Magnetic resonance imaging in children and adolescents with chronic inflammatory bowel disease

Abstract

Inflammatory bowel diseases (IBD) represent challenges, both from a diagnostic, and therapeutic point of view. Deep-seated anatomic structures are difficult to assess by ultrasound technique alone. As radiation-free alternative cross-sectional imaging method, magnetic resonance imaging of the intestinal structures is costly and time-consuming. Examination of pediatric patients imply additional considerations: reduction of body motions in younger children and consideration of the most appropriate preparation, and examination technique. The demanding Sellink technique is the only means for appropriately distending the lesser intestine in order to detect small bowel strictures. Oral intake of contrast medium (CM) alone shows its limitations regarding distensibility. The need for intravenous contrast media application needs to be considered, too. Active inflammation of both intestinal wall, and mesentery can be demonstrated accurately. Nevertheless, viable alternatives to CM application is desirable, considering non-negligible adverse reactions. Recent data suggest diffusion weighted imaging might fill this diagnostic gap. Irrespective of sequence technique chosen, bowel movement remains a major obstacle. Antispasmolytics in their function as smooth muscle relaxants help in improving image quality, however, their use in children might be off-label. Optimal preparation for the examination and appropriate imaging technique allow for diagnosing typical patterns of changes in IBD, such as bowel wall thickening, ulcers, mural stratification, strictures, creeping fat, and comb sign, and lymphadenopathy. The article gives a detailed overview of current significance of magnetic resonance imaging pediatric patients suffering from IBD, considering indications, limitations, and safety aspects.

Keywords: Children; Adolescents; Inflammatory bowel disease; Crohn’s disease; Ulcerative colitis; Magnetic resonance imaging; Enterography

Core tip: Diagnosis of chronic inflammatory bowel disease (IBD) is partially based on subsequent imaging. Magnetic resonance imaging (MRI) of the gastrointestinal tract (GIT) is established in adults for diagnosing IBD. In children and adolescents MRI is not routinely used up to now. This manuscript presents the commonly used magnetic resonance sequences for the evaluation of the GIT in children and adolescents. Techniques to obtain optimal bowel distension by oral intake or by using a nasally placed tube are described. Typical findings of intestinal and mesentery pathology in children suffering from IBD are shown.