Sandhu F S, Dillon W P
Department of Radiology, University of California, San Francisco 94143-0628.
AJNR Am J Neuroradiol. 1991 Nov-Dec;12(6):1087-93.
Seven patients with spinal epidural abscess were evaluated with MR imaging. T1-weighted images were obtained before and after administration of gadopentetate dimeglumine, and contrast-enhanced images were compared with available T2-weighted images and unenhanced T1-weighted images. In all seven cases, the epidural infection was iso- to hypointense compared with the spinal cord on unenhanced T1-weighted images, and increased in intensity on proton-density- and T2-weighted images. Three patterns of enhancement were observed after contrast administration. In three patients the infection enhanced homogeneously, likely representing thickened, inflammed tissue with microabscesses and granulomatous material. In one patient, peripheral enhancement surrounded a central focus of low signal intensity, representing necrotic abscess. In two patients, a combination of both patterns was observed. One abscess infiltrated the posterior thoracic epidural fat, producing decreased signal within the high-signal fat on T1-weighted images. Enhanced T1-weighted images were equivalent to unenhanced T2-weighted images in detecting the extent of epidural involvement in three cases. In two cases, enhanced T1-weighted images were superior to T2-weighted images in differentiating the infectious component from surrounding CSF. In one case, contrast administration produced no discernible enhancement. Enhanced images also provided important information regarding the composition of the abscess (liquid versus solid). Contrast-enhanced MR images are valuable in the characterization of spinal epidural abscesses.
对7例脊髓硬膜外脓肿患者进行了磁共振成像（MR）评估。在静脉注射钆喷酸葡胺前后均获取了T1加权像，并将增强图像与现有的T2加权像和未增强的T1加权像进行了比较。在所有7例病例中，在未增强的T1加权像上，硬膜外感染灶相对于脊髓呈等信号至低信号，而在质子密度加权像和T2加权像上信号强度增加。注射造影剂后观察到三种强化模式。3例患者感染灶呈均匀强化，可能代表伴有微脓肿和肉芽肿物质的增厚、炎症组织。1例患者，外周强化包绕中心低信号灶，代表坏死性脓肿。2例患者观察到两种模式的组合。1例脓肿浸润胸段硬膜外脂肪，在T1加权像上高信号脂肪内信号减低。在3例病例中，增强T1加权像在检测硬膜外受累范围方面与未增强T2加权像相当。在2例病例中，增强T1加权像在区分感染成分与周围脑脊液方面优于T2加权像。1例病例中，注射造影剂后未见明显强化。增强图像还提供了有关脓肿成分（液体与固体）的重要信息。增强磁共振成像在脊髓硬膜外脓肿的特征性诊断中具有重要价值。
