侧脑室脑膜瘤的磁共振表现

MR imaging features of the lateral ventricular meningioma

目的通过分析侧脑室脑膜瘤的磁共振特征,以提高诊断准确性。方法分析手术病理证实的27例侧脑室脑膜瘤的磁共振资料,总结其磁共振影像特点。结果 25例位于侧脑室后角及三角区(其中19例位于左侧、6例位于右侧)、1例位于侧脑室体部、1例为多发。所有肿瘤MRI均表现为边界清楚的肿块影。22例肿瘤形态呈圆形(81.5%),5例浅分叶(18.5%),1例深分叶。信号均与脑灰质对比,T1WI呈等高或稍低信号,T2W/FLAIR呈等或稍高信号,与脑室外脑膜瘤信号基本一致。T1WI增强扫描多数为明显强化,并显示肿块边缘与脉络丛相连。肿瘤病理类型:19例为纤维型、8例为上皮型。测ADC平均值分别为纤维型(0.89±0.12)×10-3 mm2/s,上皮型(0.95±0.18)×10-3 mm2/s。结论侧脑室脑膜瘤具有一定的MRI征象,可以提高术前诊断的准确性。

Objective To study the magnetic resonance imaging features of the ventricular meningioma .Methods Mag-netic resonance imaging features of 27 patients with pathologically proved ventricular meningiomas were retrospectively an-alysed .Results 25 cases lay in posterior horn and trigone of lateral ventricle （19 cases in left ,6 cases in right） ,1 case lay in central part of lateral ventricle ,1 case was multiple .All tumours appeared as well-demarcated masses in the lateral ven-tricle at MRI .The tumour shape was round in 22 cases （81% ） and lobulated in 5 cases （19% ） including 1 case having deep lobulated .Masses were isointense or hypointense to grey matter on T1-weighted images and mildly hyperintense , isointense on T2-weighted and fluid-attenuated inversion recovery （FLAIR） images ,it had the signal with meningomas out of brain ventricle .The most masses were marked enhancement and can be displayed the edge of tumor associated with cho-roid plexus .The pathological subtype of the 19 meningiomas was fibromatous with ADC value （mean 0 .89 ± 0 .12×10-3 mm2/s） ,8 meningiomas were Meningothelial with ADC value（mean 0 .95 ± 0 .18× 10-3 mm2/s） .Conclusion There are some rather characteristic MRI features in lateral ventricular meningioma ,which are very helpful in preoperative diagnosis .