摘要
目的评价磁共振扩散张量成像(DTI)在诊断中枢系统疾病中的用途。方法 86例临床证实的中枢神经系统疾病患者包括超急性及急性期脑梗死40例,脑肿瘤32例,脑白质疏松7例,多发性硬化4例,脑中毒3例以及作为正常对照的健康志愿者9例均经常规磁共振序列和DWI、DTI检查,对患侧和健侧大脑白质纤维束感兴趣区各向异性分数(FA)值进行定量分析,获得方向编码彩色(DEC)图和黑白各向异性(FA)图,扩散张量纤维束成像(DTI)显示脑白质纤维束走形方向、损伤、受压、移位等情况。结果健康组不同部位的脑白质的FA值不同,但大脑半球两侧的FA值差异无统计学意义。超急性(发病后小于6 h)脑梗死区白质FA值与对侧相比轻度增高或降低,急性期(发病后6～72 h)脑梗死区白质FA值显著减低,FA图为低信号,健侧脑白质为高信号,均有明显差别。良恶性脑肿瘤FA值仅在瘤周水肿区的比较中有统计学差异,FA图肿瘤实质为稍低信号,中心坏死及周围水肿表现为低信号。脑白质病变和正常对照组感兴趣区测量FA值,病变区FA值降低,两组差异有统计学意义。结论 DTI可无创且清晰地显示白质纤维束走行方向及分布情况,对诊断中枢神经系统病变有重要用途。
Objective To evaluate the utility of diffusion tensor imaging（DTI） in the diagnosis of central nervous system diseases （CNSD）.Methods Eighty-six patients with clinically proved CNSD which comprised acute-and superacute cerebral infarcts（n=40）,brain tumors（n=32）,cerebral white matter rarefaction（n=7）,brain multiple scleroses（n=4）,and brain toxis（n=3） underwent conventional MR T_1WI,T_2WI,diffusion weighted imaging（DWI）,and diffusion tensor imaging（DTI）.Nine healthy volunteers with matching age and sex were taken as normal controls.The fractional anisotropy（FA） values in the areas of interest（AOI） of cerebral white matter fibre bundles between affected side and intact side or normal control were quantitatively analyzed by using DTI acquired from direction encode color（DEC） and black-white anisotropy picture to visualize the walking direction,injury,compression and displacement of cerebral white matter fibre bundles. Results The FA values of cerebral white matter in normal controls were different with various locations but there were not statistic difference between bilateral cerebral hemispheres.The FA value in affected side of superacute cerebral infarct（less than 6 h after onset） was slightly higher or lower than that in intact side.The FA value in affected side of acute cerebral infarct（6-72 h after onset） was significantly decreased and the FA picture showed hypointensity but that in intact side was hyperintensity and there was significant difference between both sides.The FA values in peritumoral edema areas between benign-and malignant tumors were statistic differences.On FA pictures, tumoral parenchyma appeared as slight hypointensity,while tumoral center necrosis and peritumoral edoma areas appeared as hypointensity. Compared with normal controls,the FA value in AOI of cerebral white matter lesions was decreased and there was statistic difference between both groups.Conclusion DTI can non-invasively and clearly show the walking direction and distribution state of cerebral white matter fibre bundles,and thus it plays important role in the diagnosis of CNSD.
出处
《实用医学影像杂志》
2011年第1期4-7,共4页
Journal of Practical Medical Imaging
关键词
中枢神经系统疾病
磁共振成像
扩散张量
各向异性分数
Central nervous system
Magnetic resonance imaging
diffusion tensor
Anisotropy fraction
