摘要
目的探讨各向异性模型(MO)及常用扩散张量成像(DTI)指标对轻中度阿尔茨海默病(AD)脑白质纤维损伤的评估价值。方法前瞻性收集2015年2月至2018年2月温州医科大学附属第一医院33例轻中度AD患者作为AD组,同时收集20名年龄、性别与AD组匹配的志愿者作为对照组。所有受试者均行颅脑常规MRI及DTI扫描。对DTI图像采用TBSS后处理,获得白质纤维的各向异性模型(MO)、各向异性分数(FA)、平均扩散系数(MD)、径向扩散系数(RD)、轴向扩散系数(AxD)值。AD组和对照组各DTI指标的比较在FunctionalMRISoftwareLibrary自带软件中进行。结果与对照组相比,AD组出现FA值减低、RD值升高(P<0.05)的区块数均为1,受累纤维束包括双侧丘脑前辐射、皮质脊髓束、扣带回、海马、下额枕束、下纵束、钩束、上纵束、上纵束(颞部);在P<0.05未发现MD升高或降低的白质纤维,在P<0.1发现MD升高与FA减低、RD升高的区域基本重合。发现3个基本重合的AxD值与MO值均升高区块(P<0.05),包括左侧内囊前肢、双侧内囊后肢、后钳、左侧半卵圆中心、顶叶;2个MO值减低的区块同时伴FA值减低、RD值升高(P<0.05),包括穹隆、前钳、外囊、半卵圆区、左侧额叶。结论MO与DTI常用张量指标(FA、RD、MD、AxD)的联合应用可进一步揭示AD白质纤维尤其是交叉纤维损伤情况。MO联合FA、RD、MD异常揭示交叉纤维2个分支均发生退行性变;MO联合AxD异常则揭示白质改变以交叉纤维其中1个分支的轴突损伤为主。
Objective We performed a diffusion tensor imaging (DTI) study to explore the value of mode of anisotropy (MO) and other DTI-derived indices in assessing white matter fiber damage with mild to moderate Alzheimer disease (AD) patients. Methods This study was a prospective study. From February 2015 to February 2018, 33 patients with mild to moderate AD according to criteria were prospectively recruited as AD group at the First Affiliated Hospital of Wenzhou Medical University. Twenty healthy age-, sex-matched volunteers were recruited as normoal conctrast (NC) group. All subjects were performed by conventional brain MRI and DTI scans. The MO, anisotropic fraction (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AxD) of white matter fibers were obtained from DTI images after TBSS post-processing. The statistical analyses of DTI indices between AD group and NC group were carried out in Functional MRI Software Library software. Results As compared with NC group, we found 1 cluster with significant decrease FA and increase RD in AD group, the affected fibers involving bilateral anterior thalamic radiation, corticospinal tract, cingulate gyrus, hippocampus, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, uncinated fasciculus, superior longitudinal fasciculus (P<0.05). The MD value increase(P<0.1) was found to coincide with the decrease of FA and the increase of RD, while no significant increase or decrease in P<0.05. Three clusters of MO increases (P<0.05) accompanying with increases of AxD were found in left anterior limb of internal capsule, bilateral posterior limb of internal capsule, posterior forceps, left centrum semiovale and parietal lobe. Two clusters of MO decreases (P<0.05) accompanying with decreases of FA and increases of RD were found in fornix, forceps, external capsule, centrum semiovale and left frontal lobe. Conclusions The combination of MO with DTI routine tensor indices (FA, RD, MD, AxD) can further reveal the microstructural damage of white matter
作者
闻彩云
周晓军
王溯源
王美豪
王贞
曹国全
王智廷
Wen Caiyun;Zhou Xiaojun;Wang Suyuan;Wang Meihao;Wang Zhen;Cao Guoquan;Wang Zhiting(Department of Radiology,the First Affiliated Hospital of Wenzhou Medical University,Wenzhou 325000, China;Department of Internal Neurology,the First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000,China;Department of Cardiology,the First Affiliated Hospital of Wenzhou Medical University,Wenzhou 325000,China)
出处
《中华放射学杂志》
CAS
CSCD
北大核心
2019年第2期138-144,共7页
Chinese Journal of Radiology
基金
浙江省自然科学基金(LY14H180006)
温州市科技局公益性科技计划(Y20160469,Y20160156).
