Magnetic Resonance Defecography Research Articles

MR defecography in assessing stress urinary incontinence with or without symptomatic pelvic organ prolapse.

Utilize magnetic resonance defecography (MRD) to analyze the primary pelvic floor dysfunctions in patients with stress urinary incontinence (SUI) associated with pelvic organ prolapse (POP), and in SUI patients with asymptomatic POP. We performed MRD in both SUI and POP subjects. As a primary analysis, the functional MR parameters were compared between the isolated POP and POP combined SUI groups. As a secondary analysis, the functional MR data were compared between the POP combined SUI and the SUI with asymptomatic POP (isolated SUI) groups. MRD noted the main characteristics of SUI combined moderate or severe POP, including the shorter closed urethra length (1.87cm vs. 2.50cm, p < 0.001), more prevalent urethral hypermobility (112.31° vs. 85.67°, p = 0.003), bladder neck funneling (48.28% vs. 20.51%, p = 0.020), lower position of vesicourethral junction (2.11cm vs. 1.67cm, p = 0.030), and more severe prolapse of the posterior bladder wall (6.26cm vs. 4.35cm, p = 0.008). The isolated SUI patients showed the shortest length of the closed urethra (1.56cm vs. 1.87cm, p = 0.029), a larger vesicourethral angle (153.80° vs. 107.58°, p < 0.001), the more positive bladder funneling (84.85% vs. 48.28%, p = 0.002) and a special urethral opening sign (45.45% vs. 3.45%, p < 0.001). Patients with SUI accompanying POP primarily exhibit excessive urethral mobility and a shortened urethral closure. SUI patients with asymptomatic POP mainly show dysfunction of the urethra and bladder neck, characterized by the opening of the urethra and bladder neck and a shortened urethral closure.

A new dıagnostic tool for assessment of pelvıc dysfunction ın MR defecography.

Pelvic floor dysfunction is characterized by incomplete fecal defecation, affecting quality of life in a negative way. Magnetic resonance defecography (MRD) is a useful examination that is ionizing radiation-free and easily reproducible, and which provides anatomical and functional details that are obtainable through multiplanar and dynamic examinations. We aimed to detect pathology using MRD in patients with suspected pelvic floor dysfunction and determine its cause. MRD was performed in 79 individuals. Dynamic images were obtained at rest, straining, and during defecation. Pelvic hiatus mediolateral diameters were compared between groups. Defecation phase provided significantly more accurate results than the straining phase for determining the existence and severity of pathology. Conclusıons: The defecation phase is the most accurate phase for identifying the existence and severity of pathology. As the pelvic hiatus mediolateral diameter is thought to be an important factor in triggering pelvic dysfunction.

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

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. 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. 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. 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.

Pubococcygeal Line Versus H-line as MR Defecography Reference for Bladder Descent.

Magnetic resonance defecography imaging techniques have been used widely to study pelvic floor function and diagnose pelvic organ prolapse (POP). The aim of this study was to investigate the diagnostic accuracy of the H-line to detect bladder descent compared with the current landmark, the pubococcygeal line (PCL). In this retrospective cohort study, patients who underwent MR defecography in our medical center and were diagnosed with moderate to severe cystocele by radiological measurements were recruited. One rest image and one maximum evacuation image for each subject were used for the following measurements: bladder base perpendicular distance from the genital hiatus (GH), indicative of clinically significant bladder descent, PCL as the current radiological reference line, and the H-line, or minimal levator hiatus line, indicative of pelvic floor muscle and connective tissue support.Subjects were categorized as having clinically significant cystocele if the "bladder base" reached within 1 cm or lower of the GH (stage II or higher cystocele). A comparison was performed to assess differences and predictive capabilities of the reference lines relative to the GH measure. Seventy subjects were included, 30 with clinically significant bladder descent based on distance to GH. Women with bladder descent were older (64.0 ± 11.8 vs 51.2 ± 15.6, p < 0.001), had increased parity (3 [1-7] vs 2 [0-5], p = 0.009), and had a bladder that descended lower than the H-line at rest (1.9 ± 0.5 vs 2.2 ± 0.4, p = 0.003) and evacuation (-2.4 ± 1.6 vs -0.7 ± 1.1, p < 0.001). Multivariate regression analysis confirmed that age, length of the H-line at evacuation, the perpendicular distances between the H-line and the lowest bladder point at rest, and the PCL to the lowest bladder point at evacuation significantly correlated with bladder descent.Receiver operating characteristic analysis was used to identify a measurement threshold to diagnose clinically significant cystocele for both measurements, bladder base to the H-line: -1.2 (80.0, 72.5) area under the curve (AUC) 0.82, and bladder base PCL: -3.3 (77.8, 79.5) AUC 0.86. Our data support the application of using the minimal levator hiatus plane and specifically the H-line as a reliable landmark to diagnose bladder descent using MR defecography imaging.

Comparison of Dynamic Magnetic Resonance Defecography With Clinical Examination in Diagnosing Pelvic Floor Dysfunction: An Observational Study.

Pelvic floor dysfunction (PFD) is frequently reported in both sexes. Dynamic magnetic resonance defecography (DMRD) is the preferred modality, mainly due to its superiority and complementary role in clinical examination. However, studies from the perspective of Indian patients are scarce and mostly restricted to females. Thus, we assessed the diagnostic performance of DMRD in patients with PFD and correlated the findings with those on clinical examination. This prospective, observational study involved 57 adult patients of either sex, presenting with pelvic floor symptoms (PFS) and diagnosed with PFD. Initially, the patients underwent clinical examination, and diagnosis was recorded. Subsequently, the patients were subjected to DMRD. The findings were correlated with the Pearson "r" correlation coefficient. A significantly greater proportion of patients had involvement of multiple compartments (36 vs. 12, p<0.001), cystocele (23 vs. 8, p=0.002), and rectal prolapse (25 vs. 14, p=0.030) on DMRD than clinical examination, while there was no significant difference regarding uterine prolapse (p=0.789). Grading of cystocele and rectal prolapse as well as diagnosis of enterocele/peritoneocele, rectocele, and intussusception could be done only with DMRD. DMRD had a strong and significant correlation with clinical examination regarding cystocele (r=0.943, p=0.003), uterine prolapse (r=0.972, p=0.001), and rectal prolapse (r=0.951, p=0.001). DMRD demonstrated significantly better performance in the diagnosis of multiple compartmentinvolvement, cystocele, and rectal prolapse. DMRD and clinical examination were significantly correlated regarding the diagnosis of cystocele, uterine prolapse, and rectal prolapse. Thus, DMRD provides information, in addition to the clinical examination, and should be used in symptomatic patients.

Increased Grades of Rectal Intussusception: Role of Decline in Pelvic Floor Integrity and Association With Dyssynergic Defecation.

The natural history of rectal intussusception (RI) is poorly understood. We hypothesized that decline in pelvic floor integrity and function leads to increasing RI grades. Retrospective analysis of a registry of patients with defecatory disorders with high-resolution anorectal manometry and magnetic resonance defecography was performed. Association of risk factors on increasing RI grades was assessed using logistic regression. Analysis included a total of 238 women: 90 had no RI, 43 Oxford 1-2, 49 Oxford 3, and 56 Oxford 4-5. Age ( P = 0.017), vaginal delivery ( P = 0.008), and prior pelvic surgery ( P = 0.032) were associated with increased Oxford grades. Obstructive defecation symptoms and dyssynergic defecation were observed at relatively high rates across groups. Increased RI grades were associated with less anal relaxation at simulated defecation yet, higher rates of normal balloon expulsion ( P < 0.05), linked to diminished anal sphincter. Indeed, increased RI grades were associated with worsening fecal incontinence severity, attributed to higher rates of anal hypotension. Levator ani laxity, defined by increased levator hiatus length and its excessive descent at straining, was associated with increasing RI grades, independent of age, history of vaginal delivery, and pelvic surgeries and could independently predict increased RI grades. Concurrent anterior and posterior compartments, and visceral prolapse were associated with higher Oxford grades. Our data suggest that decline in pelvic floor integrity with abnormal levator ani laxity is associated with increased RI grades, a process that is independent of age, history of vaginal deliveries, and/or pelvic surgeries, and perhaps related to dyssynergic defecation.

Imaging of the pelvic floor (MR defecography) : The surgeon's perspective

Magnetic resonance defecography (MRD) plays acentral role in diagnosing pelvic floor functional disorders by visualizing the entire pelvic floor along with pelvic organs and providing functional assessment of the defecation process. Ashared understanding between radiology and surgery regarding indications and interpretation of findings is crucial for optimal utilization of MRD. This review aims to explain the indications for MRD from asurgical perspective and elucidate the significance of radiological findings for treatment. It intends to clarify for which symptoms MRD is appropriate and which criteria should be followed for standardized results. This is prerequisite to develop interdisciplinary therapeutic approaches. Acomprehensive literature search was conducted, including current consensus guidelines. MRD can provide relevant findings in the diagnosis of fecal incontinence and obstructed defecation syndrome, particularly in cases of pelvic floor descent, enterocele, intussusception, and pelvic floor dyssynergia. However, rectocele findings in MRD should be interpreted with caution in order to avoid overdiagnosis. MRD findings should never be considered in isolation but rather in conjunction with patient history, clinical examination, and symptomatology since morphology and functional complaints may not always correlate, and there is wide variance of normal values. Interdisciplinary interpretation of MRD results involving radiology, surgery, gynecology, and urology, preferably in the context of pelvic floor conferences, is recommended.

Utilization of Rectal Examinations Before Magnetic Resonance Defecography Studies.

More information is needed to guide referring subspecialists on the appropriate patient evaluation before magnetic resonance defecography (MRD). This study aimed to evaluate how often health care providers perform digital rectal examination (DRE) before ordering MRD to investigate causes of bowel and pelvic floor complaints. We conducted a retrospective cohort review, including MRD performed on female patients at an integrated health care system from 2016 through 2020. The primary outcome was the presence or absence of documented rectal examination in the year before defecography by the referring provider or 6 months prior by a primary care physician or pelvic floor physical therapist. We hypothesized that the overall rate of rectal examination would be high and unaffected by the referring provider's subspecialty. Three hundred-four defecography tests were performed, with 209 patients (68.8%) referred by gastroenterology providers and 95 (31.2%) from other specialties. Gastroenterologists performed DRE in 32.8% of patients, in contrast to 84.4% of patients referred by other specialties ( P < 0.001). When comparing subspecialties that most commonly refer patients for MRD (gastroenterology, colorectal surgery and urogynecology), there was a statistically significant difference between gastroenterologists and colorectal surgeons ( P < 0.001) as well as urogynecologists ( P < 0.001) but no difference in the rate of rectal examination between colorectal surgeons and urogynecologists ( P = 1.00). At our single integrated health system, the rate of DRE before MRD testing varied significantly by specialty. Our findings highlight the need for better understanding of DRE utility in the algorithms for evaluation of bowel and pelvic floor disorders.

Diagnostic performance of dynamic MR defecography in assessment of dyssynergic defecation.

To assess diagnostic performance of MR defecographic findings in diagnosis of dyssynergic defecation (DD). This retrospective study included 46 patients with chronic constipation who met the Rome IV criteria for diagnosis of present or absent DD and underwent MRI between Jan 2015 and June 2020. Patients were divided into DD group (n = 24) and non-DD group (n = 22). Nine parameters were analyzed by two radiologists: anorectal angle (ARA) and M line at rest, defecation, and change between 2 phases; anal canal width; prominent puborectalis muscle; abnormal evacuation. Receiver operating characteristic (ROC) curves were plotted to extract the optimal cut-offs and area under the curve (AUC). Multivariate analysis was performed. Seven findings showed statistically significant difference between DD and non-DD groups. M line at defecation had highest odds ratio, followed by ARA change, ARA at defecation, M line change, prominent puborectalis muscle, abnormal evacuation and anal canal width, respectively. ARA change and prominent puborectalis muscle had highest specificity (95.5% and 100%, respectively). The optimal cut-offs of ARA at defecation, ARA change, M line at defecation, M line change and anal canal width were 122°, 1.5°, 3.25cm, 1.9cm and 8.5mm, respectively. Multivariate logistic regression revealed two significant findings in differentiating between DD and non-DD, including M line at defecation (OR 23.31, 95% CI 3.10-175.32) and ARA at defecation (OR 13.63, 95% CI 1.94-95.53) with sensitivity, specificity, PPV, NPV and AUC of 79.2%, 95.5%, 95%, 80.8% and 0.87(95% CI 0.78-0.97), respectively. MR defecography has high diagnostic performance in diagnosis of DD. Although M line and ARA at defecation are two significant findings on multivariate analysis, ARA change less than 1.5 degrees and prominent puborectalis muscle have good specificity in DD diagnosis.

Robot-Assisted Sacrocolpopexy versus Trans-Vaginal Multicompartment Prolapse Repair: Impact on Lower Bowel Tract Function.

This study evaluated the effectiveness, safety, and possible changes in bowel symptoms after multicompartment prolapse surgery by comparing two different surgical approaches, transvaginal mesh surgery with levatorplasty (TVMLP) and robot-assisted sacrocolpopexy (RSC). All patients underwent pelvic (POP-Q staging system) and rectal examination to evaluate anal sphincter tone in the lithotomy position with the appropriate Valsalva test. The preoperative evaluation included urodynamics and pelvic magnetic resonance defecography. Patient Global Impression of Improvement (PGI-I) at follow-up measured subjective improvement. All patients completed Agachan-Wexner's questionnaire at 0 and 12 months of follow-up to evaluate bowel symptoms. A total of 73 cases were randomized into the RSC group (36 cases) and TVMLP group (37 cases). After surgery, the main POP-Q stage in both groups was stage I (RCS 80.5% vs. TVMLP 82%). There was a significant difference (p < 0.05) in postoperative anal sphincter tone: 35%. The TVMLP group experienced a hypertonic anal sphincter, while none of the RSC group did. Regarding subjective improvement, the median PGI-I was 1 in both groups. At 12 months of follow-up, both groups exhibited a significant improvement in bowel symptoms. RSC and TVMLP successfully corrected multicompartment POP. RSC showed a greater improvement in the total Agachan-Wexner score and lower bowel symptoms.

Colonic Slow Transit in Patients with Dyssynergic Defecation and Effectiveness of Biofeedback Therapy

Background: Colonic transit is delayed in two-thirds of patients with dyssynergic defecation. As a result, it's possible that dyssynergic defecation and slow transit constipation are linked. There is a scarcity of research on the coexistence of dyssynergic defecation and slow transit constipation, as well as the efficacy of biofeedback therapy in this group of patients. &#x0D; &#x0D; Methods: The results of anorectal manometry and MR defecography were used to make the diagnosis of dyssynergic defecation. The colon transit time was measured with the help of 24 specially marked markers. All of the patients were given biofeedback therapy. &#x0D; &#x0D; Results: The average age of the 17 patients with dyssynergic defecation in the study was 45.6 years. The colon transit time was prolonged in seven patients (41.2%). In anorectal manometry, 7 patients (41.2%) had improved dyssynergic defecation after dyssynergic defecation. When the relationship between colon transit time and biofeedback therapy was investigated, it was discovered that normal colon transit time was found in 85.7 percent of those who benefited from biofeedback therapy, while slow transit constipation was found in 60% of those who did not. &#x0D; &#x0D; Conclusion: In patients with pre- biofeedback therapy and dyssynergic defecation, colon transit time should be evaluated, and it should be kept in mind that these patients may be resistant to treatment in the case of accompanying slow transit constipation.

MRI defecography revisited. At-rest pelvic floor measurements with and without rectal gel. Is there a difference?

The authors sought to test if there was a difference in key pelvic floor measurements obtained during MR defecography at-rest, i.e., H-line, M-line and anorectal angle (ARA), before and after rectal gel administration. The authors also sought to determine if any observed differences would affect the interpretation of the defecography studies. Institutional Review Board approval was obtained. An abdominal fellow retrospectively reviewed the images of all patients who underwent MRI defecography at our institution from January 2018 through June 2021. The H-line, M-line and ARA values were remeasured on T2-weighted sagittal images, with and without rectal gel for each patient. One hundred and eleven (111) studies were included in the analysis. 18% (N = 20) of patients satisfied the criterion for pelvic floor widening before gel administration based on H-line measurement. This increased to 27% (N = 30) after rectal gel (p = 0.08). 14.4% (N = 16) met the M-line measurement criterion for pelvic floor descent before gel administration. This increased to 38.7% after rectal gel (N = 43) (p < 0.001). 67.6% (N = 75) demonstrated an abnormal ARA prior to administration of rectal gel. This decreased to 58.6% (N = 65) after rectal gel administration (p = 0.07). The overall reporting discrepancies incurred by the presence or absence of rectal gel were 16.2%, 29.7% and 23.4% for H-line, M-line and ARA, respectively. The instillation of gel during MR defecography can cause significant changes to the observed pelvic floor measurements at-rest. This in turn can influence the interpretation of defecography studies.

A possible physiological mechanism of rectocele formation in women

BackgroundWe aimed to determine the anorectal physiological factors associated with rectocele formation.MethodsFemale patients (N = 32) with severe constipation, fecal incontinence, or suspicion of rectocele, who had undergone magnetic resonance defecography and anorectal function tests between 2015 and 2021, were retrospectively included for analysis. The anorectal function tests were used to measure pressure in the anorectum during defecation. Rectocele characteristics and pelvic floor anatomy were determined with magnetic resonance defecography. Constipation severity was determined with the Agachan score. Information regarding constipation-related symptoms was collected.ResultsMean rectocele size during defecation was 2.14 ± 0.88 cm. During defecation, the mean anal sphincter pressure just before defecation was 123.70 ± 67.37 mm Hg and was associated with rectocele size (P = 0.041). The Agachan constipation score was moderately correlated with anal sphincter pressure just before defecation (r = 0.465, P = 0.022), but not with rectocele size (r = 0.276, P = 0.191). During defecation, increased anal sphincter pressure just before defecation correlated moderately and positively with straining maneuvers (r = 0.539, P = 0.007) and defecation blockage (r = 0.532, P = 0.007). Rectocele size correlated moderately and positively with the distance between the pubococcygeal line and perineum (r = 0.446, P = 0.011).ConclusionIncreased anal sphincter pressure just before defecation is correlated with the rectocele size. Based on these results, it seems important to first treat the increased anal canal pressure before considering surgical rectocele repair to enhance patient outcomes.Graphical abstract

MR Defecography Findings Suggesting Anismus: Reliable or not Reliable?

MR Defecography Findings Suggesting Anismus: Reliable or not Reliable?

Evaluation of Pelvic Floor Dysfunction with Magnetic Resonance Defecography

Introduction: The aim of this study is to reveal MR defecography findings of pelvic floor failure and to highlight the significant points regarding acquiring and interpreting images. Materials and Methods: The patients who underwent MR defecography imaging in our department between 2013 and 2016 were retrospectively evaluated. Abnormalities of pelvic compartments were both investigated and graded. Axial diameter of the levator hiatus and iliococcygeus angle were measured at rest and during straining and the measurements were compared. H line, M line and ARA were measured at rest, during straining and defecation and the measurements were compared. Results: There was a statistically significant difference between rest and straining, rest and defecation, straining and defecation phases in terms of the length of M and H lines. Changes in the transverse diameter of levator hiatus and iliococcygeus angle between rest and straining phases were statistically significant. In the patients without spastic pelvic floor syndrome, there was a statistically significant difference between rest and straining, rest and defecation, straining and defecation phases in terms of ARA. In the patients with spastic pelvic floor syndrome, changes in ARA between rest and straining, rest and defecation phases were statistically significant. There was no statistically significant difference between straining and defecation phases in terms of ARA. Conclusion: MR defecography gives detailed information about pelvic compartment abnormalities in the patients with pelvic floor failure. While early images of defecation are more useful for the assessment of the posterior compartment, late phase images would allow more accurate definition of anterior and middle compartment abnormalities. Keywords: MR defecography, pelvic floor dysfunction, spastic pelvic floor syndrome

Agreement analysis of the magnetic resonance defecography and clinical examination findings in the evaluation of pelvic floor disorders

Agreement analysis of the magnetic resonance defecography and clinical examination findings in the evaluation of pelvic floor disorders

Rectal intussusception: Medical management and timing of the decision to operate

Rectal Intussusception (RI) occurs when the rectal wall telescopes distally without prolapse past the anal verge during defecation and occurs as the result of abnormal rectal wall biomechanics. Symptoms are variable though ¾ of patients with high grade intussusception report straining, incomplete emptying and the need for manual assistance during evacuation. The diagnosis of RI requires a comprehensive clinical history, physical exam and dynamic imaging of evacuation with MR or fluoroscopic defecography. Phenotypic grading is important as low-grade, non-obstructing RI may not significantly contribute to symptoms and outcomes following surgery in this group is poor. Initial management should focus on improving stool form and evacuatory dynamics in conjunction with biofeedback if there associated dyssynergia. Surgery should only be considered in those patients with high-grade intussusception and symptoms resistant to medical therapies after appropriate counselling regarding the risks and benefits of intervention.

PP35 Defecography (Evacuation Proctography) For The Evaluation Of Pelvic Floor Disorders: A Literature Review

IntroductionPelvic floor diseases (PFD) often affect the adult population, with approximately 50 percent of women aged 50 years and older suffering from PFD. The condition has complex symptoms that may lead to stress and a negative impact on the quality of life. The USA spends about USD 1 billion annually on inpatient costs as a result of more than 700,000 emergency department visits and 50,000 hospitalizations associated with PFD. Defecography is currently the most commonly used method of diagnostic imaging used to evaluate PFD. This technology is not available in the Republic of Kazakhstan, despite its high diagnostic value.MethodsIn order to assess the clinical effectiveness of defecography, we have conducted a literature search in the MEDLINE database. We selected articles with pairwise comparisons of defecography with other tests: anorectal manometry; balloon expulsion test; electromyography; magnetic resonance imaging (MRI); and, ultrasound.ResultsThe findings are primarily based on two meta-analysis (91 studies representing 10,768 cases). The results have been evaluated according to the detection frequency and omission of the following signs: cystocele, middle compartment descent, rectocele, intussusception, rectal prolapse, enterocele, and perineal descent. The literature review did not reveal significant difference in diagnostic value between MR defecography and defecography based on X-ray. However, the imaging endpoints (detection rate of structural and functional abnormalities) for defecography based on X-ray were significantly better than plain radiography.ConclusionsThe defecography is currently considered the gold standard and the most commonly used tool of diagnosis. The implementation does not require an expensive equipment purchase (MR defecography) and is reproducible on conventional X-ray equipment if the necessary inventory is available.

The Role of Magnetic Resonance Imaging Defecography in the Evaluation of Patients With Chronic Constipation

IntroductionPelvic floor dysfunction is one of the major causes of primary chronic constipation. Our study aims to assess utility of defecography using magnetic resonance imaging (MRI) in assessing pelvic floor dysfunction in these patients. MethodsMR defecography studies of 50 patients with chronic constipation done on 1.5 T/3 T MRI machines were analyzed retrospectively. Midline sagittal images were evaluated during rest, strain, and defecation phases. ResultsOf 50 patients, 62% had only compartment III involved, 8% had compartments II and III involved, 8% had compartments I and III involved, and 16% had all 3 compartments involved, the remaining 6% had no compartment involvement. Of the 21 patients with rectocele, anterior rectocele was more common than posterior. Anorectal angles were compared with the three grades of anorectal descent. Both moderate and severe grades of anorectal descent had an abnormal angle. ConclusionDynamic MR defecography helps identify pelvic floor dysfunction in patients with chronic constipation and helps design surgical repair to avoid recurrence.

S167 Comparison of High-Resolution Anorectal Manometry and Magnetic Resonance Defecography in Patients With Obstructive Defecation: Are Both Tests Necessary?

Introduction: Investigation of evacuation disorders is often pursued in patients with symptoms of obstructive defecation. High-resolution anorectal manometry (HR-ARM) is a simple, safe and widely available test to diagnose pelvic floor dysfunction. A more costly and less accessible test is magnetic resonance defecography (MRD). This study aims to qualify the added value of MRD in diagnosing pelvic floor disorders. Methods: HR-ARM and MRD performed in patients with a diagnosis of constipation between 1/1/2020 and 5/15/22 at Mayo Clinic were identified using Epic SlicerDicer. Univariate and multivariate analyses were used to compare findings on MRD in patients with and without abnormal HR-ARM. Results: Seventy-six consecutive patients (81.8% female, 94.8% white, age 19-82) who underwent both HR-ARM and MRD were included. The majority had evidence of dyssynergia on HR-ARM (n=49, 64.5%). Patients with dyssynergia on HR-ARM were significantly more likely to have prolonged balloon expulsion at both >60 and >30 seconds (p< 0.00001) and incomplete gel expulsion on MRD (p=0.00008) (Table). However, they were not more likely to have a clinically significant rectocele measuring >2cm (p=0.5093) or evidence of rectal prolapse (p=0.071). An increased number of vaginal deliveries was correlated with a higher likelihood of having a rectocele >2cm (r=0.24, p< 0.05). Conclusion: Anatomic findings on MRD were similar between patients with and without evidence of dyssynergia identified by HR-ARM. In this retrospective review, undergoing MRD in addition to HR-ARM does not appear to provide additional diagnostic information to guide therapeutic recommendations. Large prospective studies to evaluate the added value of MRD are needed. Table 1. - Findings on MRD and balloon expulsion test in patients with and without dyssynergia on HR-ARM Dyssynergia on HR-ARM No dyssynergia on HR-ARM P value n= 49 (64.5%) n = 27 (35.5%) Balloon Expulsion >60 sec 30 (61.2%) 0 (0.0%) p< 0.00001 Balloon Expulsion >30 sec 32 (65.3%) 2 (7.4%) p< 0.00001 < 50% gel expulsion on MR 26 (53.1%) 2 (7.4%) p=0.00008 Rectocele on MR 26 (53.1%) 22 (81.5%) p=0.0139 >2 cm Rectocele on MR 21 (42.9%) 16 (59.3%) p=0.5093 >3 cm Rectocele on MR 10 (20.4%) 9 (33.3%) p=0.2113 >4 cm Rectocele on MR 3 (6.1%) 3 (11.1%) p=0.4413 Rectal Prolapse 5 (10%) 7 (31.8%) p=0.071