致痫性神经上皮肿瘤的磁共振成像及临床病理对照

MR Imaging Findings of Epilepsy-associated Neuroepithelial Neoplasms with Clinico-pathological Correlation

目的:分析致痫性神经上皮脑肿瘤的MRI、PET及临床病理资料,提高对该类肿瘤的诊断水平。方法:本组共31例,病理诊断胚胎发育不良性神经上皮肿瘤(DNT)13例,节细胞胶质瘤或节细胞瘤(GG)7例,复合性胶质神经元肿瘤2例,中枢神经细胞瘤1例,星形胶质细胞瘤8例。临床均以癫痫为首发症状。患者术前均行脑部磁共振检查,9例行PET或CT检查。影像分析病灶部位、大小、形态、信号(密度)特点和病灶周围水肿、占位效应及增强后表现。结果:病灶多位于颞叶和额叶皮质或皮质下,发病年龄以青年为主,病灶多呈圆形或类圆形。DNT以假囊状或小泡状长T2信号,无强化或点状、小结节状强化为特点,4例18F-FDG-PET检查均为低代谢。节细胞瘤或节细胞胶质瘤表现为囊实性、囊性或实性,病灶内钙化占62.5%,无灶周水肿或轻度灶周水肿,增强扫描后呈结节、斑块状不均匀强化。2例18F-FDG-PET显示病灶内有结节状高代谢,2例呈低代谢。结论:致痫性肿瘤多以神经元和混合性胶质神经元肿瘤和低级别胶质星形细胞瘤为多见,MRI有助于上述肿瘤的诊断和鉴别诊断。

Objective： To analyze MRI findings as well as PET and clinicopathologic features of epilepsy-associated neuroepithelial neoplasms.Methods：Thirty-one patients confirmed pathologically with dysembryoplastic neuroepithelial tumors（DNT,13 cases）,astrocytomas and oligodendroglioma（8 cases）,ganglio-cytomas/ganglioglioma（GG,7 cases）,mixed neuronal gliomas（2 cases） and centra neurocytoma（1 case） were involved.Seizure was the first symptom in all patients.All cases were subjected to MRI examination before surgery.Meanwhile,9 cases received PET/CT examination.The images were studied with regard to location,size,margin,signal intensity,enhancement characteristics.Clinical data,such as presenting signs and symptoms,physical findings,and medical histories,were collected.Results：Most lesions were located in cortex and subcortex of temporal and frontal lobe.The MRI features of DNT were cystic or alveolar lesions with long T2 signals and nonenhancement or small nodular enhancement.18F-FDG-PET showed the lesions with low metabolism in 4 cases.Gangliocytoma or gangliogliomas showed cystic,cystic-solid and solid lesions with or without edema and with nodular and patching-like enhancement.Calcification was found in 62.5% patients.Two of them showed nodular high metabolism and the other two showed low metabolism on 18F-FDG-PET.Conclusion：Neuronal and mixed neuronal-glial tumors and lower grade astrocytic tumors are the most common tumors in epilepsy-associated neoplasmas.MRI is useful in diagnosis and differential diagnosis of these tumors.