Department of Radiologic Imaging, Hôpital Robert Debré, Avenue du Général Koenig, 51092 Reims, France.
Radiographics. 2012 Sep-Oct;32(5):1423-44. doi: 10.1148/rg.325115088.
The use of cross-sectional imaging techniques for the noninvasive evaluation of small-bowel disorders is increasing. The effectiveness of magnetic resonance (MR) enterography for the evaluation of Crohn disease, in particular, is well described in the literature. In addition, MR enterography has an evolving though less well documented role to play in the evaluation of other small-bowel diseases, including various benign and malignant neoplasms arising in isolation or in polyposis syndromes such as Peutz-Jeghers, inflammatory conditions such as vasculitis and treatment-induced enteritis, infectious processes, celiac disease, diverticular disease, systemic sclerosis, and bowel duplication. MR enterography may be useful also for the evaluation of intermittent and low-grade small-bowel obstructions. Advantages of MR imaging over computed tomography (CT) for enterographic evaluations include superb contrast resolution, lack of associated exposure to ionizing radiation, ability to acquire multiplanar primary image datasets, ability to acquire sequential image series over a long acquisition time, multiphasic imaging capability, and use of intravenous contrast media with better safety profiles. MR enterography also allows dynamic evaluations of small-bowel peristalsis and distensibility of areas of luminal narrowing and intraluminal masses by repeating sequences at different intervals after administering an additional amount of the oral contrast medium. Limitations of MR enterography in comparison with CT include higher cost, less availability, more variable image quality, and lower spatial resolution. The advantages and disadvantages of MR enterography performed with ingestion of the oral contrast medium relative to MR enteroclysis performed with infusion of the oral contrast medium through a nasoenteric tube are less certain.
使用横断面成像技术对小肠疾病进行非侵入性评估的应用正在增加。磁共振（MR）肠成像在克罗恩病评估中的有效性在文献中已有很好的描述。此外，MR 肠成像在评估其他小肠疾病方面具有不断发展但记录较少的作用，包括各种孤立或息肉综合征（如 Peutz-Jeghers 综合征）中发生的良性和恶性肿瘤、炎症性疾病（如血管炎）和治疗诱导性肠炎、感染过程、乳糜泻、憩室病、系统性硬化症和肠重复。MR 肠成像也可用于评估间歇性和低度小肠梗阻。MR 成像相对于 CT 用于肠成像评估的优势包括出色的对比分辨率、无相关电离辐射暴露、获取多平面原始图像数据集的能力、在长时间采集期间获取连续图像序列的能力、多相成像能力以及使用具有更好安全性的静脉内对比剂。MR 肠成像还允许通过在给予额外量口服对比剂后在不同时间间隔重复序列，动态评估小肠蠕动和肠腔狭窄区域的可扩展性以及腔内肿块。与 CT 相比，MR 肠成像的局限性包括成本更高、可用性更低、图像质量更可变以及空间分辨率更低。口服对比剂摄入的 MR 肠成像与通过鼻肠管输注口服对比剂的 MR 肠腔成像相比，其优缺点不太确定。
