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

Assessment of defecation disorders using high-resolution MRI-defecography

AIMS

The aim of this retrospective study was to try to find correlations between different diagnoses established by clinical examination, anorectal manometry and MRI-defecography and, the association with psychiatric disorders.

METHODS

44 patients (median age 53.81 years) presenting with intestinal motility disorders and who underwent clinical, biological and psychiatric examination, dynamic defecographic-MRI (resting, squeezing, straining, defecation and evacuation phases), anorectal manometry, colonoscopy. MRI was performed using the 1,5 T.

RESULTS

MRI-defecography revealed the following changes: anismus (16), rectocele (12), pelvic floor dysfunction (6), peritoneocele (2), cervical-cystic-ptosis (1), rectal prolapse (6), and in 1 case the examination was normal. Hypertonic anal sphincter (16) and lack of defecation reflex (12) at anorectal manometry correlated with anismus in all patients at MRI-defecography. Lack of inhibitor anal reflex (6) was associated with rectocele (4), cervix-cysto-ptosis (1) and peritoneocele (2). Anxiety (11), depression (6) and anxiety-depressive disorders (10) were found in 27/44, somatization disorders in 9/44 and no psychiatric changes in 8/44 cases.

CONCLUSION

As multiparous women are at risk for outlet obstruction constipation, MRI-defecography is suggested in this category. There is good correlation between diagnosis using anorectal manometry and MRI-defecography in patients with terminal constipation and anismus. Lower defecation dysfunction is often associated with psychiatric disorders.

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.

Comparison of the anterior pelvis and levator ani muscle on MRI in women with and without anterior pelvic organ prolapse

INTRODUCTION AND HYPOTHESIS

The objective was to compare the differences in pelvic and levator ani muscle diameters in women with and without anterior pelvic organ prolapse.

METHODS

Three groups were included, including 50 nulliparous women (nulliparous group), 50 women with stage III-IV anterior vaginal prolapse (prolapse group), and 50 women of the same age as the prolapse group but without prolapse (nonprolapse control group). The ischial interspinous diameter (ISD), anterior pelvic area (APA), levator defect score (LDS), levator ani hiatus width (LH-W), H-line, M-line, levator ani plate length, levator ani plate angle, and cervix length (CL) were measured.

RESULTS

There were no significant differences in ISD (10.6±0.8 vs 10.6±0.9 cm), LH-W (3.0±0.4 vs 3.3±0.4 cm), or CL (2.9±0.6 vs 3.0±0.5 cm) between the nulliparous group and the nonprolapse control group (p>0.05). However, there were significant differences between them and the prolapsed group (11.2±0.6 cm, 3.6±0.4 cm, 4.2±1.5 cm; p<0.05). There were no significant differences in LDS (0.70±0.61 vs 0.70±0.65) or APA (58.4±8.4 vs 60.1±7.4 cm2) between the nonprolapse control group and the prolapse group (p>0.05), but they were significantly different from those of the nulliparous group (0.08±0.34, 55.1±6.0 cm2) (p<0.05). The area under the receiver-operating characteristic curve for the ISD of nonprolapse control and prolapse groups was 0.713, and the cutoff value was 10.95 cm.

CONCLUSIONS

The levator ani hiatus width and cervix length were larger in patients with anterior vaginal prolapse than in those without prolapse. An ischial ISD greater than 10.95 cm was associated with prolapse.

Comparison of the Perineal Body Between Chinese Women With Pelvic Organ Prolapse and Women With Normal Support by Magnetic Resonance Imaging With 3-Dimensional Reconstruction

OBJECTIVE

This study aimed to determine whether the perineal body (PB) is different between women with and without prolapse and to analyze its association with prolapse.

METHODS

This cross-sectional observational study was performed in a tertiary-level urology department and included patients with stage II-IV pelvic organ prolapse (POP) and normal controls with all points 1 cm or more above the hymen. The patients underwent supine midsagittal magnetic resonance imaging (MRI) at rest and during the maximum Valsalva maneuver. Perineal mobility and PB length, height, perimeter, and area were measured; in addition, the genital hiatus and PB were measured according to the definition of the Pelvic Organ Prolapse Quantification system. Univariate associations of POP with characteristics were assessed using the chi-square test or Fisher exact test for categorical variables and the t test for continuous variables. Multivariate logistic regression analysis was used to estimate the adjusted odds ratios and 95% confidence intervals.

RESULTS

Seventy-two controls and 130 patients were analyzed. The PB length, height, and area measurements were significantly lower in the POP group. The perineal mobility in different directions was significantly higher in the POP group. Multivariate analysis demonstrated that the PB area and perineal mobility in the ventral-dorsal and cranio-caudal directions were associated with POP.

CONCLUSIONS

Our data suggest that a smaller PB area and greater dorsal or caudal mobility are associated with prolapse.

Investigating the mechanism underlying urinary continence using dynamic MRI after Retzius-sparing robot-assisted radical prostatectomy

Retzius-sparing robot-assisted radical prostatectomy (RS-RARP) exhibits better postoperative urinary continence than conventional RARP (C-RARP) via the anterior approach. However, the reasons behind this are unknown. Herein, early postoperative urinary incontinence and anatomical differences of 51 propensity score-matched C-RARP and RS-RARP cases were compared. Dynamic magnetic resonance imaging (MRI) was performed before and after surgery to examine the pelvic anatomical changes under abdominal pressure. The median urine loss ratios in the early postoperative period after C-RARP and RS-RARP were 11.0% and 1.0%, respectively. Postoperative MRI revealed that the anterior bladder wall was fixed in a higher position after RS-RARP compared with its position after C-RARP. Dynamic MRI after C-RARP showed that cephalocaudal compression of the bladder while applying abdominal pressure caused the membranous urethra to expand and the urine to flow out. After RS-RARP, the rectum moved forward during abdominal pressure, and the membranous urethra was compressed by closure from behind. This is the first study using dynamic MRI to reveal the importance of high attachment of the anterior bladder wall for the urethral closure mechanism during abdominal pressure. RS-RARP, which can completely preserve this mechanism, is less likely to cause stress urinary incontinence compared with C-RARP.

Recent Advances in Computed Tomography and MR Imaging

Numerous advanced MR imaging and computed tomographic techniques have been developed and implemented in clinical practice over the past several years resulting in increased diagnostic accuracy and improved patient care. In this article, the authors highlight recent and emerging imaging techniques in functional and structural MR imaging, perfusion and vascular imaging, standardization of imaging practices, and selected applications of artificial intelligence in clinical practice.

Comparison of cervical length measured by POP-Q C-D and MRI: Why is POP-Q C-D not accurate?

OBJECTIVE

To investigate the relationship between the cervical length evaluated by Pelvic Organ Prolapse Quantification (POP-Q) point C minus D (C-D; ECL) and the magnetic resonance imaging (MRI)-based cervical length (MCL).

STUDY DESIGN

This was a retrospective study of patients with POP II-IV who underwent MRI. The ECL was calculated based on the absolute value of C-D according to POP-Q. The MCL was defined as the distance between the internal and external cervical os on MRI. Intraobserver reliability using the Bland-Altman method. Continuous variables were compared by paired 2-tailed t-tests. Multiple linear regression analysis was used to analyse the factors influencing differences between the ECL and MCL.

RESULTS

Among 105 eligible patients, 89 patients were eventually included in the study. The Bland-Altman scatter plots show that the intraobserver reliability of MCL was excellent. Furthermore, the mean ECL was significantly longer than the mean MCL (48.15 mm ± 27.46 vs. 28.25 mm ± 10.27, P = 0.000).Body mass index, parity, menopausal status or total vaginal length did not affect the difference between ECL and MCL. However, The larger the point Ba, the larger the difference between the ECL and MCL. The larger the point Bp, the smaller the difference between the ECL and MCL.

CONCLUSION

In general, POP-Q C-D was longer than the cervical length measured by MRI. Deep analysis found that when uterine prolapse is combined with larger anterior vaginal wall prolapse, the difference between ECL and MCL is greater; when uterine prolapse with larger posterior vaginal wall prolapse, the difference between ECL and MCL is smaller.