Current Progress of Endoscopy in Inflammatory Bowel Disease: MR Enterography

Abstract

Crohn’s disease (CD) is a lifelong, chronic, progressive inflammatory disease of the gastrointestinal tract associated with diarrhea, abdominal pain, bloody stool, and often perianal fistulae. Inflammation throughout the small and large bowels causes irreversible bowel damage, such as strictures, fistulae, and abscesses, despite achieving clinical remission. To optimize therapy for CD, it is necessary to monitor disease activity and evaluate therapeutic interventions. Evaluations based on clinical activity alone are not sufficient, and frequent imaging examinations, particularly of the small bowel, are important. In recent years, many new imaging modalities have been developed, such as video capsule endoscopy (VCE), balloon-assisted enteroscopy (BAE), ultrasonography (US), computed tomography enterography (CTE), and magnetic resonance enterography/enterocolonography (MRE/MREC). A suitable imaging modality should be reproducible, well-tolerated, safe, and free of ionizing radiation because CD is a lifelong disease. MRE and MREC are cross-sectional imaging techniques used to investigate not only extraluminal abnormalities but also intraluminal changes. Recent advances have enabled the use of MRI to assess bowel disorders with high levels of sensitivity, specificity, and accuracy. MRI can evaluate not only intrabowel lesions but also extrabowel lesions, including abdominal abscesses and perianal lesions while eliminating the problem of overlapping bowel loops. Therefore, MRI could potentially be used to evaluate overall CD activity without causing radiation exposure. MRE and MREC are, therefore, suitable first-line imaging modalities for the assessment of CD.