Combined small and large bowel MR imaging in patients with Crohn?s disease: a feasibility study

Abstract

MRI of the small bowel is a new method for the assessment of inflammatory bowel diseases. However, inflammatory bowel disease can affect both the small and large bowel. Therefore, our goal was to assess the feasibility of displaying the small bowel and colon simultaneously by MR imaging. Eighteen patients with inflammatory bowel disease were studied. For small bowel distension, patients ingested a solution containing mannitol and locust bean gum. Furthermore, the colon was rectally filled with water. MR examinations were performed on a 1.5-T system. Before and after intravenous gadolinium administration, a T1w data set was collected. All patients underwent conventional colonoscopy as a standard of reference. The oral ingestion and the rectal application of water allowed an assessment of the small bowel and colon in all patients. By means of MRI (endoscopy), 19 (13) inflamed bowel segments in the colon and terminal ileum were detected. Furthermore, eight additional inflammatory lesions in the jejunum and proximal ileum that had not been endoscopically accessible were found by MRI. The simultaneous display of the small and large bowel by MRI is feasible. Major advantages of the proposed MR concept are related to its non-invasive character as well as to the potential to visualize parts of the small bowel that cannot be reached by endoscopy.

Role of spectral presaturation attenuated inversion‐recovery fat‐suppressed T2‐weighted MR imaging in active inflammatory bowel disease

“…Technical progress in MR imaging has formed the basis for a rapid evaluation of the GI tract with improved image quality (15)(16)(17). The benefits of 3D T1W gradient echo technique utilizing ultrashort TE and TR include minimization of artifacts from susceptibility effects that arise from bowel gas and improved spatial resolution.…”

Feasibility of evaluating Crohn's disease activity at 3.0 Tesla

“…However, differences in appraising these aspects contributed to the low interobserver values since, in addition to mesenteric hypervascularization, enhancement of bowel segments was rated differently by the two observers in 75 of 151 assessable segments. In the literature contrast enhancement has been described as one of the most important parameters that indicate active disease (9,27,29). However, in these studies quantitative measurements of percentage of contrast enhancement were obtained only from the most diseased segment of bowel, and were subsequently correlated with endoscopic findings.…”

“…However, before MRI can be considered an alternative for endoscopy in CD, it should be firmly established that in addition to detecting disease activity, MRI is capable of revealing both the severity and the exact location of disease. A few prospective studies have compared MRI with endoscopy regarding the severity of disease, but only the five most recent of these studies also analyzed the accuracy of MRI for localizing disease (27)(28)(29)(30)(31)(32)(33). The results of these studies were conflicting, and the reported sensitivities and specificities varied widely from approaching endoscopic accuracy to considerable over-or underestimation of disease.…”

Magnetic resonance cholangiopancreatography (MRCP) using new negative per-oral contrast agent based on superparamagnetic iron oxide nanoparticles for extrahepatic biliary duct visualization in liver cirrhosis

“…Ascites and bowel wall edema are displayed with high signal intensity in T2-weighted images and low in T1-weighted images, which is the same as for biphasic contrast agents. While signal intensity of positive contrast agent is high in T2-and T1-weighted images, on the other hand negative contrast agents are depicted as hypointense in T2-and T1-weighted images 7 . Therefore, application of negative contrast agents is the best choice for effective visualization of the above-mentioned problem parts of the abdominal cavity.…”

“…These SPIO per-oral contrast agents enable decrease in noise and motion artifacts related to bowel peristalsis and help us to improve the detection of intramural edema and extramural complications (necrosis, fat edema, mesenterial edema, abscess formation or fistulas) (ref. 7,8 ). Ascites and bowel wall edema are displayed with high signal intensity in T2-weighted images and low in T1-weighted images, which is the same as for biphasic contrast agents.…”