弥漫性轴索损伤患者胼胝体DTI纵向评估

目的 评价亚急性期弥漫性轴索损伤(DAI)患者胼胝体各亚区域微观结构及其短期变化.方法 连续性纳入亚急性期DAI患者21例,其中12例于1月后(31.5 d±6.2 d,28~43 d)复查,招募12例性别、年龄匹配的健康对照组,所有受试者使用3.0T磁共振仪扫描获取脑部DTI数据.在矢状位各向异性分数(FA)图将胼胝体分为6个亚区域(胼胝体膝部、体嘴部、体前部、体后部、峡部及压部)计算FA值、表观扩散系数(ADC)值,分析亚急性期和随访患者胼胝体DTI参数变化,并将亚急性期患者胼胝体各亚区域DTI参数与入院时格拉斯哥(GCS)评分做相关分析.结果 亚急性期患者整个胼胝体及所有亚区域FA值显著降低,除胼胝体体前部、体后部外其余亚区域ADC值均显著升高(P<0.05),其中胼胝体峡部FA值下降幅度最大(-12.0%).12例随访患者整个胼胝体及各亚区域FA值和ADC值变化均无统计学意义(P>0.05).亚急性期患者整个胼胝体、峡部及压部FA值与入院时GCS评分呈正相关(整个胼胝体:r=0.848,P=0.000;峡部:r=0.447,P=0.048;压部:r=0.591,P=0.006).结论 胼胝体峡部是DAI最易损伤的部位;短期内(1个月)胼胝体亚区域微观结构无显著变化;亚急性期DAI患者整个胼胝体FA值能较好反映DAI患者损伤程度.

Longitudinal DTI study of the corpus callosum in patients with diffuse axonal injury

Objective To investigate microstructure of the corpus callosum(CC) in subacute diffuse axonal injury(DAI) patients and its the longitudinal change in a short time.Methods 21 patients with subacute DAI were enrolled successively in this study,and in which 12 patients were reexamined followed-up with DTI a month later (31.5 d±6.2 d,28-43 d),and then 12 gender and age matched healthy controls were recruited.The DTI data of all subjects were acquired on at a 3.0T MRI.The CC was divided into six segments:the genu, rostral mid-body, anterior mid-body,posterior mid-body, isthmus, and splenium.ROIs were placed on each segment on color fractional anisotropy (FA) maps in the midsagittal plane manually.The FA and apparent diffusion coefficient(ADC) values of each subregion of CC were measured and compared between subacute DAI group,follow-up group and controls respectively.In addition,a related analysis between DTI parameters of each sub-region of CC and GCS on admission was done by using person correlation analysis.