MR Enterography

Magnetic Resonance Enterography (MRE) is a radiological technique that has evolved in the last decade. It involves the use of magnetic resonance imaging (MRI) to assess the small bowel, following distension with an oral contrast agent.
The advantages of this technique are that it involves no ionising radiation, is capable of multi-planar imaging, affords high-contrast resolution (with more detailed evaluation of bowel wall changes) and allows for cine-imaging.
Its main indication at present is to evaluate small bowel involvement in patients with Crohn’s disease ( is a chronic inflammatory bowel condition with onset usually in young adulthood. Twenty to thirty percent of patients are younger than 20 years old)

                                           

Common uses of this procedure (MR enterography) to identify and locate

• The presence of and complications from Crohn's disease and other inflammatory bowel diseases
• Inflammation
• Bleeding sources and Vascular abnormalities
• Tumors
• Abscesses and Fistulas
• Bowel obstructions.

Main sequence used in MRE

Coronal True FISP image: normal bowel. The ‘black boundary’ artefact may be confused with bowel wall thickening (arrows)

Coronal T1 fat-saturated post-contrast image: normal bowel wall shows mild homogeneous enhancement

Coronal fat-saturated HASTE image: normal bowel. Intraluminal flow voids (arrow) are seen, as this sequence is sensitive to fluid motion.

Example of mural thickening in active Crohn’s disease: a axial True FISP image shows mural thickening in the distal ileum (arrow); b coronal True FISP in a different patient (15 years old) shows extensive jejunal small bowel wall thickening

Example of pseudosacculation: coronal True FISP image shows two long skip lesions in the mid to distal ileum (asterisk) demonstrating mural thickening, luminal narrowing and prominence of the vasa recta (arrowheads) with small nodes seen within the mesentery.