Magnetic Resonance Enteroclysis Research Articles

The “star-sign” in magnetic resonance enteroclysis: A characteristic finding of internal fistulae in Crohn's disease

Clinical symptoms in patients with Crohn's disease (CD) and internal fistulae (IFs) may be unspecific [1] and require further diagnostic investigations such as laboratory findings, endoscopic and i...

Comprehensive Magnetic Resonance Imaging of the Small and Large Bowel Using Intraluminal Dual Contrast Technique With Iron Oxide Solution and Water in Magnetic Resonance Enteroclysis

The objective of this study was to improve delineation of small and large bowel (SB, LB) anatomy and pathology with postoperative or complex multisegmental inflammatory changes using dual-contrast-technique (DCT) for magnetic resonance enteroclysis (MRE) with luminal contrast media of opposed signal characteristics. Sixty patients underwent MRE with iron oxide-based negative contrast in the SB. Thirty patients received additional rectal instillation of water for positive contrast (DCT). Two observers evaluated the degree of distention and the ease of identification of bowel anatomy and pathologies (none n=22, stenosis n=16, abscess n=4, fistulae n=5, postoperative changes and adhesions n=13) using a 4-point scale. Mann-Whitney U-test and kappa statistics were applied. LB and the terminal ileum were significantly better distended and identified with DCT (P<or=0.0001; P=0.034). Interobserver agreement improved with DCT for all pathologies except for "prestenotic dilatation." Comprehensive MR imaging of SB and LB with DCT improves the identification of modified anatomy and most pathologies in inflammatory and postsurgical bowel.

Conventional enteroclysis with complementary MR enteroclysis: a combination of small bowel imaging

Conventional enteroclysis with complementary MR enteroclysis: a combination of small bowel imaging

Magnetic Resonance Enteroclysis

MR enteroclysis (MRE) is an emerging technique for the evaluation of small intestinal diseases. Administration of an iso-osmotic water solution through a nasojejunal catheter can guarantee adequate luminal distention, and in combination with ultrafast sequences, such as single shot TSE, true FISP, HASTE and 3D FLASH, results in excellent anatomic demonstration of the small intestine. MR fluoroscopy can be performed during MRE examination to monitor the filling process and might be useful in studying low-grade stenosis or motility related disorders. MRE is a very promising technique for the detection and characterization of involved small bowel segments in patients with Crohn's disease while its diagnostic performance in disclosing lumen narrowing and extramural manifestations and complications of the disease is outstanding. Initial experience shows that MRE is very efficient in the diagnosis of small bowel tumors and can be used in the evaluation of small bowel obstruction.

Life-Threatening Chronic Enteritis Due to Colonization of the Small Bowel With Stenotrophomonas maltophilia

Life-Threatening Chronic Enteritis Due to Colonization of the Small Bowel With Stenotrophomonas maltophilia

Life-Threatening Chronic Enteritis Due to Colonization of the Small Bowel With

Life-Threatening Chronic Enteritis Due to Colonization of the Small Bowel With

A combination of small bowel imaging methods: conventional enteroclysis with complementary magnetic resonance enteroclysis

The aim of this prospective study was to evaluate the overall findings of conventional enteroclysis (CE) with complementary magnetic resonance enteroclysis (MRE) in small bowel disease. The study included 32 patients referred from various clinical departments, with known or suspected small bowel disease and abnormalities on CE. Immediately after CE, true fast imaging with steady-state precession (true FISP), and unenhanced and gadolinium-enhanced T1-weighted fast low-angle shot (FLASH) sequences with fat saturation were obtained. Mucosal, mural and luminal changes of the small bowel were evaluated by each technique. In addition, bowel wall thickening, bowel wall enhancement and perienteric changes were assessed by MRE. The radiological findings obtained were evaluated together as a combination, and the role of MRE in the determination of the activity and complications of the small bowel disease was assessed. Radiological findings were correlated with clinical evaluation and follow-up in all cases, including endoscopy in 14 cases and surgery in 5 cases. MRE provided important supplementary mural and extramural information, including degree of pathological wall thickness, mural enhancement pattern associated with disease activity, perivisceral collection, abscess formation, mesenteric fibrofatty proliferation, lymphadenopathy and increase in perienteric vascularity. Short strictures were not revealed on MRE; however, for patients with a history of abdominal malignancy, MRE helped characterize the level of any obstruction and the extent of the disease. We recommend MRE for patients who have findings of advanced inflammatory bowel disease or neoplasm on CE examination. The combination of these two techniques can provide important information on the degree and extent of the disorder.

MRI in Crohn's disease

Technological developments have extended the role of MRI in the evaluation of the gastrointestinal tract. The potential of MRI to evaluate disease activity in Crohn's disease has been investigated extensively, as MRI has intrinsic advantages over other techniques, including noninvasiveness and the absence of ionizing radiation. For perianal fistulizing disease MRI has become a mainstay in evaluation of disease, as localization and extent of disease can be very well appreciated using both T2-weighted and T1-weighted sequences, fat suppression, and intravenous contrast medium. Imaging of the small bowel and colon in Crohn's disease is more complicated due to bowel peristalsis and respiratory movement. However, using fast breathhold sequences and intravenous spasmolytic medication, images of good diagnostic quality can be acquired. To obtain sufficiently distended bowel, which in our estimation is a prerequisite for evaluation of the bowel, MR enteroclysis can be performed. However, applicability of different oral contrast media has been studied, as a noninvasive method for bowel distension would be preferable. Abdominal MRI is a valuable imaging technique for evaluation of luminal, transmural, and extraintestinal manifestations of Crohn's disease as degree of disease activity, presence of luminal pathology (e.g., stenoses), and extraintestinal manifestations of disease (e.g., abscesses, fistulas) can be accurately assessed.

Comparison of capsule endoscopy and magnetic resonance (MR) enteroclysis in suspected small bowel disease

Small bowel MR enteroclysis and wireless capsule endoscopy (WCE) are new diagnostic tools for the investigation of the small bowel. The aim of this study was to compare the diagnostic yield of WCE with MR enteroclysis in the detection of small bowel pathologies. A total of 36 patients were included in the study. Indications for imaging of the small bowel were proven or suspected small bowel Crohn's disease (CD; n=18), obscure gastrointestinal (GI) bleeding (n=14) and tumour surveillance (n=4). In patients with Crohn's disease WCE detected significantly more inflammatory lesions in the first two segments of the small bowel compared with MR enteroclysis (12 patients vs. 1 patient, p=0.016). In 5 out of 14 (36%) patients with GI bleeding, angiodysplasia was detected as a possible bleeding source. Three of these patients had active bleeding sites detected by WCE. One patient had scattered inflammation of the mucosa. MR enteroclysis did not reveal any intestinal abnormalities in this patient group. MR enteroclysis provided extraintestinal pathologies in 10 out of 36 (28%) patients. In patients with Crohn's disease WCE revealed significantly more inflammatory lesions in the proximal and middle part of the small bowel in comparison to MR enteroclysis, whereas in patients with obscure GI bleeding WCE was superior to MR enteroclysis.

Dark Lumen Magnetic Resonance Enteroclysis in Combination With Mri Colonography for Whole Bowel Assessment in Patients With Crohnʼs Disease: First Clinical Experience

Magnetic resonance enteroclysis (MRE) is a recently introduced imaging technique that assesses the small bowel with similar sensitivity and specificity as the fluoroscopically performed conventional enteroclysis. Magnetic resonance imaging colonography (MRC) seems to be a promising technique for polyp assessment in the colon. In this feasibility study, we evaluated the combination of small bowel MRI with unprepared MRC as an integrative diagnostic approach of the whole bowel in patients with Crohn's disease. Thirty patients with known Crohn's disease were prospectively examined. No particular colonic preparation was applied. Applying the dark lumen technique in all patients, MRE and MRC were performed within 1 session using an integrative examination protocol. T2-weighted and contrast-enhanced T1-weighted sequences were acquired. Inflammation assessment (grades 0 to 2) of the colon was compared with conventional colonoscopy in 29 patient and with surgery in 1 patient. The entire colon was graded fair to good distended in all patients. In 11 of 210 evaluated colonic segments, feces hindered an adequate intraluminal bowel assessment. Twenty-three of 30 patients had complete colonoscopy as the gold standard. In 7 patients, complete colonoscopy could not be performed because of an inflamed stenosis. Correct grading of colonic inflammation was performed with 55.1% sensitivity and 98.2% specificity in all segments. Considering only more extensive inflammation (grade 2), the sensitivity of MRC increased to 70.2% with a specificity of 99.2%. The combination of MRE and MRC could improve the diagnostic value of abdominal MRI evaluation in patients with Crohn's disease. However, MRC can not replace conventional colonoscopy in subtle inflammation assessment.

Inflammatory Bowel Disease

This review summarizes important publications that have appeared during the last year dealing with imaging techniques and endoscopy, as well as the management of low-grade dysplasia and stenosis in inflammatory bowel disease. Magnetic resonance enteroclysis and capsule endoscopy are currently emerging as new imaging techniques for the small bowel in Crohn's disease. While magnetic resonance enteroclysis is, at least in Europe, increasingly being used as a reference method, the value of capsule endoscopy for the management of inflammatory bowel disease is still being evaluated. Chromoendoscopy is being studied in patients with long-lasting ulcerative colitis and may be a promising and sensitive technique for the diagnosis of dysplasia. However, there are conflicting data regarding the appropriate management when low-grade dysplasia is diagnosed in patients with ulcerative colitis. Endoscopic dilation can often be successfully carried out in cases of intestinal stenosis. The results of long-term follow-up studies indicate that several dilation procedures are often necessary and that a relatively high percentage of patients still have to undergo surgery.

Mr enteroclysis using iron oxide particles (ferristene) as an endoluminal contrast agent: An open phase III trial

To evaluate efficacy and safety of a superparamagnetic iron oxide contrast agent (ferristene) as an endoluminal contrast medium for magnetic resonance (MR) enteroclysis in a phase III trial. Twenty-three patients with history of known or suspected small bowel Crohn's disease underwent MR imaging of the abdomen at 0.5 T unit. The imaging protocol included two phases: the first one without administration of any contrast agent and the second one, where the small bowel was filled by enteroclysis with 800 ml of the luminal iron oxide contrast medium and Gd-DTPA (0.1 mmol/Kg) was administered intravenously. Axial Spin-Echo (SE) T1-weighted (T1w), proton-density and T2w images, sagittal and coronal SE T1w and Short TI Inversion Recovery (STIR) sequences were subsequently obtained. Three investigators blindly evaluated images to determine small bowel distribution of ferristene, presence of artifacts, delineation of bowel lesion/wall and the diagnostic value of ferristene combined with gadolinium. Pre- and postcontrast signal intensity measurements of bowel lesion/wall, bowel lumen and background noise were also calculated. Three patients withdrew before the procedure, therefore 20 patients were effectively included in the study. No significant difference between the three investigators' evaluations of the improvement of the diagnostic information was found (percentage of improvement of 90% with 95% confidence limits of 68% and 99%). A statistically significant difference between the first and third investigators was found for grading of quality of delineation of bowel lesion/wall. Signal intensity measures showed a significant increase of the bowel lesion/wall and background noise/lesion for the SE T1w images. No serious adverse event was reported in our series. MR enteroclysis using ferristene as an endoluminal contrast agent appears to be a safe and efficient procedure for the study of the small bowel.

Abdominal MRI after enteroclysis or with oral contrast in patients with suspected or proven Crohn’s disease

Background & Aims: Diagnostic results of magnetic resonance (MR) enteroclysis correlate highly with those from conventional enteroclysis; nevertheless, intubation of the patient and positioning of an intestinal tube is still necessary for the examination, which is often remembered as the most embarrassing part of the examination by the patient. A more comfortable and highly sensitive examination of the small bowel therefore would increase patient acceptance for recurring examinations, which are often necessary, for example, in patients with Crohn’s disease. This study evaluates the diagnostic efficacy of abdominal MR imaging (MRI) of the small bowel after drinking contrast agent only compared with conventional enteroclysis and abdominal MRI performed after enteroclysis in patients with suspected or proven Crohn’s disease. Methods: Twenty-one patients with Crohn’s disease referred for conventional enteroclysis underwent abdominal MRI after enteroclysis. Additionally, 1 to 3 days before or after these examinations, abdominal MRI was performed using only orally administered contrast. All MRI examinations were performed using a 1.5T scanner. Results: All pathological findings on conventional enteroclysis were shown correctly with MRI after enteroclysis and MRI after oral contrast only. Additional information by MRI was obtained in 6 of 21 patients. No statistically significant differences were found in assessing the diagnostic efficacy of the 3 examinations. Conclusions: Abdominal MRI with oral contrast only can be used as a diagnostic tool for evaluation of the small bowel in patients with Crohn’s disease and has the potential to replace conventional enteroclysis as follow-up.

The value of MR enteroclysis with air infusion in the diagnosis of small bowel disease

目的 探讨磁共振注气小肠灌肠检查(MR enteroclysis)对小肠疾病的诊断价值.方法16例临床怀疑小肠非急性炎症性疾病且无肠梗阻的患者接受了MR注气小肠灌肠检查.其中男12例,女4例,年龄最大75岁,最小17岁,症状主要为腹痛10例,血便或黑便4例,腹泻2例,病程最长7年,最短1周.MR检查前先将小肠导管经鼻插入十二指肠远端,经导管注入空气1000 ml左右以扩张小肠,然后经静脉注入山莨菪碱 20 mg以抑制肠蠕动,采用37.2%的钆喷替酸葡甲胺(Gd-DTPA)12 ml行直接增强扫描,扫描序列包括带脂肪抑制的冠状面和横断面T1WI SE序列和快速扰相位梯度回波( fast spoiled gradient echo, FSPGR)序列.将MRI诊断结果与手术、病理结果或临床诊断对照,以评价MRI诊断的敏感性和特异性.结果正常小肠5例,Crohn病6例,回肠间质瘤2例,淋巴瘤、肠结核和易激综合征各1例.MR注气小肠灌肠的正常小肠在T1WI肠腔为无信号,肠壁在肠腔气体和周围充气肠管的衬托下显示为中等信号,肠壁厚度为1～3 mm,肠腔直径为17～28 mm;Crohn病表现为节段性肠壁增厚,强化增加,肠腔狭窄,肠管外可形成炎性肿块或瘘管;肠结核侵及回肠末段、盲肠及升结肠近端,肠壁明显增厚,强化增加,盲、升结肠近端短缩.间质瘤为等T1、长T2信号的圆形肿块,强化显著.1例术后复发的回肠淋巴瘤表现为肠壁增厚,强化增加,但无肠腔狭窄,1例易激综合征为小肠功能紊乱,其形态及信号正常.MR注气小肠灌肠将1例以肿块为突出表现的Crohn病误诊为淋巴瘤,1例易激综合征诊断为正常小肠,其余14例结合临床资料,MRI均做出正确诊断.MRI对小肠器质性病变诊断的敏感性为100%,特异性为83%.结论 MR注气小肠灌肠是诊断小肠器质性疾病,尤其是Crohn病和肿瘤的敏感的检查方法,能清楚显示小肠Crohn病的病变范围和肠管外并发症。

Crohn disease: magnetic resonance enteroclysis.

Crohn disease: magnetic resonance enteroclysis.

Capsule endoscopy for small bowel surveillance in hereditary intestinal polyposis and non-polyposis syndromes.

Capsule endoscopy (CE) is a novel method used to assess endoscopically the entire small bowel. We prospectively examined 35 patients with hereditary colorectal cancer syndromes-21 with familial adenomatous polyposis (FAP), 10 with Peutz-Jeghers Syndrome (PJS), two with familial juvenile polyposis (FJP), and two with hereditary nonpolyposis colorectal cancer (HNPCC)- who have an increased risk for small bowel carcinomas (SBC) by using CE. We found that in FAP patients, CE provided little significant additional information when compared with intestinoscopy. Moreover, assessment of the papilla of Vater was not possible, and polyps around the papilla of Vater can be missed by CE. Hence, side-viewing duodenoscopy with histology remains the most important surveillance examination for FAP. However, in PJS, CE results correlated well with established procedures such as push enteroscopy, enteroclysis, magnetic resonance enteroclysis, and surgery. CE can disclose additional polyps in the distal small bowel, which is of high clinical importance for the management of PJS and FJP patients to prevent benign complications and cancer. Our data suggest that CE can be recommended as a first-line surveillance technique in PJS and FJP. Regarding HNPCC, diagnostic algorithms have to be defined to enable early detection of SBC in high-risk patients.

Technical challenges and clinical applications of magnetic resonance enteroclysis.

With the advent of gradient systems the image quality of ultrafast pulse sequences, i.e., half Fourier acquisition single shot turbo spin echo (HASTE), true fast imaging with steady-state processing and fast low angle shot (FLASH), improved substantially and clinical applications including small bowel imaging became feasible. Within this context, magnetic resonance enteroclysis was developed as a comprehensive examination of the small bowel, providing luminal, transmural, and exoenteric diagnostic information of small bowel abnormalities. Clinical applications of magnetic resonance enteroclysis include diagnostic evaluation and follow-up of patients with inflammatory or neoplastic diseases and small bowel obstruction.

Optimization of a contrast medium suitable for conventional enteroclysis, MR enteroclysis, and virtual MR enteroscopy.

The purpose of the current study was to optimize a gadolinium-barium sulfate solution suitable for performing conventional and MR enteroclysis examinations in the same session. Eighteen vials of 20% barium sulfate and various gadolinium concentrations (lower 0 ml/lt, higher 45 ml/lt) were prepared and placed in the magnet. The imaging protocol was consisted of the following sequences: true FISP, HASTE with fat saturation and 3d FLASH with fat saturation in various flip angles. Ten patients underwent conventional enteroclysis with 1.2 lt of 20% barium sulfate enema and 18 ml of gadolinium. MR enteroclysis was performed afterwards using true FISP, fat suppressed 3d FLASH and fat suppressed HASTE sequences. The lowest gadolinium concentration in the barium sulfate solution generating low intraluminal signal on HASTE and high intraluminal signal on true FISP and 3d FLASH sequences was 15 ml/lt. The presence of gadolinium did not influence the lumen opacification in conventional enteroclysis examination. In all patients the proposed contrast medium acted as positive in 3d FLASH (T1w), true FISP (T2/T1 w) and as a negative in HASTE (T2w). Bowel wall conspicuity, lumen opacification and distention were ranked as very good to excellent on MR enteroclysis images while artifacts level did not downgraded the overall image quality. High quality virtual MR endoluminal views of the small bowel, based on 3d FLASH images, were obtained in all cases. A 20% barium sulfate enema with 15 ml/lt gadolinium is appropriate for conventional and MR enteroclysis examinations.

MR enteroclysis: technical considerations and clinical applications

Magnetic resonance enteroclysis (MRE) is an emerging technique for the evaluation of small bowel abnormalities. Adequate luminal distention, achieved by the administration of iso-osmotic water solution through a nasojejunal catheter, in combination with ultrafast sequences, such as single-shot turbo spin echo, true fast imaging with steady precession, half-Fourier acquired single-shot turbo spin echo, and 3D fast low-angle shot, results in excellent anatomic demonstration of the small bowel. Magnetic resonance fluoroscopy can be performed during MRE examination and might be useful in studying low-grade stenosis or motility-related disorders. Magnetic resonance enteroclysis is very promising in detecting the number and extent of involved small bowel segments in patients with Crohn's disease, and in disclosing lumen narrowing and extramural manifestations and complications of the disease. Initial experience shows that MRE is very efficient in the diagnosis of small bowel tumors and can be used in the evaluation of small bowel obstruction.

MR enteroclysis imaging of Crohn disease.

Magnetic resonance (MR) enteroclysis imaging is emerging as a technique for evaluation of the small bowel in patients with Crohn disease. Administration of 1.5-2 L of isosmotic water solution through a nasojejunal catheter ensures distention of the bowel and facilitates identification of wall abnormalities. True fast imaging with steady-state precession (FISP), half-Fourier acquisition single-shot turbo spin-echo (HASTE), and postgadolinium T1-weighted three-dimensional fast low-angle shot sequences can be employed in a comprehensive and integrated MR enteroclysis examination protocol to overcome specific disadvantages of each of the sequences involved. Superficial abnormalities that are ideally delineated with conventional enteroclysis are not consistently depicted with MR enteroclysis. The characteristic transmural abnormalities of Crohn disease such as bowel wall thickening, linear ulcers, and cobblestoning are accurately shown with MR enteroclysis imaging, especially with the true FISP sequence. MR enteroclysis is comparable to conventional enteroclysis in the detection of the number and extent of involved small bowel segments and in the disclosure of luminal narrowing or prestenotic intestinal dilatation. The clinical utility of MR enteroclysis in Crohn disease has not been fully established. At present, the method may be used for follow-up studies of known disease, estimation of disease activity, and determination of the extramucosal extent and spread of the disease process.