脑内胚胎发育不良性神经上皮瘤与低级别星形细胞瘤的MRI比较研究  

Comparative study of dysembryoplastic neuroepithelial tumor and low grade astrocytoma on MRI

作　　者：武春雪[1] 高培毅[1] 

机构地区：[1]首都医科大学北京市神经外科研究所,北京100050

出　　处：《放射学实践》2012年第3期279-283,共5页Radiologic Practice

摘　　要：目的:探讨脑内胚胎发育不良神经上皮瘤(DNET)与幕上皮层下低级别星形细胞瘤的MRI影像表现对鉴别两种疾病的价值。方法:经病理证实的DNET 35例及低级别星形细胞瘤33例,分别对2组患者的年龄、性别及各种MRI表现(采用评分法)进行分析,采用两独立样本的Mann-Whitney U检验及Logistic回归分析,获得诊断DNET的回归方程。由一位高年资及一位低年资神经放射医师在数据分析前后分别对两组患者进行阅片,分析其诊断准确性及两次的变化。结果:DNET组平均年龄为(19.09±1.95)岁,明显低于低级别星型细胞瘤组的(32.58±2.32)岁,差异有极显著性意义(P<0.01,Z=-4.09);两组患者性别差异无统计学意义(P=0.35,Z=-0.93);DNET组病变最大径为(3.57±0.25)cm,低级别胶质瘤组为(4.28±0.30)cm,两者间差异无统计学意义(P=0.07,t=-1.84);DNET组病变表现为多囊或脑回样结构、三角征、边界清晰、T2WI信号较高、瘤内分隔、无瘤周水肿或占位效应等征象的例数(分值分别为32、16、33、45、14和0)均高于低级别星形细胞瘤组(分值为12、3、20、65、1和10),差异均有显著性意义(Z=-4.71～-1.62,P均<0.05);而低级别星形细胞瘤出现明显强化者(18分)要多于DNET(3分),差异有极显著性意义(P<0.01,Z=-2.08)。Logistic回归分析结果显示年龄、形态、三角征、边界、T2WI信号、瘤周水肿或占位效应这6个变量进入回归方程(P值均<0.05)。了解这些数据后高年资及低年资医师的诊断符合率(分别为87.1%和82.9%)均高于了解前(分别为77.1%和65.7%),其中低年资医师的提高有统计学意义(P=0.01,Z=2.95)。结论:DNET与低级别星形细胞瘤的MRI影像鉴别诊断诸多因素中,当患者年龄较小(<24.5岁)、病变可观察到多囊或脑回样结构、可见三角征、边界清晰、T2WI呈高信号以及无瘤周水肿或占位效应时,诊断更倾向于DNET,综合分析这些因素将有助于提高DNET诊断的准确性。Objective：To investigate the value of MR imaging features in distinguishing DNETs and low grade astrocytomas.Methods：A retrospective analysis was performed in 35 cases of DNET and 33 cases of low grade astrocytoma which were histologically proved.The data including age,sex and MRI features were evaluated by non-parameter test and logistic regression analysis in SPSS 13.0,and non-numerical variables were assigned.The images of all cases were reviewed independently by 2 neuroradiologists in two different grades before and after the study,and Z test were conducted twice to analyze the diagnostic accuracy and the improvement respectively.Results：The average age of DNETs（19.09±1.95） was significant lower than that of low grade astrocytomas（32.58±2.32）,P0.01,Z=-4.09.There were no significant differences of sex and longest diameter between DNETs and low grade astrocytomas（P=0.30 and 0.07,Z=-0.93,t=-1.84,respectively）.The gyriform structure or multiple cysts（32）,＂triangle sign＂（16）,well defined margin（33）,high signal intensity on T2WI（45）,intratumoral septum（14）,no peritumoral edema or space occupying effect（0） were mostly seen in DNETs than those in low grade astrocytomas（12,3,20,65,1 and 10,respectively） on MRI（P0.05）.And low grade astrocytomas got significantly higher scores on ＂enhancement＂（18） than DNETs（3）（P0.01,Z=-2.08）.Actually,by logistic regression equation,the age,gyriform structure or multiple cysts in tumor,＂triangle sign＂、well-defined margin、signal intenstiy high on T2WI、no peritumoral edema or no space occupying effect were the most significant parameters between DNETs and low grade astrocytomas（P0.05）.Diagnostic accuracy of DNET was improved more or less in the second film reading after combining the signs above.The accuracy of 65.7%was increased dramatically in the low grade doctors by up to 82.9%（P0.01,Z=2.95）.Conclusion：The age less than 24.5 years old,gyriform structure or multiple cysts in tumor,＂triangle si

关 键 词：脑肿瘤 胚胎发育不良性神经上皮肿瘤 星形细胞瘤 磁共振成像 

分 类 号：R739.41[医药卫生—肿瘤] R445.2[医药卫生—临床医学]