Three-dimensional ultrasound of the pelvic floor 2 days after first delivery: influence of constitutional and obstetric factors

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.

An assessment of the relationship between urethral hypermobility as measured by ultrasound and the symptoms of stress urinary incontinence in primiparous women 9-18 months postpartum

Aim

The aim of the study was to estimate the relationship between bladder neck hypermobility as assessed by ultrasound and the occurrence of stress urinary incontinence as measured with the UDI-6 questionnaire in primiparous women 9-18 months postpartum.

Materials and methods

The study included 100 women 9-18 months after their first delivery, 19% of whom (study group) presented with urethral hypermobility. Ultrasound was used to determine the position and mobility of the bladder neck in order to assess the urethral hypermobility. A vector of ≥15 mm was defined as urethral hypermobility. Symptoms of stress urinary incontinence were assessed using question 3 of the UDI-6 questionnaire, in which the presence of symptoms was defined as a response rated from 1 to 4.

Results

We demonstrated a statistically significant relationship between urethral hypermobility and the symptoms of stress urinary incontinence with a statistical significance level of p <0.002.

Conclusions

Stress urinary incontinence is a common disorder in women, the pathophysiology of which is not fully understood. It has adverse effects on the quality of life, perception of one's own body and sexual function. Impairment of urethral fixation may play an important role in the pathophysiology of this common form of urinary incontinence. The study showed that urethral hypermobility, as assessed by ultrasound, contributes to stress urinary incontinence, as measured with the UDI-6 score. Although stress urinary incontinence is a multifactorial disorder influenced by anatomical changes and congenital anatomical features, it is easily diagnosed. Suburethral slings are an effective surgical technique; however, the incidence of postoperative voiding dysfunction or recurrent stress urinary incontinence is 10-20%. Therefore, an assessment of anatomical changes in stress urinary incontinence may help individualize the surgical strategy.

Ultrasound examination of the pelvic floor during active labor: A longitudinal cohort study

INTRODUCTION

There is limited evidence about changes in the pelvic floor during active labor. We aimed to investigate changes in hiatal dimensions during the active first stage of labor and associations with fetal descent and head position.

MATERIAL AND METHODS

We conducted a longitudinal, prospective cohort study at the National University Hospital of Iceland, from 2016 to 2018. Nulliparous women with spontaneous onset of labor, a single fetus in cephalic presentation, and gestational age ≥37 weeks were eligible. Fetal position was assessed with transabdominal ultrasound and fetal descent was measured with transperineal ultrasound. Three-dimensional volumes were acquired from transperineal scanning at the start of the active phase of labor and in late first stage or early second stage. The largest transverse hiatal diameter was measured in the plane of minimal hiatal dimensions. The levator urethral gap was measured as the distance between the center of the urethra and the levator insertion using tomographic ultrasound imaging. Measurements of the levator urethral gap were made in the plane of minimal hiatal dimensions and 2.5 and 5 mm cranial to this.

RESULTS

The final study population comprised 78 women. The mean transverse hiatal diameter increased 12.4% between the two examinations, from 39.4 ± 4.1 mm (±standard deviation) at the first examination to 44.3 ± 5.8 mm at the last examination (p < 0.01). We found a moderate correlation between the transverse hiatal diameter and fetal station at the last examination (r = 0.44, r2  = 0.19; p < 0.01; regression equation y = 2.71 + 0.014x), and a weak correlation between the change in transverse hiatal diameter and change in fetal station (r = 0.29; r2  = 0.08; p = 0.01; regression equation y = 0.24 + 0.012x). Levator urethral gap increased significantly in all three planes on both the left and right sides. Head position was not associated with hiatal measurements after adjusting for fetal station.

CONCLUSIONS

We found a significant, but only modest, increase of the hiatal dimensions during the first stage of labor. The risk of levator ani trauma will therefore be low during this stage. The change in transverse hiatal diameter was associated with fetal descent but not with head position.

Appearance of the levator ani muscle subdivisions on 3D transperineal ultrasound

BACKGROUND

The levator ani muscle (LAM) consists of different subdivisions, which play a specific role in the pelvic floor mechanics. The aim of this study is to identify and describe the appearance of these subdivisions on 3-Dimensional (3D) transperineal ultrasound (TPUS). To do so, a study designed in three phases was performed in which twenty 3D TPUS scans of vaginally nulliparous women were assessed. The first phase was aimed at getting acquainted with the anatomy of the LAM subdivisions and its appearance on TPUS: relevant literature was consulted, and the TPUS scan of one patient was analyzed to identify the puborectal, iliococcygeal, puboperineal, pubovaginal, and puboanal muscle. In the second phase, the five LAM subdivisions and the pubic bone and external sphincter, used as reference structures, were manually segmented in volume data obtained from five nulliparous women at rest. In the third phase, intra- and inter-observer reproducibility were assessed on twenty TPUS scans by measuring the Dice Similarity Index (DSI).

RESULTS

The mean inter-observer and median intra-observer DSI values (with interquartile range) were: puborectal 0.83 (0.13)/0.83 (0.10), puboanal 0.70 (0.16)/0.79 (0.09), iliococcygeal 0.73 (0.14)/0.79 (0.10), puboperineal 0.63 (0.25)/0.75 (0.22), pubovaginal muscle 0.62 (0.22)/0.71 (0.16), and the external sphincter 0.81 (0.12)/0.89 (0.03).

CONCLUSION

Our results show that the LAM subdivisions of nulliparous women can be reproducibly identified on 3D TPUS data.

Levator ani muscle avulsion: a risk factor for persistent postpartum voiding dysfunction

INTRODUCTION AND HYPOTHESIS

Persistent postpartum voiding dysfunction (P-PPVD) is defined as the inability to empty the bladder properly 72 h after delivery despite the use of intermittent urinary catheterization. Our aim was to find predictive factors for P-PPVD and to compare its urogynecologic outcomes with transient dysfunctions.

MATERIALS AND METHODS

A case-control study was performed in a university hospital center between January 2018 and April 2019. The case group included women diagnosed with P-PPVD after vaginal delivery, and the control group included women with PPVD that resolved before 72 h. Patients were followed up at 12 weeks and 12 months postpartum, including an ultrasound assessment of the levator ani muscle (LAM).

RESULTS

Of 2308 deliveries, 1894 (81%) were vaginal, 75 (3.85%) presented PPVD, and 1 lasted > 72 h (0.69% P-PPVD). LAM avulsion (OR 6.3, 95% CI 1.24-32.01) was the only independent risk factor for P-PPVD found. No significant differences in urogynecologic symptoms between transient and persistent PPVD were found in the short and the long term, except that women with P-PPVD had a lower prevalence of urinary incontinence at 12 weeks postpartum.

CONCLUSIONS

PPVD is a common, self-limited event, but in 17.3% of cases persists > 3 days. Levator ani muscle avulsion acts as an independent risk factor for P-PPVD. Early diagnosis and appropriate treatment of P-PPVD can help minimize any clinical implications for long-term urogynecologic disorders.

Association between the side of levator Ani muscle trauma and fetal position at birth - a prospective observational study

INTRODUCTION

Trauma of the levator ani muscle (LAM) is common after vaginal birth and can most reliably be diagnosed by 3-dimensional (3D) translabial ultrasound (TLUS). Multiple risk factors are known in general, but not in association to a specific side of the body. Therefore, our aim was to evaluate different impact factors which cause LAM trauma on either side of the body or bilateral by focusing on the fetal position at birth.

MATERIAL AND METHODS

As part of a prospective cohort study between 3/2017 and 4/2019, we analyzed vaginal births of nulliparous women with singletons in vertex presentation≥36+0 gestational weeks. We evaluated their pelvic floor for hematomas, partial and complete LAM avulsions by 3D TLUS 2-4 days postpartum and searched for an association between the affected body side and different fetal, maternal and obstetrical factors.

RESULTS

71 out of 213 women (33.3%) suffered from LAM trauma - 17 (23.9%) on the right side, 20 (28.2%) on the left side and 34 (47.9%) bilateral. No association between the different evaluated factors and the affected body side could be identified, except for the quality of fetal heart rate tracing.

CONCLUSIONS

No significant impact factors of LAM trauma could be associated with a specific side of the body. Other possible mechanisms need investigation in the future, such as the time of the birth canal and the fetus to adapt to each other, including adequate time for the tissue to stretch and the fetus to rotate into the ideal position within the LAM hiatus.

EINLEITUNG

Levatormuskelverletzungen sind häufig nach Vaginalgeburten und können zuverlässig mittels translabialem 3D-Ultraschall diagnostiziert werden. Diverse Risikofaktoren sind hierfür bekannt, allerdings keine hinsichtlich der Assoziation zu einer der beiden Körperseiten. Daher war das Ziel dieser Arbeit, verschiedene Einflussfaktoren im Rahmen vaginaler Geburten zu evaluieren, welche eine Levatorverletzung auf einer der beiden Körperseiten bzw. beidseitig begünstigen, v. a. hinsichtlich der Kindsposition im Geburtskanal.

MATERIAL UND METHODIK

In einer prospektiven Kohortenstudie analysierten wir von 3/2017-4/2019 Erstgebärende mit vaginalen Einlingsgeburten aus Schädellage≥36+0 SSW. Wir evaluierten 2-4 Tage postpartal ihren Beckenboden mittels 3D-Ultraschall hinsichtlich Hämatomen sowie partiellen und kompletten Levatoravulsionen und suchten nach Assoziationen zwischen der betroffenen Körperseite und fetalen, maternalen und geburtshilflichen Einflussfaktoren.

ERGEBNISSE

Von 213 Frauen erlitten 71 (33.3%) eine Levatorverletzung - 17 (23.9%) rechtsseitig, 20 (28.2%) linksseitig und 34 (47.9%) beidseitig. Es wurden keine Assoziationen zwischen den untersuchten Einflussfaktoren und der betroffenen Körperseite gefunden, bis auf die Qualität der fetalen Herzfrequenz.

DISKUSSION

Es konnten keine signifikanten Einflussfaktoren für das Auftreten einer Levatorverletzung einer spezifischen Körperseite eruiert werden. Daher bedarf es in Zukunft der Untersuchung weiterer Mechanismen, wie der Adaptationsvorgänge von Geburtskanal und Fet und der adäquaten Zeit für das Gewebe zur notwendigen Dehnung, v. a. im Bereich der Levatoröffnung.

Influence of the disengagement of the forceps on levator ani muscle injuries in instrumental delivery: A multicenter study

INTRODUCTION

Forceps use is the main risk factor for levator ani muscle (LAM) injuries. We believe that the disengagement of the forceps branches before delivery of the fetal head could influence LAM injuries, so we aimed to determine the influence of the disengagement of the forceps on the occurrence of LAM avulsion during forceps delivery.

MATERIAL AND METHODS

A prospective, observational, multicenter study was conducted with 261 women who underwent forceps delivery. The women were classified according to whether the branches of the forceps had been disengaged before delivery of the fetal head. LAM avulsion was defined using a multislice mode (3 central slices).

RESULTS

In all, 255 women completed the study (160 without disengagement and 95 with disengagement). LAM avulsions were observed in 37.9% of women in the group with disengagement and in 41.9% of women in the group without disengagement. The crude OR (without disengagement vs with disengagement) for avulsion was 0.90 (95% CI 0.49-1.67, P = 0.757) and an adjusted OR of 0.82 (95% CI 0.40-1.69, P = 0.603).

CONCLUSIONS

We did not observe a statistically significant reduction in the LAM avulsion rate with disengagement of the forceps branches before delivery of the fetal head.

[Childbirth pelvic floor trauma: Anatomy, physiology, pathophysiology and special situations - CNGOF perineal prevention and protection in obstetrics guidelines]

OBJECTIVES

To assess whether pelvic size and shape, spinal curvature, perineal body length and genital hiatus size are associated with the incidence of childbirth pelvic floor trauma. Special situations, such as obesity, ethnicity and hyperlaxity, will also be studied.

METHODS

A bibliographic research using Pubmed and Cochrane Library databases was conducted until May 2018. Publications in English and French were selected by initial reading of the abstracts. Randomized trials, meta-analyzes, case-control studies and large cohorts were studied in a privileged way.

RESULTS

A pubic arch angle<90° (measured clinically) does not appear to increase the risk of OASIS (Level 3), but appears to be a risk factor for postnatal anal incontinence at short-term, but not at long-term (Level 3). Measurement of pelvic dimensions and the subpubic angle is not recommended to predict OASIS or to choose the mode of delivery for the purpose of protecting the perineum (GradeC). Prenatal measurement of both perineal body (Level 3) and genital hiatus (Level 2) does not predict the incidence of 2nd or 3rd degree OASIS. Therefore, the routine prenatal measurement of the length of the perineal body or the genital hiatus is not recommended for any objective related to perineal protection (Grade C). Levator avulsion, resulting in a widening of the genital hiatus, is potentially a source of long-term pelvic floor dysfunction. Biomechanical models suggest that performing a mediolateral episiotomy and applying the fingers to the posterior perineum at the time of expulsive phase may reduce pelvic floor trauma. Obese women have a longer perineal body (Level 3), and obesity does not seem to increase the risk of OASIS (Level 2). There is no difference between Asian and non-Asian women perineal body (Level 3). No studies have validated that the liberal practice of episiotomy in Asian women reduced the risk of OASIS. It is therefore not recommended to practice an episiotomy for simple ethnic reasons in Asian women (GradeC). Compared to white women, black women do not appear to have an increased risk of OASIS and even appear to have a decreased risk of perineal tears of all stages (Level 2). Ligament hyperlaxity seems to be associated with an increased risk of OASIS (Level 2).

CONCLUSIONS

Prenatal assessment of pelvis bone, spine curvature, perineal body and genital hiatus do not allow to predict the incidence of childbirth pelvic floor trauma. Obesity and ethnicity are not risk factors for OASIS.

New Measures for Predicting Birth-Related Pelvic Floor Trauma

OBJECTIVES

The aim of this study was to establish the predictive role of obstetric variables for obstetric outcomes and birth related levator ani muscle (LAM) trauma.

METHODS

In this prospective study, women underwent 3-dimensional pelvic floor ultrasound at their first appointment at 36 weeks and also 3 months postpartum. The measurements included minimal levator hiatus circumference (MLHC) and the ratio of fetal head circumference to MLHC = head-induced stretch ratio (HISR) as an indicator of the discrepancy between passage and passing canal. To derive the true impact of baby's mass on the levator ani musculature, we devised the levator ani stretch ratio (LASR), which was calculated by multiplying the HISR and the baby's weight.

RESULTS

Data set of 173 women was available for analysis. Mean HISR and LASR values were statistically different across all binary outcome categories, with 1 exception for HISR and levator ani injury. The odds ratios for LASR indicated positive and statistically significant associations with all obstetric outcomes examined. The probability of the LASR correctly classifying those with the adverse obstetric outcome, as estimated by the area under the curve, ranged from 0.64 to 0.80 with the strongest discriminatory ability observed for severe LAM trauma.

CONCLUSIONS

Fetal head circumference/mother MLHC ratio (HISR) is associated with longer length of second stage of labor, assisted delivery, and increased severity of perineal trauma. Similar associations were observed for LASR, but in addition, LASR had good discriminatory ability to identify severe LAM trauma.

Evaluation of levator ani muscle throughout the different stages of labor by transperineal 3D ultrasound

OBJECTIVE

Description and assessment by 3-D transperineal ultrasound of modifications suffered by pelvic floor muscles during the passage of the fetal head through the birth canal during the second stage of labor, as well as the identification of the precise moment in which levator ani muscle avulsion takes place.

MATERIALS AND METHODS

Patients included were 35 primigravidae, recruited during the first stage of labor, with at term pregnancy (37-42 weeks), without serious maternal-fetal pathology and cephalic presentation. A prospective observational study of 35 primigravidae, recruited during the first stage of labor, with at term pregnancy (37-42 weeks), with fetus in cephalic presentation and without serious maternal-fetal pathology. Sonographic evaluation was carried out by 3-D transperineal ultrasound during the first and second stages of labor (with fetal head in 1st, 2nd-3rd and 4th planes of Hodge), immediately postpartum and 6 months postpartum. Ultrasound parameters studied were antero-posterior and transverse diameters, as well as levator hiatus area and levator ani muscle thickness and area.

RESULTS

Twenty-one patients were studied (15 spontaneous deliveries; 6 instrumental deliveries). When measured with fetal head in the 4th plane of Hodge, a significant increase both in the levator hiatus area (15.39 cm² /15.68 cm² /20.96 cm² /42.55 cm² /22.92 cm² /18.18 cm² ; P < 0.0005) and in the levator ani muscle area (8.78 cm² /9.18 cm² /9.69 cm² /15.07 cm² /11.33 cm² /12.36 cm² ; P < 0.0005) was identified. Four cases of unilateral right avulsion (two vacuum and two forceps deliveries) were identified.

CONCLUSIONS

We conclude that the phase of delivery that causes a major increase in the area of the levator hiatus area and in the levator ani muscle area is when the fetal head reaches the 4th plane of Hodge. Furthermore, data in our paper indicates that the exact moment in which the avulsion of the levator ani muscle is produced is when the bulging of the fetal head on the maternal perineum occurs.

The Epidemiology of Pelvic Floor Disorders and Childbirth: An Update

Using a lifespan model, this article presents new scientific findings regarding risk factors for pelvic floor disorders (PFDs), focusing on the role of childbirth in the development of single or multiple coexisting PFDs. Phase I of the model includes predisposing factors, such as genetic predisposition and race. Phase II includes inciting factors, such as obstetric events. Prolapse, urinary incontinence (UI), and fecal incontinence (FI) are more common among vaginally parous women, although the impact of vaginal delivery on risk of FI is less dramatic than prolapse and UI. Phase III includes intervening factors, such as age and obesity.

Reliability of new three-dimensional ultrasound technique for pelvic hiatal area measurement

OBJECTIVE

To assess the reproducibility of a new technique for three-/four-dimensional (3D/4D) ultrasound imaging of the pelvic floor: OmniView™ volume contrast imaging (VCI) for measurement of the pelvic hiatal area on maximum contraction and Valsalva maneuver. In addition, we aimed to study the intermethod agreement between the new technique and the 3D/4D render method.

METHODS

We acquired one static 3D and two dynamic 4D transperineal volumes (one obtained during contraction and one during Valsalva maneuver) from 35 nulliparous asymptomatic healthy volunteers and 35 women with symptoms of pelvic floor dysfunction. Each 3D dataset was analyzed using the OmniView-VCI technique to measure the pelvic hiatal area at rest, on maximum contraction and on maximum Valsalva. Analysis was performed twice by the same operator and once by another operator in order to assess intra- and interobserver reproducibility. All measurements were repeated by one operator using the 3D/4D render method to evaluate the intermethod agreement. Reproducibility and intermethod agreement were studied by means of intraclass correlation coefficients (ICC) and the Bland-Altman method.

RESULTS

Measurement of hiatal area using the OmniView-VCI technique showed excellent intraobserver and interobserver reproducibility in both asymptomatic and symptomatic women at rest, on contraction and on Valsalva maneuver. In addition, excellent agreement was demonstrated between OmniView-VCI and 3D/4D render in both groups (ICCs on Valsalva in asymptomatic and symptomatic women were 0.894 and 0.975, respectively). No systematic difference was noted in any of the reliability studies performed.

CONCLUSIONS

OmniView-VCI is a reliable method for pelvic hiatal area measurement. Both rendering mode and OmniView-VCI can be used interchangeably for assessing pelvic hiatal area. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

[Applicability of 3/4D transperineal ultrasound for the diagnosis of anal sphincter injury during the immediate pospartum]

BACKGROUND

The most common cause of anal sphincter injuries in women is vaginal birth. Endo-anal ultrasound is currently used for the diagnosis of anal sphincter defect. However, due to the inconvenience caused, it is not an applicable technique during the immediate post-partum. The aim of this study was to determine whether transperineal ultrasound in 3/4D is a useful diagnostic method for the assessment of anal sphincter during the immediate post-partum.

MATERIAL AND METHODS

A prospective study was conducted on the vaginal deliveries performed between September 2012 and June 2013 in the Valme University Hospital (Seville). Obstetric and foetal parameters that could influence the onset of perineal tears were studied. The patients underwent a transperineal 3/4D ultrasound and a multislice study (48hours after birth).

RESULTS

The study included 146 puerperal women. The sphincter complex was assessed in all of them during the immediate post-partum. External anal injuries were observed in 10.3% of the cases. In 8.2% of cases, the primary suture of the external anal sphincter was detected during ultrasound examination, and 2.1% of asymptomatic lesions were diagnosed only with post-partum ultrasound. None of the patients reported discomfort or pain.

CONCLUSIONS

The 3-dimensional transperineal ultrasound is helpful in determining the primary repair of the anal sphincter during the immediate post-partum, with no discomfort for patients, as well as for establishing those early sphincter injuries that go unnoticed during vaginal delivery.

Translabial three-dimensional ultrasound investigation of the levator hiatus in postpartum women

PURPOSE

This study utilized translabial three-dimensional ultrasound to investigate the morphological characteristics of the levator hiatus and provide sonographic evidence for assessing pelvic floor dysfunction in postpartum women.

METHODS

Two-hundred and one singleton primiparae without any complications underwent translabial three-dimensional ultrasound at 6 and 18 weeks after delivery, with 12 participants lost to follow-up at 18 weeks. Fifty nulliparae were enrolled as the control group. Levator hiatal morphology at rest and on Valsalva maneuver was assessed by experienced sonographers, specifically evaluating the anteroposterior diameter, left-to-right diameter, and area.

RESULTS

In postpartum women at 6 weeks after delivery, all the levator hiatal parameters were significantly higher compared with those of the control group. At 18 weeks, the hiatal parameters were better than at 6 weeks but still higher than in the nulliparous controls. In all three groups, the hiatal parameters were significantly higher during the Valsalva maneuver than at rest.

CONCLUSIONS

Postpartum women are prone to develop pelvic floor dysfunction as shown by an enlarged levator hiatus. Translabial three-dimensional ultrasound can be used to effectively assess the morphology and structural alterations of the levator hiatus in postpartum women, providing reliable pelvic floor imaging for early screening, diagnosis, and prevention of pelvic floor dysfunction.

A new simple technique for 3-dimensional sonographic assessment of the pelvic floor muscles

OBJECTIVES

The purpose of this study was to assess the reproducibility of a new technique for 3-dimensional (3D) pelvic floor sonography: OmniView combined with Volume Contrast Imaging (VCI; GE Healthcare, Kretz Ultrasound, Zipf, Austria) for pelvic hiatal area measurement. In addition, we aimed to study the intermethod agreement between the new technique and the standard 3D rendering method.

METHODS

We acquired a static 3D sonographic transperineal volume from 124 nulliparous asymptomatic women and 118 women with symptoms of pelvic floor dysfunction. Each 3D data set was analyzed by the OmniView-VCI technique to measure the pelvic hiatal area twice by one operator and once by another to assess intraobserver and interobserver reproducibility. The first operator later measured the hiatal area using the 3D rendering method to evaluate intermethod agreement. Reproducibility and intermethod agreement were studied by the intraclass correlation coefficient and Bland-Altman method.

RESULTS

Hiatal area measurements by the OmniView-VCI technique showed high intraobserver and interobserver reproducibility in both asymptomatic and symptomatic women. In addition, high agreement was shown between the new technique and 3D rendering in both groups. No systematic differences were noted in any of the reliability studies performed. The new technique took slightly less time to calculate the hiatal area than the standard rendering method in both asymptomatic and symptomatic women.

CONCLUSIONS

OmniView-VCI is a reliable method for pelvic hiatal area measurement. Further studies are needed to assess its reliability under contraction and the Valsalva maneuver and to evaluate its usefulness and reproducibility for diagnosis of levator ani lesions.

Levator hematoma at the attachment zone as an early marker for levator ani muscle avulsion

OBJECTIVES

Childbirth causes overstretching of the levator ani muscle (LAM), predisposing to avulsion. LAM avulsion has not been evaluated early postpartum using endovaginal ultrasound (EVUS). The aim of this study was to evaluate the relationship between hematomas and LAM avulsion using EVUS and palpation early and late postpartum.

METHODS

Nulliparous women were studied prospectively at 36 weeks' gestation and within 4 days and 3 months postpartum. Palpation and high-frequency three-dimensional EVUS were performed. Two independent investigators reviewed the scans.

RESULTS

No antenatal LAM avulsions were found (n = 269). 114/199 (57.3%) women seen early postpartum agreed to examination. 27/114 (23.7%) had well delineated, hypoechoic areas consistent with hematomas (100% agreement), 26 following vaginal delivery, one following emergency Cesarean section. In total, 38 hematomas were found (11 bilateral, 16 unilateral). Hematomas away from the attachment zone of the LAM to the pubic bone (n = 22) resolved. Hematomas at the attachment zone (n = 16) manifested as pubococcygeus avulsions 3 months postpartum. In addition to these 16 avulsions, we found another 20 at 3 months postpartum. 13/20 were not scanned early postpartum and in seven no hematomas were seen, but avulsion was seen early postpartum. Overall, LAM avulsion was found in 23/191 (12.0%) women (13 bilateral, 10 unilateral) 3 months postpartum. Hematomas were significantly associated with episiotomy, instrumental delivery and increased hiatal measurements. Palpation was unreliable early postpartum as only seven avulsions were diagnosed.

CONCLUSION

Hematomas at the site of LAM attachment to the pubic bone always result in avulsion diagnosed 3 months postpartum. However, one third of avulsions are not preceded by a hematoma at the site of LAM attachment to the pubic bone.

Three-dimensional ultrasound of pelvic floor: is there a correlation with delivery mode and persisting pelvic floor disorders 18-24 months after first delivery?

OBJECTIVE

Three-dimensional (3D) transperineal ultrasound has been shown to be a reliable and reproducible method for visualization of morphological changes in the female levator ani muscle. The aim of this study was to evaluate the relationship between persisting pelvic floor disorders 18-24 months after first delivery, biometric measurements of the pelvic floor and mode of delivery.

METHODS

In this prospective observational study, we recruited on their second day after delivery 130 primiparous women. All were Caucasian and their pregnancies had been singleton with cephalic presentation. 3D transperineal ultrasound was performed, with standardized settings, on the second day (results published previously) and 18-24 months after delivery. Volumes were obtained at rest and on Valsalva maneuver and biometric measurements of the levator hiatus were determined in the axial plane. Obstetric and constitutional parameters were obtained from our clinical files and, 18-24 months after the delivery, a standardized questionnaire was used to evaluate persisting pelvic floor disorders. Ultrasound measurements at 18-24 months were compared according to clinical symptoms of pelvic floor disorders and mode of delivery, including a subgroup analysis of vaginal (spontaneous vs operative vaginal) and Cesarean (primary i.e. elective vs secondary i.e. after onset of labor) delivery groups.

RESULTS

Seventy-seven (59%) women had complete follow-up at 18-24 months. Biometric measurements showed a significantly larger hiatal area in the vaginal delivery group than in the Cesarean section group 2 years after delivery (P < 0.01), whereas subgroup analysis within the vaginal and Cesarean delivery groups did not show significant differences. Although there was no statistical correlation between delivery mode and persisting stress urinary incontinence, women with persisting stress urinary incontinence 2 years after delivery had a larger hiatal area than did women without this clinical symptom (P < 0.01). There were no significant differences in hiatal dimensions in women with bladder urgency or dyspareunia.

CONCLUSIONS

3D transperineal ultrasound, which is easily accessible, can provide useful information on morphological changes of the female pelvic floor. Women with a spontaneous or operative vaginal first delivery had a significantly larger hiatal area and axial distension than did women whose first delivery was by Cesarean section, even 2 years after delivery. Performing 3D ultrasound after the first delivery may help to identify women at high risk for persisting pelvic floor disorders.

Levator ani subtended volume: a novel parameter to evaluate levator ani muscle laxity in pelvic organ prolapse

OBJECTIVE

We describe a new parameter based on magnetic resonance 3-dimensional (3D) reconstructions proposed to evaluate levator ani muscle (LAM) laxity in women with pelvic organ prolapse (POP).

STUDY DESIGN

This is an institutional review board-approved, retrospective chart review of 35 women with POP, stages I-IV. The 3D Slicer software package was used to perform 2-dimensional and 3D measurements and the levator ani subtended volume (LASV) was described. Basically, the LASV represents the volume contained by LAM between 2 planes, which coincides with pubococcygeal line and H line. Correlations among measurements, ordinal POP stages, POP Quantification (POPQ) individual measurements, and validated questionnaires were performed.

RESULTS

The LASV differentiated major (III and IV) from minor (I and II) POPQ stages, which positively correlated to POP stages and POPQ individual measurements.

CONCLUSION

The LASV is a promising parameter to evaluate the LAM laxity.

Four-dimensional sonographic evaluation of avulsion of the levator ani according to delivery mode

OBJECTIVE

To determine the frequency of avulsion of the levator ani muscle in primiparous women according to delivery mode, using introital four-dimensional ultrasonography.

METHODS

We performed a prospective observational study at a tertiary obstetric unit. One hundred and eighty primiparous women were included and divided into three groups: normal vaginal delivery without episiotomy, forceps delivery and Cesarean section groups. Between 40 and 120 days after delivery, four-dimensional ultrasonography was performed in order to evaluate the integrity of the levator ani muscle. The operator was blinded to all clinical data and was not aware of delivery mode. The influence of other variables associated with delivery such as birth weight, body mass index, maternal age and use of epidural anesthesia was also studied.

RESULTS

Avulsion of the puborectalis component of the levator ani muscle was detected on ultrasonography in 61.7% of women who had undergone a forceps delivery, compared with 13.3% of those who had had a normal vaginal delivery and 0% of those who had had a Cesarean section. Bilateral avulsion was observed in 12/60 (20.0%) of the forceps group and in 2/60 (3.3%) of the normal vaginal delivery group (P < 0.001). Other variables did not seem to influence prevalence.

CONCLUSIONS

Forceps delivery is associated with an increased rate of avulsion of the puborectalis component of the levator ani muscle. The effect of forceps use is independent of other delivery-related variables.