放射性脑脊髓坏死的MRI诊断

MRI diagnosis of radiation myeloencephalic necrosis

目的 评价放射性脑脊髓坏死（ｒａｄｉａｔｉｏｎ ｍｙｅｌｏｅｎｃｅｐｈａｌｉｃ ｎｅｃｒｏｓｉｓ，ＲＭＥＮ） 的ＭＲＩ表现及其诊断价值。方法 回顾性分析９ 例经临床、ＭＲＩ诊断或手术病理证实的ＲＭＥＮ。结果 ９ 例ＲＭＥＮ中，放射性脑坏死（ｒａｄｉａｔｉｏｎ ｅｎｃｅｐｈａｌｉｃ ｎｅｃｒｏｓｉｓ，ＲＥＮ） ４ 例，放射性脊髓坏死（ｒａｄｉａｔｉｏｎ ｍｙｅｌｏｎｅｃｒｏｓｉｓ，ＲＭＮ）５ 例，共１１ 个病灶。其共同ＭＲＩ特征为：主要累及白质；Ｔ１ＷＩ呈低信号，Ｔ２ＷＩ呈高信号、中央见等信号区；增强后全部病灶均被强化、中央有非强化区；邻近骨髓明显脂肪沉积；齿轮状外观是ＲＥＮ的特征。而ＲＭＮ 特征为长节段脊髓受累与相对小的强化灶及刺状或指状边缘。结论 ＲＭＥＮ 的ＭＲＩ表现具有一定特征，结合放射治疗病史，大部分病例可做出正确诊断。

Objective To evaluate MRI findings and the diagnostic value of radiation myloencephalic necrosis (RMEN) Methods Nine cases of RMEN diagnosed by clinical manifestations、MRI or operation and pathology were retrospectively analyzed Results Among the 9 cases, 4 were radiation encephalic necrosis (REN) , and the others were radiation myelonecrosis(RMN) A total of 11 lesions were found The common MRI findings were: chiefly involving the white matter, short T 1 and long T 2 with iso signal intensity focus in the center; all lesions enhanced by Gd DTPA, but ten had a non enhancing focus in the center; fatty deposition of nearby bone marrow Gear like margin was the characteristic feature of REN Long segment involvement with small enhancing focus and thorn like or paw like margin was the features of RMN Conclusion Most cases of RMEN can be diagnosed correctly according to the MRI characteristic findings combined with radiation history