脑膜瘤和星形细胞瘤瘤周水肿的MRI对照研究

Comparision of MRI Appearances of Peritumoral Edema in Meningiomas and Astrocytomas

目的：比较脑膜瘤和星形细胞瘤瘤周水肿的MRI特点。材料和方法：对88例星形细胞瘤MRI和51例脑膜瘤MRI进行统计学分析。结果：（1）51％脑膜瘤伴瘤周水肿，其中月晕型水肿11例（42．3％），指样型水肿10例（38．5％），混合型5例（19．2％）；86．4％星形细胞瘤伴瘤周水肿，均为指样型水肿。（2）当瘤体超过64cm3时，87％脑膜瘤和87．5％星形细胞瘤伴水肿，脑膜瘤轻度水肿占61．5％，星形细胞瘤重度水肿占78．6％；瘤体为8～64cm3时，44．4％脑膜瘤伴水肿，91．5％星形细胞瘤伴水肿；体积小于8cm3时，11．1％脑膜瘤伴水肿，且为轻度水肿，而61．5％星形细胞瘤伴不同程度水肿。（3）脑膜癌中，血管母细胞型水肿发生率较高（100％），纤维细胞型最低（25％）；星形细胞瘤中，Ⅲ～Ⅳ级水肿发生率最高。结论：MRI不同的水肿形态与肿瘤的来源有关，对此进一步研究将有助脑内、外肿瘤的鉴别诊断及瘤-脑界面的评价。

Purpose: To compare MRI appearances of peritumoral edema(PTE) in meningiomas and astrocytomas.Materials and Methods: Statistic analysis of MRI was done in 88 cases of astrocytomas and 51 cases of meningiomas. Results: (1)51% meningiomas were found to be associated with PTE, including halo- like and finger-like ones; On the other hand, 86. 4% astrocytomas only with finger-like PTE. (2) Among tumors whose sizes over 64cm3, 87% meningiomas and 87. 5% astrocytomas existed with PTE. PTE of grade 1 was 61 .5% in meningiomas, grade 3 was 78.6% in astrocytomas. In tumor volumes between 8and 64cm3, 44.4% meningiomas presented with PTE, 91.5% astrocytomas with PTE. With tumors smaller than 8 cm3, only 11. 1% meningiomas were associated with PTE(grede 1), 61. 5% astrocytomas with different grades of PTE. (3) Histologically, angioblastic meningiomas tended to be involved with the largest PTE, while fibroblastic meningiomas with the smallest PTE. Maligment astrocytomas of grade Ⅲ ～Ⅳ were always revealed to have the largest PTE. Conclusion: Different styles of PTE were found according to the nature of tumor. Further study of PTE may be helpful in differentiating tumors in or outside of the brain, and also useful in evaluating different brain tumor interfaces.