胚胎发育不良性神经上皮肿瘤的MRI表现

MRI findings of dysembryoplastic neuroepithelial tumor

目的总结8例胚胎发育不良性神经上皮肿瘤(DNET)的MRI表现,以提高对此病的认识。方法回顾性分析经手术病理证实的8例DNET,总结其影像特点。结果 8例肿瘤累及脑皮层,边界清楚,无瘤周水肿及占位效应,位于颞叶4例,枕叶2例,额叶1例,小脑1例。5例具"三角征",4例具"分隔征",3例呈单或多囊性。肿瘤T1WI呈低信号,T2WI呈高信号,增强后4例无强化,4例呈线状、分隔状、小结节状强化。7例FLAIR像可见肿瘤周边稍高信号"环征"。结论 DNET的MRI表现有一定特征性,MRI对于肿瘤的术前准确诊断有重要意义。

Objective To summarize the MRI manifestations of eight cases of dysembryoplastic neuroepithelial tumors（DNET）so as to improve awareness of the disease.Methods We retrospectively analyzed eight cases of DNET,which were confirmed pathologically and summarized their imaging characteristics.Results 8cases of DNET were involved the cerebral cortex,which presented with clear boundary and were devoided of peritumoral edema or mass effectiveness.Of these 8cases,4cases were locted in the temporal lobe,2cases in occipital lobe,1case in frontal lobe,and 1case in cerebellum.5cases presented with the ＂triangle sign＂,4cases had ＂separated＂ sign,and 3cases were shown to be a single or multiple cystic.Tumors were hypointensity on T1 WI and hyperintensity on T2 WI.After contrast enhancement,4cases were shown no enhancement,4cases were shown to be linear,separated shape,and small nodular enhancement.On T2-FLAIR,7cases appeared visible signal ＂ring sign＂ in the tumor periphery.Conclusion The MRI findings of DNET have certain characteristics of imaging findings,which are important for accurate diagnosis of tumors before surgery.