Enterography

Enterography

Enterography is a specialized imaging technique used in the field of radiology to visualize the small intestine. It is particularly useful for diagnosing and evaluating conditions such as Crohn's disease, small bowel tumors, and other pathologies affecting the small intestine. Enterography can be performed using either magnetic resonance imaging (MRI) or computed tomography (CT), known as MR enterography (MRE) and CT enterography (CTE), respectively.

History

The development of enterography as a diagnostic tool has evolved with advancements in imaging technology. Initially, traditional barium studies were used to assess the small bowel, but these have largely been replaced by more advanced techniques like CT and MR enterography, which provide superior detail and do not involve ionizing radiation in the case of MRI.

Techniques

CT Enterography

CT enterography involves the use of computed tomography to obtain detailed images of the small intestine. Patients are typically required to drink a large volume of oral contrast material, which helps to distend the bowel and improve visualization. Intravenous contrast is also administered to enhance the images. CT enterography is particularly useful for detecting bowel wall thickening, strictures, and extraluminal complications such as abscesses or fistulas.

MR Enterography

MR enterography uses magnetic resonance imaging to visualize the small bowel. Like CT enterography, it requires the ingestion of oral contrast to distend the bowel. MR enterography is advantageous because it does not use ionizing radiation, making it a preferred choice for younger patients and those requiring repeated imaging. It provides excellent soft tissue contrast and is effective in assessing bowel wall inflammation, edema, and fibrosis.

Indications

Enterography is indicated in the evaluation of:

• Inflammatory bowel disease, particularly Crohn's disease
• Small bowel tumors
• Unexplained gastrointestinal bleeding
• Celiac disease with suspected complications
• Small bowel obstruction

Advantages and Limitations

Advantages

• Non-invasive: Both CT and MR enterography are non-invasive procedures.
• Detailed imaging: Provides high-resolution images of the small bowel and surrounding structures.
• Functional assessment: MR enterography can assess bowel motility and function.
• No radiation (MRI): MR enterography does not involve ionizing radiation, making it safer for repeated use.

Limitations

• Preparation: Requires bowel preparation and ingestion of oral contrast, which some patients may find uncomfortable.
• Availability and cost: MR enterography may not be as widely available as CT and can be more expensive.
• Contraindications: MRI is contraindicated in patients with certain implants or devices.

Preparation and Procedure

Patients undergoing enterography are typically instructed to fast for several hours before the procedure. They will be asked to drink a large volume of oral contrast over a specified period to ensure adequate bowel distension. During the procedure, patients may receive intravenous contrast to enhance the images. The entire process, including preparation, can take several hours.

Also see

• Crohn's disease
• Magnetic resonance imaging
• Computed tomography
• Inflammatory bowel disease
• Small bowel obstruction