微囊型脑膜瘤的MRI表现

MRI Findings of Microcystic Meningioma

目的探讨微囊型脑膜瘤(MCM)的MRI表现及其诊断价值。资料与方法回顾性分析8例经手术病理证实的MCM患者的影像学及病理资料,并与病理对照。结果病变位于额部6例(左侧4例,右侧2例),右侧顶部大脑镰旁1例,右侧桥脑小脑角区1例;8例中5例平扫T1WI呈低信号,T2WI呈明显高信号,增强后病变呈明显不均匀强化;3例平扫时T1WI呈不均匀等低信号,T2WI呈不均匀等高混杂信号,增强后病变呈明显不均匀强化;8例病变中4例可见"脑膜尾征";6例可见中重度瘤周水肿;肿瘤组织中见瘤细胞排列疏松,呈微囊状。结论 MCM是颅内少见肿瘤,MRI表现有一定特点,T2WI呈明亮高信号,增强后呈明显强化,MRI对其诊断和鉴别诊断具有重要临床价值。

Objective To investigate the MRI feature and diagnostic value of microcystic meningioma compared with pathological findings.Materials and Methods The MRI and clinical data of 8 patients with microcystic meningioma confirmed by pathology were retrospectively reviewed.Results There were 6 cases located in frontal lobe（4 in left and 2 in right）,1 case in the right parietal lobe next to cerebral falx,1 case in right CPA.Five cases showed hypointensity on T1WI,hyperintensity on T2WI.and heterogeneous enhancment.Three cases showed iso-to hypointensity on T1WI,iso-to hyperintensity on T2WI and heterogeneous enhancment.Meningeal tail sign was showed in 4 cases.Six cases showed moderate to severe peritumoural edema.In tumor tissues,the tumor cells loosely arranged as multi-microcystic type.Conclusion Microcystic meningioma is a rare intracranial tumor,which has some MRI characteristics,such as hyperintensity on T2WI and heterogeneous enhancement.Correct diagnosis and differential diagnosis can be made using MRI.