磁共振对颅内脑膜瘤的诊断（附65例分析）

Diagnosis of Meningiomas With MR(An analysis of 65 cases)

本文通过对６５例颅内脑膜瘤的信号变化分析，发现６９％的脑膜瘤其信号变化和脑灰质信号变化同步，２０％的脑膜瘤信号随着回波时间的延长而升高，１１％的脑膜瘤信号在Ｔ２加权像上为混杂信号。同时，得出磁共振对脑膜瘤的正确诊断率达９２．３％，脑膜瘤被磁共振误诊为其他肿瘤的达７．７％，并探讨了误诊原因及误诊病变的好发部位。：以等信号为主，可见少量低信号表２６５例手术证实的脑膜瘤的ＭＲ所见二、ＭＲ的诊断和手术病理结果对照经手术和病理证实的脑膜瘤６５例，其中６０例ＭＲ诊断和手术病理诊断一致，５例ＭＲ诊断和手术病理不符，因此ＭＲ对脑膜瘤的正确诊断率为９２．３％；脑膜瘤被ＭＲ误诊为其他肿瘤的误诊率为７．７％。５例ＭＲ诊断和手术病理诊断不符情况见表３，ＭＲ分别诊断为胶质瘤、三叉神经瘤、血管瘤、垂体瘤和听神经瘤，而手术和病理证实为脑膜瘤（图３～５）。５例误诊脑膜瘤分别位于丘脑、海绵窦、鞍区、桥小脑角区。这些解剖部位为相对较特殊的区域。图１示发生于四叠体池的脑膜瘤，同一层面的ＳＥ序列的四个加权图像，示肿瘤的信号变化同胞灰质变化基本同步。图２ 示左侧颞部的脑膜瘤，其瘤体的信号变化在Ｔ１加权，质子密度加权及Ｔ２加权图像基本与脑灰质信号一致?

The signal change of 65 meningiomas were analyzed in this article.The authors found that:(1)69% of meningiomas displayed homogeneous signal similar to that of gray matter;(2) 20% of meningiomas signal increased as spin echo time being prologed;(3)11% of meningiomas exhibited mixed signal.Meanwhile,it was found that the correct diagnostic rate with MR was 92.3%; the error diagnostic rate with MR was 7.7%,in which meningiomas were mistaken for other tumors.The cause of misdiagnosis and the location of misdiagnosed meningiomas were discussed.