Three-dimensional ultrasound imaging of the pelvic floor: the effect of parturition on paravaginal support structures

The effect of prolapse surgery on voiding function

INTRODUCTION AND HYPOTHESIS

Of women with symptomatic prolapse, 13-39% experience voiding dysfunction (VD). The aim of our observational cohort study was to determine the effect of prolapse surgery on voiding function.

METHODS

Retrospective analysis of 392 women who underwent surgery between May 2005 and August 2020. All had a standardized interview, POP-Q, uroflowmetry and 3D/4D transperineal ultrasound (TPUS) pre-and postoperatively. Primary outcome was change in VD symptoms. Secondary outcomes were changes in maximum urinary flow rate (MFR) centile and post-void residual urine (PVR). Explanatory measures were change in pelvic organ descent as seen on POP-Q and TPUS.

RESULTS

Of 392 women, 81 were excluded due to missing data, leaving 311. Mean age and BMI were 58 years and 30 kg/m2, respectively. Procedures performed included anterior repair (n = 187, 60.1%), posterior repair (n = 245, 78.8%), vaginal hysterectomy (n = 85, 27.3%), sacrospinous colpopexy (n = 170, 54.7%) and mid-urethral sling (MUS) (n = 192, 61.7%). Mean follow-up was 7 (1-61) months. Pre-operatively, 135 (43.3%) women reported symptoms of VD. Postoperatively, this decreased to 69 (22.2%) (p < 0.001), and of those, 32 (10.3%) reported de novo VD. The difference remained significant after excluding concomitant MUS surgery (n = 119, p < 0.001). Postoperatively, there was a significant decrease in mean PVR (n = 311, p < 0.001). After excluding concomitant MUS surgery, there was a significant increase in mean MFR centile (p = 0.046).

CONCLUSIONS

Prolapse repair significantly reduces symptoms of VD and improves PVR and flowmetry.

Relationship between urethral motion profile and parity assessed by translabial ultrasound imaging

PURPOSE

This study aims to describe the differences in the urethral motion profile (UMP) of primiparous and multiparous women immediately postpartum.

METHODS

This prospective study recruited 65 women (29 primiparous, 36 multiparous) one-seven days postpartum. The patients underwent a standardised interview and two-dimensional translabial ultrasound (TLUS). To evaluate the UMP, the urethra was manually traced and divided into five segments with six equidistant points. The mobility vector (MV) for each point was calculated as [Formula: see text]. A Shapiro-Wilk test was conducted to test normality. An independent t-test and a Mann-Whitney test were conducted to express differences between the groups. The Pearson correlation coefficient was used to determine the relationships among MVs, parity and confounders. Finally, a univariate generalised linear regression analysis was performed.

RESULTS

MV1-MV4 were found to be normally distributed. A significant difference for all MVs, except for MV5, was demonstrated between parity groups (MV1: t = 3.88 (p < .001), MV2: t = 3.82 (p < .001), MV3: t = 2.65 (p = .012), MV4: t = 2.54 (p = .015), MV6: U = 150.00 (exact sig. two tailed = .012)). A strong-to-very strong mutual correlation was observed between MV1 to MV4. The univariate generalised linear regression showed that parity can predict up to 26% of urethral mobility.

CONCLUSION

This study shows that multiparous women have significantly higher urethral mobility compared to primiparous women in the first week postpartum, with the most significant effect observed in the proximal urethra.

A Qualitative and Quantitative Study to Evaluate the Effectiveness and Safety of Magnetic Stimulation in Women with Urinary Incontinence Symptoms and Pelvic Floor Disorders

Background and objectives: Involuntary loss of urine owed to dysfunction of the detrusor muscle or muscles of the pelvic floor is known as urinary incontinence (UI). In this study, ultrasound monitoring was employed for the first time to measure the usefulness and safety of electromagnetic stimulation for women with Stress or Urge UI. Materials and Methods: A total of 62 women were enrolled, with a mean age of 55.1 (±14.5); 60% of them were menopausal and presented with urinary incontinence (UI). Eight validated questionnaires were used to evaluate Stress UI, prolapse, overactive bladder urge, faecal incontinence, and quality of life, and the whole study population was tested with ultrasounds at the beginning and at the end of the treatment cycle. The device used was a non-invasive electromagnetic therapeutic system composed of a main unit and an adjustable chair applicator shaped for deep pelvic floor area stimulation. Results: Ultrasound measurements and validated questionnaires revealed a consistent and statistically significant (p < 0.01) improvement of the mean scores when pre- and post-treatment data were considered. Conclusions: Study results showed that the proposed treatment strategy led to a significant improvement in Pelvic Floor Muscle (PFM) tone and strength in patients with UI and pelvic floor disorders, without discomfort or side effects. The demonstration was qualitatively carried out with validated questionnaires and quantitatively with ultrasounds exams. Thus, the "chair" device we used represents valuable and effective support that could be widely employed in the gynaecological field for patients affected by different pathologies.

Does Cystocele Type Vary Between Vaginally Parous and Nulliparous Women?

OBJECTIVES

To evaluate whether cystocele type varies with vaginal parity.

METHODS

Retrospective analysis of 464 vaginally nulliparous women seen at 2 urogynecology units between November 2006 and November 2019. A control group consisted of 871 vaginally parous women seen between July 2017 and November 2019. Patients underwent a standardized interview, POPQ, urodynamic testing, and translabial ultrasound. On imaging, significant cystocele was defined as bladder descent to ≥10 mm below symphysis pubis. Volume datasets were analyzed offline and blinded against clinical data.

RESULTS

Of 5266 women seen during the inclusion period, 464 were vaginally nulliparous. Three were excluded due to missing data, leaving 461. A control group of 871 parous women was generated from patients seen during the last 2.5 years of the inclusion period. Vaginally nulliparous women were presented at a younger age compared to vaginally parous women (P < .001). Symptoms of prolapse were reported in 104 (22%) nulliparae and 489 (56%) parous women (P < .0001). Vaginally parous women demonstrated more bladder descent (P < .0001) and more cystocele (418/871 versus 43/461, P < .0001), with a higher proportion of type III cystocele (cystocele with intact retrovesical angle) (20/43 versus 273/ 418, P < .0001). Cystourethrocele (Green type II) was more common in nulliparae and cystocele type III in parous women (P = .015). On multivariate analysis, these differences in proportions remained significant (P = .049).

CONCLUSIONS

Nulliparity was associated with a higher proportion of Green type II cystoceles. Green type III cystocele was more common in vaginally parous women, suggesting that the latter may be more likely to be due to childbirth-related pelvic floor trauma.

Effects of yoga on the intervention of levator ani hiatus in postpartum women: a prospective study

[Purpose] This study aimed to explore the application value of yoga intervention in early postpartum recovery of the levator ani muscle hiatus (LAH) area. [Participants and Methods] Females in natural labor from May 2020 to November 2020 in the Third People’s Hospital of Sun Yat-sen University Ultrasound Research Center were prospectively included for a pelvic ultrasound examination. The control group received no intervention. The experimental group received 60-min yoga once a week from week 1 to week 12 postpartum. A pelvic ultrasound examination was performed on the week 6 and week 12 postpartum. The LAH area was measured at rest, during contraction and Valsalva maneuver. [Results] A total of 128 participants who met the inclusion criteria were selected and randomly assigned to the control group (n=66) and the experimental group (n=62) in pre and post intervention design. No significant differences were found in age, parity, body mass index, and fetal weight between the control and experimental groups. Further, no significant difference was observed in the LAH area between the control and experimental groups at rest, during contraction and Valsalva maneuver on the week 6 postpartum. However, the LAH area in experimental group significantly reduced at rest, during contraction and Valsalva maneuver on the week 12 postpartum. The differences of LAH area (date week 6 minus date week 12) in the control group at rest, during contraction and Valsalva maneuver were 0.12 ± 3.12 cm², 0.80 ± 2.29 cm², and 0.80 ± 4.22 cm², while in the control these were 1.95 ± 3.41 cm², 1.39 ± 1.91 cm², and 3.81 ± 5.49 cm², respectively. Compared with control group, the differences of LAH area significantly increased in experimental group at rest and during Valsalva maneuver. [Conclusion] Yoga intervention can help in the recovery of LAH.

The usual suspect: cross-sectional study of fundal pressure at second stage of delivery and the association with pelvic floor damage

INTRODUCTION AND HYPOTHESIS

Uterine fundal pressure is applied to accelerate birth by increasing the expulsive force of the uterus in the second stage of delivery. The aim of the study was to evaluate the effect of using uterine fundal pressure during the second stage of delivery on the rate of pelvic floor damage among primiparous women using three-dimensional transperineal ultrasonography.

METHODS

The women were divided into two groups: the fundal pressure group included women where the fundal pressure maneuver was applied (n = 39); the control group included women who delivered spontaneously without fundal pressure (n = 47). 3D-TPU was performed within 48 h of delivery, and LAM biometry, LAM defect and loss of tenting were determined.

RESULTS

Anteroposterior hiatal dimensions on resting, maximal Valsalva and maximal PFMC were found to be higher in the fundal pressure group (p < 0.0001, p = 0.008, p = 0.007, respectively). The mean hiatal area at rest was larger in the fundal pressure group than in the control group (p = 0.04). The rate of LAM defect was significantly higher in the fundal pressure group (p = 0.001). The rate of loss of tenting was significantly higher in the fundal pressure group (p < 0.0001). According to multivariate regression models, the fundal pressure was the only independent factor associated with LAM defect (OR = 5.63; 95% CI = 12.01-15.74) and loss of tenting (OR = 8.74; 95% CI = 2.89-26.43).

CONCLUSIONS

Fundal pressure during the second stage of delivery is associated with a higher risk of LAM defect and loss of anterior vaginal wall support.

CLINICAL TRIAL REGISTRATION

NCT03752879.

Levator ani muscle coactivation at term is associated with longer second stage of labor in nulliparous women

OBJECTIVE

To assess the effect of levator ani muscle (LAM) coactivation at term on outcome of labor in nulliparous women.

METHODS

This was a prospective study of 284 low-risk nulliparous women with a singleton pregnancy at term recruited before the onset of labor. The anteroposterior diameter of the levator hiatus was measured in each woman on transperineal ultrasound at rest, on maximum pelvic floor muscle contraction and on maximum Valsalva maneuver before and after visual feedback. LAM coactivation was defined as a reduction in the anteroposterior diameter of the levator hiatus on maximum Valsalva maneuver in comparison with that at rest. The association of pelvic hiatal diameter values and LAM coactivation with mode of delivery and duration of labor was assessed.

RESULTS

No significant difference was found between women who underwent Cesarean delivery and those who had a vaginal delivery with regard to the anteroposterior diameter of the levator hiatus at rest, on pelvic floor muscle contraction and on Valsalva maneuver. Longer second stage of labor was associated with shorter anteroposterior diameter of the levator hiatus on all assessments, but in particular at rest and on Valsalva both before and after visual feedback. LAM coactivation was found in 89 (31.3%) and 75 (26.4%) women before and after visual feedback, respectively. Post visual feedback, women with LAM coactivation had a significantly longer second stage of labor than did those without LAM coactivation (83 ± 63 vs 63 ± 42 min; P = 0.006). On Cox regression analysis, LAM coactivation post visual feedback was an independent predictor of longer second stage of labor (adjusted hazard ratio, 1.499 (95% CI, 1.076-2.087); P = 0.017).

CONCLUSION

LAM coactivation in nulliparous women at term is associated with a longer second stage of labor. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Perineal ultrasound for the measurement of urethral mobility: a study of inter- and intra-observer reliability

INTRODUCTION AND HYPOTHESIS

Ultrasound measurement of urethral mobility is an attractive approach to directly visualize bladder neck descent (BND) during stress. BND assessed by transperineal ultrasound appears to be associated with stress urinary incontinence (SUI) severity. This study evaluated the inter- and intra-observer reliability of ultrasound BND measurement and its correlation with clinical examination.

METHODS

We included 50 women from the multicenter randomized 3PN study ("Prenatal Perineal Prevention"). BND was measured by two operators either during pregnancy (at 20 weeks of gestation) or 2 months after delivery. Two measurements were taken by each operator. Intra-class coefficient correlations were used for analysis. Urethral mobility was clinically assessed by measuring the point Aa of the POP-Q classification during maximum strain (Valsalva maneuver) with an empty bladder.

RESULTS

Ultrasound analysis showed high intra-observer reliability in the overall population: intraclass correlation coefficients (ICC) = 0.75 (0.59-0.85) and 0.73 (0.55-0.84) for each operator. Intra-observer agreements were considered moderate to high in the post- and antepartum groups. Inter-observer agreements were moderate in the antepartum period [ICC = 0.58 (0.26-0.78) for the first measurement and 0.68 (0.42-0.84) for the second] but low in the postpartum period [ICC = 0.15 (0.10-0.41) and 0.21 (0.10-0.58)]. Correlations between ultrasound and clinical measurements were considered low to moderate (Spearman coefficient, rho = 0.34 and 0.50 for post- and antepartum periods, respectively).

CONCLUSIONS

Inter-observer reliability of ultrasound urethral mobility measurements by the transperineal route is moderate antepartum and low postpartum. The correlation with point Aa is low to moderate.

Recommended standardized terminology of the anterior female pelvis based on a structured medical literature review

BACKGROUND

The use of imprecise and inaccurate terms leads to confusion amongst anatomists and medical professionals.

OBJECTIVE

We sought to create recommended standardized terminology to describe anatomic structures of the anterior female pelvis based on a structured review of published literature and selected text books.

STUDY DESIGN

We searched MEDLINE from its inception until May 2, 2016, using 11 medical subject heading terms to identify studies reporting on anterior female pelvic anatomy; any study type published in English was accepted. Nine textbooks were also included. We screened 12,264 abstracts, identifying 200 eligible studies along with 13 textbook chapters from which we extracted all pertinent anatomic terms.

RESULTS

In all, 67 unique structures in the anterior female pelvis were identified. A total of 59 of these have been previously recognized with accepted terms in Terminologia Anatomica, the international standard on anatomical terminology. We also identified and propose the adoption of 4 anatomic regional terms (lateral vaginal wall, pelvic sidewall, pelvic bones, and anterior compartment), and 2 structural terms not included in Terminologia Anatomica (vaginal sulcus and levator hiatus). In addition, we identified 2 controversial terms (pubourethral ligament and Grafenberg spot) that require additional research and consensus from the greater medical and scientific community prior to adoption or rejection of these terms.

CONCLUSION

We propose standardized terminology that should be used when discussing anatomic structures in the anterior female pelvis to help improve communication among researchers, clinicians, and surgeons.

Perineal body anatomy seen by three-dimensional endovaginal ultrasound of asymptomatic nulliparae

AIM

The perineal body (PB) plays an important role in supporting the pelvic floor and the posterior vaginal wall, but its attachments and relationships are still debated. This study aimed to assess the normal anatomy of the PB using high-resolution three-dimensional endovaginal ultrasound (3D-EVUS) in asymptomatic nulliparae.

METHOD

To validate the identification of perineal structures, 3D-EVUS was initially performed on nulliparous cadavers. Fresh frozen pelves were prepared and echogenic structures thought to be the PB, the external anal sphincter, the superficial and deep transverse perineii, pubovaginalis, puboperinealis, puboanalis, puborectalis and iliococcygeus muscles were tagged with biopsy needles, and marked with indigo carmine dye for localization during dissection. In the second part of the study, consecutive asymptomatic nulliparae were prospectively imaged with the same ultrasound modality. Interrater reproducibility was assessed off-line from stored 3D US volumes using a standardized technique.

RESULTS

Five fresh frozen pelves and 44 asymptomatic nulliparae were assessed with 3D-EVUS. The PB was seen as an ovoid structure of mixed echogenicity between the rectum and vagina. It appeared to be divided into a superficial level, in contact with the external anal sphincter, the bulbospongiousus and the superficial transverse perineii muscle and a deep level, in contact with puboperinealis and puboanalis muscles. Interobserver repeatability was excellent for the measurements of PB height [intraclass correlation coefficient (ICC) 0.927], PB depth (ICC 0.969) and PB width (ICC 0.932).

CONCLUSION

The PB is divided into two levels with different anatomical relationships with the pelvic floor muscles. 3D-EVUS yields reproducible assessment of this complex structure.

Live anatomy of the perineal body in patients with third-degree rectocele

AIM

In many pelvic floor disorders, the perineal body is damaged or destroyed. There is still a considerable variation in anatomical descriptions of the perineal body and even more debate with regard to its attachments and relationships. Cadaveric dissections do not always reflect the functional behaviour of structures in the pelvis and description of live anatomy on imaging studies is not always reliable. This study aimed to define the anatomy of the perineal body in patients with rectocele during the live dissection required for minimally invasive surgical repair.

METHOD

From January 2007 to December 2009 consecutive patients requiring surgery for third-degree rectocele and symptoms of obstructed defaecation were recruited. Participants underwent dissection of the perineal body, rectum and vagina preliminary to a tissue fixation system, an operation which inserts a tensioned tape to repair the perineal body.

RESULTS

Thirty Caucasian female patients, mean age 61 (range 47-87) years, mean parity 2.6 (range 1-5), were included. Live dissection demonstrated that the perineal body was divided into two parts, joined by a stretched central part, anchored laterally by the deep transverse perineii muscle to the descending ramus of the pubic bone. The mean longitudinal length of the perineal body was 4.5 (3.5-5.5) cm, accounting for 50% of the posterior vaginal support.

CONCLUSION

In women with low rectocele, the perineal body appears to be divided into two parts, severely displaced behind the ischial tuberosities.

Effect of age, body mass index, and parity on Pelvic Organ Prolapse Quantification system measurements in women with symptomatic pelvic organ prolapse

AIM

To evaluate the effect of age, body mass index (BMI), and parity on Pelvic Organ Prolapse Quantification (POP-Q) system measurements in women with symptomatic prolapse.

MATERIAL AND METHODS

The charts of 603 women with symptomatic prolapse were reviewed. Patients with prior prolapse surgery or hysterectomy were excluded. POP-Q measurements were recorded by a single examiner. Data were analyzed using descriptive statistics, the Pearson's product-moment correlation, and Wilcoxon signed rank test.

RESULTS

Three hundred and eleven patients met inclusion criteria. Mean age was 63.4 years, mean parity was 2.6, and mean body mass index (BMI) was 26.6 kg/m(2) . Increasing age was correlated with worsening scores on Ba (r = 0.33, P < 0.0001), C (r = 0.14, P < 0.02), D (r = 0.14, P = 0.02) and Bp (r = 0.13, P = 0.02), while parity was only correlated with worsening scores on Aa (r = 0.12, P = 0.04). There was no correlation between BMI and any POP-Q data point.

CONCLUSION

The effect of increasing parity was seen solely on point Aa in women with symptomatic prolapse. Age affected all vaginal compartments, while BMI had no impact on POP-Q data points.

Measuring the levator hiatus with axial MRI sequences: adjusting the angle of acquisition

AIMS

We aimed to compare MRI measurements of the female levator hiatus and the most caudal "levator ani" muscles between image slices in a plane axial to the body (AxB) and an axial plane parallel to the direction of the puborectalis muscle (AxPRM).

METHODS

We performed high-resolution, T2-weighted axial magnetic resonance imaging (in two different planes) on 20 sequentially recruited asymptomatic nulliparous women. Levator hiatus measurements were compared between the two planes.

RESULTS

The mean tilt angle of the AxPRM slices relative to the AxB slices was 18.9° (SD 8.5) and the area of the levator hiatus was 10% greater (P=0.04) in the AxPRM plane.

CONCLUSIONS

By rotating the acquisition plane to be parallel to the puborectalis muscle (sometimes called the plane of minimal hiatal dimensions), some of the measurements of the distal and medial pelvic floor muscles (and the hiatus defined by them) are altered. This issue is important because both MRI and 3D ultrasound are increasingly being used to evaluate the pelvic floor hiatus, and its relationship to childbirth injury and pelvic floor disorders. To make meaningful comparisons, it is important that both modalities are measuring the same thing.

Ultrasound imaging of the pelvic floor: where are we going?

We produced a non systematic review of ultrasound imaging of the pelvic floor in women with urinary incontinence (UI) and/or pelvic organ prolapse (POP). We have searched the PubMed and Embase databases for the following PICO question: women; imaging; urinary incontinence, pelvic organ prolapse, pelvic floor, pelvic floor muscle, pelvic floor muscle training; physical examination, no imaging; diagnosis, prognosis, outcome. The production of a systematic review was deemed impossible based on the type and quality of the published evidence. Clinical research focused on the pathophysiology of the UI and POP looking relation between anatomic abnormalities, childbirth, the risk of UI or POP, the outcome of conservative treatment and reconstructive surgery. Published papers fall into the remits of diagnostic studies but often fail to comply with the recommendations of the STARD initiative. Most published evidence remains the product of a single institution effort and confirmatory studies are rarely found. Imaging studies in patients with UI did not provide evidence of any clinical benefit in the management of patients. In patients with POP, interesting correlations have been identified such as between childbirth, dimension of levator hiatus, avulsion of levator ani and risk of prolapse, but the non clinical benefit of pelvic floor imaging could still not be identified. Research on pelvic floor imaging requires a coordinated, international, multicentre effort to improve internal and external validity of imaging techniques, confirm observations published by single institutions and provide health technology assessment of imaging in the management of UI or POP patients.

Three-dimensional ultrasound imaging

This review is about the development of three-dimensional (3D) ultrasonic medical imaging, how it works, and where its future lies. It assumes knowledge of two-dimensional (2D) ultrasound, which is covered elsewhere in this issue. The three main ways in which 3D ultrasound may be acquired are described: the mechanically swept 3D probe, the 2D transducer array that can acquire intrinsically 3D data, and the freehand 3D ultrasound. This provides an appreciation of the constraints implicit in each of these approaches together with their strengths and weaknesses. Then some of the techniques that are used for processing the 3D data and the way this can lead to information of clinical value are discussed. A table is provided to show the range of clinical applications reported in the literature. Finally, the discussion relating to the technology and its clinical applications to explain why 3D ultrasound has been relatively slow to be adopted in routine clinics is drawn together and the issues that will govern its development in the future explored.

Is sacral neuromodulation for fecal incontinence worthwhile in patients with associated pelvic floor injury?

PURPOSE

It has been shown that vaginal delivery may result in pelvic floor injury. Until now it is unknown whether this type of injury plays a role in the etiology of fecal incontinence and whether it affects the outcome of treatment. The aim of the present study was to assess the prevalence of pelvic floor injury in patients with fecal incontinence who were eligible for sacral neuromodulation and to determine whether sacral neuromodulation is worthwhile in patients with pelvic floor injury.

METHODS

All women with fecal incontinence who were eligible for sacral neuromodulation in the past were invited to participate in the present study. With transperineal ultrasound, which has been developed recently, pelvic floor integrity was examined in 46 of the 66 patients (70%). Follow-up was obtained from a standardized questionnaire.

RESULTS

Pelvic floor injury was found in 29 of the 46 participants (63%). No differences regarding the efficacy of sacral neuromodulation were found between patients with and those without pelvic floor injury. Successful test stimulation was obtained in 86% of the patients with pelvic floor injury and in 71% of the patients without pelvic type injury. After implantation of a definitive pulse generator, a successful outcome was found in 84% of the patients with pelvic floor injury and in 75% of the patients with an intact pelvic floor.

CONCLUSION

Pelvic floor injury is present in the majority of incontinent patients who were eligible for sacral neuromodulation. This type of injury seems to have no detrimental effect on the treatment outcome.

Anterior sphincteroplasty for fecal incontinence: is the outcome compromised in patients with associated pelvic floor injury?

INTRODUCTION

It has been shown that vaginal delivery may result not only in sphincter defects, but also in pelvic floor injury. However, the influence of this type of injury on the etiology of fecal incontinence and its treatment is unknown. The present study was aimed to assess the prevalence of pelvic floor injury in patients who underwent anterior sphincteroplasty for the treatment of fecal incontinence and to determine the impact of this type of injury on the outcome of this procedure.

METHODS

Women who underwent anterior sphincteroplasty in the past were invited to participate in the present study. With transperineal ultrasound, which has been developed recently, pelvic floor integrity was examined in 70 of 117 patients (60%). Follow-up was obtained from a standardized questionnaire.

RESULTS

The median time period between anterior sphincteroplasty and the current assessment was 106 (range, 15-211) months. Pelvic floor injury was diagnosed in 43 patients (61%). Despite the prior sphincteroplasty, an external anal sphincter defect was found in 20 patients (29%). Outcome did not differ, neither between patients with and those without pelvic floor injury, nor between patients with and those without an adequate repair. However, patients with an adequate repair and an intact pelvic floor did have a better outcome than patients with one or both abnormalities.

CONCLUSION

The majority of female patients with incontinence who were eligible for anterior sphincteroplasty have concomitant pelvic floor injury. Based on the present study, it seems unlikely that this type of injury itself has an impact on the outcome of anterior sphincteroplasty.

High-resolution three-dimensional endovaginal ultrasonography in the assessment of pelvic floor anatomy: a preliminary study

INTRODUCTION AND HYPOTHESIS

Our aim was to evaluate the morphological characteristics of the female pelvic floor that may be further elucidated with three-dimensional endovaginal ultrasonography (3D-EVUS).

METHODS

A consecutive series of 20 nulliparous females underwent 3D-EVUS. Measurements were determined according to pre-established criteria. Descriptive statistics and Spearman's correlation test were performed.

RESULTS

The levator hiatus (LH) was measured in the oblique plane parallel to the pubovisceral muscle. A positive correlation was found between LH area and age (p = 0.03). The anteroposterior diameter of the urogenital hiatus, measured in the axial plane tilted from the symphysis pubis to the ischiopubic rami, correlated with LH area (p = 0.008). No urethral rotations were observed in the coronal plane. Significant correlations were found among urethral parameters. Mean anal sphincter measurements were comparable to previously reported magnetic resonance imaging and ultrasound measurements.

CONCLUSIONS

3D-EVUS allows measurements of key pelvic floor structures in planes that cannot be determined by conventional imaging modalities.

Three-dimensional transperineal ultrasonography of the pelvic floor: improving visualization for new clinical applications and better functional assessment

OBJECTIVE

With increasing awareness of the scope of pelvic floor disorders has come development and introduction into clinical practice of new imaging techniques, with increasing importance of ultrasonography. Complex pelvic floor anatomy, the conceptual difficulty in the basics of some pelvic floor disorders, and the uneven standardization of ultrasonographic techniques were the impetuses of this review. The purpose of this study was to review the basic anatomy of the pelvic floor and the transperineal ultrasonographic evaluation technique and to provide an overview of the current clinical use of 3-dimensional transperineal ultrasonography in the evaluation of the anterior and posterior pelvic floor compartments.

METHODS

A literature review illustrated with index cases from our center was conducted.

RESULTS

Ultrasonography has been widely applied to evaluation of the anterior and posterior compartments of the pelvic floor. Three-dimensional ultrasonography has a role in improving pelvic floor assessment.

CONCLUSIONS

Three-dimensional transperineal ultrasonography has been applied to evaluation of normal and pathologic pelvic floor anatomy. Practical application, through well-designed and sufficiently powered clinical studies, will establish the association between the clinical presentations of dysfunction with ultrasonographic findings.

Bilateral avulsion of the puborectal muscle: magnetic resonance imaging-based three-dimensional reconstruction and comparison with a model of a healthy nulliparous woman

OBJECTIVES

Obstetric trauma to the puborectal muscle seems to be an important cause of pelvic floor dysfunction in women. Due to the complicated three-dimensional (3D) arrangement of the pelvic structures, two-dimensional images are not sufficient to demonstrate its relationships in a complex fashion. Thus, we aimed to create a 3D computer model to visualize the normal female pelvic floor anatomy and to compare this with the anatomy after bilateral avulsion of the puborectal muscle following delivery.

METHODS

We created two 3D computer models of the female pelvic floor, one of a healthy nulliparous woman and the other of a woman with bilateral puborectal muscle avulsion after vaginal delivery. The data for the models were obtained from magnetic resonance imaging examinations and the following structures were depicted: pelvic bones, puborectal muscle, internal obturator muscle, urethra, urinary bladder, vagina and rectum. The models were compared.

RESULTS

The models allowed us to demonstrate in three dimensions changes in the puborectal muscle after avulsion. Its relations to the bone, internal obturator muscle, perineal membrane and the deep part of the external anal sphincter were modeled and differences from the normal non-injured anatomy were demonstrated. Avulsion altered the support to the whole endopelvic fascia and destabilized both the anterior and the posterior vaginal walls.

CONCLUSIONS

The use of 3D technology including modeling allows for the acquisition of new knowledge and aids in the understanding of both normal and pathological pelvic anatomy.

Postpartum evaluation of the anal sphincter by transperineal three-dimensional ultrasound in primiparous women after vaginal delivery and following surgical repair of third-degree tears by the overlapping technique

OBJECTIVE

Intrapartum damage to the anal sphincter is an important factor in fecal incontinence. Recognized lacerations occur in 0.36-8.4% of vaginal deliveries, and occult sphincter damage in up to 35% of primiparous women. We examined the role of three-dimensional transperineal ultrasound (3DTUS) in the evaluation of the anal sphincter in primiparous women after vaginal delivery and after surgical repair of third-degree intrapartum tears by the overlapping technique.

METHODS

During 2004-2005 139 primiparous women without clinically recognized third- to fourth-degree anal sphincter tears were prospectively studied 24-72 h postpartum (Group 1) and 13 primiparous women were examined 48 h to 4 months following surgical repair of third-degree tears with the overlapping technique (Group 2). A 3D 5-9-MHz transvaginal probe was placed in the area of the fourchette and perineal body in transverse and sagittal planes and 2-4 volumes were stored. The parameters studied were: examination duration; continuity of the internal and external sphincters; occult sphincter damage; internal sphincter and external sphincter width-measured 1.5 cm from the distal margin of the anus-at the '12, 3, 6 and 9 o'clock positions'; length of the posterior internal sphincter.

RESULTS

Scanning was possible in all women and the stored volumes were adequate in 127/139 (91.4%) cases. Mean examination time was 3.5 min. In Group 1, occult sphincter defect was suspected in 10/127 women (7.9%). These patients were excluded from measurement calculations, leaving 117 cases for analysis. The internal sphincter was consistently visualized in all the remaining patients (n = 117), while the external sphincter was fully visualized in 99/117 women (84.6%), and partially visualized in the remainder. Mean internal sphincter thickness was 2.60, 2.55, 2.60 and 2.72 mm at the 12, 3, 6 and 9 o'clock positions, respectively, and mean internal sphincter length was 3.34 cm. Mean external sphincter thickness was 4.15, 4.20, 4.21 and 4.20 mm at the 12, 3, 6 and 9 o'clock measurement points. In Group 2, 3DTUS confirmed anatomic abnormalities in all the women in the area surrounding the 12 o'clock position. Evaluation of sphincter tears and their position and length was possible using the longitudinal view. Thinning of the internal sphincter in the area of damage and thickening on the opposite side, the 'half moon sign', sphincter discontinuity, thickening of the external sphincter in the area of repair and abnormality of mucous folds, seemed to be common signs of third-degree intrapartum sphincter tears, even after repair.

CONCLUSIONS

3DTUS is an accessible and promising method for postpartum sphincter evaluation, that is apparently well tolerated by patients. Reference data for sphincter anatomy representative of findings at transperineal ultrasound in primiparous women in the postpartum period have been established.

Location of spina bifida occulta and ultrasonographic bladder abnormalities predict the outcome of treatment for primary nocturnal enuresis in children

OBJECTIVE

We examined whether the existence of spina bifida occulta or ultrasonographic bladder abnormalities was related to the outcome of treatment for primary nocturnal enuresis in children.

METHODS

Between April 1996 and September 2005, a total of 77 subjects (53 boys and 24 girls, aged 5-18 years; mean age, 9.9 years) with primary nocturnal enuresis were studied. Plain X-ray films of the spine and ultrasonographic bladder measurements (bladder wall thickness, bladder neck descent and bladder neck opening) were obtained and the correlations with the outcome of treatment using imipramine hydrochloride were assessed.

RESULTS

On plain X-ray films of the spine, spina bifida occulta (lumbar vertebrae in three, lumbosacral vertebrae in 19 and sacral vertebrae in 31) was recognized in 53 children (69%). Ultrasonographic bladder abnormalities were recognized in 40 children (52%). Children with lumbar and lumbosacral spina bifida occulta showed a higher rate of concomitant ultrasonographic bladder abnormalities (P = 0.006) and had a poorer response to treatment (P = 0.041) compared with the children who had sacral spina bifida occulta. Children with ultrasonographic bladder abnormalities had a worse response to treatment (P = 0.005) compared to the children without bladder abnormalities.

CONCLUSIONS

The presence of lumbar spina bifida occulta and ultrasonographic bladder abnormalities was related to the outcome of treatment for primary nocturnal enuresis in children, suggesting that spinal radiography and vesical ultrasonography may be useful predictive tests.

New postnatal urinary incontinence: obstetric and other risk factors in primiparae

OBJECTIVE

To identify obstetric and other risk factors for urinary incontinence that occurs during pregnancy or after childbirth.

DESIGN

Questionnaire survey of women.

SETTING

Maternity units in Aberdeen (Scotland), Birmingham (England) and Dunedin (New Zealand).

POPULATION

A total of 3405 primiparous women with singleton births delivered during 1 year.

METHODS

Questionnaire responses and obstetric case note data were analysed using multivariate analysis to identify associations with urinary incontinence.

MAIN OUTCOME MEASURES

Urinary incontinence at 3 months after delivery first starting in pregnancy or after birth.

RESULTS

The prevalence of urinary incontinence was 29%. New incontinence first beginning after delivery was associated with older maternal age (oldest versus youngest group, OR 2.02, 95% CI 1.35-3.02) and method of delivery (caesarean section versus spontaneous vaginal delivery, OR 0.28, 95% CI 0.19-0.41). There were no significant associations with forceps delivery (OR 1.18, 95% CI 0.92-1.51) or vacuum delivery (OR 1.16, 95% CI 0.83-1.63). Incontinence first occurring during pregnancy and still present at 3 months was associated with higher maternal body mass index (BMI>25, OR 1.68, 95% CI 1.16-2.43) and heavier babies (birthweight in top quartile, OR 1.56, 95% CI 1.12-2.19). In these women, caesarean section was associated with less incontinence (OR 0.39, 95% CI 0.27-0.58) but incontinence was not associated with age.

CONCLUSIONS

Women have less urinary incontinence after a first delivery by caesarean section whether or not that first starts during pregnancy. Older maternal age was associated with new postnatal incontinence, and higher BMI and heavier babies with incontinence first starting during pregnancy. The effect of further deliveries may modify these findings.

Three- and 4-dimensional ultrasound in obstetrics and gynecology: proceedings of the American Institute of Ultrasound in Medicine Consensus Conference

The American Institute of Ultrasound in Medicine convened a panel of physicians and scientists with interest and expertise in 3-dimensional (3D) ultrasound in obstetrics and gynecology to discuss the current diagnostic benefits and technical limitations in obstetrics and gynecology and consider the utility and role of this type of imaging in clinical practice now and in the future. This conference was held in Orlando, Florida, June 16 and 17, 2005. Discussions considered state-of-the-art applications of 3D ultrasound, specific clinical situations in which it has been found to be helpful, the role of 3D volume acquisition for improving diagnostic efficiency and patient throughput, and recommendations for future investigations related to the utility of volume sonography in obstetrics and gynecology.

Evidence for the Innervation of Pelvic Floor Muscles by the Pudendal Nerve

OBJECTIVE

To evaluate whether the pudendal nerve innervates the levator ani muscles by assessing the effect of pudendal nerve blockade on pelvic floor muscle function.

METHODS

Eleven nulliparous women without symptoms of anal or urinary incontinence were studied before and after pudendal nerve blockade with vaginal manometry, electromyography of the external anal sphincter and puborectalis muscle, and 3-dimensional transperineal ultrasound imaging of the urogenital hiatus during rest and squeeze.

RESULTS

After pudendal nerve blockade, mean vaginal resting pressures decreased from 19 +/- 10 mm Hg to 15 +/- 10 mm Hg (P < .05), and mean vaginal squeeze pressures decreased from 61 +/- 29 mm Hg to 37 +/- 24 mm Hg (P < .05). After pudendal nerve blockade, the anterior-posterior length of the urogenital hiatus increased from 51 +/- 4 mm to 55 +/- 5 mm at rest (P < .05) and increased from 47 +/- 3 mm to 52 +/- 5 mm during squeeze (P < .05). Resting and squeeze electromyography amplitude of the external anal sphincter and puborectalis muscle was markedly reduced by pudendal nerve blockade.

CONCLUSION

Pudendal nerve blockade decreases vaginal pressures, increases length of urogenital hiatus, and decreases electromyography activity of the puborectalis muscle, all of which suggest that the pudendal nerve does innervate the levator ani muscle.

Pelvic floor trauma in childbirth - myth or reality?

The issue of traumatic damage to the pelvic floor in childbirth is attracting more and more attention amongst obstetric caregivers and laypersons alike. This is partly due to the fact that elective Caesarean section, as a potentially preventative intervention, is increasingly available and perceived as safe. As there are a multitude of emotive issues involved, including health economics and the relative roles of healthcare providers, the discussion surrounding pelvic floor trauma in childbirth has not always been completely rational. However, after 25 years of urogynaecological research in this field it should be possible to determine whether pelvic floor trauma in childbirth is myth or reality. On reviewing the available evidence, it appears that there are sufficient grounds to assume that vaginal delivery (or even the attempt at vaginal delivery) can cause damage to the pudendal nerve, the caudal aspects of the levator ani muscle, fascial pelvic organ supports and the external and internal anal sphincter. Risk factors for such damage have been defined and variously include operative vaginal delivery, a long second stage, and macrosomia. It is much less clear, however, whether such trauma is clinically relevant, and how important it is in the aetiology of pelvic floor morbidity later in life.

Biometry of the pubovisceral muscle and levator hiatus by three-dimensional pelvic floor ultrasound

OBJECTIVE

Until recently, magnetic resonance was the only imaging method capable of assessing the levator ani in vivo. Three-dimensional (3D) ultrasound has recently been shown to be able to demonstrate the pubovisceral muscle. The aim of this study was to define the anatomy of the levator hiatus in young nulliparous women with the help of 3D ultrasound.

METHODS

In a prospective observational study, 52 nulligravid female Caucasian volunteers (aged 18-24 years) were assessed by two-dimensional (2D) and 3D translabial ultrasound after voiding whilst supine. Pelvic organ descent was assessed on Valsalva maneuver. Volumes were acquired at rest and on Valsalva maneuver, and biometric indices of the pubovisceral muscle and levator hiatus were determined in the axial and coronal planes.

RESULTS

In the axial plane, average diameters of the pubovisceral muscle were 0.4-1.1 cm (mean 0.73 cm). Average area measurements were 7.59 (range, 3.96-11.9) cm2. The levator hiatus at rest varied from 3.26 to 5.84 (mean 4.5) cm in the sagittal direction, and from 2.76 to 4.8 (mean 3.75) cm in the coronal plane. The hiatus area at rest ranged from 6.34 to 18.06 (mean 11.25) cm2 increasing to 14.05 (6.67-35.01) cm(2) on Valsalva maneuver (P = 0.009). There were significant correlations between pelvic organ mobility and hiatus area at rest (P = 0.018 to P < 0.001) and on Valsalva maneuver (all P < 0.001).

CONCLUSIONS

Biometric indices of the pubovisceral muscle and levator hiatus can be determined by 3D ultrasound. Significant correlations exist between hiatal area and pelvic organ descent. These data provide support for the hypothesis that levator ani anatomy plays an independent role in determining pelvic organ support.

Paravaginal defects: a comparison of clinical examination and 2D/3D ultrasound imaging

BACKGROUND

Paravaginal defects are often assumed to be the underlying anatomical abnormality in anterior compartment descent. Neither clinical examination nor ultrasound assessment are generally accepted diagnostic modalities.

AIMS

To compare clinical examination and translabial 3D ultrasound in the detection of such defects.

METHODS

Fifty-nine women without previous prolapse or incontinence surgery were seen prospectively. Clinical and ultrasound assessments were carried out in blinded fashion. 3D translabial ultrasound was undertaken after voiding and supine. Volumes were acquired at rest, on Valsalva and on levator contraction. Loss of paravaginal support ('tenting') in the axial plane was taken to signify paravaginal defects.

RESULTS

Paravaginal defects were reported clinically in 14 cases on the left (24%), 19 times on the right (32%). Two 3D ultrasound examinations did not yield satisfactory volumes, leaving 57 for analysis. Neither midsagittal nor coronal views yielded data that correlated with clinical assessments. In the axial plane there was absence of tenting at rest in 32/57 (57%) patients, but this did not correlate with clinical findings. Loss of tenting on Valsalva was observed less often (21/57, 37%) and was weakly associated with clinically observed lateral defects (P = 0.036).

CONCLUSIONS

Pelvic floor ultrasound in midsagittal, axial or coronal planes does not correlate well with clinical assessment for paravaginal defects. This could be due to poor clinical assessment technique or limitations of the ultrasound method. On the other hand, paravaginal defects may be uncommon or clinically irrelevant. On present knowledge, the paravaginal defect has to be regarded as an unproven concept.

The use of ultrasound imaging of the abdominal drawing-in maneuver in subjects with low back pain

STUDY DESIGN

Randomized controlled trial among patients with low back pain (LBP).

OBJECTIVES

(1) Determine the reliability of real-time ultrasound imaging for assessing activation of the lateral abdominal muscles; (2) characterize the extent to which the abdominal drawing-in maneuver (ADIM) results in preferential activation of the transverse abdominis (TrA); and (3) determine if ultrasound biofeedback improves short-term performance of the ADIM in patients with LBP.

BACKGROUND

Ultrasound imaging is reportedly useful for measuring and training patients to preferentially activate the TrA muscle. However, research to support these claims is limited.

METHODS AND MEASURES

Thirty patients with LBP referred for lumbar stabilization training were randomized to receive either traditional training (n = 15) or traditional training with biofeedback (n = 15). Ultrasound imaging was used to measure changes in thickness of the lateral abdominal muscles. Differences in preferential changes in muscle thickness of the TrA between groups and across time were assessed using analysis of variance.

RESULTS

Intrarater reliability measuring lateral abdominal muscle thickness exceeded 0.93. On average, patients in both groups demonstrated a 2-fold increase in the thickness of the TrA during the ADIM. Performance of the ADIM did not differ between the groups.

CONCLUSION

These data provide construct validity for the notion that the ADIM results in preferential activation of the TrA in patients with LBP. Although, the addition of biofeedback did not enhance the ability to perform the ADIM at a short-term follow-up, our data suggest a possible ceiling effect or an insufficient training stimulus. Further research is necessary to determine if there is a subgroup of patients with LBP who may benefit from biofeedback.

Visualization of the endopelvic fascia by transrectal three-dimensional ultrasound

The aim of our pilot study was to explore the feasibility of visualizing the endopelvic fascia by transrectal three-dimensional (3D) ultrasound. Transrectal 3D ultrasound was performed in 12 nulliparous women and 11 women with a history of vaginal delivery. A 6-10 MHz volume probe was used to examine the suburethral anterior vaginal wall. In all women, an echogenic layer was identified at an average of 3-5 mm from the vaginal surface. This echogenic layer was found to be contiguous to the lateral pelvic sidewall and uninterrupted in 10 of 12 nulliparous women, whereas gaps in this layer were identified in all 11 parous women. We hypothesize that this echogenic layer may represent the suburethral component of the endopelvic fascia. Depending on the number and localization of the interruptions in this echogenic layer, the mechanical support of the pelvic floor seems to be weakened corresponding to a higher incidence of descensus of the anterior vaginal wall, which frequently was associated with urinary incontinence.

Ultrasound imaging of the pelvic floor. Part II: three-dimensional or volume imaging

In this second part of a review of pelvic floor ultrasound imaging, current three-dimensional (3D) ultrasound technology and its use for imaging pelvic floor structure and function is described. Recent technical developments enable rapid automated volume acquisition in real time, and currently available transducers designed for abdominal use are well suited for translabial/transperineal imaging. To date, such systems have been used to image the urethra, the levator ani and paravaginal supports, prolapse and implants used in pelvic floor reconstruction and anti-incontinence surgery. While 3D pelvic floor imaging is a field that is still in its infancy, it is already clear that the method has opened up entirely new opportunities for the observation of functional anatomy.

The 'iris effect': how two-dimensional and three-dimensional ultrasound can help us understand anti-incontinence procedures

OBJECTIVE

The objective of this prospective, observational study in patients after tension-free vaginal tape (TVT) implantation was to describe the spatial relationship between suburethral sling implants, urethra and bony pelvis with the help of translabial two-dimensional and three-dimensional (3D) ultrasound.

METHODS

A total of 141 women were examined by translabial ultrasound, supine and after voiding. The TVT sling is highly echogenic and easily identified posterior to the urethra. Tape location was described in the mid-sagittal plane relative to bladder neck and inferoposterior symphyseal margin, at rest and on Valsalva maneuver. In a subset of 83 women, 3D volume ultrasound was performed.

RESULTS

The cranial tape margin was situated on average 9.3 mm above and 16.5 mm posterior to the symphyseal margin (Valsalva: 3.9 mm below and 9.6 mm behind the symphysis); the average tape movement on Valsalva was 16 (range, 2-34.2) mm. The distance between tape and inferoposterior symphyseal margin narrowed highly significantly from 20.4 +/- 4.3 mm at rest to 12.9 +/- 3.9 mm on Valsalva (P < 0.001). When a fitted line plot was placed through tape coordinates on an x-y coordinate system, it became evident that tape movement occurs in an arc around the fulcrum of the posterior symphysis pubis. The result is an increasing reduction in the gap between tape and symphysis pubis (termed the 'iris effect'), implying mechanical compression of the urethra.

CONCLUSIONS

The curative effect of the TVT on stress incontinence is likely to be due to mechanical compression of the urethra between implant and symphysis pubis. A large variation in tape location and movement explains its wide margin of clinical safety and efficacy.