Anterior and posterior compartment 3D endovaginal ultrasound anatomy based on direct histologic comparison

Use of transrectal high-frequency ultrasound in assessment of middle compartment prolapse

OBJECTIVE

To investigate the superiority of transrectal high-frequency ultrasound (TRUS) in precise assessment of middle compartment prolapse in comparison with routine transperineal ultrasound (TPUS).

METHODS

Prospectively analyzed and compared detection rates of entire cervical length and uterine descent on TPUS and TRUS in 101 patients with pelvic organ prolapse (POP).

RESULTS

Detection rates of entire cervix on TRUS were significantly higher than those on TPUS both at rest and during Valsalva maneuver (90.10% VS 49.50%, 92.08% VS 9.90% respectively, both p < 0.05). Uterine descent was able to be evaluated in 92.08% of patients by TRUS and in 5.94% of patients by TPUS, which was statistically significant (p < 0.05). The interobserver repeatability for the measurements of anterior lip, cervical canal and posterior lip on TRUS was excellent. The mean lengths of anterior lip, cervical canal and posterior lip were significantly increased during Valsalva maneuver than those measured at rest (p < 0.05). And mean length of anterior lip was longer than posterior lip both at rest and during Valsalva (p < 0.05).

CONCLUSION

TRUS can significantly raise detection rates of entire cervix, and make the direct evaluation of uterine descent feasible. TRUS can be used as a complementary method to TPUS to attain more comprehensive and accurate presurgical imaging information in middle compartment prolapse patients.

Levator ani muscle volume and architecture in normal vs. muscle damage patients using 3D endovaginal ultrasound: a pilot study

INTRODUCTION AND HYPOTHESIS

This study aimed to compare the difference in levator ani muscle (LAM) volumes between 'normal' and those with sonographically visualized LAM defects. We hypothesized that the 'muscle damage' group would have a significantly lower muscle volume.

METHODS

The study included patients who had undergone a 3D endovaginal ultrasound. The normal (NM) and damage (DM) muscle groups' architectural changes were evaluated based on anterior-posterior (AP), left-right (LR) diameter, and minimal levator hiatus (MLH) area. The puboanalis-puboperinealis (PA), puborectalis (PR), and pubococcygeus-iliococcygeus (PC) were manually segmented using 2.5 vs. 1.0 mm to find the optimal sequence and to compare the volumes between NM and DM groups. POPQs were compared between the NM and DM groups.

RESULTS

The 1.0-mm segmentation volumes created superior volume analysis. Comparing NM to the DM group showed no significant difference in LAM volume. Respectively, the mean total LAM volumes were 17.27 cm³ (SD = 3.97) and 17.04 cm³ (SD = 4.32), p = 0.79. The mean MLH measurements for both groups respectively were 10.06 cm² (SD = 2.93) and 12.18 cm² (SD = 2.93), indicating a significant difference (p = 0.01). POPQ analysis demonstrated statistically significant differences at Ba and Bp parameters suggesting that the DM group had worse prolapse (p = 0.05, 0.01, respectively).

CONCLUSIONS

While LAM volumes are similar, there is a significant difference in the physical architecture of the LAM and the POPQ parameters in muscle-damaged patients compared to the normal group.

The Correlation Between the Sonographic Course of Transobturator Slings and Sling-Related Pain

OBJECTIVES

To determine whether transobturator slings follow a consistent path and whether there is an association between ultrasonographically visualized sling pattern or position with sling-related pain.

METHODS

This was a cross-sectional retrospective pilot study. We evaluated women who were presented to our clinic for pain or other urogynecologic symptoms following transobturator sling placement between 2009 and 2014. Patients had undergone a 3-dimensional endovaginal pelvic floor ultrasound, assessing minimal levator hiatus, antero-posterior diameter, left-right diameter, and the hiatal shape. The mesh patterns were categorized as seagull patterns (normal), lopsided, flat, and convoluted.

RESULTS

A total of 68 cases were reviewed. Fifty patients reported pain, and 18 did not. There were wide variations in the course of the slings. The sling center- minimal levator hiatus position ranged 14.8 mm below and 17.9 mm above the minimal levator hiatus. The lateral arm insertion points ranged between 17.1 mm below and 16.6 mm above the minimal levator hiatus. The right arm insertion points ranged between 9.6 mm below and 18.8 mm above the minimal levator hiatus. Thirty-five of 68 (70%) patients with pain and 13 of 18 (72.2%) without had abnormal sling patterns. The abnormal sling shape was not correlated with pain (P = 1). The levator shape trended toward a statistical significant correlation with sling shape abnormality (P = .084).

CONCLUSIONS

This population of women with transobturator sling complications demonstrated wide variations in anatomic paths. Neither the abnormal sling shape nor the distance of the center of the tape from the minimal levator hiatus level were correlated with pain.

Imaging modalities for the detection of posterior pelvic floor disorders in women with obstructed defaecation syndrome

BACKGROUND

Obstructed defaecation syndrome (ODS) is difficulty in evacuating stools, requiring straining efforts at defaecation, having the sensation of incomplete evacuation, or the need to manually assist defaecation. This is due to a physical blockage of the faecal stream during defaecation attempts, caused by rectocele, enterocele, intussusception, anismus or pelvic floor descent. Evacuation proctography (EP) is the most common imaging technique for diagnosis of posterior pelvic floor disorders. It has been regarded as the reference standard because of extensive experience, although it has been proven not to have perfect accuracy. Moreover, EP is invasive, embarrassing and uses ionising radiation. Alternative imaging techniques addressing these issues have been developed and assessed for their accuracy. Because of varying results, leading to a lack of consensus, a systematic review and meta-analysis of the literature are required.

OBJECTIVES

To determine the diagnostic test accuracy of EP, dynamic magnetic resonance imaging (MRI) and pelvic floor ultrasound for the detection of posterior pelvic floor disorders in women with ODS, using latent class analysis in the absence of a reference standard, and to assess whether MRI or ultrasound could replace EP. The secondary objective was to investigate differences in diagnostic test accuracy in relation to the use of rectal contrast, evacuation phase, patient position and cut-off values, which could influence test outcome.

SEARCH METHODS

We ran an electronic search on 18 December 2019 in the Cochrane Library, MEDLINE, Embase, SCI, CINAHL and CPCI. Reference list, Google scholar. We also searched WHO ICTRP and clinicaltrials.gov for eligible articles. Two review authors conducted title and abstract screening and full-text assessment, resolving disagreements with a third review author.

SELECTION CRITERIA

Diagnostic test accuracy and cohort studies were eligible for inclusion if they evaluated the test accuracy of EP, and MRI or pelvic floor ultrasound, or both, for the detection of posterior pelvic floor disorders in women with ODS. We excluded case-control studies. If studies partially met the inclusion criteria, we contacted the authors for additional information.

DATA COLLECTION AND ANALYSIS

Two review authors performed data extraction, including study characteristics, 'Risk-of-bias' assessment, sources of heterogeneity and test accuracy results. We excluded studies if test accuracy data could not be retrieved despite all efforts. We performed meta-analysis using Bayesian hierarchical latent class analysis. For the index test to qualify as a replacement test for EP, both sensitivity and specificity should be similar or higher than the historic reference standard (EP), and for a triage test either specificity or sensitivity should be similar or higher. We conducted heterogeneity analysis assessing the effect of different test conditions on test accuracy. We ran sensitivity analyses by excluding studies with high risk of bias, with concerns about applicability, or those published before 2010. We assessed the overall quality of evidence (QoE) according to GRADE.

MAIN RESULTS

Thirty-nine studies covering 2483 participants were included into the meta-analyses. We produced pooled estimates of sensitivity and specificity for all index tests for each target condition. Findings of the sensitivity analyses were consistent with the main analysis. Sensitivity of EP for diagnosis of rectocele was 98% (credible interval (CrI)94%-99%), enterocele 91%(CrI 83%-97%), intussusception 89%(CrI 79%-96%) and pelvic floor descent 98%(CrI 93%-100%); specificity for enterocele was 96%(CrI 93%-99%), intussusception 92%(CrI 86%-97%) and anismus 97%(CrI 94%-99%), all with high QoE. Moderate to low QoE showed a sensitivity for anismus of 80%(CrI 63%-94%), and specificity for rectocele of 78%(CrI 63%-90%) and pelvic floor descent 83%(CrI 59%-96%). Specificity of MRI for diagnosis of rectocele was 90% (CrI 79%-97%), enterocele 99% (CrI 96%-100%) and intussusception 97% (CrI 88%-100%), meeting the criteria for a triage test with high QoE. MRI did not meet the criteria to replace EP. Heterogeneity analysis showed that sensitivity of MRI performed with evacuation phase was higher than without for rectocele (94%, CrI 87%-98%) versus 65%, CrI 52% to 89%, and enterocele (87%, CrI 74%-95% versus 62%, CrI 51%-88%), and sensitivity of MRI without evacuation phase was significantly lower than EP. Specificity of transperineal ultrasound (TPUS) for diagnosis of rectocele was 89% (CrI 81%-96%), enterocele 98% (CrI 95%-100%) and intussusception 96% (CrI 91%-99%); sensitivity for anismus was 92% (CrI 72%-98%), meeting the criteria for a triage test with high QoE. TPUS did not meet the criteria to replace EP. Heterogeneity analysis showed that sensitivity of TPUS performed with rectal contrast was not significantly higher than without for rectocele(92%, CrI 69%-99% versus 81%, CrI 58%-95%), enterocele (90%, CrI 71%-99% versus 67%, CrI 51%-90%) and intussusception (90%, CrI 69%-98% versus 61%, CrI 51%-86%), and was lower than EP. Specificity of endovaginal ultrasound (EVUS) for diagnosis of rectocele was 76% (CrI 54%-93%), enterocele 97% (CrI 80%-99%) and intussusception 93% (CrI 72%-99%); sensitivity for anismus was 84% (CrI 59%-96%), meeting the criteria for a triage test with very low to moderate QoE. EVUS did not meet the criteria to replace EP. Specificity of dynamic anal endosonography (DAE) for diagnosis of rectocele was 88% (CrI 62%-99%), enterocele 97% (CrI 75%-100%) and intussusception 93% (CrI 65%-99%), meeting the criteria for a triage test with very low to moderate QoE. DAE did not meet the criteria to replace EP. Echodefaecography (EDF) had a sensitivity of 89% (CrI 65%-98%) and specificity of 92% (CrI 72%-99%) for intussusception, meeting the criteria to replace EP but with very low QoE. Specificity of EDF for diagnosis of rectocele was 89% (CrI 60%-99%) and for enterocele 97% (CrI 87%-100%); sensitivity for anismus was 87% (CrI 72%-96%), meeting the criteria for a triage test with low to very low QoE.

AUTHORS' CONCLUSIONS

In a population of women with symptoms of ODS, none of the imaging techniques met the criteria to replace EP. MRI and TPUS met the criteria of a triage test, as a positive test confirms diagnosis of rectocele, enterocele and intussusception, and a negative test rules out diagnosis of anismus. An evacuation phase increased sensitivity of MRI. Rectal contrast did not increase sensitivity of TPUS. QoE of EVUS, DAE and EDF was too low to draw conclusions. More well-designed studies are required to define their role in the diagnostic pathway of ODS.

Recommended standardized anatomic terminology of the posterior female pelvis and vulva based on a structured medical literature review

BACKGROUND

Anatomic terminology in both written and verbal forms has been shown to be inaccurate and imprecise.

OBJECTIVE

Here, we aimed to (1) review published anatomic terminology as it relates to the posterior female pelvis, posterior vagina, and vulva; (2) compare these terms to "Terminologia Anatomica," the internationally standardized terminology; and (3) compile standardized anatomic terms for improved communication and understanding.

STUDY DESIGN

From inception of the study to April 6, 2018, MEDLINE database was used to search for 40 terms relevant to the posterior female pelvis and vulvar anatomy. Furthermore, 11 investigators reviewed identified abstracts and selected those reporting on posterior female pelvic and vulvar anatomy for full-text review. In addition, 11 textbook chapters were included in the study. Definitions of all pertinent anatomic terms were extracted for review.

RESULTS

Overall, 486 anatomic terms were identified describing the vulva and posterior female pelvic anatomy, including the posterior vagina. "Terminologia Anatomica" has previously accepted 186 of these terms. Based on this literature review, we proposed the adoption of 11 new standardized anatomic terms, including 6 regional terms (anal sphincter complex, anorectum, genital-crural fold, interlabial sulcus, posterior vaginal compartment, and sacrospinous-coccygeus complex), 4 structural terms (greater vestibular duct, anal cushions, nerve to the levator ani, and labial fat pad), and 1 anatomic space (deep postanal space). In addition, the currently accepted term rectovaginal fascia or septum was identified as controversial and requires further research and definition before continued acceptance or rejection in medical communication.

CONCLUSION

This study highlighted the variability in the anatomic nomenclature used in describing the posterior female pelvis and vulva. Therefore, we recommended the use of standardized terminology to improve communication and education across medical and anatomic disciplines.

Durability of Macroplastique volume and configuration in women with stress urinary incontinence secondary to intrinsic sphincter deficiency: A retrospective review

OBJECTIVES

To evaluate the durability of Macroplastique® (MPQ) volume and configuration in women with stress urinary incontinence (SUI) secondary to intrinsic sphincter deficiency (ISD) using serial three-dimensional ultrasound (3DUS) measurements.

METHODS

Following Institutional Review Board approval, charts of women with SUI and ISD (defined based on leak point pressure; lateral imaging of urethral support without hypermobility) who underwent MPQ were reviewed from a prospectively maintained database. All had at least two serial transperineal 3DUS measurements with no MPQ or other bulking agent injection between measurements. 3DUS was performed using the Philips IU22 ultrasound system with endovaginal 3D 9-3V end-fire probe typically at 6-8 weeks post-injection and yearly thereafter. The same imaging team blinded to clinical outcomes evaluated volume and configuration (circumferential/symmetric or asymmetric) at each 3DUS.

RESULTS

Between 2011 and 2019, 62 of 174 women met study criteria. Those with prior other bulking agent injection or having ≤1 3DUS follow-up were excluded. Seventy-one percent of patients had one injection, while the remainder had two or more (29%). Median time between first and second 3DUS was 12 months. The mean change in MPQ volume between the first and last 3DUS measurement was -0.2 cc (95% CI: -0.5 to 0.004; P = .054). A median of 5.0 cc were injected in each patient. Forty-seven women had symmetric MPQ at first 3DUS, of whom only five (11%) had a follow-up 3DUS showing asymmetric MPQ distribution.

CONCLUSIONS

At mid-term follow-up, repeat transperineal 3DUS after MPQ injection revealed minimal change in volume and configuration in the urethral wall.

Association between 3D endovaginal and 2D perineal pelvic floor ultrasound findings and symptoms in women presenting with mid-urethral sling complications

OBJECTIVES

To present the characteristics of women attending a tertiary urogynecology pelvic floor scan clinic with mid-urethral sling (MUS) complications and examine the association between patient symptoms and findings on two-dimensional (2D) perineal and three-dimensional (3D) endovaginal ultrasound.

METHODS

This was a cross-sectional study of all women with MUS complications referred to a specialist pelvic floor ultrasound clinic between October 2016 and October 2018. Detailed history was obtained regarding their symptoms and time of onset. All patients underwent 2D perineal and 3D endovaginal ultrasound assessment. The association between patient symptoms and ultrasound findings was evaluated using logistic regression analysis. Only symptomatic women with a single MUS, without other pelvic floor mesh, prior mesh excision or bulking agents, were included in the regression analysis.

RESULTS

A total of 311 women with a history of MUS surgery were seen during the study period. Vaginal and/or non-vaginal pain was reported by 80% of patients and this was the primary presenting complaint in 59% of the patients. One-third of the patients reported symptoms starting within 4 weeks after surgery. The data of 172 patients were included in the regression analysis. MUS position within the rhabdosphincter was significantly associated with voiding dysfunction (odds ratio (OR), 10.6 (95% CI, 2.2-50.9); P = 0.003). Voiding dysfunction was highest in those with C-shaped MUS both at rest and on Valsalva maneuver (OR, 3.2 (95% CI, 1.3-7.6); P < 0.001). MUS position in the distal third of the urethra was significantly associated with a higher rate of recurrent urinary tract infection (OR, 2.9 (95% CI, 1.3-6.3); P = 0.01).

CONCLUSIONS

Pelvic floor ultrasound can provide insight into the position and shape of the MUS, which could explain some patient symptoms and guide management or surgical planning. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Are there age-related changes in the measurements of the urethral sphincter complex in nulliparous women? A three-dimensional ultrasound assessment

INTRODUCTION AND HYPOTHESIS

The objective was to determine age-related changes in measurements of urethral sphincter complex components in asymptomatic nulliparous women.

METHODS

Eighty nulliparous women ≥18 years underwent 3D ultrasound of the anterior pelvic compartment in a cross-sectional study. Measurements of the urethral sphincter components (smooth muscle sphincter [SMS] and striated urinary sphincter [SUS]) and urethra including area, length, width, and distance of the SUS and SMS from the urethrovesical junction were obtained. The women were grouped into four age groups: < 30 years (group A), 30 to < 45 (group B), 45 to < 60 (group C), and ≥ 60 years (group D). Age-related differences in the measurements were determined. Inter-rater and intra-rater agreement were performed for 20 nulliparous women.

RESULTS

There were 24, 18, 26, and 12 women in groups A, B, C, and D respectively. None of the urethral sphincter complex measurements was significantly associated with age (p > 0.05). No differences were found between the groups for any measurements using one-way ANOVA and multiple comparison pairwise comparison (p > 0.05) other than width of SMS (C > A), urethral length (C > A), and distance of SUS from urethrovesical junction (C > D). Inter-rater and intra-rater agreement were moderate for area, length, and width of SUS (intraclass correlation 0.6) and good (intraclass correlation above 0.8) for the remaining measurements.

CONCLUSION

Other than width of SMS, urethral length, and distance of SUS from urethrovesical junction, the dimensions of urethral sphincter complex components, as visualized by 3D endovaginal ultrasound, do not vary with age.

Study on the Effects of Potential Affecting Factors on the Midurethral Volume by High-Frequency 3-Dimensional Transvaginal Ultrasound

OBJECTIVES

The anatomic integrity of the female mid urethra is an important factor for urinary continence. However, the associations between the urethral volume and potential affecting factors still remain uncertain. The aim of this study was to investigate the impact of potential factors, including age, height, weight, body mass index (BMI), parity number, delivery mode, and menopause, on the midurethral volume to assist in more-accurate evaluations of urethral anatomy and urinary continence mechanisms in clinical practice.

METHODS

A total of 244 women were included in this study. All patients had no incontinence symptoms and underwent transvaginal ultrasound examinations. Detailed histories and demographic data were collected. Urethral volumes were acquired, and volume parameters were measured offline, including the urethral sphincter volume (USV), midurethral complex volume (CV), and inner core volume (ICV). Correlations were analyzed by the Spearman test. For categorical variables, an analysis of variance, Mann-Whitney tests, or Kruskal-Wallis tests were used to estimate associations of potential affecting factors and volumes.

RESULTS

The mean age, height, weight, and BMI ± SD of the patients were 35.42 ± 9.88 years, 161.50 ± 4.96 cm, 60.72 ± 11.42 kg, and 23.29 ± 4.20 kg/m² , respectively. Among potential affecting factors, age had a weak correlation with the USV, CV, and ICV (P = .031, .003, and .004; r = 0.140, 0.193, and 0.187), whereas parity numbers significantly affected the USV, CV, and ICV (P = .014, .021, and .026). The urethral volume became larger with increasing parity. Height (P = .391, .637, and .647), weight (P = .077, .130, and .245), BMI (P = .583, .592, and .643), delivery mode (P = .483, .171, and .104), and menopausal status (P = .611, .717, and .830) had no significant impact on the midurethral volume data (USV, CV, and ICV).

CONCLUSIONS

The midurethral volume tended to increase with age and parity in continent women.

Gynecological influencing factors on the rectovaginal septum's morphology

INTRODUCTION AND HYPOTHESIS

The objective was to determine the mean morphometric characteristics of the rectovaginal septum (RVS) and its variations in correlation with the number of pregnancies, method of delivery, parity, and estrogenic exposure.

METHODS

An observational, cross-sectional, retrospective, descriptive, and comparative study was carried out. Pelvic MRI of Hispanic women (≥15 years of age) from the northeast of Mexico were obtained. Age and obstetric and gynecological history were registered and the sample women were categorized by their variables. Length and thickness measurements were standardized.

RESULTS

A total of 102 MRI studies were included, with a mean age of 41; 24.5% were nulligravida, the rest primi- or multigravida. Vaginal delivery was the most common type (49.35%), 16.88% had a cesarean section, and 31.17% had mixed delivery. 74.5% of the women were premenopausal. The mean RVS length was 73.2 ± 15.3 mm, with a thickness of 2.8 ± 1.7, 2.2 ± 1.2, and 2.5 ± 1.3 mm for the upper, middle, and lower thirds respectively. There were tendencies to increase the length of the RVS, and the thickness of the upper and middle thirds in the non-pregnancy and the at-least-one-pregnancy groups; to increase the length and middle-third thickness in those with mixed delivery, and increased upper- and lower-third thickness in those with only a cesarean section. Multiparous women with vaginal delivery had significantly longer and thicker RVS than primiparous. Premenopausal women had significantly longer RVS with a tendency to lose thickness toward postmenopause.

CONCLUSIONS

The morphology of RVS can be modified by different factors such as age, number of pregnancies, number of births, and estrogenic exposure. This structure should be evaluated and taken into account in preoperative management and surgical technique planning.

Macroplastique for women with stress urinary incontinence secondary to intrinsic sphincter deficiency

Objective

To evaluate the subjective and objective outcomes of Macroplastique® (MPQ) in women with stress urinary incontinence (SUI) secondary to intrinsic sphincter deficiency (ISD).

Materials and Methods

Following Institutional Review Board (IRB) approval, charts of non-neurogenic women with SUI secondary to ISD who underwent MPQ injection and had 6 months minimum follow-up were reviewed from a prospectively maintained database. Patients were divided into 3 groups: Naïve (Group I), Prior Anti-Incontinence Surgery (Group II), and combined Prior Bulking Agent and Anti-Incontinence Surgery (Group III). Data collected included SUI self-report, Urogenital Distress Inventory (UDI-6) Question 3, and VAS Quality of Life (QoL) Questionnaire scores at baseline and in follow-up. Three-dimensional ultrasound (3DUS) evaluated volume/configuration of MPQ. Success was defined after the last MPQ injection as a UDI-6 Question 3 score of 0 (dry) or 1, and no reoperation for SUI.

Results

From 2011-2017, 106 of 142 women met study criteria. At a median follow-up of 20 months (mean=26 months; range: 6-71), success rate was 41% for Group I, 40% for Group II, and 65% for Group III (p = 0.22). QoL scores were significantly improved over baseline in all groups. There was no significant difference in clinical outcome between the asymmetrical and symmetrical group on 3DUS. The completely dry rate was highest in Group III at 29%, compared to 4% for Group I and 15% for Group II (p = 0.05).

Conclusion

Macroplastique® improved subjective and objective outcome measures for SUI secondary to ISD as both a primary and secondary treatment option in women.

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.

Repeatability of Female Midurethral Measurement Using High-Frequency 3-Dimensional Transvaginal Ultrasonography

OBJECTIVES

Imaging assessment of the female urethra is critical for diagnosis and treatment of urinary incontinence. High-frequency 3-dimensional (3D) transvaginal ultrasonography (TVUS) is a novel technique for evaluating the female urethra. The aim of this study was to test the repeatability of 3D TVUS between examiners without prior experience with TVUS.

METHODS

Fifty women underwent 3D TVUS. Two examiners without prior experience analyzed the urethral volumes and measured the urethral parameters. Two-dimensional (2D) parameters included urethral sphincter length and urethral sphincter thickness; 3D parameters included urethral sphincter volume, midurethral complex volume, and inner core volume. One of the examiners repeated the evaluations 1 month later. Subsequently, the measurements were compared.

RESULTS

The mean age of the patients ± SD was 34.1 ± 8.1 (range, 23-55) years; the mean height, weight, and body mass index were 160.44 ± 5.12 (range, 150-173) cm, 61.80 ± 13.64 (range, 45-110) kg, and 23.98 ± 4.91 (range, 17.53-39.92) kg/m² , respectively. The results of our study showed excellent to good intraobserver repeatability (intraclass correlation coefficient [ICC], 0.75-0.87) for the evaluations of all parameters but urethral sphincter length (moderate ICC, 0.53), whereas they showed good to moderate interobserver repeatability (ICC, 0.44-0.77) for all parameters. The repeatability of 3D volumes (ICC, 0.59-0.87) tended to be better than that of 2D parameters (ICC, 0.44-0.76).

CONCLUSIONS

The intraobserver and interobserver repeatability of high-frequency 3D TVUS measurements of the female urethra was excellent to moderate between examiners without previous experience. The repeatability of 3D measurements tended to be better than that of 2D parameters.

Demographic features of female urethra length

AIMS

To determine cohort urethral length, identify epidemiological factors influencing the parameter and to establish the percentage of cases with clinically relevant outsized urethras.

METHODS

Prospective cohort study conducted in two tertiary clinical centers between 2013 and 2017. Nine hundred and twenty seven consecutive adult, Caucasian females attending outpatients' clinics were included. The urethral length has been measured in pelvic floor ultrasound examination. The exclusion criteria were inadequate bladder filling (<200 mL; >400 mL), previous history of pelvic floor surgery, and no consent.

RESULTS

Urethral length varied from 19 to 45 mm. The distribution of the examined parameter was normal. Obese patients had significantly longer urethras as compared to non-obese subjects. Number of vaginal deliveries was connected with shorter urethral length. The limitations of the study are: analysis only of Caucasian patients and subjects without previous pelvic floor surgeries.

CONCLUSIONS

Differences in urethral length in the female population were demonstrated. Thirty percent of patients have atypical urethras that may be a risk factor for sling surgery failure. We therefore postulate introduction of urethral measurement before the procedure.

Ultrasound Imaging of the Pelvic Floor

This article discusses the background and appraisal of endoluminal ultrasound of the pelvic floor. It provides a detailed anatomic assessment of the muscles and surrounding organs of the pelvic floor. Different anatomic variability and pathology, such as prolapse, fecal incontinence, urinary incontinence, vaginal wall cysts, synthetic implanted material, and pelvic pain, are easily assessed with endoluminal vaginal ultrasound. With pelvic organ prolapse in particular, not only is the prolapse itself seen but the underlying cause related to the anatomic and functional abnormalities of the pelvic floor muscle structures are also visualized.

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.

Is a new high-resolution probe better than the standard probe for 3D anal sphincter and levator ani imaging?

The aim of our study was to determine the accuracy of a new three-dimensional (3D) endoluminal ultrasound probe in assessing the levator ani muscle and anal sphincter complex. A total of 85 patients who had undergone concurrent 3D endovaginal (EVUS) and 3D endoanal (EAUS) ultrasound with both the standard BK 2052 probe and the new high-definition BK 8838 probes were included. For EVUS volumes, the levator ani deficiency (LAD) scores were calculated for each probe. For the EAUS volumes, any defects in the external anal sphincter (EAS) and the internal anal sphincter (IAS) visualized with each probe were recorded. The 3D volumes were evaluated in a blinded fashion. Appropriate statistics were utilized to assess absolute agreements between each pair of imaging modalities. The mean age of the patient population was 59 years (SD ± 10.76), the mean body mass index (BMI) was 28.36 (SD ± 5.99), and the median parity was 2 (range 1, 7). In all, 93% of the patients were Caucasian, 31% had stage 0 or 1 prolapse, while 59% had stage 2 prolapse. The mean total LAD score obtained on EVUS with the standard and the new probes were 11.49 (SD ± 4.94) and 11.53 (SD ± 5.01), respectively, p = 0.3778. Among the 53 patients who had EAUS with both probes, exact agreement for visualization of EAS and IAS for the standard and the new probes was 83% and 98%, respectively. Both transducers can be used for endovaginal imaging of the levator ani muscles interchangeably. Both transducers can be used for endoanal imaging of anal sphincter complex interchangeably.

Peroxide-enhanced 3-dimensional endovaginal ultrasound imaging for diagnosis of rectovaginal fistula

We present a case of a rectovaginal fistula identified with peroxide-enhanced 3-dimensional endovaginal ultrasonography.

CASE

A 36-year-old woman with history of ulcerative colitis, status post-ileoanal J-pouch anastomosis, and total proctocolectomy presented with leakage of stool from her vagina. The fistula tract could not be fully visualized directly or identified on endoanal ultrasonography, but was diagnosed by peroxide-enhanced endovaginal ultrasound.The use of peroxide-enhancement while performing 3-dimensional endovaginal sonographic imaging may be of benefit to patients with rectovaginal fistulas that cannot be fully evaluated by physical examination or more typical use of endoanal ultrasonography.

Is there a correlation between levator ani and urethral sphincter complex status on 3D ultrasonography?

INTRODUCTION AND HYPOTHESIS

To determine the correlation between levator ani deficiency (LAD) and urethral sphincter complex measurements as visualized on 3D endovaginal ultrasonography, and to compare the LAD score with continence status.

METHODS

This was a retrospective analysis of patients seen at our institution between January 2011 and August 2013. Patients were dichotomized into those with urodynamic stress urinary incontinence (SUI) and those with no SUI. Levator ani status was evaluated using a validated scoring system yielding scores of 0 - 6 (normal levator ani/mild LAD), 7 - 12 (moderate LAD), and 13 - 18 (severe LAD). The length, horizontal diameter, and cross-sectional area of the urethra, and the length, width, and the area of the rhabdomyosphincter and smooth muscle sphincter were likewise measured using 3D ultrasound volumes.

RESULTS

Of the 80 patients included, 54 (67.5%) had SUI and 26 (32.5%) were continent. 18 (22.5%) had evidence of mild LAD, 54 (67.5%) had moderate LAD, and 8 (10.0%) had severe LAD. Among patients with SUI, those with normal levator ani muscles or mild LAD had greater urethral smooth muscle width than those with moderate and severe LAD (p = 0.0238). A greater proportion of patients with SUI also had moderate to severe LAD than continent patients (p = 0.0177, OR 3.59, 95% CI 1.21 - 10.65). There was no difference in LAD distribution by type of stress incontinence (presence or absence of intrinsic sphincter deficiency; p =  .2377).

CONCLUSIONS

LAD and urethral sphincter complex status, as visualized on 3D ultrasonography, are independent factors. Moderate to severe LAD is more prevalent in patients with SUI.

The rectovaginal septum: visible on magnetic resonance images of women with Mayer-Rokitansky-Küster-Hauser syndrome (Müllerian agenesis)

INTRODUCTION AND HYPOTHESIS

Ongoing debate exists about whether the rectovaginal septum (Denonvilliers' fascia) is myth or reality. This study evaluates magnetic resonance images (MRI) of women with Müllerian agenesis for the presence of fascial layers between the rectum and the bladder to test the hypothesis that this layer exists in the absence of the vagina.

METHODS

This is a secondary analysis of a study describing MRI aspects in women with vaginal agenesis before and after laparoscopic Vecchietti procedure. Study participants (n =16) had a multiplanar pelvic MR scan. Images were evaluated independently by two investigators (MH, JOLD) for the appearance of layers separate from the bladder and rectum in the area of interest, with characteristic anatomical features of the septum.

RESULTS

Participants' mean age was 19.4±2.6 years ± standard deviation (SD). In 12 of 16 patients (75 %) a distinct layer between rectum and bladder was identified in either the axial(4/16; 25 %) or sagittal (12/16; 75 %) scan or both. Characteristic anatomical features included lateral attachment to the levator ani muscle, cranial fusion to the cul-de-sac peritoneum,and caudal insertion into the perineal body.Conclusions Three quarters of women with Müllerian agenesis have a visible layer between bladder and rectum. As none of the participants had a vagina, these results support the existence of a rectovaginal septum, separate from a vaginal adventitia.

Three-dimensional endovaginal sonography of synthetic implanted materials in the female pelvic floor

The objective of this pictorial essay is to emphasize the ability of 3-dimensional endovaginal sonography to image synthetic implanted materials in the female pelvic floor. Implanted materials discussed in this pictorial essay include polypropylene vaginal mesh, polypropylene suburethral slings, and urethral bulking agents. Three-dimensional endovaginal sonography allows for more detailed imaging compared to computed tomography and magnetic resonance imaging of the female pelvic floor, in that each plane can be manipulated to show unique images of synthetic implanted materials.

Transvaginal sling release with intraoperative ultrasound guidance

INTRODUCTION

Visualization of a midurethral sling may be challenging intraoperatively, especially if the sling is deep, well healed, not in the usual location, or made of materials that are not colored.

CASE

We present the case of a 71-year-old woman presenting with a history of incomplete bladder emptying and debilitating voiding dysfunction documented by uroflowmetry and postvoid residual after a tension-free vaginal tape placement. Medications in addition to attempts to dilate her urethra failed to provide her with adequate relief. Intraoperative 3-dimensional ultrasound guidance was used to transect the sling that was otherwise unable to be localized with examination alone.

CONCLUSIONS

Surgical transection of a tension-free vaginal tape can be safely performed under the guidance of ultrasound. At her 12-month follow-up visit, the patient did not have urinary incontinence or voiding dysfunction.