急性播散性脑脊髓炎的脑部MRI表现

目的　描述急性播散性脑脊髓炎的脑部MRI表现 ,探讨MRI对该病的诊断价值以及在评价疗效中的作用。方法　符合临床诊断标准的急性播散性脑脊髓炎患者 9例 ,男 8例 ,女 1例 ,年龄 9～ 47岁。 6例发病前有病毒感染或疫苗接种史。全部 9例行头部MRI检查 ,7例行MRI复查。结果　病变多发且分布不对称 ,9例大脑白质受累 ,6例同时累及丘脑 ,4例可见“垂直征” ,病变呈大小不等的片状或点状异常信号 ,6例可见异常对比增强 ,7例复查见异常信号缩小且数目减少。结论急性播散性脑脊髓炎的MRI脑部表现颇具特征性 ,结合病史及单时相病程可作出早期诊断 ,MRI随访是评价疗效的重要手段。MRI显示丘脑受累是鉴别本病与多发性硬化的主要依据。

MR imaging of the brain in acute disseminated encephalomyelitis

Objective To describe the MR findings of the brain in acute disseminated encephalomyelitis (ADEM), and to evaluate the usefulness of MR imaging in diagnosing ADEM and assessing the therapy. Methods Nine cases of clinically proven ADEM were retrospectively reviewed. There were 8 males and 1 female with the age ranging from 9 to 47 years. Six patients had a history of viral infection or vaccination prior to the onset of ADEM. MR scanning of the brain was performed in all cases in acute stage and follow up MR imaging was achieved in 7 cases. Results Multiple and asymmetrical lesions were revealed in the white matter (9 cases), thalami (6 cases), brainstem, cerebellum, and the gray matter. The pattern of perpendicular distribution against the lateral ventricles was detected in 4 cases. Patchy or punctuate abnormal signal intensities with various size were demonstrated in all patients and contrast enhancement was observed in 6 cases. Follow up MR imaging showed that the abnormal signals decreased in both size and number. Conclusion MR findings of the brain in ADEM has some characteristics by which early diagnosis could be made if combined with the history and monophasic clinical setting. Follow up MR imaging plays an important role in further confirming the diagnosis, and in evaluating the therapy as well. Thalamic involvement as showed by MR imaging proved useful in distinguishing between ADEM and multiple sclerosis.