Experience of 4 years with open MR defecography: pictorial review of anorectal anatomy and disease.

Functional disorders of the pelvic floor are a common clinical problem. Diagnosis and treatment of these disorders, which frequently manifest with nonspecific symptoms such as constipation or incontinence, remain difficult. Fluoroscopic x-ray defecography has been shown to aid in detection of functional and morphologic abnormalities of the anorectal region. With the advent of open-configuration magnetic resonance (MR) imaging systems, MR defecography with the patient in a vertical position became possible. MR defecography permits analysis of the anorectal angle, the opening of the anal canal, the function of the puborectal muscle, and the descent of the pelvic floor during defecation. Good demonstration of the rectal wall permits visualization of intussusceptions and rectoceles. Excellent demonstration of the perirectal soft tissues allows assessment of spastic pelvic floor syndrome and descending perineum syndrome and visualization of enteroceles. MR defecography with an open-configuration magnet allows accurate assessment of anorectal morphology and function in relation to surrounding structures without exposing the patient to harmful ionizing radiation.     

Defecography by spiral computed tomography

PURPOSE: We investigated the possible role of helical CT defecography in pelvic floor disorders by comparing our results with those of conventional defecography. MATERIAL AND METHODS: Our series consisted of 90 patients, namely 62 women and 28 men, ranging in age 24-82 years. They were all submitted to conventional defecography, and 18 questionable cases were also studied with helical CT defecography. The conventional examination was performed during the 4 standard phases of resting, squeezing, Valsalva and straining; we used a remote-control unit. The parameters for helical CT defecography were: 5 mm beam collimation, pitch 2, 120 KV, 250 mAs and 18-20 degrees gantry inclination to acquire coronal images of the pelvic floor. The rectal ampulla was distended with a bolus of 300 mL nonionic iodinated contrast agent (dilution: 3 g/cc). The patient wore a napkin and was seated on the table, except for those who could not hold the position and were thus examined supine. Twenty-second helical scans were performed at rest and during evacuation; multiplanar reconstructions were obtained especially on the sagittal plane for comparison with conventional defecographic images. RESULTS: An unquestionable diagnosis could be made in all the 18 patients submitted to helical CT defecography. The diagnosis was in agreement with proctology results and added new information in all cases. Sixteen patients had constipation and 2 fecal incontinence--one from rectal prolapse and the other from a rectovaginal fistula. In this latter case helical CT defecography permitted to confirm the fistula and suggest its course. One patient had a previously undetected ovarian cancer metastatic to the anterior rectal wall. DISCUSSION AND CONCLUSIONS: Coronal helical CT defecography images permitted to map the perineal floor muscles, while sagittal reconstructions provided information on the ampulla and the levator ani. To conclude, helical CT defecography performed well in the study of pelvic floor disorders and can follow conventional defecography especially in questionable cases.     

MR排便造影在后盆腔障碍性疾病中的评估价值

后盆腔障碍疾病是以肛直肠解剖和功能异常为主的一类盆底功能障碍性疾病,伴有便秘、便失禁等临床症状。MR排便造影是一种动态MR成像方法,可对后盆腔结构形态和运动功能异常情况直观显示,能够鉴别后盆腔障碍性疾病的类型并认识其发病原因,如直肠膨出、肠疝、盆腔器官脱垂和直肠套叠、脱垂等,同时对便失禁早期的肛直肠形态学和功能学异常改变的诊断有重要提示价值。     

排粪X线造影在肠易激综合征诊断中的应用

为了解排粪X线造影在肠易激综合征患者中的应用价值，对12例便秘为主型、10例便秘和腹泻交替型、14例腹泻型肠易激综合征患者进行排粪X线造影。结果排粪造影阳性的例数为13例（36.11％），排便过程中的异常有多种，包括直肠前突、直肠粘膜脱垂、内脏下垂、会阴下降和盆底痉挛综合征等。说明排粪X线造影对肠易激综合征的诊断和治疗有一定的价值。     

结肠运输实验与排粪造影在诊断便秘中的临床应用(附110例分析)

目的　分析便秘的原因 ,并评价结肠运输实验与排粪造影对诊断便秘的价值。方法　对 110例临床诊断为便秘患者先做结肠运输实验 ,再做排粪造影。结果　结肠运输实验异常者 79例 ;排粪造影异常者 5 3例。综合分析结肠运输实验与排粪造影 ,诊断为结肠慢运输 40例 ,功能性出口梗阻 5 3例。结论　结肠运输实验与排粪造影联合应用 ,能够更加准确区分结肠慢运输与功能性出口梗阻所致的便秘 ,进一步明确功能性出口梗阻的病因 ,为临床治疗提供可靠的依据。     

Anorectal function in patients with defecation disorders and asymptomatic subjects: evaluation with defecography

A controlled radiologic study of anorectal function was performed with the use of defecography in 19 patients with constipation and 13 with incontinence. All patients were age and sex matched to control subjects who were referred for barium enema study and who had no defecation disorder. There were no statistically significant differences between either patient group and the control group in anorectal angle and excursion of the anorectal junction. In the 32 patients and 155 consecutive patients referred for defecography because of a variety of defecation disturbances, approximately twice as many rectal wall abnormalities were seen compared with findings in the control group. These findings included intussusception, rectal prolapse, rectocele, mucosal prolapse, spastic pelvic floor, descending perineum syndrome, and solitary rectal ulcer syndrome. In conclusion, the main role of defecography is to document rectal wall changes during defecation straining as possible causes of evacuation difficulties. Clinical symptoms should also be taken into account when treatment is contemplated.     

MR排粪造影在女性出口梗阻型便秘研究中的应用价值

目的 利用MR排粪造影研究女性出口梗阻型便秘的肛、直肠形态及功能性病变,同时对前、中盆腔联合性病变进行全面评价.方法 107例临床诊断为出口梗阻型便秘的女性患者,年龄20～84岁,平均55岁,进行MR排粪造影检查,使用自行设计高顺应性球囊模拟大便,分别测量静息、提肛及力排时盆底相关数据.结果 107例出口梗阻型便秘患者中,70例直肠前膨出(65.4%),为女性出口型便秘常见梗阻因素;85例(79.4%)患者为2种及2种以上的联合性病变,并发前、中盆腔病变,包括60例膀胱脱垂(56.1%)、59例子宫或阴道穹窿脱垂(55.1%)、54例会阴体下降(50.5%)、28例盆底疝(26.2%).结论 MR排粪造影不仅能准确评价出口梗阻型便秘女性患者的肛、直肠形态及功能性病变,同时能对前、中盆腔联合性病变进行全面评价.     

Assessment of chronic constipation: colon transit time versus defecography

OBJECTIVE: The aim of this study was to determine the value of radiological colon transit time (CTT) measurements in relation to defecography (DFG) in chronically constipated patients. MATERIALS AND METHODS: In 30 patients with chronic constipation, total and segmental CTT was determined using radiopaque markers. In all of these patients defecography (DFG) was obtained. The patients were divided into three groups: In group I, 11 patients were classified with idiopathic constipation based on low stool frequency, normal DFG, or absence of symptoms of abnormal defecation. In group II, ten patients with rectal intussusception were diagnosed by DFG. In group III, there were nine patients with rectal prolapse or spastic pelvic floor syndrome, based on results of DFG. RESULTS: Group I, idiopathic constipation (n = 11), showed increased total CTT (mean, 93 h) and segmental CTT (right colon, 33 h (36%), left colon, 31 h (33%), rectosigmoid, 29 h (31%)). In group II, intussusception (n = 10), patients had normal mean total CTT (54 h) and a relative decrease in rectosigmoid CTT (mean, 13 h (24%)). In group III (n =9), rectal prolapse (n = 5) or spastic pelvic floor syndrome (n = 4), patients showed elevated total (mean, 167 h) and rectosigmoidal CTT (mean, 95 h (57%)). Mean total CTT was significantly different between groups I and II and between groups II and III, and mean rectosigmoidal CTT was significantly different between all three groups (P < 0.05). CONCLUSION: The use of total and rectosigmoidal CTT helps to identify the underlying pathophysiology of chronic constipation. Furthermore CTT helps to identify patients, who may benefit from DFG.     

功能性便秘的病因与影像学诊断

目的：分析便秘的病因并评价结肠运输试验与排粪造影对诊断便秘的价值。方法：对１００例便秘患者作结肠运输试验及排粪造影。结果：结肠运输异常者４３例,出口梗阻者９６例,两种均存在者占４２例。４２例中,外科单纯纠正出口梗阻３１例,术后随访发现１５例症状无明显改善且复查排粪造影均表现正常。结论：由于出口梗阻与结肠无力常合并存在并相互作用,作者强调：结肠运输试验与排粪造影联合应用将有助于作出正确、全面的诊断和制定恰当的治疗方案。     

109例便秘患者的排粪造影分析

目的:通过便秘患者的排粪造影资料显示其肛管直肠形态及功能,寻找便秘原因.方法:109倒排粪造影,其中13例行结肠传输试验.结果:由于肛管直肠形态功能异常所致的排粪功能障碍者91例,其中女性病例占80.22%.而女性异常病例中又以直肠前突多见.排粪造影及结肠传输试验均异常者7例.外科单纯手术纠正者2例,术后随访造影表现正常.结论:排粪造影对于便秘患者病因分析及诊疗方案的制定有重要的意义.     

Imaging of the posterior pelvic floor

Disorders of the posterior pelvic floor are relatively common. The role of imaging in this field is increasing, especially in constipation, prolapse and anal incontinence, and currently imaging is an integral part of the investigation of these pelvic floor disorders. Evacuation proctography provides both structural and functional information for rectal voiding and prolapse. Dynamic MRI may be a valuable alternative as the pelvic floor muscles are visualised, and it is currently under evaluation. Endoluminal imaging is important in the management of anal incontinence. Both endosonography and endoanal MRI can be used for detection of anal sphincter defects. Endoanal MRI has the advantage of simultaneously evaluating external sphincter atrophy, which is an important predictive factor for the outcome of sphincter repair. Many aspects of constipation and prolapse remain incompletely understood and treatment is partly empirical; however, imaging has a central role in management to place patients into treatment-defined groups.     

直肠排粪造影在便秘患者病因诊断中的意义

目的评价直肠排粪造影在便秘原因诊断中的意义。方法56例临床怀疑由于肛肠疾病引起的便秘患者（女51例,男5例,年龄33～72岁,平均41岁）均在经肛门——直肠灌注对比剂为160％（W／V）的硫酸钡250mL后接受了直肠排粪造影。结果在56例便秘患者中,直肠前突见于42例。耻骨直肠肌肥厚4例,直肠前壁黏膜脱垂3例,直肠内套叠3例,乙状结肠疝2例,直肠息肉1例,以及经病理证实的直肠癌1例。结论直肠排粪造粪造影在便秘的病因学诊断中具有高度准确性。     

多层螺旋CT排便造影技术的初步临床应用

目的:探讨多层螺旋CT排便造影技术在盆底疾病检查方面的临床应用价值。方法:对本院48例功能性出口梗阻性便秘的患者进行仰卧位盆腔CT扫描及坐位螺旋CT排便造影检查,男12例,女36例,年龄32~83岁,患者直肠内注入200ml凡士林,在静坐、缩肛及排便3种状态下对盆腔进行冠状位扫描,采用多平面重建(MPR)对扫描图像进行后处理并测量数据。结果:48例患者中发现直肠前突31例、直肠内套叠3例、直肠前壁黏膜脱垂14例、直肠外脱垂1例、盆底痉挛综合征9例、会阴下降34例、内脏下垂4例、肠疝3例,子宫后倾2例、耻骨直肠肌综合征1例。结论:螺旋CT排便造影能准确显示直肠、肛管、盆底肌肉等盆底结构的器质性和功能性异常,是一种简单、无创、实用的检查方法。     

Imaging of constipation in infants and children

The aims of this review article are to present epidemiology, important definitions, clinical considerations, and etiologic and pathogenetic aspects of constipation in infants and children. Anatomy, physiology, and pathophysiology of the the anorectum are described. Special attention is given to the indications for diagnostic imaging, imaging techniques, and imaging findings with different causes of constipation. Other diagnostic modalities, such as anorectal manometry, electromyography, and biopsy techniques are briefly discussed. The central question as to whether diagnostic imaging is needed for the diagnostic workup of infants and children suffering from constipation can be answered affirmatively. Especially the combination of barium enema or defecography and anorectal manometry allows definition of those infants and children who do not need biopsy and surgery for Hirschsprung's disease. The special role of defecography in this context is underlined. Received 16 May 1997; Revision received 5 August 1997; Accepted 6 August 1997     

排粪造影对功能性出口梗阻便秘的诊断

目的　探讨排粪造影对功能性出口便秘的诊断价值。方法　对 5 0 0例功能性出口便秘患者进行排粪造影检查。女性 3 49例 ,男性 15 1例 ,年龄 14～ 78岁 ,平均 3 6.7岁。病史在 2个月～ 3 8年。主要临床症状 :排便困难、不适、腹痛、腹胀 ,排便时间延长 ,肛门坠胀及解不净 ,多数病人需长期服泻药及灌肠帮助排便。排粪造影是给病人灌入 40 0～ 60 0ml硫酸钡混悬液 ,病人侧坐在排便装置上 ,在X线电视下作动态观察、摄片。结果　通过对 5 0 0例患者排粪造影检查 ,发现有直肠前突 14 4例、直肠黏膜脱垂 75例、直肠内套叠 5 6例、盆底痉挛综合征 10 2例、耻骨直肠肌肥厚 65例、会阴下降 12 1例、正常 2 9例 ,以上症状多数由两种或两种以上同时出现。结论　排粪造影对功能性出口便秘的诊断具有重要价值。     

动态排粪造影对直肠前突的诊断价值

目的：探讨动态采集法排粪造影对直肠前突的诊断价值。方法：回顾性分析469例出口梗阻型便秘患者的排粪造影资料。常规排粪造影52例,动态排粪造影373例,同时行常规和动态排粪造影44例。比较两种方法对直肠前突的显示率。结果：动态法发现直肠前突310例（轻度67例、中度178例、重度65例）,占74．34％（310／417）;常规法发现直肠前突59例（轻度29例、中度25例、重度5例）,占61．46％（59／96）;两种方法差异存在显著性意义（P〈0．05）。结论：动态排粪造影能提高直肠前突的显示率,并能观察和记录直肠前突深度的动态变化,提高诊断准确率。     

MR defecography in patients with dyssynergic defecation: spectrum of imaging findings and diagnostic value

Objectives

We describe the spectrum of findings and the diagnostic value of MR defecography in patients referred with suspicion of dyssynergic defecation.

Methods

48 patients (34 females, 14 males; mean age 48 years) with constipation and clinically suspected dyssynergic defecation underwent MR defecography. Patients were divided into patients with dyssynergic defecation (n = 18) and constipated patients without dyssynergic defecation (control group, n = 30). MRIs were analysed for evacuation ability, time to initiate evacuation, time of evacuation, changes in the anorectal angle (ARA-change), presence of paradoxical sphincter contraction and presence of additional pelvic floor abnormalities. Sensitivity, specificity, positive and negative predictive values and accuracy for the diagnosis of dyssynergic defecation were calculated.

Results

The most frequent finding was impaired evacuation, which was seen in 100% of patients with dyssynergic defecation and in 83% of the control group, yielding a sensitivity for MR defecography for the diagnosis of dyssynergic defecation of 100% (95% confidence interval (CI) 97–100%), but a specificity of only 23% (95% CI 7–40%). A lower sensitivity (50%; 95% CI 24–76%) and a high specificity (97%; 95% CI 89–100%) were seen with abnormal ARA-change. The sensitivity of paradoxical sphincter contraction was relatively high (83%; 95% CI 63–100%). A combined analysis of abnormal ARA-change and paradoxical sphincter contraction allowed for the detection of 94% (95% CI 81–100%) of the patients with dyssynergic defecation.

Conclusion

MR defecography detects functional and structural abnormal findings in patients with clinically suspected dyssynergic defecation. Impaired evacuation is seen in patients with functional constipation owing to other pelvic floor abnormalities than dyssynergic defecation.Dyssynergic defecation, which produces functional outlet obstruction during defecation, is one of the causes of chronic constipation. Dyssynergic defecation is a functional disorder characterised by either paradoxical contraction, an inability to relax the anal sphincter and/or puborectalis muscle, or impaired abdominal and rectal pushing forces. In the literature, many other terms such as anismus [1], dyskinetic puborectalis muscle [2], non-relaxing puborectalis syndrome [3], spastic pelvic floor syndrome [4, 5] and pelvic floor dyssynergia [6] have been used. An expert group (Rome III) [7] recently proposed the term “dyssynergic defecation” to appropriately describe the failure of co-ordination or dyssynergia of the abdominal and pelvic floor muscles involved in defecation. Different physiological tests can be used to investigate this functional disorder, including the balloon expulsion test, electromyography (EMG) of the puborectalis muscle and anorectal manometry. Defecography can be performed to rule out structural rectal abnormalities and provide an estimate of the degree of rectal emptying. As false-positive and false-negative results are common with these different tests, none can be used by itself as a gold standard for identifying patients with dyssynergic defecation.Most authorities recommend using a combination of diagnostic tests and clinical history. The Rome III expert group defined the criteria for the diagnosis of dyssynergic defecation based on clinical history, anorectal manometry, balloon expulsion test, EMG and conventional defecography (evacuation proctography) [7]. Functional imaging with conventional defecography is considered to be a useful adjunct in establishing the diagnosis of dyssynergic defecation. Delayed initiation of evacuation and impaired evacuation in particular, as seen on conventional defecography, are highly predicitive for the presence of dyssynergic defecation [8, 9]. Different structural imaging findings in conventional defecography have been described in patients with dyssynergic defecation; however, the usefulness of these findings is discussed controversially [8, 10, 11].The experience with MR defecography, which has shown to be a valuable alternative to evacuation proctography [12–15], is limited in dyssynergic defecation patients. There is only one study which has focused on the MR defecography findings in a study setting in patients with dyssynergic defecation [16]. Hence, the purpose of this study was to describe the spectrum of findings in MR defecography in patients referred with the suspicion of dyssynergic defecation and to assess the value of MR defecography in establishing this diagnosis. For the latter, the patients with dyssynergic defecation were compared with a group of constipated patients without dyssynergic defecation.     

Dynamic MR defecography with an open-configuration, low-field, tilting MR system in patients with pelvic floor disorders

Purpose

This study was undertaken to explore the capabilities of an open-configuration, low-field, tilting, magnetic resonance (MR) system for investigating pelvic floor disorders and to compare the results obtained with the patient in the semiorthostatic and supine positions.

Materials and methods

Eighteen female patients with a diagnosis of pelvic floor disorder (physical examination and conventional defecography) underwent dynamic MR defecography (MRD) with a 0.25-T tilting MR system (G-scan, Esaote). Images were obtained after administration of contrast agent into the rectum, bladder and vagina in both the orthostatic and supine positions. Three-dimensional T2-weighted hybrid contrast-enhanced (HYCE) sequences and dynamic T1-weighted gradient echo (GE) sequences were acquired at rest, during maximal contraction of the anal sphincter, straining and defecation.

Results

Good image quality was obtained in 15/18 patients; three presented severe artefacts due to motion, and three had incontinence, which hampered the functional studies. Better anatomical detail was obtained with MRD compared with conventional defecography. Three prolapses were observed in the semiorthostatic position only, and seven were found to be more severe in the orthostatic than in the supine position.

Conclusions

Dynamic MRD with an open-configuration, low-field, tilting MR system is a feasible and promising tool for studying the pelvic floor. Larger series are necessary to assess its real diagnostic value.     

功能性出口梗阻性便秘的影像学研究进展

出口梗阻性便秘（OOC）是一种女性患者的常见病,尤其多见于经产妇,早期而准确的诊断是治疗的关键。对于该疾病有多种影像学诊断方法,包括钡灌肠、结肠传输功能试验、直肠排粪造影、气钡双对比灌肠联合直肠排粪造影、仿真直肠排粪造影等。本文综述了各种影像学检查的优缺点及应用进展。