健康成人豆状核弥散特性与铁含量的相关性

Correlation between diffusion properties and iron deposition of lenticular nucleus in healthy adults

目的探讨脑正常老化过程中豆状核的弥散特性与铁含量的相关性。方法对124名右利手健康志愿者行脑DTI与SWI,测量壳核和苍白球FA、平均扩散率(MD)、本征值(λ1、λ2、λ3)及Phase值;应用SWI测量30岁以上志愿者额叶白质、尾状核头、壳核、苍白球、丘脑、红核、黑质的Phase值,分析Phase值与铁含量的相关性;比较壳核与苍白球之间上述各指标的差异;分析壳核和苍白球上述各指标与年龄的相关性及各弥散参数与Phase值的相关性。结果 Phase值与铁含量呈负相关(r=-0.837,P=0.019)。壳核FA、MD、λ1和λ2低于苍白球,λ3和Phase值高于苍白球,差异均有统计学意义(P均<0.001)。壳核各弥散参数均与年龄呈正相关(P均<0.05),Phase值与年龄呈负相关(P均<0.001);苍白球MD、λ1、λ2和λ3与年龄呈正相关(P均<0.001),FA和Phase值与年龄无相关性(P均>0.05)。左侧壳核FA和λ1,右侧壳核FA、λ1和MD与Phase值呈负相关(P均<0.01);双侧苍白球各弥散参数与Phase值均无相关性(P均>0.01)。结论壳核与苍白球之间弥散参数及铁含量存在差异,双侧壳核FA、λ1及右侧壳核MD与铁含量呈正相关。

Objective To explore the correlation between diffusion properties and iron deposition in the lenticular nucleus during brain aging. Methods Totally 124 right-handed healthy volunteers underwent DTI of brain to obtain FA, mean diffusivity （MD）, λ1, λ2 and λ3 of the putamen and globus pallidus. Phase values of the frontal white matter, caput nucleus caudate, putamen, globus pallidus, thalamus, red nucleus, substantia nigra were measured with SWI, and the correlation between Phase value and iron concentration was analyzed. The above indexes were compared between putamen and globus pallidus, and the correlations of these indexes with age were analyzed. In addition, the relationship of diffusion parameters and Phase value was analyzed. Results Phase value significantly negatively correlated with iron concentration of postmortem brain （r=-0.837, P=0.019）. FA, MD, λ1, λ2 were lower and λ3, phase value was higher in the putamen than those in the globus pallidus （all P〈0.001）. In the putamen, all the diffusion parameters were positively and Phase value was negatively correlated with aging （all P〈0.05）. In the globus pallidus, MD, λ1, λ2 and λ3 were positively correlated with aging （all P〈0.001）, while FA and Phase value had no significant linear correlation with age （all P〉0.05）. FA, λ1 in the left putamen and FA, λ1, MD in the right putamen were negatively correlated with Phase value （all P〈0.01）, while all the diffusion parameters in the globus pallidus had no correlation with Phase value （all P〉0.01）. Conclusion There are differences of diffusion parameters and Phase value between putamen and globus pallidus. FA, λ1 in both sides and MD in the right side of the putamen are positively correlated with iron concentration.