侧脑室内脑膜瘤的MRI诊断与鉴别诊断

MRI diagnosis and differential diagnosis of meningioma in lateral ventricle

目的探讨侧脑室内脑膜瘤的MRI表现及与其它脑室内肿瘤的鉴别诊断。方法对经手术病理证实的6例侧脑室内脑膜瘤的临床、病理及MRI资料进行回顾性分析。结果本组术前MRI诊断定位正确率为100%,定性正确率为66.7%(4/6)。其MRI特征性表现为:(1)肿瘤呈类圆形,边界清楚,在T1WI上为等低信号,T2WI为等高信号。(2)侧脑室扩大不明显,脑积水程度较轻。(3)增强后,均存在中至高度强化。结论侧脑室内脑膜瘤的MRI表现有一定的特征性,其病理基础是在胚胎发育形成脉络丛及血管膜的过程中,部分蛛网膜被带入脑室后发展而来;MRI可以对其进行诊断并和脑室内的其它肿瘤进行鉴别。

Objective To study the MRI features and differe ntial diagnosis of meningioma in the lateral ventricle.Methods The clini-cal data,pathological basis and MRI findings in 6patients with pathologically proved the meningioma within lateral ventricles were analyzed retrospectively.Results The localized and qualitative accur acy of preoperative MRI examination s were 100%and 66.7%,respective-ly.The characteristic MRI appearan ces of meningioma in the lateral vent ricle were as follows:(1)the tumor tended to be roundish in shape and sharply demarcated.The tumor pr esented iso /hypointense on T 1 WI and iso /hyperintense on T 2 WI;(2)the lateral ventricles were en-larged unconspicuous and were sligh tly hydrocephaloid;(3)moderate to strong enhancement in di fferent degrees of tumor could be see n on T 1 WI after injection of Gd -DTPA in all cases.Conclusion MRI can demonstrates the meningioma in the lateral ventricle well charac teristic appearance,whose pathological basis is that some arachnoid had beed ent ered into the lateral ventricle during the growth period of choroid and intima and is possible to deffere ntiate from other tumors in the lateral ventricle.[