Translabial US and Dynamic MR Imaging of the Pelvic Floor: Normal Anatomy and Dysfunction

Advancements in Magnetic Resonance Imaging for the Evaluation of Pelvic Organ Prolapse: A Comprehensive Review

Pelvic organ prolapse (POP) is a major health issue for women, making accurate diagnosis and assessment essential for effective clinical management. Among the various imaging techniques used for POP evaluation, translabial ultrasound and fluoroscopy have been widely utilized. Translabial ultrasound is a non-invasive, cost-effective method that provides real-time dynamic imaging of the pelvic floor during activities such as straining. Fluoroscopy, often employed in defecography, offers real-time visualization of pelvic organ movement but is limited by radiation exposure. Magnetic resonance imaging (MRI), with its superior soft tissue contrast and non-invasive nature, has emerged as a valuable tool for providing detailed anatomical and functional insights into POP This review outlines the advancements in using MRI to assess POP. It highlights the technical advantages, clinical applications, comparisons with other imaging methods, and future research directions. By analyzing recent research, we aim to clarify the role of MRI in evaluating POP and encourage its integration into clinical practice.

Diagnostic utility of translabial ultrasound in pelvic organ prolapse: a prospective observational study

BACKGROUND

The increasing awareness of women's health issues, specifically pelvic organ prolapse (POP) and urinary incontinence (UI), has spurred a surge in patients seeking specialised advice for these conditions, necessitating modern diagnostic approaches for such issues. This study explored the diagnostic utility of translabial ultrasound for POP, emphasising its correlation with clinical assessments based on International Continence Society (ICS) criteria.

METHODS

Seventy-one patients with POP Quantification System (POP-Q) stage 0-IV with or without UI were prospectively enrolled at Jagiellonian University Medical College between 2014 and 2016. The study objectives included evaluating diagnostic accuracy and concordance across pelvic compartments, correlating the diagnoses with patient-reported symptoms, and identifying variables contributing to diagnostic discrepancies.

RESULTS

Translabial ultrasound identified POP in 74.5% of the patients, aligning closely with clinical evaluations. Concordance was the highest in assessments performed in the medial compartment (85.8%), while assessments performed in the anterior (29.6%) and posterior (29.6%) compartments showed higher rates of discrepancies. Correlation analyses showed varying associations, with the posterior compartment exhibiting the least pronounced correlation (R = 0.72, p < 0.0001). Self-perceive POP showed no discernible differences in relation to ultrasonographic and clinical assessments. Among the respondents, 55.9% reported experiencing the sensation of POP. Mean POP levels determined using the two approaches precisely matched in 46.5% of these cases. Discrepancies involved variables such as self-perceived POP, number of deliveries, child weight at birth, UI, and sexual activity.

CONCLUSIONS

Translabial ultrasound showed robust correlation with clinical assessments for evaluating POP, especially for defining defects and facilitating treatment-related decision-making. Our findings highlight the reliability of this method, particularly for assessments in the medial compartment. The evidence did not indicate the superiority of either method in detecting POP disorders for symptomatic versus asymptomatic patients. Significantly, a higher POP-Q measurement in clinical examination was correlated with greater sexual activity.

Value of transperineal three-dimensional ultrasonography in diagnosis of pelvic floor dysfunction

OBJECTIVES

To investigate the correlation between 3-dimensional ultrasonography parameters and pelvic floor dysfunction (PFD) and its application value in diagnosis and treatment.

METHODS

Ninety-two patients with PFD and 22 without who underwent 3-dimensional ultrasonography were selected. Transperineal 3-dimensional ultrasonography was performed by Voluson E8 colour Doppler ultrasonography to analyse the anteroposterior diameter (LHAD), transverse diameter (LHLD), pelvic diaphragmatic hiatus area (LHA), and bladder neck mobility (BND) of the patients. Diagnostic sensitivity and specificity of ultrasound parameters in PFD were analysed using Receiver Operating Characteristic (ROC) curves. Paired sample t test was used to analyse the improvement of pelvic floor muscle training (PFMT) in patients with PFD.

RESULTS

Patients with PFD had significantly higher levels of △LHAD, △LHLD, △LHA, and BND than controls (all P < .01). Binary logistic regression analysis showed that △LHA or BND levels were independent risk factors for the development of PFD. The ROC results showed that the area under the ROC curve with BND level was the highest (0.917). The diagnostic sensitivity of BND in PFD was 100.0% and the specificity was 70.7%. In urinary incontinence (UI) patients, there was a significant positive correlation between the occurrence of UI and BND levels (all r > 0, P < .05). After PFMT treatment, the levels of △LHAD, △LHLD, △LHA, and BND in patients with PFD were significantly decreased (all P < .001).

CONCLUSIONS

The abnormal changes in the level of 3-dimensional ultrasound parameters can be used as a sensitive indicator to evaluate PFD and a guiding parameter for PFMT treatment.

ADVANCES IN KNOWLEDGE

The feasibility of operation and repetition by 3-dimensional pelvic floor ultrasonography could provide a reliable imaging basis for clinical diagnosis and treatment of patients with PFD.

Pelvic floor imaging in women with hemorrhoidal disease: An anatomical feasibility study

OBJECTIVE

To compare pelvic floor muscle and organ structures in women with and without hemorrhoidal disease (HD) using magnetic resonance imaging (MRI).

MATERIAL AND METHODS

Pelvic MRI measurements and computer-based medical records of women diagnosed with HD between January 2018 and March 2021 were analyzed. Parameters including pubococcygeal distance, puborectal distance, posterior anorectal angle, obturator internus muscle area, presence of levator ani muscle defect, genital hiatus length, vaginal length, uterocervical angle, cervix-upper vagina angle, and cervix-middle vagina angle were evaluated. The control group consisted of women without HD, matched for age and body mass index.

RESULTS

Puborectal hiatus distance was higher in the HD group (59.2 ​± ​8.7 ​mm vs. 55.5 ​± ​7.1 ​mm, p ​= ​0.03). Similarly, the distance to the M line was greater in the HD group (18.3 ​± ​4.8 ​mm vs. 16 ​± ​4.6 ​mm, p ​= ​0.04). Obturator internus muscle area was found to be lower in the HD group compared to the non-HD group (1721 ​± ​291.4 ​mm2 vs. 1897.5 ​± ​352.5 ​mm2, p ​= ​0.02). Additionally, the presence of unilateral levator ani muscle defect was higher in HD patients (p ​= ​0.03). There was a negative correlation between birthweight and obturator internus muscle area (r ​= ​-0.388, p ​= ​0.02), and a positive correlation with M line distance (r ​= ​0.344, p ​= ​0.04).

CONCLUSION

Levator ani muscle defects and obturator internus muscle area, indicators of pelvic floor dysfunction, are more common in patients with hemorrhoidal disease.

Clinical value of MR defecography: What additional knowledge is provided by the radiologist to the surgeon?

PURPOSE

To evaluate the clinical value of MR defecography in supporting surgical decision-making and management strategies in a consecutive series of patients.

MATERIAL AND METHODS

A consecutive series of patients with clinical suspicion of pelvic disorders who underwent MR defecography at a single university hospital from January 2021 to June 2024 were included. MR defecography was performed at rest (axial/sagittal and coronal T2-weighted sequences), during squeezing, straining, and evacuation (dynamic sagittal T2-weighted sequences). An expert surgeon assessed his satisfaction about the diagnostic information given by the prospective radiological report as: 1: insufficient, 2: sufficient, 3: good, 4: excellent. For patients who underwent surgery, the same surgeon assessed the usefulness of the MR defecography, using a score from 1 to 4 (1: discordant findings, useless exam; 2: concordant findings without new information; 3: concordant findings, useful new information; 4: concordant findings, extremely useful new information).

RESULTS

A total of 218 patients (age 27 - 79, mean 60 ± 11; 193 females and 25 males) entered the analysis. For 211 of them (97 %), the radiologist was able to evaluate the images and determine an MR defecography-based diagnosis; in 7 patients (3 %), a diagnosis was not provided due to exam interruption for low patient's compliance. In 195/211 patients (92 %), the radiological diagnosis matched the clinical suspect that prompted the examination. The satisfaction about the diagnostic information given by the radiological report of the 211 exams was assessed by the surgeon as follows: excellent (n = 99, 47 %), good (n = 48, 23 %), sufficient (n = 35, 16 %), and insufficient (n = 29, 14 %). Out of 211 patients, 73 (34.6 %) underwent surgery. MR defecography provided concordant findings with relevant additional information in 63 (86.3 %), concordant findings with additional information in 3 (4.1 %), concordant findings without additional information in 4 (5.5 %), and discordant findings in 3 (4.1 %).

CONCLUSIONS

The diagnostic information prospectively provided by MR defecography resulted to be good or excellent in 70 % of the patients, adding clinical value in the preoperative surgical setting in 86 % of those patients who underwent surgery.

Effect of health education combined with biofeedback electrical stimulation on early pelvic floor function and psychology: A retrospective study

To investigate the effects of health education combined with biofeedback electrical stimulation on maternal postpartum pelvic floor function and psychology. The clinical data of 80 patients with postpartum pelvic floor dysfunction (PFD) from May 2020 to May 2022 were selected as retrospective study subjects, and 40 cases were divided into the comparison group and the observation group according to the different intervention methods. Among them, the comparison group implemented biofeedback electrical stimulation and guidance, and the observation group implemented Greene health education and Kegel pelvic floor rehabilitation training intervention based on the comparison group. The differences in pelvic floor muscle strength, sexual quality of life, anxiety, and depression in the 2 groups with postpartum PFD were compared. Comparison of pelvic floor muscle strength: before the intervention (P > .05) and after the intervention, the anterior resting mean electromyography (EMG), slow muscle mean EMG, fast muscle maximum EMG, and mixed muscle mean EMG values of patients in the observation group were higher than those in the comparison group, and the posterior resting mean EMG values were lower than those in the comparison group (P < .05). There was no statistically significant difference in the Hospital Anxiety and Depression Scale (HADS) scores and anxiety and depression subscale scores between the 2 groups of patients before intervention (P > .05). After the intervention, the HADS scores and anxiety and depression subscale scores were lower than those before the intervention in both groups, and the differences were statistically significant in the intervention group than in the comparison group (P < .05). There was no statistically significant difference between The Chinese Female Sexual Life Quality Questionnaire scores of both groups before the intervention (P > .05). Sexual desire, vaginal lubrication, sexual arousal, sexual satisfaction, orgasm, and painful intercourse improved in both groups after the intervention, and the scores in the intervention group were higher than those in the comparison group (P < .05). Health education combined with biofeedback electrical stimulation can effectively improve the quality of patients' sexual life, improve the pelvic floor muscle strength of patients with postpartum PFD, enhance patients' confidence, reduce patients' anxiety and depression, and effectively improve patients' psychological status.

Volumetric segmentation analysis of the levator ani muscle using magnetic resonance imaging in pelvic floor function assessment

PURPOSE

In this case-control study, we aimed to evaluate how muscle volume affects pelvic floor function by analyzing the levator ani muscle (LAM) using volumetric segmentation in addition to standard magnetic resonance (MR) defecography assessments.

METHODS

We enrolled 85 patients with varying degrees of pelvic floor dysfunction (PFD) and 85 age- and gender-matched controls in this retrospective study. All patients had MR defecography images, while all controls had pelvic MR images obtained for other reasons. Group comparisons were performed using independent samples t-tests and Mann-Whitney U tests. The receiver operating curve (ROC) was constructed to establish a cut-off value for a normal LAM volume. Interrater reliability was assessed by calculating the intraclass correlation coefficient. A P value of less than 0.05 was considered statistically significant.

RESULTS

Volumetric measurements revealed that the control group had higher LAM volumes, and the ROC curve analysis indicated a cut-off value of 38934.3 mm3 with a sensitivity of 0.812 and specificity of 0.8 for PFD assessment using LAM volumetric measurement. Gender did not significantly affect LAM volume in the control group.

CONCLUSION

Alongside the useful structural and functional information acquired from MR defecography images, volumetric analysis, and three-dimensional reconstructions of LAM may help to improve the accuracy of the diagnosis.

Quantitative 3D Analysis of Levator Ani Muscle Subdivisions in Nulliparous Women: MRI Feasibility Study

BACKGROUND

The levator ani muscle (LAM) is crucial for pelvic floor stability, yet its quantitative MRI assessment is only a recent focus. Our study aims to standardize the quantitative analysis of the LAM morphology within the 3D Pelvic Inclination Correction System (3D-PICS).

METHODS

We analyzed 35 static MR datasets from nulliparous women examining the pubovisceral (PVM), iliococcygeal (ICM), coccygeal (COC), and puborectal muscle (PRM). The PVM consists of three origin-insertion pairs, namely the puboanal (PAM), puboperineal (PPM) and pubovaginal muscle (PVaM). The analysis included a quantitative examination of the morphology of LAM, focusing on the median location (x/y/z) (x: anterior-posterior, y: superior-inferior, z: left-right) of the origin and insertion points (a), angles (b) and lengths (c) of LAM. Inter-rater reliability was calculated.

RESULTS

Interindividual variations in 3D coordinates among muscle subdivisions were shown. In all, 93% of all origin and insertion points were found within an SD of <8 mm. Angles to the xz-plane range between -15.4° (right PRM) and 40.7° (left PAM). The PRM is the largest pelvic muscle in static MRI. The ICC indicated moderate-to-good agreement between raters.

CONCLUSIONS

The accurate morphometry of the LAM and its subdivisions, along with reliable inter-rater agreement, was demonstrated, enhancing the understanding of normal pelvic anatomy in young nulliparous women.

Diagnostic Value of Dynamic Magnetic Resonance Imaging (dMRI) of the Pelvic Floor in Genital Prolapses

Pelvic organ prolapse is a chronic disease resulting from a weakening of the musculoskeletal apparatus of the pelvic organs. For the diagnosis of this pathology, it is insufficient to conduct only a clinical examination. An effective diagnostic tool is the method of dynamic magnetic resonance imaging (MRI) of the pelvic floor, which allows a comprehensive assessment of the anatomical and functional characteristics of the walls of the pelvis and pelvic organs. The aim of the study was to analyze the literature data on the possibilities and limitations of using dynamic MRI in pelvic organ prolapse. The widespread use of the dynamic MRI method is due to the high quality of the resulting image, good reproducibility, and the maximum ability to display the characteristics of the pelvic floor. Dynamic MRI of the small pelvis allows a comprehensive assessment of the anatomical and functional features of the pelvis, excluding the effect of ionizing radiation on the body. The method is characterized by good visualization with high resolution and excellent soft tissue contrast. The method allows for assessing the state of the evacuation function of visualized structures in dynamics. Simultaneous imaging of all three parts of the pelvic floor using dynamic MRI makes it possible to assess multicompartment disorders. The anatomical characteristics of the state of the pelvic organs in the norm and in the event of prolapse are considered. The technique for performing the method and the procedure for analyzing the resulting images are described. The possibilities of diagnosing a multicomponent lesion are considered, while it is noted that dynamic MRI of the pelvic organs provides visualization and functional analysis of all three parts of the pelvis and often allows the choice and correction of tactics for the surgical treatment of pelvic organ prolapse. It is noted that dynamic MRI is characterized by a high resolution of the obtained images, and the advantage of the method is the ability to detect functional changes accompanying the pathology of the pelvic floor.

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

INTRODUCTION AND HYPOTHESIS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Assessment of Pelvic Floor Disorders due to the Gestational Diabetes Mellitus Using Three-Dimensional Ultrasonography: A Narrative Review

Gestational diabetes mellitus (GDM)is an entity with evolving conceptual nuances that deserve full consideration. Gestational diabetes leads to complications and adverse effects on the mother's and infants' health during and after pregnancy. Women also have a higher prevalence of urinary incontinence (UI) related to the hyperglycemic status during pregnancy. However, the exact pathophysiological mechanism is still uncertain. We conducted a narrative review discussing the impact of GDM on the women's pelvic floor and performed image assessment using three-dimensional ultrasonography to evaluate and predict future UI.

Effects of Different Delivery Modes on Pelvic Floor Function in Parturients 6–8 Weeks after Delivery Using Transperineal Four-Dimensional Ultrasound

Objective

To evaluate the effects of different delivery modes on pelvic floor function in parturients 6–8 weeks after delivery using transperineal four-dimensional ultrasound.

Methods

Pelvic floor function 6–8 weeks after delivery in 40 vaginal delivery parturients between November 2018 and December 2020 was assessed by four-dimensional ultrasound, with 40 selective cesarean section delivery parturients as a control group. The imaging results of the two groups were compared.

Results

The levels of clinical indexes such as UVJ-M, A_r, A_v, θ, D_r, D_v, and ARJ-VDv in the selective cesarean section group were significantly lower than those in the vaginal delivery group 6–8 weeks after delivery (P < 0.05). However, no significant difference in CV-VD was observed under Valsalva action and at rest between the two groups (P > 0.05). No significant difference in ARJ-VD was found at rest between the two groups (P > 0.05). The incidence of pelvic organ prolapse in the selective cesarean section group (40.0%) was significantly lower than that in the vaginal delivery group (62.5%) (P < 0.05). No significant difference in the parameters of pelvic diaphragm hiatus at rest was observed between the two groups (P > 0.05). The parameters of pelvic diaphragm hiatus under maximum Valsalva action in the vaginal delivery group were significantly higher than those in the selective cesarean section group (P < 0.05). Whether the patient was complicated with diabetes had no significant effect on the functional injury of pelvic floor muscle (P > 0.05).

Conclusion

The pelvic floor function 6–8 weeks after delivery was significantly more affected in vaginal delivery than in selective cesarean section. Selective cesarean section had certain but limited protective effect on maternal pelvic floor tissue.

Deep learning-based pelvic levator hiatus segmentation from ultrasound images

Purpose

To automatically segment and measure the levator hiatus with a deep learning approach and evaluate the performance between algorithms, sonographers, and different devices.

Methods

Three deep learning models (UNet-ResNet34, HR-Net, and SegNet) were trained with 360 images and validated with 42 images. The trained models were tested with two test sets. The first set included 138 images to evaluate the performance between the algorithms and sonographers. An independent dataset including 679 images assessed the performances of algorithms between different ultrasound devices. Four metrics were used for evaluation: DSC, HDD, the relative error of segmentation area, and the absolute error of segmentation area.

Results

The UNet model outperformed HR-Net and SegNet. It could achieve a mean DSC of 0.964 for the first test set and 0.952 for the independent test set. UNet was creditable compared with three senior sonographers with a noninferiority test in the first test set and equivalent in the two test sets collected by different devices. On average, it took two seconds to process one case with a GPU and 2.4 s with a CPU.

Conclusions

The deep learning approach has good performance for levator hiatus segmentation and good generalization ability on independent test sets. This automatic levator hiatus segmentation approach could help shorten the clinical examination time and improve consistency.

Ultrasonographic Imaging of the Pelvic Floor

This article discusses various pelvic floor ultrasonographic modalities and the clinical applications of ultrasonography of the pelvic floor. Ultrasonography provides a detailed anatomic assessment of the muscles and surrounding organs of the pelvic floor. Different anatomic variabilities and pathologic conditions, such as prolapse, fecal incontinence, urinary symptoms, vaginal wall cysts, synthetic implanted material, and pelvic pain, are assessed with pelvic floor ultrasonography. This imaging modality is an important adjunct to the evaluation and diagnosis of pelvic floor disorders.

Clinical applications of pelvic floor imaging: opinion statement endorsed by the society of abdominal radiology (SAR), American Urological Association (AUA), and American Urogynecologic Society (AUGS)

Pelvic floor dysfunction is prevalent, with multifactorial causes and variable clinical presentations. Accurate diagnosis and assessment of the involved structures commonly requires a multidisciplinary approach. Imaging is often complementary to clinical assessment, and the most commonly used modalities for pelvic floor imaging include fluoroscopic defecography, magnetic resonance defecography, and pelvic floor ultrasound. This collaboration opinion paper was developed by representatives from multiple specialties involved in care of patients with pelvic floor dysfunction (radiologists, urogynecologists, urologists, and colorectal surgeons). Here, we discuss the utility of imaging techniques in various clinical scenarios, highlighting the perspectives of referring physicians. The final draft was endorsed by the Society of Abdominal Radiology (SAR), American Urogynecologic Society (AUGS), and the American Urological Association (AUA).

Pelvic floor assessment using magnetic resonance imaging after vaginal delivery and elective caesarean delivery

INTRODUCTION AND HYPOTHESIS

We aimed to compare quantitative static and dynamic magnetic resonance imaging (MRI) measurements of pelvic floor changes during postpartum recovery from 1 week to 6 months after different modes of delivery.

METHODS

In this prospective study, 51 primiparous women (vaginal delivery group: 30 women; elective caesarean delivery group: 21 women) underwent static and dynamic MRI at 1 week, 6 weeks, 3 months, and 6 months postpartum to measure pelvic floor MRI values. Between-group differences in pelvic floor values at these time points were determined; subsequently, within-group comparisons according to time were performed. Analysis included independent samples t-tests and paired t-tests.

RESULTS

The puborectal hiatus line (H line), muscular pelvic floor relaxation line (M line), bladder-pubococcygeal line (B-PCL), and uterus-pubococcygeal line (U-PCL) differed significantly between groups during the Valsalva manoeuvre at 1 week postpartum (p < 0.05). The H line, M line, and B-PCL values differed significantly between groups during the Valsalva manoeuvre at 6 weeks postpartum (p < 0.05). There were few significant between-group differences in pelvic floor values at 3 months and 6 months postpartum. In the vaginal delivery group, the differences in the H line and M line at 1 week, 6 weeks, and 3 months postpartum were significant (p < 0.001). In the elective caesarean delivery group, U-PCL differed significantly at 6 weeks compared to 1 week postpartum during the Valsalva manoeuvre (p < 0.05).

CONCLUSIONS

Pelvic floor recovery primarily occurred during the early phase after delivery in both groups. Elective caesarean delivery had a non-significant protective effect on postpartum pelvic floor structure and function compared to vaginal delivery.

MRI of the Male Pelvic Floor

The pelvic floor is a complex structure that supports the pelvic organs and provides resting tone and voluntary control of the urethral and anal sphincters. Dysfunction of or injury to the pelvic floor can lead to gastrointestinal, urinary, and sexual dysfunction. The prevalence of pelvic floor disorders is much lower in men than in women, and because of this, the majority of the published literature pertaining to MRI of the pelvic floor is oriented toward evaluation of the female pelvic floor. The male pelvic floor has sex-specific differences in anatomy and pathophysiologic disorders. Despite these differences, static and dynamic MRI features of these disorders, specifically gastrointestinal disorders, are similar in both sexes. MRI and MR defecography can be used to evaluate anorectal disorders related to the pelvic floor. MRI can also be used after prostatectomy to help predict the risk of postsurgical incontinence, to evaluate postsurgical function by using dynamic voiding MR cystourethrography, and subsequently, to assess causes of incontinence treatment failure. Increased tone of the pelvic musculature in men secondary to chronic pain can lead to sexual dysfunction. This article reviews normal male pelvic floor anatomy and how it differs from the female pelvis; MRI techniques for imaging the male pelvis; and urinary, gastrointestinal, and sexual conditions related to abnormalities of pelvic floor structures in men.Online supplemental material is available for this article.^©RSNA, 2019.

Urethral length and bladder neck behavior: can dynamic magnetic resonance imaging give the same results as introital ultrasound?

PURPOSE

To compare dynamic magnetic resonance imaging (dMRI) and introital ultrasound results with regard to urethral length measurements and the evaluation of bladder neck changes.

METHODS

Retrospective analyses of urethral length measurements and detection of bladder neck changes (rotated/vertical bladder neck descent, urethral funneling) were conducted in women-scheduled for surgical treatment with alloplastic material-who had undergone introital ultrasound and dMRI presurgery and 3 months postsurgery. Measurement differences between both imaging modalities were evaluated by assessing the confidence interval for the difference in means between the datasets using bootstrap analysis.

RESULTS

Based on data from 40 patients (320 image series), the urethra could be clearly measured on every pre- and postsurgical dMRI dataset but not on preoperative ultrasound images in nine women during Valsalva maneuver due to a large cystocele. The estimation of the mean difference distribution based on 500,000 bootstrap resamples indicated that the urethral length was measured shorter by dMRI pre- and postsurgery at rest and postsurgery during Valsalva maneuver (median 1.6-3.1 mm) but longer by dMRI (median 0.2 mm) during Valsalva maneuver presurgery. Rotated/vertical bladder neck descent and urethral funneling diagnoses showed concordance of 67-74% in the direct comparison of patients; the estimation of the concordance indicated poorer outcomes with 50-72%.

CONCLUSIONS

Metric information on urethral length from dMRI is comparable to that from introital ultrasound. dMRI is more advantageous in cases with an extended organ prolapse. At present, dMRI does not give the same diagnosis on bladder neck changes as introital ultrasound does.

The Engagement of the Pelvic Floor Muscles to the Urethra, Does Variation in Point of Action Exist?

Purpose: Lower urinary tract dysfunction (LUTD) occurs frequently in girls and may display a spinning top urethra (STU) on voiding cysto-urethrogram (VCUG) in case of dysfunctional voiding. A STU presents as a narrowing of the urethra caused by a lack of relaxation of the pelvic floor musculature during micturition and may vary in length between the proximal and the distal urethra. Although a STU has been recognized since 1960 as a pathological entity on VCUG, no reports exist on the different levels of engagement of the pelvic floor muscles to the urethra as expressed by the varying length of the phenomenon. The aim of our study is to demonstrate the wide anatomical variation in the level of engagement of the pelvic floor musculature to the urethra. Materials and Methods: Dynamic ultrasound videos of pelvic floor musculature of 40 girls with LUTD were reassessed by three observers, looking for the level of engagement of the puborectalis muscle (PRM) to the urethra during coughing, Valsalva and hold-up maneuver. Three levels were defined, for the level of engagement of the pelvic floor to the urethra, proximal, mid, and distal. Intra- and inter-rater variability was analyzed using Cohen's kappa statistics. Results: A wide range of points of action was found on the assessed ultrasound videos. Intra- and inter-rater agreement showed different levels of conformity, varying over a wide spectrum (intra-rater kappa 0.145-0.546; inter-rater kappa -0.1030.724). Throughout the assessed videos, all not-corresponding intra-rater observations differed maximal one category. Of the not-corresponding inter-rater observations, 90% differed maximal one category. Conclusion: An anatomical variation in levels of engagement of the PRM to the urethra does exist. The clinical value of this finding, whether the point of engagement influences symptomatology or treatment success of LUTD, is currently being studied.

Prospective evaluation of paravaginal defect repair with and without apical suspension: a 6-month postoperative follow-up with MRI, clinical examination, and questionnaires

INTRODUCTION AND HYPOTHESIS

Paravaginal defect (PVD) has been suggested as one of the main contributors to the development of prolapse in the anterior vaginal wall (AVW). We aimed to evaluate the descent of pelvic organs, presence of vaginal H configuration, and pubococcygeus (PC) muscle defect by pelvic magnetic resonance imaging (MRI), together with subjective symptoms of prolapse, before and 6 months after PVD repair. We also aimed to evaluate risk factors of recurrence.

METHODS

Fifty women with PVD diagnosed by gynecological examination and scheduled for vaginal PVD repair were planned for enrollment. Preoperatively and 6 months postoperatively, subjective symptoms were evaluated using the International Consultation on Incontinence Questionnaire-Vaginal Symptoms (ICIQ-VS) together with MRI of the pelvis to evaluate defects in the PC muscle, vaginal shape, and pelvic organ descent.

RESULTS

Forty-six women completed the study. Twenty had PVD repair alone, whereas 26 also had concomitant surgery performed. Prolapse grade, subjective symptoms, sexual problems, and quality of life (QoL) were significantly improved at follow-up. Missing vaginal H configuration was observed in 21 women before operation and was correlated with PC muscle defect. Recurrence rate was 39%, and significantly more women with recurrence had PC muscle defects and missing H configuration.

CONCLUSION

Vaginal PVD repair alone or combined with concomitant surgery significantly reduces objective prolapse and subjective symptoms. We could not demonstrate MRI findings of missing H configuration to be a sign of PVD but, rather, a sign of defect in the PC muscle. Risk of recurrence is significantly higher in women with major PC muscle defects and missing H configuration.

Use of Dynamic MRI of the Pelvic Floor in the Assessment of Anterior Compartment Disorders

PURPOSE OF REVIEW

Approximately 25% of women in the USA suffer from pelvic floor disorders. Disorders of the anterior compartment of the pelvic floor, in particular, can cause symptoms such as incomplete urinary voiding, urinary incontinence, pelvic organ prolapse, dyspareunia, and pelvic pain, potentially negatively impacting a woman's quality of life. In some clinical situations, clinical exam alone may be insufficient, especially when patient's symptoms are in excess of their pelvic exam findings. In many of these patients, dynamic magnetic resonance imaging (dMRI) of the pelvic floor can be a valuable imaging tool allowing for comprehensive assessment of the entire pelvic anatomy and its function.

RECENT FINDINGS

Traditionally, evaluation of the anterior compartment has been primarily through clinical examination with occasional use of urodynamic testing and ultrasound. In recent years, dMRI has continued to gain popularity due to its improved imaging quality, reproducibility, and ability to display the entire pelvic floor. Emerging evidence has also shown utility of dMRI in the postoperative setting. In spite of advances, there remains an ongoing discussion in contemporary literature regarding the accuracy of dMRI and its correlation with clinical examination and with patient symptoms. Dynamic pelvic MRI is a helpful adjunct to physical examination and urodynamic testing, particularly when a patient's symptoms are in excess of the physical examination findings. Evaluation with dMRI can guide preoperative and postoperative surgical management in many patients, especially in the setting of multicompartmental disorders. This review will summarize relevant pelvic floor anatomy and discuss the clinical application, imaging technique, imaging interpretation, and limitations of dMRI.