Drape J L, Krause D, Tongio J
Service de Radiologie III, Hôpital de Hautepierre, Strasbourg, France.
J Neuroradiol. 1992;19(1):49-62.
The authors have attempted to establish by MRI morphological criteria for the so-called "aggressive" intracranial meningiomas. The MRI features of 20 meningiomas histologically aggressive (numerous mitoses and small necrotic foci) or malignant (same plus invasion of the subjacent brain tissue) were compared with those of a control population of 26 patients with benign meningioma. The site of the tumour and its histological type had little predictive value, but there was a remarkably high proportion of male patients in the group with aggressive meningioma (9/20 versus 2/26). More than other varieties, aggressive meningiomas frequently emitted, on both T1- and T2-weighted sequences, a heterogeneous signal due to a necrotic focus (P less than 0.01). The high-intensity signal observed on T2-weighted sequences (11/20) was suggestive of syncitial or angioblastic meningioma. Cystic meningiomas were present in virtually equal proportions (3/20 versus 3/26) in the two populations and could raise problems concerning the diagnosis of nature, especially when intraventricular. Gadolinium injection provided further evidence of aggressiveness, such as irregular tumour outline or even contrast enhancement of brain tissue in malignant cases (3/4), but enhancement of the dura mater was equally frequent in both groups (P greater than 0.2). Massive peritumoral oedema was significantly more frequent in aggressive melanomas (P less than 0.01).
作者试图通过MRI形态学标准来确定所谓“侵袭性”颅内脑膜瘤。将20例组织学上具有侵袭性（大量核分裂象和小坏死灶）或恶性（上述表现加侵犯邻近脑组织）的脑膜瘤的MRI特征与26例良性脑膜瘤患者的对照组进行比较。肿瘤部位及其组织学类型的预测价值不大，但侵袭性脑膜瘤组男性患者比例显著较高（9/20对2/26）。与其他类型相比，侵袭性脑膜瘤在T1加权和T2加权序列上更常因坏死灶而发出不均匀信号（P<0.01）。T2加权序列上观察到的高强度信号（11/20）提示为合体细胞型或血管母细胞型脑膜瘤。两组中囊性脑膜瘤的比例几乎相等（3/20对3/26），这可能会给性质诊断带来问题，尤其是当肿瘤位于脑室内时。注射钆剂进一步证明了侵袭性，如肿瘤轮廓不规则，甚至在恶性病例中脑组织有对比增强（3/4），但两组中硬脑膜增强同样常见（P>0.2）。侵袭性脑膜瘤中瘤周大量水肿明显更常见（P<0.01）。
