Department of Radiology, National Hospital Organization, Higashi-ohmi General Medical Center, 255 Gochi-cho, Higashiomi, Shiga, 527-8505, Japan.
Department of Radiology, Shiga University of Medical Science, Seta, Tsukinowa-cho, Otsu, Shiga, 520-2192, Japan.
Jpn J Radiol. 2021 Mar;39(3):209-224. doi: 10.1007/s11604-020-01053-w. Epub 2020 Oct 9.
Gastrointestinal tract lesions are major causes of acute abdominal pain. A rapid, accurate, and reliable diagnosis is required to manage patients. Magnetic resonance imaging (MRI) is a nonionizing modality that is beneficial for pregnant women, children, and young adults who are sensitive to ionizing radiation. For patients with renal impairment who are not accurately diagnosed with noncontrast computed tomography, noncontrast MRI can serve as an alternative diagnostic modality. MRI protocols used for acute abdominal pain are supposed to be optimized and prioritized to shorten scanning times. Single-shot T2-weighted and fat-suppressed T2-weighted imaging are important pulse sequences that are used to reveal pathology and inflammation in the gastrointestinal tract. Diffusion-weighted imaging clearly depicts inflammation and abscesses as hyperintense lesions. Most acute gastrointestinal tract lesions, including inflammation, ischemia, obstruction, and perforation, demonstrate bowel wall thickening. Bowel obstruction and adynamic ileus present bowel dilatation, and perforation and penetration show bowel wall defects. MRI can be used to reveal these pathological findings with some characteristics depending on their underlying pathophysiology. This review article discusses imaging modalities for acute abdominal pain, describes a noncontrast MRI protocol for acute abdominal pain caused by gastrointestinal tract lesions, and reviews MRI findings of acute gastrointestinal tract lesions.
胃肠道病变是急性腹痛的主要原因。需要快速、准确、可靠的诊断来治疗患者。磁共振成像(MRI)是非电离方式,对孕妇、儿童和对电离辐射敏感的年轻成年人有益。对于肾功能不全且不能通过非增强 CT 准确诊断的患者,非增强 MRI 可以作为替代诊断方式。用于急性腹痛的 MRI 方案应进行优化和优先级排序,以缩短扫描时间。单次激发 T2 加权和脂肪抑制 T2 加权成像(T2WI)是显示胃肠道病变和炎症的重要脉冲序列。弥散加权成像(DWI)可清晰显示炎症和脓肿呈高信号病变。大多数急性胃肠道病变,包括炎症、缺血、梗阻和穿孔,都表现为肠壁增厚。肠梗阻和无动力性肠梗阻表现为肠腔扩张,穿孔和穿透则表现为肠壁缺损。MRI 可以根据其潜在的病理生理学特征显示这些病理发现。本文讨论了用于急性腹痛的影像学方式,描述了用于胃肠道病变引起的急性腹痛的非增强 MRI 方案,并综述了急性胃肠道病变的 MRI 表现。