Magnetic resonance imaging of the pelvic floor

MR Imaging in Diagnosis of Pelvic Floor Descent: Supine versus Sitting Position

Introduction. Functional disorders of the pelvic floor represent have a significant impact on the quality of life. The advent of open-configuration systems allowed for the evaluation of defecation with MR imaging in sitting position. The purpose of the present study is to compare the results of static and dynamic pelvic MR performed in supine position versus sitting position, using a new MR prototype machine, in the diagnosis of pelvic floor descent. Materials and Methods. Thirty-one patients with pelvic floor disorders were enrolled, and underwent MR Defecography in supine position with 1.5 T closed magnet (MAGNETOM Symphony, Siemens, Germany) and in sitting position with a 0.25-Tesla open magnet system (G-Scan ESAOTE, Italy). Results. In rest and squeezing phases, positions of bladder, vagina, and ARJ were significantly different when the patient was imaged in supine versus sitting position. In the defecation phase, a significant difference for the bladder and vagina position was detected between the two exams whereas a significant difference for the ARJ was not found. A statistically significant difference exists when the pelvic floor descent is evaluated in sitting versus supine position. Conclusion. Our results show that MR Defecography in sitting position may represent a useful tool to correctly diagnose and grade the pelvic organ descent.

Pelvic tumors with normal-appearing shapes of ovaries and uterus presenting as an emergency (Review)

Abdominal pain with an associated pelvic mass is a common problem in everyday practice. Concerns about ectopic pregnancy, torsion of an enlarged ovary or malignancy usually dominate the diagnostic evaluation. On physical and imaging examination, when a palpable painful mass is present in the pelvis and the two ovaries and uterus are detected in their normal anatomical locations, the content and origin of the lesions may be significant in narrowing the pre-operative differential diagnosis. Thus, the emergent pelvic indications discussed in this review should be considered. The causes of acute abdominal pain are few in number and therefore an accurate diagnosis may be most frequently made at the time of exploratory laparotomy.

Pelvic floor imaging: comparison between magnetic resonance imaging and conventional defecography in studying outlet obstruction syndrome

PURPOSE

This study prospectively compared the diagnostic capabilities of magnetic resonance (MR) imaging with conventional defecography (CD) in outlet obstruction syndrome.

MATERIALS AND METHODS

Nineteen consecutive patients with clinical symptoms of outlet obstruction underwent pelvic MR examination. The MR imaging protocol included static T2-weighted fast spin-echo (FSE) images in the sagittal, axial and coronal planes; dynamic midsagittal T2-weighted single-shot (SS)-FSE and fast imaging employing steady-state acquisition (FIESTA) cine images during contraction, rest, straining and defecation. MR images (including and then excluding the evacuation phase) were compared with CD, which is considered the reference standard.

RESULTS

Comparison between CD and MR with evacuation phase (MRWEP) showed no significant differences in sphincter hypotonia, dyssynergia, rectocele or rectal prolapse and significant differences in descending perineum. Comparison between CD and MR without evacuation phase (MRWOEP) showed no significant differences in sphincter hypotonia, dyssynergia or enterocele but significant differences in rectocele, rectal prolapse and descending perineum. Comparison between MRWEP and MRWOEP showed no significant differences in sphincter hypotonia, dyssynergia, enterocele or descending perineum but significant differences in rectocele, rectal prolapse, peritoneocele, cervical cystoptosis and hysteroptosis.

CONCLUSIONS

MR imaging provides morphological and functional study of pelvic floor structures and may offer an imaging tool complementary to CD in multicompartment evaluation of the pelvis. An evacuation phase is mandatory.

Role of static and dynamic MR imaging in surgical pelvic floor dysfunction

Pelvic floor dysfunction (PFD) is a hidden women's health epidemic in the United States, with over 10% of women having a lifetime risk for undergoing a surgical repair for this problem. Given the paucity of understanding of PFD pathophysiology and the high rate of recurrence and repeat surgery, imaging plays a major role in its clinical management, especially for the preoperative assessment of patients with multicompartment defects and failed surgical repairs. The recent development of fast magnetic resonance (MR) imaging sequences allows noninvasive, radiation-free, rapid, high-resolution evaluation of the entire pelvis in one examination. The H line, M line, organ prolapse (HMO) classification system, which is applied to dynamic MR images, allows consistent standardization and grading of various forms of PFD. In addition, the HMO system clearly defines and differentiates between the two main components of PFD: pelvic floor relaxation and pelvic organ prolapse. In addition to serving as an objective diagnostic tool in patients with surgical PFD, MR imaging has tremendous potential to be used as a research tool in trying to understand the pathophysiology of these complex disorders.

Radiologic evaluation of pelvic floor disorders

Several imaging modalities are available ranging from fluoroscopic techniques to ultrasonography and MRI for the evaluation of patients with pelvic floors disorders. High-resolution ultrasonography and MRI not only provide superior delineation of the pelvic floor anatomy but also reveal pathology and functional changes. This article focuses on standard imaging procedures including defecography, ultrasonography, and MRI and discusses its use in clinical practice by illustrating both normal and abnormal patterns.

[MRI in static and dynamic disfunction of the female floor]

MRI is taking a growing place for pelvic prolapse diagnosis. A strict technical protocol with static and dynamic sequences is required with rectal and vaginal ultrasound gel. A good knowledge of physiology and anatomy of pelvic and perineal muscles is mandatory as well as a clinical approach of various pathologic prolapses. MRI fundings are presented and correlated with several clinical situations of prolapse and post operative features.

MR imaging evaluation of the pelvic floor for the assessment of vaginal prolapse and urinary incontinence

Pelvic MR imaging using the combination of motion-insensitive T2-weighted single-shot fast spin echo and high soft tissue resolution standard T2-weighted fast spin echo techniques has helped to identify soft tissue abnormalities that directly correlate with the clinical and intraoperative findings related to pelvic floor prolapse. In particular, the authors have shown that pelvic MR imaging has the ability to identify changes related to uterosacral ligament disruption and to document the corrective changes after surgical repair of this ligament. In the future, pelvic MR imaging is expected to play a progressively larger role in preoperative planning for complex or uncertain cases and for more detailed evaluation of repair in cases that do not show good symptomatic response. Pelvic MR imaging should also help to document and advance knowledge of surgical repair methodology.

Pelvic prolapse: static and dynamic MRI

Pelvic magnetic resonance is a simple and non-invasive imaging technique for dynamic and static assessment of the pelvic floor. The morphology of the support system is assessed by T2-weighted images. Dynamic sequences are used to assess pelvic prolapse. In this study we illustrate the normal and pathologic features of the levator ani muscle which represents the main active support of pelvic organs. Furthermore we describe the different types of prolapses, floor by floor, and the different staging techniques.

Anatomical and functional significance of urogenital hiatus in primary urodynamic stress incontinence

OBJECTIVES

To explore the correlations of anatomical and functional sonographic parameters of urogenital hiatus in primary urodynamic stress incontinence.

METHODS

We reviewed retrospectively our urodynamic database from July 1996 to June 2003 and identified subjects with primary urodynamic stress incontinence who had had anatomical assessment of the lower urinary tract and the central part of the pelvic floor by ultrasound. The morphological changes that had occurred in the central pelvic floor were determined by the measurement of genitohiatal angle, genitohiatal distance and anorectal angle.

RESULTS

A total of 396 women with a mean age of 48.8 +/- 10.7 (range, 26-82) years were included in the study. One hundred and eighteen subjects (29.8%) were postmenopausal. Stage I pelvic organ prolapse was found in 345 (87.1%) of the women, stage II in 19 (4.8%) and stage III in 32 (8.1%). The genitohiatal angle and genitohiatal distance were significantly and positively associated with resting and straining bladder neck angles. The genitohiatal angle was associated with bladder neck funneling and dependent cystocele during stress (r = 0.144, P = 0.016 and r = 0.140, P = 0.02, respectively), and it was negatively associated with functional profile length (r = -0.157, P = 0.012). The genitohiatal distance was negatively associated with functional profile length and maximum urethral closure pressure (r = -0.148, P = 0.018 and r = -0.227, P = 0.009, respectively). Increased genitohiatal distance was also related to a low Valsalva leak-point pressure (r = -0.199, P = 0.02). Multivariate analysis revealed that resting bladder neck angle was the independent factor for genitohiatal angle and genitohiatal distance.

CONCLUSIONS

In primary urodynamic stress incontinence, an increased resting genitohiatal distance or genitohiatal angle on sonographic imaging implies anterior vaginal wall prolapse. In addition, an increased genitohiatal distance is associated with functional impairment of urethral closure.