摘要目的 探讨胚胎发育不良性神经上皮瘤(DNT)的磁共振(MRI)影像特点,提高对DNT的诊断.方法 收集经手术病理证实的10例DNT患儿临床资料,回顾性分析其影像学表现及临床特点.结果 10例患者中,9例位于幕上大脑半球皮质,颞叶3例,额叶5例,顶叶1例,其中2例累及皮质下白质.MRI平扫,9例幕上肿瘤中,T1加权成像(T1WI)呈低信号8例,等低混杂信号1例,T2加权成像(T2WI)呈高信号9例,液体衰减反转恢复序列(FLAIR)呈稍高信号9例.肿瘤表现为囊性或以囊性部分为主,部分瘤内见分隔.3例周围高信号“环征”及瘤内分隔,2例表现为“三角征”,3例表现为“脑回征”,1例表现为类圆形病灶,类似囊肿.肿瘤均无明显瘤周水肿及占位效应,增强扫描仅l例有轻度不均匀强化,余6例未见强化.1例肿瘤位于小脑半球,表现为囊实性肿块,实性部分T1WI呈低信号、T2WI呈高信号,囊性部分T1 WI呈低信号、T2WI呈高信号.壁结节较明显强化,囊壁轻度强化,囊性部分未见强化.可见瘤周水肿及占位效应.10例肿瘤中均未见出血及钙化.结论 DNT的MRI表现有一定特征性,有助于术前正确诊断.

abstractsObjective To study magnetic resonance imaging(MRI) features of dysembryoplastic neuroepithelial tumor(DNT) and to improve accurate diagnosis of DNT.Methods The MRI appearance and clinical features of 10 patients with DNT confirmed by surgery and pathology were analyzed retrospectively.Results In 10 cases,9 tumors located in supratentorial hemisphere cortex,3 tumors located in the temporal lobe,5 in the frontal lobe,1 in the parietal lobe,and 2 of them encroached the adjacent white matter.In 9 tumors located in supratentorial hemisphere cortex,8 cases had decreased signal intensity on T1-weighted MR images,1 case iso-decreased mixed signal intensity on T1-weighted MR images,and 9 cases increased signal intensity on T2-weighted images,9 cases slightly increased signal intensity on fluid attenuated inversion recovery weighted images.The manifestation of tumors was cystic or cystic partially oriented and was seen separate section intratumoral in some cases.Three cases appeared as hyperintense" ring sign" and internal septation,2 cases appeared as a triangle in shape,3 cases appeared as gyms-like shape,and 1 case as round shape,similar to cyst.Nine tumors had no significant mass effect and peritumoral edema.Enhanced MR imaging showed only 1 case with slight and heterogeneous enhancement,the rest 6 cases showed non enhancement.One case located in cerebellar hemisphere,and appeared cystic-solid mass,the solid part had decreased signal intensity on T1-weighted MR images,and increased signal intensity on T2-weighted images,the cystic part had decreased signal intensity on T1-weighted MR images,and increased signal intensity on T2-weighted images.On enhanced MR imaging,the wall-node obviously contrast enhancement,cyst wall slightly contrast enhancement,cystic part non enhancement.The tumor had peritumoral edema and mass effect.Ten cases had no hemorrhage and calcification.Conclusion The MRI appearance of DNT is characteristic and is helpful for the preoperative diagnosis of DNT.