Magnetic resonance enterography (MRE)

Magnetic resonance enterography (MRE) is a specialized MRI that images the small intestine using oral contrast and sometimes IV gadolinium to highlight bowel wall, inflammation, strictures, fistulas and abscesses. It is non‑ionizing, typically requires fasting and drinking contrast before the 30–60‑minute scan, and is especially useful for Crohn’s disease monitoring. Gadolinium is usually safe but used cautiously in severe kidney impairment.

MRE can mean two MRI techniques. Magnetic resonance enterography images the small and large bowel to diagnose or monitor inflammatory bowel disease (Crohn’s), strictures, fistulas and tumors. Magnetic resonance elastography measures tissue stiffness—commonly used to assess liver fibrosis and cirrhosis noninvasively. Both are non‑ionising, use MRI scanners, and help guide diagnosis, treatment decisions and monitoring.

MRI (magnetic resonance imaging) creates detailed images of internal anatomy and soft tissues using magnetic fields and radio waves. MRE (magnetic resonance elastography) adds low-frequency mechanical vibrations and specialized processing to map tissue stiffness and produce quantitative elasticity values. MRE uses the same scanner with an external vibration driver and is especially useful for detecting fibrosis or tumors by measuring altered tissue stiffness noninvasively.

MR enterography is usually not painful. It’s a noninvasive MRI exam; most people feel only mild, temporary discomfort from drinking large volumes of oral contrast (bloating, cramping) and occasional brief stinging when IV contrast is injected. Lying still in the scanner can be uncomfortable and noisy; claustrophobic patients may need sedation. Severe pain is uncommon—tell staff if you experience significant pain.

Beforehand you may be asked to fast for a few hours and remove metal. During an MRE you’ll lie on the MRI table and a technologist will place a soft vibrating pad over the area (commonly the liver). The machine makes loud noises; you must lie still and follow brief breath-hold instructions. The vibration is harmless and the exam is usually painless, taking about 15–30 minutes. Results go to your doctor.

MR enterography avoids ionizing radiation and gives superior soft‑tissue contrast, making it preferable for young patients and for assessing inflammation, fistulae and bowel wall detail in chronic conditions. CT is faster, more widely available, better for acute bleeding, bowel perforation or when MR is contraindicated. Choice depends on clinical question, patient factors, availability and urgency.