胚胎发育不良性神经上皮瘤的MRI诊断与鉴别诊断(附24例分析)

MRI Diagnosis and Differential Diagnosis of Dysplastic Neuroepithelial Tumor(Analysis of 24 Cases)

目的探讨胚胎发育不良性神经上皮肿瘤的MRI诊断与鉴别诊断,以提高对该病的诊断水平。方法回顾性分析经手术病理证实的24例DNET的MRI影像学表现及临床资料,并结合相关文献复习。结果胚胎发育不良性神经上皮肿瘤患者20岁以下者占比58.33%(14/24),有癫痫发作病史占比79.17%(19/24),常见发病部位分别为额叶8例,颞叶4例,海马5例,其他部位还包括枕顶叶交界区、胼胝体、脑干和小脑。肿瘤形态以三角形和类圆形多见,且MRI不同显示方位形态不同;MRI上肿瘤可以表现为假囊性4例、微囊性8例、囊实性10例和实性2例。肿瘤均表现为不均匀长T1长T2信号,瘤内及瘤周信号不均,可伴有实性等信号或假囊性长T1稍长T2信号或囊性长T1长T2信号;MRI增强多表现为无强化13例和轻度线样强化5例,可见结节样不同程度强化或脑回样/环形强化。"倒三角征"和T2FLAIR"环征"、微囊性信号是DNET特征性MRI表现。结论DNET临床特点和MRI影像表现具有一定的特征性,熟悉DNET的临床特征及MRI影像学表现有助于提高对该病的诊断水平。

Objective To investigate the diagnosis and differential diagnosis of dysembryoplastic neuroepithelial tumors in MRI to improve the diagnostic level of the disease.Methods The MRI findings and clinical data about 24 cases of DNET confirmed by operation and pathology were retrospectively analyzed,combined with related literature review.Results The proportion of dysembryoplastic neuroepithelial tumors within 20 years old accounted for 58.33%(14/24).The history of epileptic seizures was 79.17%(19/24).The typical locations of the disease were frontal lobe(8 cases),temporal lobe(4 cases),hippocampus(5 cases),Others still include the occipital parietal junction,corpus callosum,brainstem and cerebellum.The most common form of tumor is the triangle,and oval,and the shape is different in different scanning orientations of MRI.In MRI,the tumors may show pseudocyst(4 cases),microcyst(8 cases),cystic and solid(10 cases),and solid nodule(2 cases).All tumors are a low signal on T1 WI,and a high signal on T2 WI,and signal is inhomogeneity inside and around the tumor.Solid nodule(equal signal on T1 WI and equal signal on T2 WI),pseudocyst like signal(slightly low signal on T1 WI and slightly high signal on T2 WI),and cystic signal(low signal on T1 WI and high signal on T2 WI)can be seen in the tumor.No enhancement or mild linear enhancement is common on contrast-enhanced MRI of dysembryoplastic neuroepithelial tumors,and nodular enhancement of Different degree or gyrus/ring-like enhancement are occasionally found."inverted trigonometry sign","ring sign"on T2 FLAIR and microcystic signal are characteristic MRI findings of dysembryoplastic neuroepithelial tumors.Conclusion There are specific characteristics in clinical features and MRI finding of dysembryoplastic neuroepithelial tumor.Familiarity with the clinical features and MRI findings of DNET helps improve the diagnostic level of the disease.