脑膜瘤颅外侵及的MRI表现

MRI Features of Extracranial Meningioma Invasion

目的探讨脑膜瘤颅外侵及的MRI表现。方法对30例脑膜瘤颅外侵及患者均行MRI平扫及增强扫描。MRI平扫:使用头颅专用线圈,应用自旋回波T1WI、T2WI、P(D)WI序列,行横断、冠状及矢状面3个方位的扫描;扫描参数为:T1WI:TR/TE=400 ms.20 ms-1,T2WI:TR/TE=2 300 ms.100 ms-1,NEX=2次,矩阵160×256,FOV22,层厚7 mm,层间距2 mm。增强扫描:采用钆喷酸葡氨增强剂0.1 mmol.kg-1,扫描层面与平扫一致。结果 30例患者中,肿瘤为新月形25例(83.33%)、结节状5例(16.67%),肿瘤为新月形所占比例明显高于结节状(χ2=46.98,P<0.05);瘤脑界面清楚26例(86.67%)、不清楚4例(13.33%),瘤脑界面清楚所占比例明显高于不清楚(χ2=50.98,P<0.01);肿瘤强化均匀28例(93.33%)、不均匀2例(6.67%),肿瘤强化均匀所占比例明显高于不均匀(χ2=53.67,P<0.01);脑膜尾征长度为Rmax>5 cm 27例(90.00%)、Rmax≤5 cm 3例(10.00%),脑膜尾征长度为Rmax>5 cm所占比例明显高于Rmax≤5 cm(χ2=51.49,P<0.01)。MRI示:颅内外肿块,肿瘤邻近的颅骨增生、破坏。结论脑膜瘤颅外侵及有较典型的MRI表现,充分认识脑膜瘤颅外侵及的MRI特征,对术前正确诊断及治疗计划的选择等均有较大的帮助。

Objective To explore the MRI features of extracranial meningioma invasion.Methods Thirty patients with extracranial meningioma invasion underwent plain and enhanced MRI.The plain MIR was performed using dedicated head coil.The imaging was performed with spin echo T1WI（TR/TE = 400 ms·20 ms^-1）,T2WI（R/TE=2 300 ms·100 ms^-1） and P（D） WI sequences（NEX=2 times,matrix 160×256,FOV22,slice thickness 7 mm,slice gap 2 mm） in sagittal,coronal and transverse orientations.Enhanced MRI was performed using gadopentetate dimeglumine（0.1 mmol·kg^-1）,and the scanning plane was in the same plane as the plain scanning.Results The proportion of patients with crescent-shaped tumor（83.33%,25 patients） was significantly higher than that of patients with nodular tumor（16.67%,5 patients）（χ2= 46.98,P〈0.05）.The proportion of clear brain tumor interface（86.67%,26 patients） was higher than that of unclear brain tumor interface（13.33%,4 patients）（χ2 = 50.98,P〈0.01）.The proportion of homogeneous tumor enhancement（93.33%,28 patients） was higher than that of heterogeneous enhancement（6.67%,2 patients）（χ2=53.67,P〈0.01）.The proportion of dural tail sign length Rmax〉 5 cm（90.00%,27 patients） was higher than that of dural tail sign length Rmax ≤5 cm（10.00%,3 patients）（χ2 = 51.49,P〈0.01）.MRI showed intracranial tumor and adjacent skull hyperplasia and destruction.Conclusion Extracranial meningioma invasion has typical MRI appearance.It is important to understand MRI features of extracranial meningioma invasion for preoperative diagnosis and choice of treatment.