阿尔茨海默病患者联络纤维的DTI诊断价值

Association Fibers Integrity in Alzheimer's Disease

目的采用磁共振扩散张量成像(diffusion tensor imaging,DTI)观察阿尔茨海默病(Alzheimer’s disease,AD)患者联络纤维的改变情况。资料与方法对10例轻中度AD患者和18名健康老年人(对照组)行常规MRI[(T1WI、T2WI、T2液体衰减反转恢复序列(FLAIR)]及DTI检查,DTI测量双侧扣带束、上纵束Ⅱ、钩束及额枕下束8个感兴趣区(ROI)的部分各向异性分数(FA)值。采用简易精神状态量表(MMSE)和蒙特利尔认知评估量表(MoCA)对AD患者的认知功能进行测定。结果与对照组相比,AD组MMSE评分和MoCA评分较对照组明显下降(P<0.05),AD组常规MRI上ROI白质信号无明显变化,ROI部位的FA值均显著下降(P<0.05),且上纵束Ⅱ的FA值与MMSE(右侧r=0.672,P=0.033,左侧r=0.919,P<0.01)和MoCA(右侧r=0,747,P=0.013;左侧r=0.679,P=0.031)评分呈正相关。结论轻中度AD患者存在联络纤维损害且上纵束Ⅱ的损害程度与认知功能密切相关。

Objective To evaluate the association fibers integrity in patients with Alzheimer＇s Disease（AD） measured by fractional anisotrophy（FA） using diffusion tensor imaging（DTI）.Materials and Methods Magnetic Resonance Imaging（T1WI,T2WI,as well as T2 fluid attenuated inversion recovery FLAIR） and DTI were performed on 10 mild to moderate AD patients and 18 healthy volunteers.FA values which were post-processed from DTI in 8 regions of interests（ROIs） including the bilateral posterior cingulum,superior longitudinal fasciculus II,uncinate fasciculus and inferior fronto-occipital fasciculus were measured and compared between the two groups.MMSE and MoCA were administrated to evaluate the cognitive function.Results All the AD patients and controls showed no abnormal signals on both T1 weighted and T2-weighted images.Compared to the controls,the FA values in all the selected ROIs,as well as the MMSE and the MoCA scores in AD were significantly decreased（P0.05）.In addition,the decreased FA values in the SLF II positively correlated with the scores of MMSE（right r=0.672,P=0.033,left r=0.919,P0.01） and MoCA（right r=0.747,P=0.013,left r=0.679,P=0.031）.Conclusion Abnormality of the white matter integrity in association fibers can be observed in patients with AD and the decreased FA values in the SLF II significantly correlated with the cognitive function.