Capsule endoscopy for small-bowel evaluation in Crohn's disease

Capsule endoscopy (CE) is increasingly accepted as a technique for small-bowel evaluation with a high diagnostic yield. Although the role of CE in evaluation of GI bleeding is now well established, its proper place in the evaluation of other small-bowel disorders, particularly Crohn's disease (CD), is less certain. The diagnosis of CD remains a clinical one and is based on the combination of clinical, radiologic, endoscopic, and histologic findings. Although there is no reference standard for the diagnosis of CD, endoscopic demonstration of mucosal lesions, with associated histologic findings of chronic intestinal inflammation, is often critical in reaching the diagnosis. Practice guidelines increasingly recognize that CE may play a role in the diagnosis and the evaluation of the extent and activity of small intestine CD. Recent comparative studies suggest that CE has a greater sensitivity for mucosal inflammatory changes than radiologic imaging modalities. However, the clinical significance of some of these mucosal lesions is unclear. The frequency of false-positive reporting of minor mucosa] lesions and overdiagnosis of CD, in addition to an increased frequency of capsule retention in patients with known CD, may limit widespread application of CE in the workup of CD. This technical review examines published data on the utility of CE in CD to offer an evidence-based consensus framework for the safe and appropriate use of capsule examinations in patients with CD. colonoscopy. However, isolated involvement of the proximal small intestine can occur in as many as one third of cases, I and therefore normal findings on ileocolonoscopy are not sufficient to exclude the diagnosis. Assessment of the full length of the small intestine, traditionally by means of a radiologic examination, is typically required to evaluate patients with both suspected and established CD. Recent years have seen an expansion in both radiologic and endoscopic techniques available for small-bowel evaluation. Traditional contrast-enhanced radiology in the form of small-bowel follow-through (SBFT) or enteroclysis has been increasingly replaced by dedicated contrast-enhanced CT enterography (CTE) and more recently by magnetic resonance (MR) imaging (MR enterography [MRE]). Endoscopic techniques use either flexible video endoscopes, advanced through the small intestine by balloon or other intubation devices, or wireless video capsules (capsule endoscopy [CE]). CE, in particular, is increasingly advocated as an alternative to radiologic techniques for imaging the small intestine in CD, offering enhanced direct visualization of the small-bowel mucosa in a relatively noninvasive manner. However, debate persists about the proper place of CE relative to other techniques in the realm of inflammatory bowel disease (IBD). This technical review critically evaluated the utility of CE relative to other imaging modalities in specific situations for patients with both suspected CD and established CD. We also review the complications of CE and ultimately propose a framework for the safe and appropriate use of CE in CD.