胚胎发育不良性神经上皮瘤的MRI表现与病理对照分析

目的:分析6例胚胎发育不良性神经上皮瘤(dysembryoplastic neuroepithelial tumors,DNT)的MRI表现和病理所见,探讨其MRI表现特征与病理间的关系。方法:回顾性分析6例经手术病理证实的DNT的MRI资料和病理所见,观察MRI信号改变与病理所见的关系。结果:典型的DNT位于皮层或主要位于皮层区,肿瘤以囊性成分为主,病灶在T1WI为低信号,T2WI为高信号,其ADC值增高,FLAIR序列上病灶边缘和分隔为高信号改变,增强扫描病灶实质结节或分隔可见轻度强化。瘤周无水肿,三角征和瘤内分隔为其影像学表现特征。与之病理对照所见DNT肿瘤细胞弥漫分布、密度不高、胞浆较空、存在黏液湖及肿瘤内富含薄璧分枝状血管是形成MRI所见的组织学基础。结论:DNT的MRI所见具有特征性,反映了其组织病理学改变特征,在病理诊断困难的情况下,结合临床和影像学表现,可以对DNT做出正确的诊断。

Dysembryoplastic neuroepithelial tumors: the correlation of MRI findings and histopathology

Objective:Analysis the findings of dysembryoplastic neuroepithelial tumors(DNTs) on MR and pathology studies,and to compare the correlation of MRI finding with pathology.Methods:We analyzed the MR images of 6 patients who diagnosed DNT with respect to tumor location,size,MR signal intensity,mass effect,contrast enhancement,heterogeneity and compared these features with pathologic findings.Results:Typical DNT was located in cortical or subcortical white matter,with cystic or semiliquid structures.On MR images appeared as lesions with inhomogeneous signal intensities,consistent MR feature in all cases were the presence of one or multiple areas of moderately or markedly reduced T_1-signal and markedly or moderately increased T_2-signal,with moderate enhancement.The presence of "septations",triangular pattern of distribution,and absence peritumour edema was the features of DNT.In histopathology,the lesion consist of many oligodendroglia-like cells with small round nuclei and a clear perinuclear halo,located in a myxoid matrix with many small capillaries.Conclusion:The MR characteristic feature of DNT corresponds its architecture.Radiologic examination may be helpful for the diagnosis of DNT when pathologic findings are inconclusive.