脑梗死患者与正常成人扩散张量成像的对照研究

目的探讨扩散张量成像技术(DTI)在脑梗死患者中对病变侧与对侧脑不同部位的部分各向异性值(FA)和平均扩散系数(ADC)的检测价值。方法对17例脑梗死患者(梗死组)和8名正常成人(正常对照组)进行常规MRI和DTI检查,分别测量半卵圆中心、侧脑室后角旁、内囊前肢、膝部、后肢、豆状核、胼胝体膝部、压部及梗死灶中心感兴趣区的FA、ADC值。结果正常对照组左右侧FA、ADC值比较差异均无统计学意义(均P>0.05)。梗死组病变侧与"正常侧"不同部位FA比较,除梗死灶中心、内囊后肢之间差异有统计学意义(均P<0.05),余各个部位FA之间差异均无统计学意义(均P>0.05)。梗死组病变侧与"正常侧"不同部位ADC比较,梗死灶中心与对侧ADC之间差异有统计学意义(P<0.05),余各个部位ADC之间差异无统计学意义(均P>0.05)。正常组与梗死组"正常侧"不同部位FA、ADC比较,侧脑室后角旁、内囊膝部FA之间差异均有统计学意义(均P<0.05),侧脑室后角旁ADC之间差异有统计学意义(P<0.01)。结论梗死侧的对侧镜像区并不是通常所认为的"正常侧"。对脑梗死进行定量研究时,不能简单地以对侧镜像区为参照,而应该以大样本的志愿者建立正常对照的标准。

Diffusion tensor imaging in patients with cerebral infarction and healthy adults

Objective To study whether and value of cerebral regions is significant different between the infarction side and contralateral hemisphere of cerebral infarction by diffusion tensor imaging (DTI). Methods Seventeen patients with cerebral infarction (infarction group) and 8 healthy adults (control group) underwent conventional plain MRI scan and DTI examination with Siemens Trio 3.0T super-conducting MRI system. Fractional anisotropy (FA) and average diffusion coefficient (ADC) value of regions of interest (ROI) were measured on axial FA map,including centrum semiovale,white matter close to occipital angle of ventricle,anterior limb,genu and posterior limb of internal capsule,lentiform neucleus,genu and splenium of corpus callosum as well as infarction regions. Results There was no statistically significant difference in FA and ADC value of all cerebral regions between both sides in control group. FA value of cerebral regions in infarction side and "normal hemisphere" of infarction had no statistically significant difference but infarction regions and posterior limb of internal capsule. ADC value of cerebral regions in infarction side and "normal hemisphere" of infarction had no statistically significant difference but infarction regions. FA of white matter close to occipital angle of ventricle,genu of internal capsule and ADC of white matter close to occipital angle of ventricle had statistically significant difference between control group and "normal hemisphere" of infarction group. Conclusion The DTI results indicate that contralateral hemisphere of cerebral infarction is not normal,which can not be as reference side when cerebral infarction is quantitative analyzed.