Crohn's Disease Imaging: A Review

Crohn's disease is a chronic granulomatous inflammatory disease of the gastrointestinal tract, which can involve almost any segment from the mouth to the anus. Typically, Crohn's lesions attain segmental and asynchronous distribution with varying levels of seriousness, although the sites most frequently involved are the terminal ileum and the proximal colon. A single gold standard for the diagnosis of CD is not available and the diagnosis of CD is confirmed by clinical evaluation and a combination of endoscopic, histological, radiological, and/or biochemical investigations. In recent years, many studies have been performed to investigate the diagnostic potential of less invasive and more patient-friendly imaging modalities in the evaluation of Crohn's disease including conventional enteroclysis, ultrasonography, color-power Doppler, contrast-enhanced ultrasonography, multidetector CT enteroclysis, MRI enteroclysis, and 99mTc-HMPAO-labeled leukocyte scintigraphy. The potential diagnostic role of each imaging modality has to be considered in different clinical degrees of the disease, because there is no single imaging technique that allows a correct diagnosis and may be performed with similar results in every institution. The aim of this paper is to point out the advantages and limitations of the various imaging techniques in patients with suspected or proven Crohn's disease

Radiological and imaging features

Imaging offers several modalities in the assessment of pediatric inflammatory bowel disease. Thesemodalities are represented by conventional barium studies, sonography and cross-sectional imaging methods such as computed tomography (CT) and magnetic resonance imaging (MRI). We brieflyreview the technical features of these techniques and our findings in cases with pediatric Crohn'sdisease, ulcerative colitis and indeterminate colitis. Choice of the appropriate imaging technique depends on the clinical setting. Thanks to technical developments, sonogaphy, CT and MRInow play an emerging role in the diagnostic process in children as well as in the adult population.Nevertheless, conventional barium studies still play a role in the assessment of the gut since they arewidely available, easily performed and clearly depict superficial changes in the mucosal layer of thegut. Cross-sectional imaging like sonography and MRI can easily depict mural thickening of Crohn'sdisease and offers a noninvasive and ionizing-free imaging modality for assessment of the smallbowel. Especially MRI with adequate intestinal distention can provide us with excellent informationon the presence, extension and activity of Crohn's disease. Nevertheless, MRI requires patient compliance that is not always easy in children. Copyright © 2009 S. Karger AG, Basel

Bowel intussusceptions in adults: the role of imaging

Intestinal intussusception in adults is a rare condition, accounting for about 0.003-0.02 % of all hospital admissions. This condition in adults represents only 5 % of all cases of intussusceptions and is different from paediatric intussusception, which is usually idiopathic. In contrast, almost 90 % of cases in adults are secondary to various pathologies that serve as a lead point, such as polyps, Meckel's diverticulum, colonic diverticulum, or malignant or benign neoplasm. The aim of the present study was to assess the capabilities of multislice computed tomography (MSCT) in the diagnosis and correct characterisation of intussusception, especially in distinguishing between intussusceptions with a lead point and those without. Indeed, although the MSCT findings that help to differentiate between lead point and non-lead point intussusceptions have not been well studied, abdominal MSCT remains the most sensitive radiological tool to confirm bowel intussusceptions. Moreover, differentiating intussusceptions with a lead point condition from those without is crucial for directing the patient towards the most appropriate treatment, avoiding surgery when not necessary

Ischemic Bowel Disease

Gastrointestinal tract ischemia and infarction comprises different clinical syndromes characterized by inadequate blood perfusion to the bowel. The age of onset depends on gender and the etiology of the ischemia, even if the majority of patients are over age 60. These disorders have been increasing over the past decade and constitute approximately 1–2 % of admissions for abdominal pain in the USA and 3.7 % of surgical intervention for acute abdomen in Italy. The increase in incidence can be attributed to various factors, including increased clinical awareness, aging population, and improvement in diagnostic imaging techniques. The mortality rate is very high, between 50 and 90 %, hence, timely diagnosis is essential to improve the outcome. The pathogenesis and symptoms of intestinal ischemia are extremely variable, and the diagnosis largely depends on clinical suspicion. A recent classification of ischemic bowel diseases, developed by the American Gastroenterological Association (AGA) in 2000, defines three clinical categories: acute mesenteric ischemia (AMI), chronic mesenteric ischemia (CMI) also known as intestinal angina, and ischemic colitis (IC)

Bowel Obstruction

Bowel obstruction is a common but difficult clinical problem in terms of appropriate and timely management. In clinical practice, radiologists play a key role not only in making the diagnosis but also in guiding physicians toward appropriate and timely management of many indeterminate cases and situations. In this chapter, small and large bowel obstruction is illustrated, from pathophysiology to imaging, emphasizing the role of multidetector computed tomography (MDCT) in the diagnosis and management of bowel obstruction. Furthermore, the place of allied imaging modalities such as plain film and ultrasonography is comprehensively illustrated

Acute arterial mesenteric ischemia and reperfusion: macroscopic and MRI findings, preliminary report

AIM: To explore the physiopathology and magnetic resonance imaging (MRI) findings in an animal model of acute arterial mesenteric ischemia (AAMI) with and without reperfusion.METHODS: In this study, 8 adult Sprague-Dawley rats underwent superior mesenteric artery (SMA) ligation and were then randomly divided in two groups of 4. In group., the ischemia was maintained for 8 h. In group., 1-h after SMA occlusion, the ligation was removed by cutting the thread fixed on the back of the animal, and reperfusion was monitored for 8 h. MRI was performed using a 7-T system.RESULTS: We found that, in the case of AAMI without reperfusion, spastic reflex ileus, hypotonic reflex ileus, free abdominal fluid and bowel wall thinning are present from the second hour, and bowel wall hyperintensity in T2-W sequences are present from the fourth hour. The reperfusion model shows the presence of early bowel wall hyperintensity in T2-W sequences after 1 h and bowel wall thickening from the second hour.CONCLUSION: Our study has shown that MRI can assess pathological changes that occur in the small bowel and distinguish between the presence and absence of reperfusion after induced acute arterial ischemia. (C) 2013 Baishideng. All rights reserved