髄膜腫におけるMRI腫瘍周囲異常信号域の検討

Perifocal Abnormal Signal Intensity Area in MRI in Meningiomas

I．はじめに

　髄膜腫のX線CT像における周囲低吸収域の本態は脳浮腫という報告　^4,5,9,20），CSF spaceとの報告^{4,5,11,17,18）}，腫瘍表面の血管^21），壊死^17），あるいはその複合であるとの種々の報告があり，その本態，発生機序については未解決な点が多い．そこでわれわれは髄膜腫のX線CT像とMRIを検討して以下の結果を得た．

To investigate the perifocal abnormal signal intensity area in MRI in meningiomas, we have analysed MRI in 10 cases among 73 meningiomas which were diagnosed by X-ray CT and verified by operation and pathology.

The MRI scanners used in this study were Siemens Magnetom and Toshiba MRT 15A. Ten meningiomas diagnosed by MRI were as follows ; one free convex-ity, one pyramidal, three falx and parasagittal, one sphenoid ridge, one olfactory groove, one cerebello-pontine angle, two ventricular meningiomas. Perifocal abnormal signal intensity area was diagnosed as vasogenic edema in 4 cases.