非典型部位脑膜瘤的MR诊断

目的：探讨颅内外非典型部位脑膜瘤的MR诊断。方法：回顾性分析32例经手术和病理证实的非典型部位（侧脑室、脑内、小脑、脑池、松果体区、眶内、颈静脉孔区、鼻窦）脑膜瘤的MR表现，32例脑膜瘤均进行了MR平扫及增强检查。结果：恶性脑膜瘤4例，良性28例；多发脑膜瘤2例，单发30例（颅内外沟通2例）。非典型部位脑膜瘤MR表现主要呈等T1等T2或稍高、稍低T1、T2信号的实质性肿块，信号均匀，呈圆形、类圆形或浅分叶状，强化均匀或呈“靶环”样强化。结论：脑膜瘤有较特征的影像学表现，结合临床资料，大多数非典型部位脑膜瘤可作出影像学定性诊断，对临床的术式选择有一定的指导意义。

MR diagnosis of atypical-location meningioma

Objective：To investigate the MR features of meningioma in atypical location.Methods：The MR features were analyzed retrospectively in 32 cases of meningioma in atypical location（lateral ventricular,brain,cerebellum,cistern,pineal region,orbit,jugular foramen region,paranasal sinus） proved by operation and pathology.Non-enhanced and contrast enhanced MR scanning were performed in all cases.Results：Malignant meningioma was found in 4 cases,benign in 28 cases;multiple meningiomas in 2 cases,single lesion in 30 cases（intra-extracranial communication meningioma in 2 cases）.The MR imaging feature of atypical location meningioma showed intraparenchymal tumor;homogeneous isointense or slightly hyperintense or slightly hypointense signal on T1WI and T2WI;the shapes of mass were round,round-like or lobulated,homogeneous enhancement or target ring sign were found on Gd-DTPA enhanced MR scanning.Conclusion：Meningioma has certain imaging characteristics,when combined with clinical data,most of the atypical location meningioma can be made qualitative diagnosis,and have a certain degree of significance in guiding the selection of the mode of surgical operation.