胚胎发育不良性神经上皮瘤的CT和MRI表现特征

目的 分析胚胎发育不良性神经上皮瘤(DNT)的CT和MRI表现特征,以提高该病的诊断准确性.方法 对经手术病理证实的10例DNT的CT和MR材料进行回顾性分析.结果 10例均位于幕上,局限于皮层或以皮层为主,呈类圆形、分叶状、楔形或不规则状假囊肿样.T_1WI呈低信号,T_2WI呈高信号,FLAIR像见完整或不完整高信号"环征"及分隔,其他部分呈等偏低信号,DWI上呈低或等偏低信号,波谱表现NAA轻度降低.增强后7例病变无强化,3例病变内呈轻度不均匀强化,无病变周围水肿及占位效应,病灶边界大部分清晰,其中1例病灶无明显边界.2例CT扫描病变均呈低密度改变,其中1例病灶内有条状钙化.结论 DNT在影像学上表现较具特征性,有助于术前正确诊断.

CT and MR Imaging Features of Dysembryoplastic Neuroepithelial Tumor

Objective To analyze CT and MR imaging features of dysembryoplastic neuroepithelial tumor(DNT),so that to improve its diagnostic accuracy.Methods CT and MRI fidnings of DNT in 10 cases proved surgically and pathologically were retrospectively reviewed.Results All lesions were located in the super-tentorial gray matter regions or involved the cererbral certex mainly.The lesions were round,lobular,triangular or irregular pseudocystic masses with definite borders mostly.The lesions were hypointense on T_1WI and hyperintense on T_2WI.On fluid attenuated inversion recovery weighted images,the hyperintense "ring sign" and septa of the lesions were seen.On diffuse-weighted images(DWI),the lesions were hypointense or slight hypointense.On MR spectroscopy,NAA of the lesions slightly decreased.There were no peripheral edema and mass effect with well-demarcated.7 lesions had no enhancement and 3 lesions had slight unhomogeneous enhancement after administration of contrast medium.The lesions in 2 cases on plain CT showed low attenuation and one had calcification inside the lesion.Conclusion DNTs are of typical neuroradiologic features,that may be helpful for the diagnosis of which preoperatively.