The role of the MR-fluoroscopy in the diagnosis and staging of the pelvic organ prolapse

MAGNETIC RESONANCE IMAGING OF PELVIC FLOOR DYSFUNCTION, REVIEW

Pelvic floor dysfunction is an important medical and social problem in the female population. The impact of pelvic floor disorders (PFD) is likely to grow as the prevalence of these disorders increases with an aging population. Pregnancy and delivery are considered major risk factors in the development of POP and stress urinary incontinence. Pelvic floor dysfunction may involve pelvic organ prolapse and/or pelvic floor relaxation. Organ prolapse can include any combination of the following: urethra (urethrocele), bladder (cystocele), or both (cystourethrocele), vaginal vault and cervix (vaginal vault prolapse), uterus (uterineprolapse), rectum (rectocele), sigmoid colon (sigmoidocele),and small bowel (enterocele).Given the paucity of understanding of PFD pathophysiology ,multicompartmental pathology, the high rate of recurrence and repeat surgery imaging plays a major role in its clinical management.The magnetic resonance imaging (MRI) allows noninvasive, radiation-free, rapid, high-resolution evaluation the multicompartment defects in one examination.Findings reported at MR imaging of the pelvic floor are valuable for selecting candidates for surgical treatment and for indicating the most appropriate surgical approach.

Integrated MR Analytical Approach and Reporting of Pelvic Floor Dysfunction: Current Implications and New Horizons

Reporting MR imaging of pelvic floor dysfunction can be made easy if radiologists understand the aim of each MR sequence and what to report in each set of MR images. For an MR imaging report that is critical in decision making for patient management, it is of paramount importance to the radiologist to know what to look for and where to look for it. This article presents a new term, integrated MR analytical approach. A reporting template is included in which all MR findings are presented in a schematic form that can be easily interpreted by clinicians from different subspecialties.

Magnetic resonance defecography versus clinical examination and fluoroscopy: a systematic review and meta-analysis

BACKGROUND

Magnetic resonance defecography (MRD) allows for dynamic visualisation of the pelvic floor compartments when assessing for pelvic floor dysfunction. Additional benefits over traditional techniques are largely unknown. The aim of this study was to compare detection and miss rates of pelvic floor abnormalities with MRD versus clinical examination and traditional fluoroscopic techniques.

METHODS

A systematic review and meta-analysis was conducted in accordance with recommendations from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. MEDLINE, Embase and the Cochrane Central Register of Controlled Trials were accessed. Studies were included if they reported detection rates of at least one outcome of interest with MRD versus EITHER clinical examination AND/OR fluoroscopic techniques within the same cohort of patients.

RESULTS

Twenty-eight studies were included: 14 studies compared clinical examination to MRD, and 16 compared fluoroscopic techniques to MRD. Detection and miss rates with MRD were not significantly different from clinical examination findings for any outcome except enterocele, where MRD had a higher detection rate (37.16% with MRD vs 25.08%; OR 2.23, 95% CI 1.21-4.11, p = 0.010) and lower miss rates (1.20 vs 37.35%; OR 0.05, 95% CI 0.01-0.20, p = 0.0001) compared to clinical examination. However, compared to fluoroscopy, MRD had a lower detection rate for rectoceles (61.84 vs 73.68%; OR 0.48 95% CI 0.30-0.76, p = 0.002) rectoanal intussusception (37.91 vs 57.14%; OR 0.32, 95% CI 0.16-0.66, p = 0.002) and perineal descent (52.29 vs 74.51%; OR 0.36, 95% CI 0.17-0.74, p = 0.006). Miss rates of MRD were also higher compared to fluoroscopy for rectoceles (15.96 vs 0%; OR 15.74, 95% CI 5.34-46.40, p < 0.00001), intussusception (36.11 vs 3.70%; OR 10.52, 95% CI 3.25-34.03, p = 0.0001) and perineal descent (32.11 vs 0.92%; OR 12.30, 95% CI 3.38-44.76, p = 0.0001).

CONCLUSIONS

MRD has a role in the assessment of pelvic floor dysfunction. However, clinicians need to be mindful of the risk of underdiagnosis and consider the use of additional imaging.

Magnetic resonance imaging of pelvic floor dysfunction - joint recommendations of the ESUR and ESGAR Pelvic Floor Working Group

OBJECTIVE

To develop recommendations that can be used as guidance for standardized approach regarding indications, patient preparation, sequences acquisition, interpretation and reporting of magnetic resonance imaging (MRI) for diagnosis and grading of pelvic floor dysfunction (PFD).

METHODS

The technique included critical literature between 1993 and 2013 and expert consensus about MRI protocols by the pelvic floor-imaging working group of the European Society of Urogenital Radiology (ESUR) and the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) from one Egyptian and seven European institutions. Data collection and analysis were achieved in 5 consecutive steps. Eighty-two items were scored to be eligible for further analysis and scaling. Agreement of at least 80 % was defined as consensus finding.

RESULTS

Consensus was reached for 88 % of 82 items. Recommended reporting template should include two main sections for measurements and grading. The pubococcygeal line (PCL) is recommended as the reference line to measure pelvic organ prolapse. The recommended grading scheme is the "Rule of three" for Pelvic Organ Prolapse (POP), while a rectocele and ARJ descent each has its specific grading system.

CONCLUSION

This literature review and expert consensus recommendations can be used as guidance for MR imaging and reporting of PFD.

KEY POINTS

• These recommendations highlight the most important prerequisites to obtain a diagnostic PFD-MRI. • Static, dynamic and evacuation sequences should be generally performed for PFD evaluation. • The recommendations were constructed through consensus among 13 radiologists from 8 institutions.

Interobserver agreement of multicompartment ultrasound in the assessment of pelvic floor anatomy

OBJECTIVE

To assess the interobserver agreement of pelvic floor anatomical measurements using multicompartment pelvic floor ultrasound.

METHODS

Females were recruited from the urogynaecology/gynaecology clinics between July and October 2009 and underwent multicompartment pelvic floor ultrasonography (PFUS) using two-dimensional (2D) transperineal ultrasound (TPUS), high-frequency 2D/three-dimensional (3D) endovaginal ultrasound (EVUS) using a biplane probe with linear and transverse arrays and a 360° rotational 3D-EVUS. PFUS measurements were independently analysed by two clinicians.

RESULTS

158 females had PFUS assessment. Good-to-excellent interobserver agreement was observed for bladder-symphysis distance at rest and valsalva, urethral thickness, urethral length, urethral volume, levator hiatus area and width, anteroposterior diameter and anorectal angle. Lins Correlation was used to calculate the interobserver agreement and Bland-Altman plots were created to demonstrate the agreement between the researchers. There was also a good-to-excellent agreement between the two clinicians for the assessment of pelvic organ prolapse (POP) in the anterior, middle and posterior compartment.

CONCLUSION

Multicompartment PFUS is a reliable tool in the anatomical assessment of pelvic floor measurements and POP.

ADVANCES IN KNOWLEDGE

We found a good-to-excellent agreement between the two assessors in the assessment of pelvic floor measurements for all three pelvic floor compartments and suggest that multicompartment PFUS could be considered as a systematic integrated approach to assess the pelvic floor.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

ADVANCES IN KNOWLEDGE

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

MRI findings before and after prolapse surgery

BACKGROUND

Therapeutical outcome after prolapse surgery is evaluated using a standardized grading system based on maximum prolapse extent, which might not provide the full picture of the patient's subjective outcome. We therefore applied an evaluation method, which is detached from a grading system.

PURPOSE

To evaluate the impact of pelvic organ mobility in dynamic magnetic resonance imaging (MRI) before and after mesh-repair surgery in patients with symptomatic pelvic organ prolapse.

MATERIAL AND METHODS

To obtain measurements, we performed parasagittal T2-weighted turbo spin echo sequence at rest (TR, 3460 ms; TE, 85 ms; matrix, 512; slice thickness [ST], 5 mm), parasagittal T2-weighted true fast imaging with steady-state precession (TrueFISP) single-shot sequence during straining (TR, 397.4 ms; TE, 1.5 ms; matrix, 256; ST, 8 mm), and parasagittal T2-weighted TrueFISP sequence at maximum strain (TR, 4.3 ms; TE, 2.15 ms; matrix, 256; ST, 5 mm) at 1.5 T MRI. Pelvic organ prolapse (anatomical landmarks: bladder, cervix, pouch, rectum) was measured perpendicularly with reference to the pubococcygeal and the midpubic line. Pelvic organ mobility was defined as the difference between the measured distance at rest and at maximum strain for each anatomical landmark. All patients underwent mesh-repair procedure. Eighty patients could be included in this short-term follow-up study. Due to the physical diagnosis of pelvic organ prolapse, 51 underwent anterior mesh repair, 16 underwent posterior mesh repair, and 13 underwent total mesh repair. Surgery was performed by one surgeon, using mesh implants from several manufacturers.

RESULTS

Median values of maximum organ prolapse for bladder, cervix, pouch, and rectum preoperatively were 2.54 cm, 0.33 cm, 2.47 cm, and 0.32 cm, respectively, and 12 weeks postoperatively 0.87 cm, -1.79 cm, 1.49 cm, and 0.49 cm, respectively. Highly significant improvement (P < 0.001) of pelvic organ mobility was observed in the treated compartment at 4- and 12-week follow-up. Physical evaluation 12 weeks after mesh-repair showed an asymptomatic POP-Q stage I, if any.

CONCLUSION

Dynamic MRI is useful in visualizing the maximum extent of pelvic organ prolapse, as the evaluation of pelvic organ mobility documents the intraindividual therapeutic outcome detached from a grading system based on maximal prolapse values.

Imaging pelvic floor disorders: trend toward comprehensive MRI

OBJECTIVE

The purpose of this article is to review the relevant anatomy and sonographic, fluoroscopic, and MRI options for evaluating patients with pelvic floor disorders.

CONCLUSION

Disorders of the pelvic floor are a heterogeneous and complex group of problems. Imaging can help elucidate the presence and extent of pelvic floor abnormalities. MRI is particularly well suited for global pelvic floor assessment including pelvic organ prolapse, defecatory function, and pelvic floor support structure integrity.

Dynamic magnetic resonance imaging for assessment of minimally invasive pelvic floor reconstruction with polypropylene implant

INTRODUCTION

The purpose of the study was to assess the usefulness of dynamic MRI in patients with pelvic organ prolapse after pelvic floor repair with polypropylene mesh.

MATERIALS AND METHODS

Fifteen consecutive patients (mean age 66.5 years) who were scheduled for either anterior (n=9) or posterior (n=6) pelvic floor repair were prospectively evaluated by clinical assessment and dynamic MRI 1 day before and 3 months after surgery. MRI diagnoses and MRI measurements of relevant anatomical points at rest and on straining were analysed before and after surgery.

RESULTS

At follow-up assessment 93.3% of all patients were clinically cured. Dynamic MRI showed newly developed (n=6) or increased (n=6) pelvic organ prolapse in 80% (n=12) of all patients 3 months after pelvic floor repair. Most of them (n=11; 91.7%) affected the untreated pelvic floor compartment. On straining anatomical points of reference in the anterior pelvic floor compartment were significantly (p<0.05) elevated after anterior repair and rectal bulging was significantly (p=0.036) reduced after posterior pelvic floor repair.

CONCLUSIONS

In this study dynamic MRI could verify the effective support of anterior and posterior pelvic floor structures by anterior and posterior polypropylene implant respectively. But dynamic MRI demonstrates if one compartment of the pelvic floor is repaired another compartment frequently (73.3%) develops dysfunction. These results did not correspond to clinical symptoms on short-term follow-up (3 months). Studies with long-term follow-up are necessary to prove if dynamic MRI can reliably identify clinically significant pelvic organ prolapse after pelvic floor repair before the onset of symptoms.

Comparison of supine magnetic resonance imaging with and without rectal contrast to fluoroscopic cystocolpoproctography for the diagnosis of pelvic organ prolapse

PURPOSE

To compare supine magnetic resonance imaging (MRI), with and without rectal contrast, with fluoroscopic cystocolpoproctography (CCP) for the diagnosis of pelvic organ prolapse.

MATERIALS AND METHODS

Supine MRI and CCP studies were reviewed in 82 patients. All patients were women with an average age of 58.8 years, and the studies were done a mean of 25 days apart. Magnetic resonance imaging was performed with rectal contrast (n = 35) and without rectal contrast (n = 47). Fluoroscopic cystocolpoproctography was performed with rectal (n = 82), vaginal (n = 82), small bowel (n = 81), and bladder (n = 78) contrast, and images were corrected for magnification. Each study was independently reviewed by 2 readers, and outcome variables were presence/absence of cystocele, vaginal prolapse, enterocele, sigmoidocele, and anterior rectocele. Sigmoidoceles were included with enteroceles for data analysis.

RESULTS

For the entire patient group, the prevalence of cystoceles was 89% on CCP and 80% on MRI; vaginal prolapse was 81% on CCP and 56% on MRI; enteroceles, 38% on CCP and 24% on MRI; and anterior rectoceles, 45% on CCP and 37% on MRI. There were significantly more cystoceles (odds ratio [OR] 4.7, P = 0.003), vaginal prolapses (OR 5.2, P < 0.0005), and enteroceles (OR 3.8, P< 0.0005) on CCP than on MRI. For MRI with rectal contrast versus CCP, the prevalence of cystoceles was 94% on CCP and 91% on MRI; vaginal prolapse, 74% on CCP and 70% on MRI; enteroceles, 36% on CCP and 19% on MRI; and anterior rectoceles, 51% on CCP and 59% on MRI. There was statistical significance only for enteroceles, more of which were found on CCP (OR 7.4, P = 0.003). For MRI without rectal contrast versus CCP, the prevalence of cystoceles was 85% on CCP and 72% on MRI; vaginal prolapse, 86% on CCP and 46% on MRI; enteroceles, 40% on CCP and 28% on MRI; and anterior rectoceles, 39% on CCP and 21% on MRI. There were significantly more cystoceles (OR 6.6, P = 0.003), vaginal prolapses (OR 20.8, P < 0.0005), enteroceles (OR 2.9, P = 0.015), and rectoceles (OR 4.9, P = 0.001) on CCP than on noncontrast MRI.

CONCLUSIONS

Magnetic resonance imaging without rectal contrast showed statistically fewer pelvic floor abnormalities than CCP. Except for enteroceles, MRI with rectal contrast showed statistically similar frequency of pelvic organ prolapse as CCP.

A systematic review of clinical studies on dynamic magnetic resonance imaging of pelvic organ prolapse: the use of reference lines and anatomical landmarks

INTRODUCTION AND HYPOTHESIS

The aim of our study was to provide a systematic literature review of clinical studies on pelvic organ prolapse staging with use of dynamic magnetic resonance (MR) imaging.

METHODS

The databases EMBASE and PubMed were searched. Clinical studies were included in case they compared pelvic organ prolapse stages as assessed on dynamic MR imaging (using a reference line) with a standardized method of clinical prolapse staging.

RESULTS

Ten studies were included, which made use of seven different reference lines in relation to a wide variety of anatomical landmarks.

CONCLUSION

Only few studies have compared pelvic organ prolapse stages as assessed by dynamic MR imaging and clinical examination in a standardized manner. The available evidence suggests that prolapse assessment on dynamic MR imaging may be useful in the posterior compartment, but clinical assessment and dynamic MR imaging seem interchangeable in the anterior and central compartment.

Magnetic resonance assessment of pelvic anatomy and pelvic floor disorders after childbirth

To compare pelvic anatomy, using magnetic resonance imaging, between postpartum women with or without pelvic floor disorders. We measured postpartum bony and soft tissue pelvic dimensions in 246 primiparas, 6-12-months postpartum. Anatomy was compared between women with and without urinary or fecal incontinence, or pelvic organ prolapse; P < 0.01 was considered statistically significant. A deeper sacral hollow was significantly associated with fecal incontinence (P = 0.005). Urinary incontinence was marginally associated with a wider intertuberous diameter (P = 0.017) and pelvic arch (P = 0.017). There were no significant differences in pelvimetry measures between women with and without prolapse (e.g., vaginal or cervical descent to or beyond the hymen). We did not detect meaningful differences in soft tissue dimensions for women with and without these pelvic floor disorders. Dimensions of the bony pelvis do not differ substantially between primiparous women with and without postpartum urinary incontinence, fecal incontinence and prolapse.

Dynamic magnetic resonance imaging for grading pelvic organ prolapse according to the International Continence Society classification: which line should be used?

AIMS

To assess and compare the reliability of dynamic MRI to quantify pelvic organ prolapse (POP) according to the International Continence Society (ICS) using two different reference lines, and to determine which line gives the best concordance with clinical examination.

METHODS

Forty-seven patients with genital prolapse underwent physical examination and dynamic MRI. Five nulliparous, symptom-free female volunteers underwent dynamic MRI as control subjects. Two distinct observers performed the MRI measurements of POP according to the ICS using two distinct reference lines: the mid-pubic line and a new one, the perineal line that provides a better match with the hymen plane. Measurements were repeated twice according to each line. The intra-class coefficient was used to estimate intra-observer and inter-observer reliability; the Altman and Bland plot was used to assess the agreement between MRI and clinical measurements.

RESULTS

The intra-observer and inter-observer reliability of MRI measurements were in general excellent. Intra-class coefficients were better for the mid-pubic line than the perineal line. Although the MRI measurements correlate significantly with the physical measurements, the Altman and Bland plot shows an unacceptable magnitude of discrepancy between clinical and MRI examinations.

CONCLUSIONS

Although dynamic MRI shows excellent inter- and intra-observer reliability, its agreement with clinical examination is poor whatever the line used.

Dynamic magnetic resonance imaging used in evaluation of female pelvic prolapse: experience from nine cases

Prolapse of pelvic organs in a female can be simple or complex. To make a definite diagnosis of pelvic prolapse preoperatively, dynamic magnetic resonance (MR) is an alternative to conventional fluoroscopic or sonographic examination, with the advantage of providing greater details, and thus helping the surgeon to have a good preoperative plan. Nine women suffering from pelvic prolapse with or without urinary stress incontinence underwent dynamic MR imaging examination (1.0T Magnex100/HP, Shimadzu, Kyoto, Japan) before surgery. All patients were examined in the supine position. A single-shot ultra-high speed scan (FE/8/3.02-20 degrees, 128, 100%-100% 1 NEX 1 slice 10 mm L1.0 second) was used to obtain midline sagittal images, with the patients at rest and during pelvic strain. MR images were then obtained every 4 seconds. Each examination was analyzed, based on specific measurements, to determine the presence and extent of prolapse of pelvic organs. The pubococcygeal, levator hiatus width and muscular pelvic floor relaxation lines, and the angle of the levator plate were identified. Based on these measurements, multicompartment involvement in the pelvic prolapse was confirmed in five patients (5/9). Four patients (4/9) had single compartment involvement. Seven patients underwent surgery. All patients reported significant improvement in their symptoms and signs after surgical intervention. Two patients had an almost complete recovery. MR demonstrated simple or complex organ descent in all pelvic compartments, and may become a standard preoperative examination for pelvic floor abnormalities. The MR images facilitated comprehensive planning by the surgeon; thus, they can increase the success rate and help to accurately predict the outcome of the surgical intervention. The surgeons also expressed high postsurgical satisfaction with the information provided by dynamic MR.

Anterior vaginal wall length and degree of anterior compartment prolapse seen on dynamic MRI

The objective of the study was to determine the relationship between midsagittal vaginal wall geometric parameters and the degree of anterior vaginal prolapse. We have previously presented data indicating that about half of anterior wall descent can be explained by the degree of apical descent present (Summers et al., Am J Obstet Gynecol, 194:1438-1443, 2006). This led us to examine whether other midsagittal vaginal geometric parameters are associated with anterior wall descent. Magnetic resonance (MR) scans of 145 women from the prior study were suitable for analysis after eight were excluded because of inadequate visibility of the anterior vaginal wall. Subjects had been selected from a study of pelvic organ prolapse that included women with and without prolapse. All patients underwent supine dynamic MR scans in the midsagittal plane. Anterior vaginal wall length, location of distal vaginal wall point, and the area under the midsagittal profile of the anterior vaginal wall were measured during maximal Valsalva. A linear regression model was used to examine how much of the variance in cystocele size could be explained by these vaginal parameters. When both apical descent and vaginal length were considered in the linear regression model, 77% (R (2) = 0.77, p < 0.001) of the variation in anterior wall descent was explained. Distal vaginal point and a measure anterior wall shape, the area under the profile of the anterior vaginal wall, added little to the model. Increasing vaginal length was positively correlated with greater degrees of anterior vaginal prolapse during maximal Valsalva (R (2) = 0.30, p < 0.01) determining 30% of the variation in anterior wall decent. Greater degrees of anterior vaginal prolapse are associated with a longer vaginal wall. Linear regression modeling suggests that 77% of anterior wall descent can be explained by apical descent and midsagittal anterior vaginal wall length.

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.