State of the art: an integrated approach to pelvic floor ultrasonography

The value of pre-operative multicompartment pelvic floor ultrasonography: a 1-year prospective study

OBJECTIVE

Comprehensive assessment of the pelvic floor (PF) provides information and diagnoses of coexisting abnormalities that may affect operative decisions. Our aim was to establish if pre-operative PF ultrasonography (PFUS) in patients complaining of PF dysfunction can complement clinical findings and contribute to additional management strategies.

METHODS

Females were recruited from the urogynaecology/gynaecology clinics between July and October 2009 and underwent pelvic organ prolapse quantification (POPQ) by an independent examiner. PFUS was performed using two-dimensional (2D) transperineal ultrasound (TPUS), high-frequency 2D/three-dimensional (3D) endovaginal ultrasound (EVUS) using a biplane probe with linear and transverse arrays and a 360° rotational 3D-EVUS. The clinician performing PFUS was blinded to POPQ results. POPQ and PFUS were repeated at 1 year. Two clinicians analysed the scans independently.

RESULTS

158 of 160 females had a POPQ and PFUS. 105 females had pelvic organ prolapse and/or incontinence and 53 asymptomatic females were controls. 26 additional ultrasound diagnoses were noted at baseline and 46 at 1 year using 2D-TPUS and EVUS. Only one female with additional diagnoses on PFUS needed surgical intervention for this condition.

CONCLUSION

Multicompartment PFUS identifies additional conditions to that diagnosed on clinical assessment. However, it neither changes the initial surgical management nor the management at 1-year follow-up and therefore clinical assessment should not be substituted by PFUS.

ADVANCES IN KNOWLEDGE

PFUS can be helpful in providing additional information; however, it does not change the initial management of the patient and therefore should not replace clinical assessment.

Imaging of slings and meshes

The popularity of imaging in pelvic floor medicine continues to increase. Among the various modalities, ultrasound is superior as it is cheap, safe, easily accesible and simple, resulting in high patient compliance. It is the only technique that allows imaging of modern wide-weave polypropylene sling or mesh implants, and imaging of such implants is commonly required due to the popularity of surgical techniques that involve the placement of slings and meshes. This review article will discuss the role of translabial ultrasound in the evaluation of synthetic implants used in the treatment of urinary incontinence and pelvic organ prolapse.

Three-dimensional saline infusion vaginography for sonographic assessment of the anterior vaginal wall and pelvic floor descent

Ultrasound has been recognized as an important tool for pelvic floor evaluation. A main limitation of the two-dimensional transvaginal examination is in delineation of the posterior vaginal compartment and its relation to the cervix. We describe the use of three-dimensional saline infusion vaginography as a complementary technique for the assessment of the vaginal wall and pelvic floor descent. We present several cases that demonstrate the advantages of this technique in overcoming the limitations inherent in current approaches. The improved imaging obtained by this technique enabled us to measure pelvic floor parameters and assist in evaluating pelvic floor dysfunction.

Use of dynamic 3-dimensional transvaginal and transrectal ultrasonography to assess posterior pelvic floor dysfunction related to obstructed defecation

BACKGROUND

New ultrasound techniques may complement current diagnostic tools, and combined techniques may help to overcome the limitations of individual techniques for the diagnosis of anorectal dysfunction. A high degree of agreement has been demonstrated between echodefecography (dynamic 3-dimensional anorectal ultrasonography) and conventional defecography.

OBJECTIVE

Our aim was to evaluate the ability of a combined approach consisting of dynamic 3-dimensional transvaginal and transrectal ultrasonography by using a 3-dimensional biplane endoprobe to assess posterior pelvic floor dysfunctions related to obstructed defecation syndrome in comparison with echodefecography.

DESIGN AND SETTING

This was a prospective, observational cohort study conducted at a tertiary-care hospital.

PATIENTS

Consecutive female patients with symptoms of obstructed defecation were eligible.

INTERVENTION

Each patient underwent assessment of posterior pelvic floor dysfunctions with a combination of dynamic 3-dimensional transvaginal and transrectal ultrasonography by using a biplane transducer and with echodefecography.

MAIN OUTCOME MEASURES

Kappa (κ) was calculated as an index of agreement between the techniques. Diagnostic accuracy (sensitivity, specificity, and positive and negative predictive values) of the combined technique in detection of posterior dysfunctions was assessed with echodefecography as the standard for comparison.

RESULTS

A total of 33 women were evaluated. Substantial agreement was observed regarding normal relaxation and anismus. In detecting the absence or presence of rectocele, the 2 methods agreed in all cases. Near-perfect agreement was found for rectocele grade I, grade II, and grade III. Perfect agreement was found for entero/sigmoidocele, with near-perfect agreement for rectal intussusception. Using echodefecography as the standard for comparison, we found high diagnostic accuracy of transvaginal and transrectal ultrasonography in the detection of posterior dysfunctions.

LIMITATIONS

This combined technique should be compared with other dynamic techniques and validated with conventional defecography.

CONCLUSIONS

Dynamic 3-dimensional transvaginal and transrectal ultrasonography is a simple and fast ultrasound technique that shows strong agreement with echodefecography and may be used as an alternative method to assess patients with obstructed defecation syndrome.

Perineal body repair in patients with third degree rectocele: a critical analysis of the tissue fixation system

AIM

We describe the technique of tissue fixation system (TFS) perineal body repair in patients presenting with symptomatic third degree rectocele.

METHOD

The single sling TFS perineal body repair is performed in three surgical steps: (i) dissection of the rectum off the vagina and laterally displaced perineal body; (ii) identification of the deep transverse perineii muscles beyond their insertion point behind the descending pubic ramus; (iii) elevation and approximation of the separated and laterally displaced perineal bodies by insertion, without tension, of non-stretch 7 mm polypropylene tape into the bodies of the deep transverse perineii muscles.

RESULTS

From January 2007 to December 2009 we performed the TFS operation for 30 women, median age 61 (range 47-87) years, mean parity 2.6 (range 1-5), with third degree symptomatic low rectocele (median obstructive defaecation syndrome score 19; range 11-24). Median hospital stay was 24 (range 12-96) h. The median visual analogue scale for postoperative pain was 1 (range 1-7). Complications occurred in three cases (10%) and included a surfaced tape that was partly resected (repair maintained), a recurrence of the rectocele due to incorrect placement (failed repair) and a foreign body abscess requiring tape removal. At 12-month follow-up, 27 patients (90%) reported normal defaecation and the median obstructive defaecation syndrome score was significantly reduced to 4 (range 1-6; P < 0.001).

CONCLUSION

The TFS perineal body repair is an effective, safe, minimally invasive treatment in women with symptomatic low rectocele.

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.

Anatomical disruption and length-tension dysfunction of anal sphincter complex muscles in women with fecal incontinence

BACKGROUND

Anal sphincter complex muscles, the internal anal sphincter, external anal sphincter, and puborectalis muscles, play an important role in the anal continence mechanism. Patients with symptoms of fecal incontinence have weak anal sphincter complex muscles; however, their length-tension properties and relationship to anatomical disruption have never been studied.

OBJECTIVE

This study aimed to assess the anatomy of the anal sphincter complex muscles with the use of a 3-dimensional ultrasound imaging system and to determine the relationship between the anatomical defects and the length-tension property of external anal sphincter and puborectalis muscles in women with incontinence symptoms and in control subjects.

DESIGN

Severity of anal sphincter muscle damage was determined by static and dynamic 3-dimensional ultrasound imaging. The length-tension property was determined by anal and vaginal pressure with the use of custom-designed probes.

PATIENTS

Forty-four asymptomatic controls and 24 incontinent patients participated in this study.

MAIN OUTCOME MEASURES

The anatomical defects and length-tension dysfunction of anal sphincter complex muscles in patients with fecal incontinence were evaluated.

RESULTS

The prevalence of injury to sphincter muscles is significantly greater in the incontinent patients than in the controls. Eighty-five percent of patients but only 9% controls reveal damage to ≥2 of the 3 muscles of the anal sphincter complex. Anal and vaginal squeeze pressures increased with the increase in the probe size (length-tension curve) in the majority of controls. In patients, the increase in anal and vaginal squeeze pressures was either significantly smaller than in controls or it decreased with the increasing probe size (abnormal length-tension).

LIMITATIONS

We studied patients with severe symptoms. Whether our findings are applicable to patients with mild to moderate symptoms remains to be determined.

CONCLUSIONS

The length-tension property of the external anal sphincter and puborectalis muscles is significantly impaired in incontinent patients. Our findings have therapeutic implications for the treatment of anal incontinence.

Imaging of Urethral Bulking Agents

Urethral bulking is an office procedure for treatment of stress urinary incontinence that has increased in popularity in recent years. Numerous types of urethral bulking agents have been used since its introduction in the 1930s. Typically, these agents are imaged using specialty 3D 360° field-of-view transducers; however, a sonographer, during a pelvic or renal examination, may inadvertently find and image an echogenic structure near the urethrovesical junction in patients with a history of urethral bulking. Familiarizing oneself with the sonographic appearance of urethral bulking agents and optimizing techniques to obtain improved images of these agents may eliminate the need for additional imaging for the patient. Urethral bulking can be readily imaged with transducers commonly found in most ultrasound departments. This review will focus on the sonographic characteristics of urethral bulking agents and knowing when and how to use appropriate transducers to image the urethra.

[Pelvic floor disorders from the surgeon's viewpoint]

Pelvic floor disorders present very differently with regard to symptoms and manifestation. Both diagnostic and treatment options require specific experience and an interdisciplinary approach. Diagnostic work-up is primarily based on medical history, physical examination and procto-rectoscopy. Furthermore, endosonography and perineal sonography have also gained importance. In almost all cases following these basic examinations conservative therapy options should be considered. As the interdisciplinary concept is very important, for careful diagnosis of pelvic floor disorders it became crucial to find an adequate form of treatment. Every decision for surgical therapy should not only focus on the results of previous examinations but should also consider the individual situation of each patient. In pelvic floor disorders a large variety of symptoms are confronted with a vast number of different and often highly specific procedures. The decisions on who to treat and how to treat are not only based on individual patient requests and desires but also on the experience and preference of the surgeon.

Inter- and intraobserver reliability for diagnosing levator ani changes on magnetic resonance imaging

OBJECTIVES

To assess the inter- and intraobserver reliability of the diagnosis of pubovisceral muscle avulsions and measurements of the levator hiatus on magnetic resonance imaging (MRI).

METHODS

Women with recurrent pelvic organ prolapse or in whom there was a discrepancy between clinical signs and symptoms of pelvic floor dysfunction underwent MRI and were eligible for inclusion. MRI datasets of the pelvic floor of 262 women were obtained and evaluated by two observers, who scored the presence and extent of pubovisceral muscle avulsions on each side using a scale from 0 to 3 and obtained measurements of the anteroposterior and transverse diameters and area of the levator hiatus. A random sample of 100 patients was reviewed a second time by one of the observers. Intraclass correlation coefficients (ICCs) with their 95% CI were calculated for all measurements. Mean differences with accompanying limits of agreement were calculated to estimate agreement between pairs of measurements and to detect possible systematic bias.

RESULTS

Good interobserver reliability was found for the assessment of pubovisceral muscle avulsions (ICC = 0.76-0.79) and excellent agreement for measurements of the levator hiatus (ICC = 0.85-0.89). The intraobserver reliability for pubovisceral muscle avulsions and other levator hiatus measurements was also excellent (ICC = 0.80-0.97). A significant interobserver systematic bias was observed in the measurement of levator hiatus transverse diameter; however, narrow limits of agreement were observed.

CONCLUSIONS

Pubovisceral muscle avulsions and levator hiatus measurements can be assessed with good to excellent reliability on MRI.

Two-/three-dimensional transperineal sonography of complicated tape and mesh implants

Transperineal sonography (TPS) affords dynamic evaluation of suburethral slings using tensionless vaginal tape and mesh implants used to treat complications associated with surgical procedures of the pelvic floor. This review describes and illustrates the TPS findings in postoperative complications such as recurrent prolapse, cystocele, enterocele, and rectocele. The potential use of live 3-dimensional TPS to delineate the dynamics aspects of pelvic floor disorder is also mentioned.

The treatment of anal fistulas with biologically derived products: is innovation better than conventional surgical treatment? An update

New technical approaches involving biologically derived products have been applied in the treatment for anal fistulas in order to avoid the risk of fecal incontinence. The aim of this review was to evaluate the scientific evidence present in the literature regarding these techniques. Trials comparing surgery (fistulotomy, advancement mucosal flap closure and placement of seton) versus fibrin glue, fistula plug or acellular dermal matrix were considered. In fibrin glue versus traditional surgical treatment the healing rate was higher in the surgery group, and the recurrence rate was lower in the traditional surgery group, but these results were not statistically relevant. In acellular dermal matrix (ADM) versus traditional surgical treatment the recurrence rate of fistulas was significantly lower in the ADM group, but non-significant differences were recorded in incontinence and anal deformity. Our review shows that there are no significant advantages of the new techniques involving biologically derived products. Further randomized controlled trials are needed.

The determinants of minimal levator hiatus and their relationship to the puborectalis muscle and the levator plate

OBJECTIVE

To determine the muscles comprising the minimal levator hiatus.

DESIGN

Cross-sectional study.

SETTING

The University of Oklahoma Health Sciences Center, USA.

POPULATION

Eight female fresh frozen pelves and 80 nulliparouswomen.

METHODS

Three-dimensional endovaginal ultrasound was performed in eight fresh frozen female pelves. The structures of the levator hiatus were tagged with needles and the cadavers were dissected to identify the tagged structures. A group of 80 nullipara underwent 3D endovaginal ultrasound, and the minimal levator hiatus area, puborectalis area, and anorectal angle were assessed, and normal values were obtained.

MAIN OUTCOME MEASURES

Anatomic borders of minimal levator hiatus and normality in pelvic floor measurements.

RESULTS

The pubococcygeus forms the inner lateral border and anterior attachment of the minimal levator hiatus to the pubic bone. The puboanalis fibres are immediately lateral to pubococcygeus attachments. There are variable contributions of the puborectalis fibres lateral to the puboanalis attachment. The posterior border of the minimal levator hiatus is formed by the levator plate. Eighty community-dwelling nulliparous women underwent 3D endovaginal ultrasound. The median age was 47 years (range 22-70 years). The mean of minimal levator hiatus and puborectalis hiatus areas were 13.4 cm(2) (±1.89 cm(2) SD) and 14.8 cm(2) (±2.16 cm(2) SD). The mean anorectal and levator plate descent angles were 156° (±10.04° SD) and 15.9° (±8.28° SD).

CONCLUSION

Anterior and lateral borders of the minimal levator hiatus are formed mostly by pubococcygeus. The puborectalis, pubococcygeus, and iliococcygeus form the bulk of the levator plate.

Diagnostic value of pelvic floor ultrasound in constipation due to female pelvic floor dysfunction

Constipation caused by female pelvic floor dysfunction (FPFD) is closely related to pathological changes in the front, middle and back basins. Constipation caused by pathological changes in the back basin manifests itself as rectocele, internal rectal intussusception, enterocele, descending perineum, and pelvic floor dyssynergia. Constipation due to the pathological changes in the front and middle basins not only manifests the above symptoms but also exhibits the symptoms of uterine and bladder prolapse. Pelvic floor ultrasound allows observing pathological changes in the front, middle and back basins in patients with constipation caused by FPFD, analyzing the changes in structure and function of static and dynamic pelvic floors, and making a more systematic assessment of female pelvic floor lesions, which is conducive to guiding constipation treatment. Therefore, pelvic floor ultrasound has great value in constipation caused by FPFD. In this paper, we review the diagnostic value of pelvic floor ultrasound in constipation due to female pelvic floor dysfunction.

Prospective evaluation of change in levator hiatus dimensions using 3D endovaginal ultrasound before and 1 year after treatment for female pelvic organ prolapse

INTRODUCTION AND HYPOTHESIS

We aimed to determine the change in levator hiatal (LH) dimensions using 3D high-frequency endovaginal ultrasound (EVUS) before and 1 year after treatment for pelvic organ prolapse (POP).

METHODS

Women with prolapse attending the urogynecology clinic between July and October 2009 were recruited. EVUS was performed using multifrequency (9-16 MHz) 360° rotational probe with a built-in 3D automatic acquisition system (Type 2052, ProFocus Ultra view, B-K Medical, Herlev, Denmark). The levator hiatal dimensions that were measured comprised anteroposterior (AP), left-to-right width, and area. Patients were followed up at 1 year, when EVUS was repeated.

RESULTS

Eighty-nine women had symptomatic prolapse. Of these, 43 opted for surgery and 46 for nonsurgical treatment. Levator hiatal dimensions decreased in AP, width, and area at 12 months after surgery compared with baseline (p <0.05). However, there was no change in any of the dimensions after nonsurgical treatment.

CONCLUSION

In contrast to conservative management, there is a significant decrease in levator hiatal dimensions 12 months following surgery for POP.

Dynamic transperineal ultrasound in the workup of men with obstructed defecation: a pilot study

BACKGROUND

Dynamic transperineal ultrasound has been used in women for the noninvasive investigation of functional disorders of the posterior pelvic floor, but its use in men has been limited by technical difficulties related to the consistency of the male perineum.

OBJECTIVES

The aim of this study was to explore the efficacy of dynamic transperineal ultrasound in diagnosing posterior pelvic floor dysfunction in men.

DESIGN

This is a study of diagnostic accuracy.

SETTINGS

This study was performed at a public hospital.

PATIENTS

Forty-six men with symptoms of obstructed defecation were included.

INTERVENTIONS

All patients underwent dynamic transperineal ultrasound 1 week after standard defecography with manometric confirmation when rectoanal dyssynergy was observed.

MAIN OUTCOME MEASURES

Images were obtained, and anorectal angles were measured under resting conditions and during maximal strain. The accuracy of the sonographic method in diagnosing pelvic floor alterations was assessed against defecography (reference method).

RESULTS

: Anorectal angles measured with ultrasound and defecography were not significantly different under resting conditions or maximum strain. Sonographic and reference method findings were concordant in 41 (89.1%) of the cases (25 with rectoanal intussusceptions, 7 with rectorectal intussusceptions, 8 with rectoanal dyssynergy, and 1 with rectorectal intussusception and dyssynergy). In 1 patient with rectoanal intussusception, dynamic transperineal ultrasound was nondiagnostic (low image quality probably due to dehydration of perineal tissues). Discordant dynamic transperineal ultrasound findings included normal findings in another patient with rectoanal intussusception, diagnosis of rectoanal intussusception in 2 men with rectorectal intussusception, and failure to detect dyssynergy in a second patient with rectorectal intussusception and dyssynergy. The sensitivity, specificity, and Cohen κ indices for dynamic transperineal ultrasound were 92.6%, 90.5%, and 82% (rectoanal intussusception); 81.8%, 100%, and 87% (rectorectal intussusception); 90%, 100%, and 93% (rectoanal dyssynergy).

LIMITATIONS

This study was limited by its small size and by the absence of patients with other morphofunctional disorders associated with obstructed defecation.

CONCLUSIONS

Dynamic transperineal ultrasound is potentially useful for diagnosis and follow-up of posterior pelvic floor dysfunction in men.

Ultrasound imaging of the anal sphincter complex: a review

Endoanal ultrasound is now regarded as the gold standard for evaluating anal sphincter pathology in the investigation of anal incontinence. The advent of three-dimensional ultrasound has further improved our understanding of the two-dimensional technique. Endoanal ultrasound requires specialised equipment and its relative invasiveness has prompted clinicians to explore alternative imaging techniques. Transvaginal and transperineal ultrasound have been recently evaluated as alternative imaging modalities. However, the need for technique standardisation, validation and reporting is of paramount importance. We conducted a MEDLINE search (1950 to February 2010) and critically reviewed studies using the three imaging techniques in evaluating anal sphincter integrity.

Quantifying vaginal tissue elasticity under normal and prolapse conditions by tactile imaging

INTRODUCTION AND HYPOTHESIS

Vaginal tactile imaging (VTI) is based on principles similar to those of manual palpation. The objective of this study is to assess the clinical suitability of new approach for imaging and tissue elasticity quantification under normal and prolapse conditions.

METHODS

The study subjects included 31 women with normal and prolapse conditions. The tissue elasticity (Young's modulus) was calculated from spatial gradients in the resulting 3-D tactile images.

RESULTS

Average values for tissue elasticity for the anterior and posterior compartments for normal conditions were 7.4 ± 4.3 kPa and 6.2 ± 3.1 kPa respectively. For Stage III prolapse the average values for tissue elasticity for anterior and posterior compartments were 1.8 ± 0.7 kPa and 1.8 ± 0.5 kPa respectively.

CONCLUSIONS

VTI may serve as a means for 3-D imaging of the vagina and a quantitative assessment of vaginal tissue elasticity, providing important information for furthering our understanding of pelvic organ prolapse and surgical treatment.

Obstetric levator ani muscle injuries: current status

Levator ani muscle (LAM) injuries occur in 13-36% of women who have a vaginal delivery. Although these injuries were first described using magnetic resonance imaging, three-dimensional transperineal and endovaginal ultrasound has emerged as a more readily available and economic alternative to identify LAM morphology. Injury to the LAM is attributed to vaginal delivery resulting in reduced pelvic floor muscle strength, enlargement of the vaginal hiatus and pelvic organ prolapse. There is inconclusive evidence to support an association between LAM injuries and stress urinary incontinence and there seems to be a trend towards the development of fecal incontinence. Longitudinal studies with long-term follow-up assessing the LAM before and after childbirth are lacking. Furthermore, the consequence of LAM injuries on quality of life due to prolapse and/or urinary and fecal incontinence have not been evaluated using validated questionnaires. Direct comparative studies using the above-mentioned imaging modalities are needed to determine the true gold standard for the diagnosis of LAM injuries. This would enable consistency in definition and classification of LAM injuries. Only then could high-risk groups be identified and preventive strategies implemented in obstetric practice.

Three-dimensional anal endosonography in depicting anal-canal anatomy

PURPOSE

This report describes the advantages of 3D anal endosonography in depicting the normal anatomy of the anal canal in relation to sex and age.

MATERIALS AND METHODS

A retrospective study was performed of 85 patients, 33 men and 52 women, previously examined with 3D anal ultrasound (US) for clinically suspected anorectal disease but found to be negative. The examinations were performed with a Bruel and Kjaer US system with a 2050 transducer, scanning from the anorectal junction to the subcutaneous portion of the external anal sphincter (EAS). The 3D reconstructions provided an estimation of sphincter length in the anterior and posterior planes, and axial 2D images enabled calculation of the thickness of the internal anal sphincter (IAS) and EAS in the anterior, posterior and lateral transverse planes.

RESULTS

Distribution of the sphincter complex is asymmetric in both sexes: the EAS and IAS are significantly shorter in females, especially in the anterior longitudinal plane (p=0.005 and p<0.001, respectively). EAS and IAS thickness increases with age, especially the lateral IAS (R(2)=0.37, p<0.001) and the posterior EAS (R(2)=0.29, p=0.01).

CONCLUSIONS

A good knowledge of anal-canal anatomy is essential to detect sphincter abnormalities when assessing pelvic floor dysfunction.

Female pelvic floor dysfunction--an imaging perspective

Female pelvic floor dysfunction encompasses a range of morbidities, including urinary incontinence, female pelvic organ prolapse, anal incontinence and obstructed defecation. Patients often present with symptoms covered by several specialties including gastroenterology, colorectal surgery, urology and gynecology. Imaging can therefore bring clinicians from multiple specialties together by revealing that we frequently deal with different aspects of one underlying problem or pathophysiological process. This article provides an interdisciplinary imaging perspective on the pelvic floor. Modern pelvic floor imaging comprises defecation proctography, translabial and endorectal ultrasound, and static and dynamic MRI. This Perspectives focuses on the potential use of translabial ultrasound, including 3D and 4D applications, for diagnosis of pelvic floor disorders. Over the next decade, pelvic floor imaging will most likely be integrated into mainstream diagnostics in obstetrics and gynecology and colorectal surgery. Using imaging to facilitate communication between different specialties has the potential to greatly improve the multidisciplinary management of complex pelvic floor disorders.

Quantitative assessment of urethral vascularity in nulliparous females using high-frequency endovaginal ultrasonography

PURPOSE

To assess the vascular parameters in the urethra of nulliparous females and to compare the vascularity among various parts of the urethra, using high-frequency endovaginal ultrasonography (EVUS).

METHODS

Twenty-two nulliparous women, mean age 27 years, underwent EVUS using a biplane transducer at 12 MHz frequency. Color Doppler examinations of the urethra were recorded and further evaluated off-line using special software (Pixel Flux) for quantitative assessment of the vascularity. The urethra was divided into four regions of interest (ROIs) in the midsagittal plane and three ROIs in the axial plane. The following parameters were measured: velocity (V), perfused area (A), perfusion intensity (I), pulsatility index (PI), and resistance index (RI). Interobserver and intraobserver reproducibility analysis was also performed.

RESULTS

In midsagittal plane, the midurethra presented the highest value of V and lowest value of A. The intramural part showed the lowest value of I and the highest values of RI and PI. In the distal urethra, the highest value of I and the lowest value of RI was seen. In the axial plane, the values of V, A, and I were statistically significantly higher in the external part of the midurethra compared with the internal part. Excellent interobserver and intraobserver reproducibility was shown in the majority of parameters for the entire urethra.

CONCLUSIONS

Vascularity differs in different parts of the urethra. Pixel Flux is a valuable tool for providing reproducible quantitative analysis of vascular parameters for the entire urethra.

Motion estimation in ultrasound imaging applied to the diagnostic of pelvic floor disorders

The main purpose of this paper is to show the potential of tissue motion estimation in ultrasound imaging for the diagnostic of pelvic floor disorders. We propose to evaluate the tissue motion using a method based on a local deformable model and on image features (local phase and orientation) extracted from the monogenic signal. The proposed method is well adapted to the pelvic organ deformations and estimates motion with subpixel precision without the need for interpolation. The estimated motion is used to visualize the bladder local deformation and to extract quantitative figures such as the deformation parameters and the bladder angle variation. These results could potentially be interesting to characterize the degree of the pelvic organ prolapse.