.022), but not bulge sensation (OR 1.1 (95% CI 0.5–2.4), p = 0.809). We found a reduced risk of bulge sensation for women with absent to weak contraction compared with normal to strong contraction (OR 0.4 (95% CI 0.1–0.9), p = 0.031), but no difference in risk for POP ≥ 2 after surgery (OR 1.5 (95% CI 0.8–2.9), p = 0.223).

Conclusions

Levator ani muscle trauma was associated with increased risk of anatomical failure 6 months after POP surgery. Absent to weak pelvic floor muscle contraction was associated with reduced risk of bulge sensation after surgery.

The correlation between levator ani co-activation and fetal head regression on maternal pushing at term

OBJECTIVE

To assess the correlation between fetal head regression and levator ani muscle (LAM) co-activation under Valsalva maneuver.

STUDY DESIGN

This study was a secondary analysis of a prospective cohort study on the association between the angle of progression (AoP) and labor outcome. We scanned a group of nulliparous women at term before the onset of labor at rest and under maximum Valsalva maneuver. In addition to the previously calculated AoP, in the present study, we measured the anteroposterior diameter of LAM hiatus (APD) on each ultrasound image. LAM co-activation was defined as APD at Valsalva less than that at rest, whereas fetal head regression was defined as AoP at Valsalva less than that at rest. We calculated the correlation between the two phenomena. Finally, we examined various labor outcomes according to the presence, absence, or co-existence of these two phenomena.

RESULTS

We included 469 women. A total of 129 (27.5%) women presented LAM co-activation while 50 (10.7%) showed head regression. Only 15 (3.2%) women showed simultaneous head regression and LAM co-activation. Women with coexisting LAM co-activation and head regression had the narrowest AoP at Valsalva in comparison with other study groups (p < .001). In addition, they had the highest risk of Cesarean delivery (40%) and longest first, second, and active second stage durations, although none of these reached statistical significance.

CONCLUSION

In nulliparous women at term before the onset of labor fetal head regression and LAM co-activation at Valsalva are two distinct phenomena that uncommonly coexist.

The maternal pelvic floor and labor outcome

Vaginal birth is the major cause of pelvic floor damage. The development of transperineal ultrasound has improved our understanding of the relationship between vaginal birth and pelvic floor dysfunction. The female pelvic floor dimensions and function can be assessed reliably in pregnant women. Maternal pushing associated with pelvic floor muscle relaxation is the central requirement of vaginal birth. Many studies have evaluated the role of the pelvic floor on labor outcomes. Smaller levator hiatal dimensions and incomplete or absent levator ani muscle relaxation seem to be associated with a longer duration of the second stage of labor and a higher risk of cesarean and operative deliveries. Here, we presented an overview of the current knowledge of the correlation between female pelvic floor dimension and function, as assessed by transperineal ultrasound, and labor outcome.

The correlation between transperineal ultrasound assessment of the levator ani muscle and postpartum urinary incontinence

AIMS

The primary aim of the present study was to assess the association between levator ani muscle (LAM) integrity and function on the one hand, and the risk of urinary incontinence (UI) on the other. A secondary objective was to assess the association between fundal pressure in the second stage of labor (Kristeller maneuver) and the risk of postpartum UI.

METHODS

In this prospective cohort study, women underwent a clinical and transperineal ultrasound examination at rest, at pelvic floor muscle contraction (PFMC), and at Valsalva maneuver 3-6 months after their first vaginal delivery. LAM avulsion and levator hiatal area (LHA) were evaluated. In addition, women were interviewed about the presence of UI, whether stress (SUI) or urgency (UUI).

RESULTS

Overall, data of 244 women were analyzed. SUI was reported in 50 (20.5%), while UUI was reported in 19 (7.8%) women. Women who reported SUI had a higher prevalence of LAM avulsion and less proportional reduction in LHA from rest to a maximum contraction in comparison to women with no SUI. Women who reported UUI had a greater LHA at rest, during contraction, and during maximal Valsalva in comparison to women without UUI. No significant association was found between the Kristeller maneuver and the incidence of any UI.

CONCLUSION

Levator ani avulsion and less proportional reduction of LHA with PFMC appear to be associated with a higher risk of postpartum urinary stress incontinence.

Is pelvic floor muscle contractility an important factor in anal incontinence?

OBJECTIVE

Pelvic floor muscle contractility (PFMC) may contribute to anal continence. The aim of this study was to assess the association between clinical and sonographic measures of PFMC and anal incontinence (AI) symptoms, after controlling for anal sphincter and levator ani muscle (LAM) trauma.

METHODS

This was a retrospective study of 1383 women assessed at a tertiary center between 2013 and 2016. All patients underwent an interview, including the St Mark's incontinence score (SMIS) in those who reported AI symptoms, a clinical examination, including assessment of PFMC using the modified Oxford scale (MOS), and four-dimensional translabial ultrasound (TLUS). Sonographic measures of PFMC, i.e. cranioventral shift of the bladder neck (BN) and reduction of anteroposterior (AP) diameter of the levator hiatus, were measured offline using ultrasound volumes obtained at rest and on maximum pelvic floor contraction. The reviewer was blinded to all clinical data.

RESULTS

Of the 1383 patients assessed during the study period, seven were excluded due to missing imaging data, leaving 1376 for analysis. Mean age of the participating women was 55 years and mean body mass index was 29 kg/m² . AI was reported by 221 (16.1%) women, with a mean SMIS of 11.8. Mean MOS grade was 2.3. On TLUS, mean BN cranioventral shift was 5.9 mm and mean AP diameter reduction was 8.1 mm. LAM avulsion and significant external anal sphincter (EAS) defect were diagnosed in 24.8% and 8.7% patients, respectively. On univariate analysis, sonographic measures of PFMC were not associated with AI. Lower MOS grade was associated with symptoms of AI; however, statistical significance was lost on multivariate analysis.

CONCLUSION

Clinical and sonographic measures of PFMC were not significantly associated with AI symptoms after controlling for EAS and LAM trauma. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Assessment of levator hiatal area using 3D/4D transperineal ultrasound in women with deep infiltrating endometriosis and superficial dyspareunia treated with pelvic floor muscle physiotherapy: randomized controlled trial

OBJECTIVES

Deep infiltrating endometriosis (DIE) is associated with chronic pelvic pain, dyspareunia and pelvic floor muscle hypertonia. The primary aim of this study was to evaluate the effect of pelvic floor physiotherapy (PFP) on the area of levator ani hiatus during Valsalva maneuver, assessed using transperineal ultrasound, in women with DIE suffering from superficial dyspareunia.

METHODS

This was a randomized controlled trial of 34 nulliparous women diagnosed with DIE and associated superficial dyspareunia. After an initial clinical examination, all patients underwent three-dimensional/four-dimensional (3D/4D) transperineal ultrasound to measure the levator hiatal area (LHA) at rest, on maximum pelvic floor muscle contraction and on maximum Valsalva maneuver, and were asked to rate their pain symptoms using a numerical rating scale (NRS). Eligible women were assigned randomly (1:1 ratio) to no intervention (control group, 17 women) or treatment with five individual sessions of PFP (study group, 17 women). Four months after the first examination, all women underwent a second evaluation of pain symptoms and LHA on transperineal ultrasound. The primary outcome measure was the percentage change in LHA on maximum Valsalva maneuver between the baseline and follow-up examinations. The percentage changes in pain symptoms between the two examinations, including superficial and deep dyspareunia, dysmenorrhea, chronic pelvic pain, dysuria and dyschezia, were also evaluated.

RESULTS

Thirty women, comprising 17 in the study group and 13 in the control group, completed the study and were included in the analysis. The percentage change in LHA on maximum Valsalva maneuver between the two examinations was higher in the study group than in the control group (20.0 ± 24.8% vs -0.5 ± 3.3%; P = 0.02), indicating better pelvic floor muscle relaxation. After PFP treatment, the NRS score for superficial dyspareunia remained almost unchanged in the control group (median change in NRS (Δ-NRS), 0 (interquartile range (IQR), 0-0)) while a marked reduction was observed in the study group (median Δ-NRS, -3 (IQR, -4 to -2); P < 0.01). Moreover, there was a significant difference between the PFP and control groups with regards to the change in chronic pelvic pain (median Δ-NRS, 0 (IQR, -2 to 0) vs 0 (IQR, 0-1); P = 0.01).

CONCLUSIONS

In women with DIE, PFP seems to result in increased LHA on Valsalva maneuver, as observed by 3D/4D transperineal ultrasound, leading to improved superficial dyspareunia, chronic pelvic pain and pelvic floor muscle relaxation. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Establishing a peripartum perineal trauma clinic: a narrative review

INTRODUCTION AND HYPOTHESIS

Obstetric anal sphincter injury (OASI) is not rare, and its consequences are multiple and potentially severe, especially for young women. Some dedicated perineal clinics have been established to improve the management of OASI. Despite their obvious importance, these specific clinics are underrepresented and underdeveloped. The objectives of this review are to explore various options for developing a peripartum perineal clinic and to compare the different practices regarding the mode of delivery for subsequent pregnancies after an OASI.

METHODS

This narrative review covers information from patients' questionnaires specific to anal incontinence, anal physiology assessment, pelvic floor and anal sphincter imaging, and the arguments for choosing the mode of delivery after an OASI.

RESULTS

This review highlights the extensive range of practices regarding the delivery mode after an OASI throughout national professional organizations and experienced perineal clinics.

CONCLUSION

This review summarizes the different choices in developing a perineal clinic to facilitate their development in promoting health care and education specific for peripartum women concerning the perineal consequences of delivery for obstetrician-gynaecologists, family doctors, and residents.

Transperineal ultrasound assessment of maternal pelvic floor at term and fetal head engagement

OBJECTIVES

To evaluate the association between pelvic floor dimensions in nulliparous women at term and fetal head engagement, as assessed by transperineal ultrasound.

METHODS

This was a prospective observational study of nulliparous women at term. Before the onset of labor, transperineal ultrasound was used to measure the anteroposterior diameter (APD) of the levator hiatus and the angle of progression (AoP) at rest, on maximum pelvic floor muscle contraction and on maximum Valsalva maneuver (before and after visual feedback). We assessed the correlation between pelvic floor static and dynamic dimensions (levator hiatal APD and levator ani muscle coactivation) and AoP, which is an objective index of fetal head engagement.

RESULTS

In total, 282 women were included in the analysis. Among these, 211 (74.8%) women had a vaginal delivery while 71 (25.2%) had a Cesarean delivery. AoP was narrower in the Cesarean-delivery group at rest, on maximum pelvic floor muscle contraction and on maximum Valsalva, whereas no differences in levator hiatal APD were found between the two groups. We found a negative correlation between levator hiatal APD at rest, on maximum pelvic floor muscle contraction and on maximum Valsalva and the duration of the second stage of labor. There was a positive correlation between AoP and levator hiatal APD on maximum Valsalva maneuver after visual feedback (r = 0.15, P = 0.01). Women with levator ani muscle contraction on Valsalva maneuver (i.e. coactivation), both pre and post visual feedback, had a narrower AoP at rest and on maximum Valsalva. After visual feedback, women with levator ani muscle coactivation had a longer second stage of labor than did those without (80.8 ± 61.4 min vs 62.9 ± 43.4 min (P = 0.04)).

CONCLUSIONS

Smaller pelvic floor dimensions and levator ani muscle coactivation are associated with higher fetal head station and with a longer second stage of labor in nulliparous women at term. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

The dynamic change of the anteroposterior diameter of the levator hiatus under Valsalva maneuver at term and labor outcome

AIM

The aim of the present study was to evaluate the correlation between the proportional change of anteroposterior diameter (APD) of levator hiatus from rest to maximum Valsalva maneuver in nulliparous women at term and labor outcome.

METHODS

We prospectively recruited nulliparous women at term before the onset of labor. Women underwent a two-dimensional transperineal ultrasound, measuring the APD of the levator hiatus at rest and under maximum Valsalva's maneuver. APD change from rest to maximum Valsalva was described both in terms of absolute figures and proportional change. Correlation of APD change with the mode of delivery and with labor durations was assessed.

RESULTS

Overall, 486 women were included in the analysis. No significant association between change in APD and the mode of delivery. We found a significant negative correlation between change of APD from rest to Valsalva and the duration of active second stage both in terms of absolute change (Pearson's r = -0.138, P = .009) and in terms of proportional change (Pearson's r = -0.154, P = .004). Survival outcomes based on Cox-regression model showed that APD was independently associated with the duration of active second stage of labor after adjusting for epidural analgesia, maternal age and body mass index (hazard ratio, 1.008; 95% confidence interval, 1.001-1.016; P = .04) CONCLUSION: Women with higher increase of the anteroposterior diameter of the levator hiatus from rest to Valsalva have a shorter active second stage of labor.

Type of levator ani muscle avulsion as predictor for the disappearance of avulsion

OBJECTIVES

The objective of our study was to establish whether the type of levator ani muscle (LAM) avulsion diagnosed 6 months after delivery influences the integrity of the LAM at 1 year after delivery and determine its influence on the levator hiatus area.

STUDY DESIGN

This observational prospective cohort study included 192 primiparous women with vaginal delivery. Transperineal ultrasound examinations were performed at 6 months and 1 year postpartum. Levator hiatus measurements (anteroposterior diameter, transverse diameter, and area) were performed in the plane of minimal dimensions. Complete avulsion was defined based on maximum contraction in multislice mode. Type I LAM avulsion was present when most lateral fibers of the pubovisceral muscle were observed at its insertion at the pubic level (the arch of the elevator remained intact). Type II LAM avulsion was defined as a complete detachment of the pubovisceral muscle from its insertion at the pubic level.

RESULTS

In total, 192 patients were recruited after delivery; 48 patients were diagnosed with complete LAM avulsion, and 13 patients with avulsion did not attend the second ultrasound follow-up at 1 year after delivery. Thirty-five patients with complete LAM avulsion were included in the study. At 6 months after delivery, 51 LAM avulsions were observed in 35 patients (including bilateral LAM avulsion in 16 cases), of which 54.9% were right avulsions and 45.1% left avulsions. Furthermore, 11 (five right and six left) were type I LAM avulsions at the 6-month assessment, and all of these had disappeared 1 year after delivery. However, none of the type II LAM avulsions (23 right and 17 left) observed at 6 months had disappeared at the second ultrasound examination. There were no differences between the LAM areas detected at the first and second ultrasound examinations (10.2 ± 3.3 vs 9.3 ± 1.8; P = .404).

CONCLUSIONS

The type of LAM avulsion observed at 6 months after childbirth predicts LAM persistence at 1 year postpartum.

Effect of preoperative pelvic floor muscle training on pelvic floor muscle contraction and symptomatic and anatomical pelvic organ prolapse after surgery: randomized controlled trial

OBJECTIVES

To evaluate the effect of preoperative pelvic floor muscle training (PFMT) on pelvic floor muscle (PFM) contraction, symptoms of pelvic organ prolapse (POP) and anatomical POP, 6 months after prolapse surgery, and to assess the overall changes in PFM contraction, POP symptoms and pelvic organ descent after surgery.

METHODS

This was a randomized controlled trial of 159 women with symptomatic POP, Stage 2 or higher, scheduled for surgery. Participants were randomized to intervention including daily PFMT from inclusion to surgery (n = 81) or no intervention (controls; n = 78). Participants were examined at inclusion, on the day of surgery and 6 months after surgery. PFM contraction was assessed by: vaginal palpation using the Modified Oxford scale (MOS; 0-5); transperineal ultrasound, measuring the percentage change in levator hiatal anteroposterior diameter (APD) from rest to maximum PFM contraction; vaginal manometry; and surface electromyography (EMG). POP distance from the hymen in the compartment with the most dominant prolapse and organ descent in the anterior, central and posterior compartments were measured on maximum Valsalva maneuver. POP symptoms were assessed based on the sensation of vaginal bulge, which was graded using a visual analog scale (VAS; 0-100 mm). Linear mixed models were used to assess the effect of PFMT on outcome variables.

RESULTS

Of the 159 women randomized, 151 completed the study, comprising 75 in the intervention and 76 in the control group. Mean waiting time for surgery was 22 ± 9.7 weeks and follow-up was performed on average 28 ± 7.8 weeks after surgery. Postoperatively, no difference was found between the intervention and control groups with respect to PFM contraction assessed by vaginal palpation (MOS, 2.4 vs 2.2; P = 0.101), manometry (19.4 vs 19.7 cmH₂ O; P = 0.793), surface EMG (33.5 vs 33.1 mV; P = 0.815) and ultrasound (change in hiatal APD, 20.9% vs 19.3%; P = 0.211). Furthermore, no difference between groups was found for sensation of vaginal bulge (VAS, 7.4 vs 6.0 mm; P = 0.598), POP distance from the hymen in the dominant prolapse compartment (-1.8 vs -2.0 cm; P = 0.556) and sonographic descent of the bladder (0.5 vs 0.8 cm; P = 0.058), cervix (-1.3 vs -1.1 cm; P = 0.569) and rectal ampulla (0.3 vs 0.4 cm; P = 0.434). In all patients, compared with findings at initial examination, muscle contraction improved after surgery, as assessed by palpation (MOS, 2.1 vs 2.3; P = 0.007) and ultrasound (change in hiatal APD, 17.5% vs 20.1%; P = 0.001), and sensation of vaginal bulge was reduced (VAS, 57.6 vs 6.7 mm; P < 0.001). In addition, compared with the baseline examination, POP distance from the hymen in the dominant prolapse compartment (1.9 vs -1.9 cm; P < 0.001) and sonographic descent of the bladder (1.3 vs 0.6 cm; P < 0.001), cervix (0.0 vs -1.2 cm; P < 0.001) and rectal ampulla (0.9 vs 0.4 cm; P = 0.001) were reduced.

CONCLUSIONS

We found no effect of preoperative PFMT on PFM contraction, POP symptoms or anatomical prolapse after surgery. In all patients, PFM contraction and POP symptoms were improved at the 6-month follow-up, most likely due to the anatomical correction of POP. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.