Imaging of the colon in inflammatory bowel disease: ready for prime time?

Endoscopy is currently considered the reference standard for the evaluation of disease activity and severity in patients with inflammatory bowel disease (IBD). However, information provided by endoscopy is limited to the mucosal surface and cannot always be complete. Cross-sectional imaging techniques are gaining acceptance for the assessment of patients with Crohn's disease (CD) and ulcerative colitis (UC). Overall diagnostic accuracy of ultrasonography (US), computed tomography (CT) and magnetic resonance imaging (MRI) for the evaluation of colonic lesions in patients with IBD is high. The main limitation of US is its high dependence on expertise of the examiner and the anatomic location of lesions, and its main strengths are wide availability safety and low cost. CT is highly accurate for the evaluation of patients with IBD, but due to safety issues related to radiation exposure this technique should be reserved for urgent situations in which US is not diagnostic. Technological advances in the area of MRI have allowed optimization for the assessment of patients with IBD, mainly CD. Available evidence suggests that magnetic resonance colonography (MRC) has a high diagnostic accuracy for the detection of disease activity, location, severity, and complications, particularly for penetrating and stricturing lesions, characteristic of CD. MRC can provide a valuable guidance for performing medical and surgical treatment with maximized efficacy and safety. Overall, MRI findings accurately reflect disease activity and provide reliable information for decision-making and patient care optimization.