Korean J Gastroenterol.  2020 Feb;75(2):86-93. 10.4166/kjg.2020.75.2.86.

Preparation, Technique, and Imaging of Computed Tomography/Magnetic Resonance Enterography

• Kim MJ

• KMID: 2471147
• DOI: http://doi.org/10.4166/kjg.2020.75.2.86

Abstract

CT enterography and magnetic resonance (MR) enterography are widely used imaging modalities used to examine the small bowel. These radiologic tests are distinguished from routine abdominopelvic CT and MRI by the oral ingestion of a large amount of neutral contrast to distend the small bowel before scanning. For achievement of high quality, diagnostic images and proper technique are required. Conducted protocols still vary in patient preparation, enteric contrast, and CT and MRI acquisition sequences, resulting in heterogeneous diagnostic accuracy. The purpose of this article is to review the processes and techniques that optimize CT/MR enterography for patients with suspected Crohn's disease or other small bowel diseases.

Keyword

Diagnostic imaging; Multidetector computed tomography; Magnetic resonance imaging; Intestine, small

MeSH Terms

Crohn Disease
Diagnostic Imaging
Eating
Humans
Intestine, Small
Magnetic Resonance Imaging
Multidetector Computed Tomography

Figure

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  Fig. 1. Computed tomography enterography of active Crohn's disease. Axial image (A) showed bowel wall thickening, mucosal enhancement and edema (arrows). (B) Coronal image demonstrated mesenteric vessel engorgement (comb sign, arrow) with lymph node enlargement (arrowhead). (C, D) Coronal image (C) and axial image (D) noted star-shaped entero-enteric fistula (arrows).

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  Fig. 2. Magnetic resonance enterography of active Crohn's disease. (A) Coronal scan of postcontrast T1-weighted image showed mucosal enhancement, wall thickening (arrow), and mesenteric vessel engorgement. (B) Coronal scan of true fast imaging with steady-state precession (FISP) noted intermediate signal intensity of involved ileal segment (arrow). (C, D) Diffusion-weighted image (C, high b-value=1,000) and apparent diffusion coefficient (ADC) (D) images demonstrated diffusion restriction presenting active inflammation (arrows).

Reference

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