目的 探讨MRI对椎管内神经源性 肿瘤和脊膜瘤的诊断与鉴别诊断价值。 方法 回顾性分析了20例经手术和病理证 实的椎管内髓外硬膜下肿瘤的MRI表现， 其中神经鞘瘤10例，神经纤维瘤3例，脊 膜瘤7例，采用GE3.0T 磁共振仪进行扫 描。结果 肿瘤的发生部位、与硬膜面的 夹角、囊变坏死、强化方式及硬膜尾征在 神经源性肿瘤(神经鞘瘤和神经纤维瘤)和 脊膜瘤间存在明显差异，两组间进行比 较，差异有统计学意义(P<0.05)；神经源 性肿瘤与脊膜瘤T1WI信号无明显差异；神 经鞘瘤T2WI信号多不均匀；脊膜瘤T2WI多 呈等或稍高信号，若发生钙化，则T1WI、 T2WI呈低信号改变。结论 神经源性肿瘤 和脊膜瘤都有特征性MRI表现，MRI是临床 诊断和鉴别诊断神经源性肿瘤和脊膜瘤的 重要手段

Objective To evaluate the signs of primary subdural extramedullary tumors so as to improve the level of diagnosis and differential diagnosis. Methods We retrospectively reviewed the clinical data and MR images of 20 consecutive patients with surgically and pathologically proven subdural extramedullary tumors including 10 cases of neurinoma, 3 cases of neurofibroma and 7 cases of meningioma. Results There were significant difference between the MR signs of spinal neurogenic tumors and meningioma in the locations of the tumors, the angle to spinal dure mater, dural tail sign, cystic or necrosis in tumor and the features of enhancement scanning(P<0.05). However, there were no significant difference between the MR intensity of neurogenic tumors and that of meningioma in T1WI, the MR intensity of Schwannoma was heterogeneous in T2WI, and that of meningioma was even or slightly hyperintense signal in T2WI. Conclusion The neurogenic tumors and meningioma have characteristic MRI findings, and the MRI is an important method for clinical diagnosis and differential diagnosis of neurogenic tumors and meningioma.