脑白质疏松症伴轻度认知损害患者静息态功能磁共振成像研究

目的采用f MRI研究脑白质疏松症伴或不伴轻度认知损害患者静息态脑网络功能连接,探讨静息态fMRI对脑白质疏松症的早期诊断价值。方法共49例脑白质疏松症患者根据临床痴呆评价量表评分分为脑白质疏松症伴轻度认知损害组(LA-MCI组,34例)和脑白质疏松症不伴轻度认知损害组(LA-NMCI组,15例),采用简易智能状态检查量表、蒙特利尔认知评价量表、汉密尔顿抑郁量表17项和汉密尔顿焦虑量表14项评价认知功能、抑郁和焦虑症状,静息态f MRI研究脑网络功能连接。结果LA-MCI组患者年龄大于正常对照组(P=0.003),MMSE(P=0.001,0.000)和Mo CA(P=0.001,0.000)评分高于LA-NMCI组和正常对照组。与正常对照组相比,LA-MCI组患者突显网络内部核团功能连接减弱,突显网络对脑默认网络核团的功能连接呈增强趋势、对中央执行网络的功能连接呈减弱趋势;LA-NMCI组患者突显网络内部核团功能连接减弱,突显网络对脑默认网络核团的功能连接呈增强趋势、对中央执行网络核团的功能连接呈减弱趋势。结论脑白质疏松症伴或不伴轻度认知损害患者静息态激活脑区与正常人群存在差异,可以在一定程度上解释脑白质疏松症伴认知功能障碍的病理生理学机制。     

DTI评价轻度认知障碍及轻中度阿尔茨海默病脑白质微细结构损害的研究

目的应用磁共振弥散张量成像(DTI)技术研究轻度认知障碍(MCI)及轻中度阿尔茨海默病(AD)患者脑白质微细结构的改变。方法对MCI患者、轻中度AD患者各12例及健康老年人12名(对照组)行常规MRI及DTI检查,测量其胼胝体压部、额叶、顶叶、颞叶、枕叶、内囊前肢及内囊后肢白质区部分各向异性分数(FA)和平均弥散率(MD)。将3组的FA、MD值进行比较,并与MMSE评分、单词回忆及单词再认评分进行相关性分析。结果 (1)MCI患者顶叶白质FA值为0.489±0.079,与对照组(0.558±0.079)相比下降(P0.05)。(2)AD患者额叶、顶叶及颞叶FA值分别为0.405±0.072、0.454±0.069和0.363±0.056,与对照组(分别为0.499±0.081、0.558±0.079和0.440±0.061)比较差异均有统计学意义(P0.05)。AD患者胼胝体压部、额叶及顶叶MD值分别为0.978±0.082、0.920±0.054和0.81 7±0.045,均高于对照组(分别为0.801±0.093、0.820±0.084、0.712±0.096)(P0.05)。AD、MCI两组内囊前、后肢及枕叶FA及MD值分别与健康对照组比较均无统计学差异(P0.05)。(3)3组顶叶、颞叶FA值与MMSE、单词回忆及单词再认评分均有相关性(分别r=0.869、-0.621、-0.759,均P0.01;r=0.446、-0.486、-0.361,均P0.05),胼胝体压部FA值与单词再认评分有相关性(r=-0.343,P0.05);3组胼胝体压部及顶叶MD值与MMSE、单词回忆及单词再认评分均有相关性(分别r=-0.612、0.547、0.586,均P0.01;r=-0.576、0.499、0.519,均P0.01),内囊前肢MD值与MMSE评分相关(r=-0.340,P0.05)。结论 MCI及轻中度AD患者存在脑白质选择性微细结构损害,且该损害出现在与高级皮层功能相关的脑区,而与初级功能相关的区域未见明显受损。     

磁共振弥散张量成像与急性脑梗死患者认知功能的关系

目的 利用磁共振弥散张量成像(DTI)评估急性脑梗死患者的认知功能.方法 分别对30例急性脑梗死患者及30名健康志愿者进行DTI检查,观察兴趣区(ROIs)表观扩散系数(ADC)及部分各向异性(FA)的变化,同时评定患者的认知功能及神经功能缺损评分,分析内在的相关性.结果 脑梗死患者组梗死区FA值、ADC值(×10-3 mm2/s)明显下降,平均FA值、ADC值分别为0.12±0.01、1.08±0.11,其对侧相应部位平均FA值、ADC值为0.35±0.08、3.46±0.26,两者相比差异有统计学意义(P＜0.05);脑梗死患者健侧ADC、FA值与对照组相应部位对比差异无统计学意义.脑梗死同侧内囊后肢、大脑脚、皮质脊髓束与健侧相应部位相比,平均FA值明显下降(P＜0.05).脑梗死患者梗死区FA值、ADC值与认知功能呈正相关,与EDSS评分具有负相关性.结论 DTI与急性脑梗死患者认知功能具有一定的相关性,可为脑梗死患者认知功能障碍的早期诊断及早期治疗提供一些依据.     

轻度认知障碍和阿尔茨海默病患者认知功能和MRI对照研究

目的探讨轻度认知障碍（MCI）和阿尔茨海默病（AD）的认知功能及影像学特点。方法回顾性分析经临床确诊的21例MCI和24例AD患者的临床资料。所有实验对象均用简易智力量表（MMSE）和蒙特利尔认知评估（MoCA）测定。结果MCI与AD的认知功能损害相比较：除了MMSE的记忆力组间无统计学意义（P＝0．28）,其余均有统计学差异（P〈0．05）。MoCA比MMSE具有更好的敏感性。AD的MRI表现：脑萎缩,特别是海马存在不同程度的萎缩;老年性脑改变;MCI的MRI主要表现为脑白质脱髓鞘病变,少数提示轻度脑萎缩或未见明显异常。结论MCI和AD患者早期均表现为记忆力下降,对记忆力减退人群进行MMSE、MoCA量表筛查有助于AD的早期诊断。AD患者到中晚期治疗较困难,因此早期诊断及干预对延缓病程起积极作用。     

轻中度阿尔茨海默病与遗忘型轻度认知功能障碍患者的平衡功能

目的 探讨遗忘型轻度认知功能障碍(amnestic mild cognitive impairment,aMCI)和轻中度阿尔茨海默(Alzheimer's disease,AD)患者的平衡功能变化,以及人体姿势平衡仪在鉴别aMCI、轻中度AD以及健康人群中的应用价值.方法 应用人体姿势平衡仪对20例aMCI和20例轻中度AD患者的平衡功能进行测试,并选取20名年龄性别相匹配的健康体检者作为对照.结果 轻中度AD患者的所有平衡仪检测指标均与健康对照有显著差异,其中AD组支撑面积(15 398±926)mm2,睁眼状态时X轴平均位移(Mean X,10.2±4.1)mm、Y轴平均位移(Mean Y,-29.8±10.2)mm、X轴最大值(Max X,30.5±9.5)mm、Y轴最大值(Max Y,42.7±11.4)mm、姿势图长度(LSKG,528.4±105.4)mm、姿势图面积(SSKG,252.5±89.7)mm2,闭眼状态时Mean X(13.1±4.5)mm、Mean Y(-58.2±16.9)mm、Max X(37.7±10.5)mm、Max Y(78.5±18.7)mm、LSKG(816.6±171.3)mm、SSKG(649.0±129.7)mm2,与健康对照组各指标[支撑面积(31 654±2132)mm2,睁眼状态时分别为(5.8±1.4)mm、(-14.9±4.4)mm、(18.3±4.1)mm、(23.3±6.8)mm、(390.3±68.4)mm、(178.8±40.9)mm2;闭眼状态时(7.9±1.5)mm、(-25.6±5.4)mm、(24.7±7.3)mm、(39.9±9.9)mm、(533.5±97.4)mm、(290.5±73.3)mm2]比较差异均有统计学意义(支撑面积t=8.57,睁眼状态时F值分别为17.41、38.10、60.46、102.10、29.31、27.85,闭眼状态时F值分别为37.20、541.79、34.51、185.56、122.83、384.27,均P＜0.05);支撑面积和Mean Y在aMCI组[(23 921±1637)mm2,(-39.8±8.6)mm]和健康对照组[(31 654±2132)mm2,(-25.6±5.4)mm]之间差异有统计学意义(t=6.50,P=0.038;t=-15.34,P=0.012).结论 轻中度AD及aMCI患者均存在平衡功能障碍,人体姿势平衡仪检测对临床上运动表现和平衡能力均在正常范围的aMCI、轻中度AD以及健康人群具有鉴别意义.

Abstract：

Objective To investigate alterations of balance function in patients with mild-moderate Alzheimer's disease (AD) and with amnestic mild cognitive impairment (aMCI),and the possibility of using posturography to differentiate aMCI,mild-moderate AD and normal subjects. Methods The balance function of 20 patients with mild-moderate AD and 20 patients with aMCI were evaluated by posturography,and 20 healthy subjects of the same age range were recruited as controls.Results All posturography measures were significantly altered in mild-moderate AD patients compared with normal controls,with limits of stability( ( 15 398 ± 926 ) mm2 vs ( 31 654 ± 2132 ) mm2 ),open-eyed Mean X ( ( 10. 2 ± 4. 1 ) mm vs (5.8 ± 1. 4)mm) ,Mean Y(( -29.8 ± 10.2)mm vs ( -14.9 ±4.4) mm),Max X((30.5 ±9.5)mm vs (18.3 ±4. 1)mm ),Max Y((42.7 ± 11.4)mm vs (23.3 ±6.8)mm),LSKG((528.4 ± 105.4)mm vs (390. 3 ± 68.4 ) mm ),SSKG ( ( 252. 5 ± 89. 7 ) mm2 vs ( 178.8 ± 40. 9 ) mm2 ),close-eyed Mean X ((13. 1 ±4. 5) mm vs (7.9 ± 1.5)mm) ,Mean Y (( -58.2 ± 16. 9) mm vs ( -25.6 ±5.4) mm) ,Max X ((37.7±10.5)mm vs (24.7 ±7.3) mm ),Max Y ((78.5±18.7)mm vs (39.9 ±9.9) mm),LSKG ((816.6±171.3) mm vs (533.5 ±97.4) mm),SSKG((649.0 ± 129.7) mm2 vs (290.5 ±73.3) mm2),respectively ( t = 8.57; open-eyed F = 17.41,38. 10,60. 46,102. 10,29. 31,27. 85; close-eyed F = 37.20,541.79,34. 51,185.56,122. 83,384. 27 ;all P ＜0. 05) ;limits of stability ( (23 921 ± 1637 )mm2 vs (31 654 ±2132 ) mm2 ) and mean Y ( Antero-posterior sway,( - 39. 8 ± 8. 6 ) mm vs ( - 25.6±5.4 ) mm) were the only parameters which discriminated between aMCI and normal controls,respectively ( t = 6. 50,P = 0. 038; t =- 15.34,P = 0. 012). Conclusions Impairment in balance is a feature not only of mild-moderate AD,but also of aMCI,and posturography may be used as a possible test in differentiating between normal subjects,patients with aMCI and patients with mild-moderate AD whose motor performance and balance features are otherwise clinically normal,limits of stability and mean Y are the most sensitive parameters.     

癫(癎)患者磁共振弥散张量成像及其与智能损害的关系

目的 采用磁共振弥散张量成像技术研究癫(癎)患者智能损害的相关脑区及病理改变,探讨其可能的发生机制.方法 对44例癫(癎)患者和20名健康人进行韦氏成人量表和磁共振弥散张量成像检查.结果 癫(癎)组患者的全量表智商(FIQ,98.19±17.76)、语言智商(VIQ,100.52±17.63)、操作智商(PIQ,95.10±16.72)均显著低于对照组(VIQ:109.77±13.54、PIQ:108.11±12.17、FIQ:109.81±10.57).癫(癎)智能缺损患者胼胝体膝部平均扩散率(MD值)高于癫(癎)智能正常组,双侧内囊前肢、左侧内囊膝部、左侧外囊、双侧枕叶白质和双侧壳核的各向异性(FA)值低于癫(癎)智能正常组,差异有统计学意义(P＜0.05).相关分析发现,右枕叶FA值与FIQ呈正相关;右侧额叶MD值与VIQ呈负相关;右侧枕叶FA值与VIQ呈正相关;两侧枕叶FA值均与PIQ正相关.结论 本组癫(癎)患者在FIQ、VIQ、PIQ均存在损害.癫(癎)患者伴有智能缺损的胼胝体膝部平均扩散率增加,双侧内囊前肢、左侧内囊膝部、左侧外囊、双侧枕叶白质和双侧壳核各向异性减低;枕叶的各向异性减低与FIQ减低有关,额叶平均扩散率增加与VIQ减低有关,皮质下白质在认知中可能起较重要的作用.     

阿尔茨海默病患者脑白质纤维束改变与执行功能损害的关系

目的 探讨阿尔茨海默病(AD)患者脑白质纤维束改变与执行功能损害的关系。方法 选择2019年12月-2022年1月深圳市罗湖区人民医院收治的118例AD患者作为研究对象,通过Mattis痴呆量表的主动/持续部分(MDRSI/P)评估患者执行功能,根据患者执行功能情况分为执行功能障碍组(n=46)和执行功能正常组(n=72)。对比两组患者各区域脑白质纤维束FA值以及一般资料,采用多因素Logistics回归分析AD患者执行功能障碍的影响因素。采用Pearson分析各区域脑白质纤维束FA值与BADS评分之间的相关性,采用Spearman分析各区域脑白质纤维束FA值与执行功能障碍之间的相关性。构建贝叶斯网络模型,使用Netica软件进行贝叶斯网络推理,并对模型效能进行评价。结果 118例AD患者中,有46例出现执行功能障碍,发病率为38.98%。执行功能障碍组患者各区域的脑白质纤维束FA值均明显低于执行功能正常组,差异具有统计学意义(P<0.05)。执行功能障碍组与正常组患者在病程、痴呆程度、画钟试验得分、BADS评分、MMSE评分、NPI评分、UPDRS评分、ADAS-Cog评分、W...     

阿尔茨海默病患者认知功能损害的调查研究

目的 探讨阿尔茨海默病（AD）患者的认知功能损害特征.方法 采用精神状态简易速查表（MMSE）对32例AD患者及32例正常老年人（对照组）进行了测评,并将测评结果加以比较.结果 AD组患者的MMSE总分及各项分测验（除物体命名外）评分均极明显低于正常对照组（P＜0.01）.轻度痴呆组在时间定向、地点定向、语言即刻记忆、注意和计算、短程记忆、阅读理解、言语表达及图形描述等项评分均极明显高于中度痴呆（P＜0.01）.结论 AD患者普遍存在着认知功能损害,且与痴呆的程度有关.     

阿尔茨海默病额叶白质损害的DTI与临床执行功能的关系

目的 分别应用磁共振扩散张量成像(diffusion tensor imaging,DTI)及额叶功能评定量表(frontal assessment battery,FAB)评价阿尔茨海默病(Alzheimer disease,AD)患者额叶白质损害与执行功能,并对两者的关系进行研究.方法 对15例AD组和15例对照组应用FAB测得评分,并且进行DTI扫描,测量额叶白质的部分各向异性(fractional anisotropy,FA)和半均扩散系数(average diffusion coefficient,ADC)值,对两组额叶白质区域的FA值和ADC值及FAB评分进行比较,并评价额叶白质的FA值和ADC值与临床执行功能评分之间的相关关系.结果 AD患者FAB值及额叶白质FA值均较对照组显著降低,额叶白质FA值与FAB值呈正相关(r=0.678,P=0.003).结论 FAB能够实用且有效的检测AD患者额叶执行功能的改变,FA值可反映AD患者额叶白质受损程度及其与执行功能的关系.     

轻度阿尔茨海默病及轻度认知障碍患者汉语双字词判断反应时研究

目的探索轻度阿尔茨海默病(AD)和轻度认知障碍(MCI)患者在汉语词汇认知加工过程中语义和语音时间进程及模式的改变特点。方法对32例轻度AD(AD组)和39例MCI患者(MCI组)以及40名健康对照(NC组)进行汉语双字词判断任务,采用语义、同音、变调和无关对照四种启动类型,设立长短两种刺激呈现间隔(SOA),被试对目标词进行真假词判断,分别记录被试的反应时和错误率,判断是否出现语义或语音启动效应,通过方差分析和t检验方法对实验数据进行统计分析。结果轻度AD和MCI患者各启动类型的平均反应时较NC分别延长411ms和234ms(P<0.01),NC组在长SOA时的反应时较短SOA时快53ms(P=0.002),而轻度AD组和MCI组长SOA时的反应时分别较短SOA时延长95ms和74ms(分别为P=0.005,P=0.011);各组均出现了语义和语音启动效应,轻度AD和MCI组假词判断的错误率(20.0%和14.4%)明显高于NC组(9.0%,P<0.01)。结论轻度AD及MCI患者汉语词汇加工速度减慢;轻度AD患者的语音提取过程受损,轻度AD及MCI患者语义编码过程可能受损。MCI患者语音加工过程可能正常。     

基于复杂度分析阿尔茨海默病、轻度认知功能障碍患者的脑电特点

目的 探讨阿尔茨海默病(Alzheimer's disease,AD)、轻度认知功能障碍(mildcognitive impairment,MCI)和健康老年人的脑电复杂度(Lemple-Zie complexity,LZC)特点,以及LZC值在鉴别AD、MCI以及健康老年人中的应用价值.方法 对30例AD患者、30例MCI患者及20名健康老年对照者进行安静闭目状态下的脑电监测,用Matlab自编软件计算各组不同导联及脑区的LZC值.结果 (1) AD组、MCI组、对照组全部导联平均值依次是0.396±0.036、0.470±0.051、0.523±0.055,AD组和MCI组与对照组相比均有所降低,差别有统计学意义(F=43.092,P=0.000).(2)AD组的LZC值在各导联处[(0.373±0.042) ～(0.430±0.083)]、全部导联均值、左右半球、双侧额颞区的均明显低于对照组[(0.498±0.067) ～(0.566±0.059)],差异有统计学意义(=3.602 ～ 8.747,P=0.000 ～0.010);且在双侧前中颞、双侧额区、左顶区具有较大降幅,均大于23％.(3)除导联T6外,AD组的LZC值在各导联处[(0.373±0.042) ～ (0.418±0.063)]、全部导联均值、左右半球及双侧额颞区均低于MCI组[(0.455±0.072) ～ (0.489±0.063)],差异有统计学意义(在T5导联处,t =2.038、P=0.041,其余t=4.178 ～7.424,均P=0.000).(4) MCI组的LZC值在全部导联均值、左右半球、双侧颞区、左额、双侧顶区较对照组降低,差异有统计学意义.结论 随着认知功能的降低,脑电信号复杂度值可出现同向改变,说明LZC值可在一定程度上反映大脑认知功能的变化;出现额、颞区复杂度异常的MCI患者与AD的发生存在一定程度的联系.     

Ischemic white matter damage and cognitive impairment

White matter damage may play an important role in the pathogenesis of vascular dementia. White matter abnormalities are easily visualized as white matter high‐intensity lesions (WML) on T2‐weighted magnetic resonance images. The extent of WML may be an indicator of cognitive impairment, in particular, impairment related to frontal lobe dysfunction. However, it is unclear whether the extent of WML is an independent predictor of cognitive impairment. In patients with extensive WML, atrophy of the corpus callosum may be an important predictor of global cognitive impairment. We investigated the relationship between the extent of WML and callosal size with cognitive function in patients who had been diagnosed with lacunar stroke or no specific neurological disease. Multivariate analysis showed that only callosal size and age were significant independent predictors of mini‐mental state examination scores (a measure of global cognitive function), whereas only the extent of WML was an independent predictor of the score on the verbal fluency task (a measure of frontal lobe function). Callosal atrophy may be an important predictor of global cognitive impairment in patients with WML, whereas the extent of WML per se may be related to impairment of frontal lobe function independent of callosal atrophy. White matter high‐intensity lesions with callosal atrophy may indicate a severe form of white matter damage with axonal loss, the degree of which may determine the severity of global cognitive impairment. Our longitudinal study revealed an association between progression of WML and vascular risk factor status during follow up in patients with initially mild WML. Early detection of WML without callosal atrophy at a stage of subtle cognitive impairment and slowing the progression of WML to a severe form with callosal atrophy might prevent the development of dementia.     

Diffusion tensor imaging based white matter changes and antioxidant enzymes status for early identification of mild cognitive impairment

Mild cognitive impairment (MCI) is an early stage of dementia. The changes in white matter integrity and antioxidant enzymes levels are crucial in onset and progression to Alzheimer’s disease (AD). To elucidate the changes in cognitive performance, white matter integrity, oxidative stress marker, for early detection of prodromal state of AD. Fifty cases of MCI and controls (55-75 years) were subjected to Mini Mental State Examination (MMSE), diffusion tensor imaging (DTI) followed by estimation of superoxide dismutase, glutathione peroxidase and lipid peroxidation in serum of MCI and control population. The MMSE scores of MCI subjects were (28±2 - 22.6±1) as compared with controls (28±1- 29±1). DTI metrics fractional anisotropy (FA) values in right and left frontal lobe, fornix, corpus callosum, while apparent diffusion coefficient (ADC) values in right temporal lobe, hippocampus head, corpus callosum right, and forcep major were significantly altered in MCI as compared with controls. Superoxide dismutase, glutathione peroxidase level were lower while lipid peroxidation marker malondialdehyde (MDA) was increased in patients with MCI as compared with controls. The study emphasized that changes in neuro-psychological performance, white matter integrity and antioxidant enzymes level provide early signature for diagnosis of MCI.     

阿尔茨海默病患者的执行功能障碍

目的了解阿尔茨海默病(A lzhe im er d isease,AD)患者执行功能损害状况及对于生活能力的影响,探讨执行功能障碍与记忆等AD常见认知功能损害的相关性。方法运用神经心理学测验的方法对40例AD患者及30例轻度认知功能损害(m ild cogn itive impairm ent,MC I)患者进行执行功能、记忆及其他认知功能检查,同时进行生活能力评定。另外选择40名健康老人作对照。结果AD组的执行功能测验成绩均显著低于健康对照组(P<0.01),其中额叶功能评定量表(FAB)(5.29±2.47)分,执行性画钟作业(CLOX1)(4.63±3.56)分,Stroop测验错误次数(Stroop1)(14.17±8.99)分,词语流畅性测验(RVR)(17.56±10.51)分。除Stroop测验反应时间(Stroop2)外,MC I组的其他执行功能测验成绩显著低于健康对照组(P<0.05),其中FAB为(7.67±2.44)分,CLOX1为(7.86±3.78)分,Stroop1为(7.21±8.07)分,RVR为(30.86±8.38)分。用多元逐步回归方法分析不同认知功能对生活能力的影响,结果为反映执行功能的FAB测验成绩处于第一位,独立与操作性日常生活能力(IADL)相关(β=-0.778,t=-7.079,P<0.01)。各项执行功能测验与年龄相关性不明显(r=0.026~0.250,P>0.05),与简易精神状态量表(MMSE)、记忆测验成绩相关性好(r=0.438~0.786,P<0.01)。结论AD患者具有明显的执行功能障碍;在尚未到达痴呆水平的MC I阶段也可发现执行功能损害。执行功能和整体认知功能及记忆等认知域功能具有良好的相关性。AD患者的执行功能障碍是导致生活能力下降的重要因素。     

Cognitive dysfunctions and white matter lesions in patients with bipolar disorder in remission

OBJECTIVE: To compare cognitive functioning in relation to white matter lesions in bipolar disorder in remission and schizophrenia. METHOD: Cognitive performance and the occurrence of white matter lesions on MRI images of the brain were assessed in 22 patients with bipolar disorder in remission, 22 patients with schizophrenia and 22 healthy volunteers. RESULTS: Performance of tests of memory, speed and cognitive flexibility was significantly impaired in both patient groups. The frequency of white matter lesions did not differ significantly between the three groups. No differences in cognitive performance were found between patients with white matter lesions and patients without such lesions. CONCLUSION: White matter lesions apparently do not underlie cognitive deficits that are found in patients with bipolar disorder in remission and in patients with schizophrenia.     

社区阿尔茨海默病早期征象的研究

目的　了解阿尔茨海默病 (AD)患者的早期征象。方法　在 1997年 6月至 1998年 4月对成都市 5 35 3名年龄≥ 5 5周岁的社区人群进行痴呆患病率调查的基础上 ,于 2 0 0 0年 11月 12日至2 0 0 1年 3月 2 1日仍用两阶段法随访其中的 36 87名正常人群。实际随访 2 86 9名 (77 81% ) ,失访 818名 (2 2 19% )。用美国精神障碍诊断与统计手册第 3版修订本的标准诊断痴呆 ,用美国神经病语言障碍和卒中研究所及阿尔茨海默病与相关障碍协会的AD标准做出可能AD和很可能AD诊断 ,用临床痴呆程度评定量表评定痴呆严重程度。结果　 (1)查出可疑痴呆 5 8例 (2 0 4 % ) ,AD2 5例 (0 88% )。(2 )AD患者年龄 [(79± 6 )岁 ]高于可疑痴呆者 [(76± 8)岁 ]和正常人 [(6 6± 7)岁 ;P <0 0 0 1]。(3)AD患者基线简易精神状态检查 (MMSE)总分及各分项评分均低于可疑痴呆者和正常人 ,均P <0 0 0 1。AD患者随访时的MMSE总分和积木测验评分下降了 [(6 86± 5 77)分和 (4 11± 6 4 1)分 ],下降程度快于可疑痴呆者 [(3 5 5± 4 5 0 )分和 (4 89± 6 89)分 ]和正常人 [(0 5 6± 3 76 )分和 (1 11± 6 86 )分 ;P <0 0 5 ]。有记忆力减退病史者 (2 83例 )中 ,AD患者的比例 (44 0 % )显著高于可疑痴呆者 (32 8% )和正常人 (9     

Assessment of white matter tract damage in mild cognitive impairment and Alzheimer's disease

Diffusion tensor MRI‐based tractography was used to investigate white matter (WM) changes in the major limbic (i.e., fornix and cingulum) and cortico‐cortical association pathways [i.e., the uncinate fasciculus, the inferior fronto‐occipital fasciculus, the inferior longitudinal fasciculus (ILF), the superior longitudinal fasciculus, and the corpus callosum] in 25 Alzheimer's disease (AD) patients, 19 amnestic mild cognitive impairment (aMCI) patients, and 15 healthy controls (HC). Mean diffusivity (MD), fractional anisotropy (FA), as well as axial (DA) and radial (DR) diffusivities were measured for each tract, using an atlas‐based tractography approach. The association of WM tract integrity with hippocampal volume was also assessed. MD values were significantly different among groups in all WM tracts (P values ranging from 0.002 to 0.03), except in the fornix (P = 0.06) and the inferior fronto‐occipital fasciculus (P = 0.09). Conversely, FA was significantly different among groups in the fornix only (P = 0.02). DA values were significantly different among groups in all WM tracts (P values ranging from 0.001 to 0.01), except in the fornix (P = 0.13) and the cingulum (P = 0.29). Significantly different DR values among groups were found in the fornix (P = 0.02) and the ILF (P = 0.01). In the fornix and cingulum, DR was significantly more increased than DA in both patient groups compared to HC. No difference in DA versus DR was found in cortico‐cortical WM tracts. DA values in the fornix were significantly correlated with the hippocampal volume. This study demonstrates a different pattern of WM involvement in the limbic and cortico‐cortical association pathways in aMCI and AD patients. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.