轻度认知障碍老年患者功能磁共振成像特点

目的研究轻度认知障碍老年患者的功能磁共振成像特点。方法选取该院及首都医科大学宣武医院2011年2月至2013年11月收治的轻度认知障碍老年患者40例作为试验组,40例健康老龄为对照组。对两组进行词汇流畅作业的功能磁共振成像检查,比较两组的词汇流畅性以及脑激活强度。结果试验组患者的词汇流畅性低于对照组,平均脑激活强度小于对照组,患者右侧额叶激活体积大于对照组,但其余脑区均小于对照组(P0.05)。结论健康老年人的脑功能明显优于轻度认知障碍患者的脑功能,左前额叶与两组脑功能的差异有密切的关系。     

多系统萎缩和帕金森病患者的磁共振影像学分析

目的 探讨多系统萎缩(multiple system atrophy,MSA)和帕金森病(Parkinson disease,PD)的磁共振成像(MRI)影像学特点,为早期诊断和鉴别诊断提供依据.方法 回顾性分析经临床确诊的24例MSA、30例PD和30例健康人的MRI资料,观察指标包括:(1)T2WI信号改变:十字征(即脑桥基底部十字样高信号)、裂隙征(即壳核外侧缘裂隙样高信号);(2)脑室、脑池扩大:四脑室、桥池、延池;(3)脑实质萎缩:延髓、脑桥、小脑中脚、壳核萎缩.并测量中脑面积、脑桥面积和小脑中脚宽度.结果 MSA患者中均出现至少1项MRI异常指标,并表现一定的分型差异.敏感性较高的指标是:小脑中脚萎缩(79.2%)、脑桥萎缩(79.2%)和十字征(75.0%);特异性和阳性预测值高的指标是:十字征(均为100%)、裂隙征(均为100%)、小脑中脚萎缩(93.3%和90.1%)、脑桥萎缩(96.7%和95.0%).MSA组脑桥面积、中脑面积及小脑中脚宽度分别为(288.7±75.4)mm2、(127.8±25.8)mm2及(10.7±2.8)mm,与PD组[分别为(477.5±54.3)mm2、(145.9±21.6)mm2及(16.2±1.3)mm]、对照组[分别为(454.5±36.8)mm2、(146.4±17.4)mm2及(16.7±1.2)mm]比较,差异有统计学意义(P＜0.05).结论 MRI有助于MSA的诊断及其与PD的鉴别诊断,对MSA的分型具有一定的价值.

Abstract：

Objective To explore the MRI features of patients with multiple system atrophy (MSA) and Parkinson's disease (PD) for providing early evidence in differential diagnosis. Methods The MRI features of 24 patients with MSA, 30 patients with PD and 30 healthy people as controls were retrospectively analyzed. Abnormal intensity in MRI included the hot-cross bun sign and the slitlike changes. The atrophies of brain included cerebellar, middle cerebellar peduncles, medulla oblongata and pon. Cerebral ventricle dilatation included fourth ventricle and cisterna pontis. The midbrain area, pons area and middle cerebellar peduncles width were measured. Results All patients with MSA had at least one of the features observed on MR images, and there were some differences in the subtypes of MSA. The high sensitive features were the atrophies of middle cerebellar peduncles (79.2%), the atrophies of pons (79.2%) and the hot-cross bun sign (75.0%). The parameters with high specificity and high positive predictive value were hot-cross bun sign (both 100%), the slit-like sign (both 100%), the atrophies of middle cerebellar peduncles (93.3% and 90.1%), and the atrophies of pons (96.7% and 95.0%). MSA group had the statistically significantly decreased values of pons area, midbrain area and middle cerebellar peduncles width [(288. 7±75. 4) mm2, (127.8±25.8) mm2 and (10. 7±2.8) mm, respectively], as compared with PD group [(477. 5 ± 54. 3) mm2, (145.9±21.6) mm2 and (16.2±1.3) mm, respectively] and healthy group [(454. 5±36. 8) mm2 , (146.4±17.4) mm2 and (16.7±1.2) mm, respectively] (all P ＜0. 05). Conclusions The routine MRI is helpful in differential diagnosis between MSA and PD and has some values in diagnosing the subtypes of MSA.     

磁共振标准化测量在老年性认知障碍影像解剖学研究中的价值

目的观察并比较老年性认知障碍中的阿尔茨海默病(AD)、轻度认知障碍(MCI)患者与作为对照健康老年人(NC)的颅脑磁共振成像(MRI)影像测量数据的差异性,优化老年性认知障碍的影像诊断方法。方法选取50例受试者的MRI(1 mm薄层冠状位序列)扫描图像,其中12例AD患者、18例MCI患者及20例对照的健康者,然后分别对三组受试者进行MRI扫描,对获得的图像进行数据的分析采集,进一步统计学分析,数据包括哈氏值(HI)、脑室指数(VI)、前角指数(FHI)、三脑室宽(TVW)、皮层脑沟宽度(CSW)、外侧裂宽度(LFW)及海马体积的计算等线性指标,得出最后的分析结果。结果各类线性测量指标HI、FHI、TVW、LFW均具有显著的统计学意义(P0.05),而海马标准化体积存在组间差异(P0.05),MCI组和AD组的海马体积存在显著侧别差异(P0.05)。结论老年性认知障碍中无论是对AD还是MCI,简便、易行的标准化线性测量及标准化海马体积的测量能很好地诠释其颅脑影像特异性的改变,提高诊断的精准性。     

不同亚型多系统萎缩患者磁共振成像特征分析

目的分析多系统萎缩(MSA)不同亚型的磁共振成像(MRI)特征,并探讨其意义。方法选择MSA患者32例,其中15例行MRI,并用日常生活活动能力(ADL)的3个重要事件对疾病进展进行评估。结果 13例小脑萎缩型(MSA-C)患者中,MRI检查脑桥十字征0期2例、Ⅰ期1例、Ⅱ期2例、Ⅲ期4例、Ⅳ期3例、Ⅴ期1例,壳核裂隙征分期均为0期;2例帕金森型(MSA-P)患者脑桥十字征和壳核裂隙征分期均为0期。13例MSA-C患者中,5例脑桥十字征未达Ⅲ期者,行走不稳3例,其中1例为辅助行走状态;4例Ⅲ期者均行走不稳,其中2例需辅助行走;3例Ⅳ期者中,辅助行走1例,依靠轮椅2例;1例V期者依靠轮椅。2例MSA-P患者中,可独立行走1例,辅助行走1例。结论头部MRI脑桥十字征、壳核裂隙征有助于MSA亚型的鉴别,且影像学特征分期与病情进展程度有一定关系。     

代谢综合征对皮质下缺血性脑血管病影像学损害的影响

目的 探讨代谢综合征及其各因子对皮质下缺血性脑血管病(SIVD)影像学损害的影响. 方法 选取120例SIVD患者(SIVD组),年龄其中包括非代谢综合征患者25例,代谢综合征倾向患者25例,代谢综合征患者70例.代谢综合征的诊断标准采用美国国家胆固醇教育计划成人治疗专家组Ⅲ(NCEP-ATPⅢ)标准.SIVD影像学损害采用改良Scheltens量表对头颅MRI进行评价,分为脑室旁、脑白质、基底节三个脑区评定并计算总分. 结果 代谢综合征倾向组脑室旁、脑白质、基底节评分、Scheltens总分[(3.75±1.60)分、(10.67±5.26)分、(3.21±2.62)分、(17.62±8.32)分]和代谢综合征组[(4.21±1.09)分、(13.79±5.25)分、(6.90±4.25)分、(24.90±9.25)分]均显著高于非代谢综合征组[(2.76±1.62)分、(6.36±3.93)分、(1.52±1.50)分、(10.58±5.89)分,均P＜0.05].腰围与脑白质得分及Scheltens总分呈显著正相关(r=0.185,P=0.046; r=0.488,P＜0.001);三酰甘油(TG)与脑白质、基底节得分有显著正相关(r=0.188,P=0.042; r=0.311,P=0.001);空腹血糖与脑白质、基底节得分以及Scheltens总分呈显著正相关(r=0.235,P=0.011; r=0.229,P=0.013; r=0.206,P=0.027);高密度脂蛋白胆同醇(HDL C)与脑白质、基底节以及Schehens总分呈显著负相关(r=-0.238,P=0.010; r=-0.189,P=0.042;r=-0.335,P＜0.001).进一步多元线性逐步回归分析结果发现空腹血糖、HDL C与脑白质评分显著相关(P均＜0.05);TG与基底节评分显著相关(P＜0.05);腰围、空腹血糖、HDL-C与Scheltens总分显著相关(P均＜0.05). 结论 代谢综合征及其各因子与SIVD影像学损害相关,其中腹型肥胖、TG、空腹血糖、HDL-C是SIVD的重要危险因素.     

皮质下缺血性血管性认知功能障碍的静息态功能磁共振研究

目的探讨静息态功能磁共振低频振幅(ALFF)的分析方法在皮质下缺血性血管性认知功能障碍中的价值。方法选择49例缺血性脑小血管病患者经临床痴呆量表评分后,分为血管性痴呆(VaD)组10例,非痴呆型血管性认知功能障碍(VCIND)组20例,认知功能正常为对照组19例。分别采集高分辨率结构像和静息态功能磁共振数据,通过ALFF分析方法计算并对比3组患者脑功能活动的改变。观察VaD组ALFF统计脑图与认知量表评分的相关性。结果与对照组比较,VaD组内侧前额叶、后扣带回及双侧颞叶脑区ALFF明显降低,额中回、额上回、顶下小叶脑区ALFF明显升高,VCIND组内侧前额叶ALFF明显降低,左侧顶叶及颞中回ALFF明显升高(P<0.05);与VCIND组比较,VaD组后扣带回/楔前叶、左侧小脑区ALFF明显降低,双侧额叶、颞叶及前扣带回明显升高(P<0.05);回归灰质体积后,VaD组ALFF统计脑图与多个临床量表评分存在相关性(P<0.05)。结论血管性认知功能障碍患者存在以执行功能障碍为主的多个领域的认知功能障碍,其认知功能障碍可能与额叶-皮质下环路受损有关,ALFF在血管性认知功能障碍及其早期诊断中有重要价值。     

皮质下脑梗死的磁共振成像研究进展

<正>皮质下脑梗死(subcortical infarction)具有起病隐匿、症状多样,如不及时治疗致残率高等特点,是危害人类生命健康的常见病。由于皮质下脑梗死起病症状多样,许多患者以眩晕、轻度和(或)渐进性肢体无力、面瘫、认知障碍等症状起病。因此,仅根据临床症状很难进行准确的早期诊断,从而     

MRI测量的海马、内嗅皮质体积与轻度认知障碍相关性的临床研究

目的 研究轻度认知障碍(mild cognitive impairment,MCI)与海马和内嗅皮质体积变化的相关性以及影响因素,探讨MRI测量海马和内嗅皮质体积鉴别MCI与认知功能正常(normal cognitive,NC)的价值.方法 从体检者中入选MCI组21例,NC组18名,进行一般情况评定、实验室检查和神经心理量表评测.应用MRI测量海马和内嗅皮质体积,并分析其与记忆功能的相关性;非条件logistic回归分析海马和内嗅皮质体积诊断MCI的特异性和敏感性;多重线性回归分析海马和内嗅皮质体积的影响因素.结果 MCI患者海马和内嗅皮质体积分别为(6.19±0.74)和(2.66±0.17)cm~3;显著小于NC组的(6.80±0.79)和(3.03±0.12)cm~3(P<0.05).海马体积与内嗅皮质体积显著相关(r=0.566,P<0.001);海马体积与临床记忆量表总分显著相关(r=0.430,P=0.04),内嗅皮质体积与临床记忆量表总分显著相关(r=0.722,P<0.001).应用海马体积区分MCI和NC的特异性为66.7%,敏感性为76.2%;应用内嗅皮质体积区分MCI和NC的特异性为88.9%,敏感性为90.5%.另外,海马体积与餐后2 h血糖(P<0.05)、收缩压(P<0.05)、舒张压(P<0.05)和血浆总胆固醇水平(P<0.01)呈负相关,而内嗅皮质体积则与之无关.结论 内嗅皮质和海马体积萎缩与记忆障碍密切相关,MRI测量的内嗅皮质和海马体积对MCI与NC的鉴别具有一定价值,而且内嗅皮质体积的特异性和敏感性优于海马体积.血压、血糖和血脂水平增高可能通过影响海马体积.     

皮层下缺血患者认知功能评估及功能磁共振研究

目的 利用磁共振弥散张量成像(DTI)和磁共振质子波谱分析(MRS)技术探讨皮层下缺血(SIVD)导致认知功能障碍患者的影像学特征.方法 52例皮层下缺血性脑血管病患者经认知量表评分后32例有认知障碍归入血管性认知功能障碍(VCI)组,20例无认知障碍作为对照组,完成DTI和MRS检查.计算双侧额叶、颞叶、顶叶、枕叶和半卵圆区的表观弥散系数(ADC)和各向异性(FA)平均值.测定右侧额叶和左侧颞叶N-乙酰基天门冬氨酸(NAA)、肌酸复合物、含胆碱化合物(Cho)、肌醇的峰值.结果 VCI组与对照组相比,在额叶、颞叶、顶叶和半卵圆区FA值降低,ADC值升高(P＜0.05).FA值的降低以额叶、半卵圆区最明显.ADC值升高以颢叶最明显.波谱分析结果,在额叶VCI组与对照组相比NAA/肌酸复合物比值明显降低(1.43±0.08比1.53±0.92),在颢叶VCI组肌醇/肌酸复合物比值升高(0.51±0.06比0.46±0.07),P＜0.05.结论 VCI患者在额叶、半卵圆区FA值明显降低,额叶白质区NAA值明显降低,DTI和MRS可为早期诊断与评估VCI提供有用的指标.

Abstract：

Objective To evaluate the imaging features of patients with vascular cognitive impairment (VCI) induced by Subcortical Ischemic Vascular Disease (SIVD), through magnetic resonance diffusion tensor imaging ( DTI ) and proton spectroscopy ( MRS ) technology. Methods A total of 52 patients with SIVD were enrolled. After analysis of scale score, 32 patients with cognitive impairment were assigned to VCI group and 20 patients with no cognitive impairment were assigned to control group. Both group received DTI and MRS examination. The mean values of apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of the bilateral temporal, frontal, parietal and occipital white matter regions as well as in the bilateral centrum semiovale were calculated. The peak value of MRS of N-acetyl aspartate (NAA) , choline ( Cho), creatine (Cr) and phaseomannite ( mI ) were calculated. Results Compared with control group, FA decreased in the region of temporal, frontal, parietal as well as in the centrum semiovale , and ADC increased in VC[group ( P ＜ 0.05 ) . In the frontal regions and centrum semiovale,the VCI patients had a significant FA decrease. The ADC value increased obviously in the temperal lobe.Spectrum analysis results showed, NAA/Cr was lower than control group in VCI group in the frontal lobe (1.43 ±0.08 vs 1.53 ± 0. 92), while mI/Cr was higher than control group in the temporal lobe(0. 51 ±0. 06 vs 0. 46 ± 0. 07 ) ( P ＜ 0. 05 ). Conclusion FA in the temporal and centrum semiovale regions of VCI group and NAA in the temporal white matter regions decreased obviously. DTI and MRS could provide a reference value for early diagnosis and assessment of VCI.     

脑小血管病引起的认知障碍磁共振波谱和弥散张量成像

脑小血管病(cerebral small vessel disease,SVD)的临床症状主要表现为认知障碍,病理学改变则表现为白质疏松和(或)腔隙性梗死.然而,目前尚不清楚SVD引起的认知障碍是否与白质损害程度相关.磁共振波谱分析能无创件榆测活体脑组织的代谢产物浓度,直接反映脑代谢;弥散张量成像是特异性观察脑白质的无创性新技术,通过平均弥散、各向异性等不同参数来定量评价脑白质的细微结构异常.磁共振波谱分析与弥散张量成像联合应用能更敏感地显示白质损害程度,为SVD引起的认知障碍提供研究工具.     

轻度认知功能障碍的磁共振弥散张量成像研究

目的 应用磁共振弥散张量成像技术以及自动化影像分析工具研究遗忘型轻度认知功能障碍(aMCI)大脑白质结构的变化.方法 对受试者进行临床和神经心理评估,31例受试者(aMCI组15例,对照组16例)接受磁共振弥散张量成像技术扫描.所有影像资料经与标准模板配准后,采用基于像素的图像分析法确定两组各向异性分数有差异的脑区.结果 aMCI组简易智力状态检查量表(MMSE)(26.93±1.49)分,蒙特利尔认知评估量表(MoCA)(22.73±1.91)分,对照组MMSE(29.44±0.81)分,MoCA(26.50±1.17)分,差异有统计学意义(P<0.05).在aMCI组双侧额叶部分白质区域异性分数值低于对照组(P<0.1301).结论 额叶白质损伤可能参与了aMCI的病理生理过程的变化.     

缺血性脑血管病患者认知功能障碍的血管因素分析

目的探讨缺血性脑血管病患者血管因素与认知功能障碍关系。方法将60例缺血性脑血管病患者分为轻危组、中危组和高危组;应用经颅多普勒超声(TCD)检测脑血管血流动力学,蒙特利尔量表进行认知功能评定。结果高危组与低危组在视空间和执行功能、注意力、计算力、抽象概括能力、命名、记忆、时间定向方面有显著差异(P<0.05);中危组与低危组比较在视空间和执行功能、注意力、计算力、抽象概括能力、记忆方面有显著差异(P<0.05);视空间、命名、计算、语言、时间定向各方面中危组较高危组有显著差异(P<0.05)。高危组TCD异常比例明显高于轻危组(P<0.05),主要表现在大脑中动脉、椎动脉、基底动脉流速增快,频谱异常。中危组TCD结果异常比例明显高于轻危组,主要表现在各动脉流速增快;高危组较中危组在流速增快与频谱异常比例显著增高(P<0.05)。结论缺血性脑血管病患者随着危险因素增多,其认知功能障碍越显著,TCD各指标异常率也随之升高。     

轻度认知障碍患者多模态磁共振特征

目的 探讨轻度认知损害者(MCI)和阿尔茨海默病(AD)患者多模态磁共振成像特征与认知功能的关系.方法 共纳入9例遗忘型MCI,15例轻度AD及11例正常对照,以简明精神状况检查(MMSE)和认知功能筛查测验(CASI)评估总体认知功能,对高分辨率结构像进行基于体素形态学分析(VBM),测量扩散张量成像(DTI)图像、各脑区白质各向异性比值(FA)和平均表观弥散系数(ADC),分析脑结构萎缩及白质DTI指标与认知评分的相关性.结果 MMSE和CASI评分与颞、额、顶、扣带回、海马旁回等结构灰质体积改变呈正相关(P<0.001),MMSE和CASI总分与颞、顶叶以及海马旁回的FA值呈正相关,与ADC值呈负相关(P<0.05).结论 MCI和AD患者认知功能与颞、顶、海马旁回等脑区萎缩及白质微观结构损伤密切相关,多模态影像技术可作为认知损害脑机制研究的重要技术手段.     

皮质下缺血性脑血管病执行功能损害与脑白质结构的相关性研究

目的 探讨皮质下缺血性脑血管病(SIVD)执行功能损害、MRI脑白质病变和DTI脑白质的微结构变化及其临床相关因素.方法 应用Stroop色词测验(CWT)、连线测验(TMT) 和积木测试(BDT)评价24例SIVD患者和14例认知正常老年人的执行功能,其中SIVD患者分为痴呆(VD)组12例,认知障碍无痴呆(VCIND)组12例;依据年龄相关白质改变的评分方法(ARWMCrs) 测量常规MRI上白质病变程度,同时应用DTI分别测定额、颞、顶、枕叶及胼胝体压部白质正常区的各向异性分数(FA)和平均扩散率(MD)值,分析各影像学测量指标与执行功能的相关性.结果 (1)与健康对照组比较,VD组执行功能三项测验均显著减退,VCIND组BDJ评分降低,TMT时间延长,差异有统计学意义(P<0.05);(2)与对照组相比较,VD、VCIND组白质病变评分增高,分别为12.820±3.573、10.500±2.953(P＜0.05);胼胝体压部MD值均升高,具有统计学差异(P＜0.05);VD患者双额叶、右颞叶、右枕叶、双顶叶及胼胝体压部FA值下降(P＜0.05);VCIND组左额叶、双顶叶白质FA值下降(P＜0.05);(3)与SIVD患者执行功能相关的影像学指标有:左额叶、双颞叶、右顶叶白质正常区FA值、胼胝体压部MD值(P＜0.05).结论 (1)SIVD患者存在执行功能障碍,与其脑白质病变程度可能有关;(2)DTI可以显示SIVD患者常规MRI无法显示的脑白质选择性微结构损害;(3)SIVD患者的多个脑白质区FA及MD与CWT、TMT和BDT存在相关性,提示白质微结构的损害可能反映执行功能的下降.     

Brain magnetic resonance imaging abnormalities in patients with heart failure

BACKGROUND: Although heart failure (HF) is a common cardiovascular disorder, to date little research has been conducted into possible associations between HF and structural abnormalities of the brain. AIMS: To determine the frequency and pattern of magnetic resonance imaging (MRI) abnormalities in outpatients with chronic HF, and to identify any demographic and clinical correlates. METHODS: Brain MRI scans were compared between a sample of 58 HF patients, 48 controls diagnosed with cardiovascular disease uncomplicated by HF (cardiac controls) and 42 healthy controls. Deep, periventricular and total white matter hyperintensities (WMH), lacunar and cortical infarcts, global and medial temporal lobe atrophy (MTA) were investigated. RESULTS: Compared to cardiac and healthy controls, HF patients had significantly more WMH, lacunar infarcts and MTA, whereas cardiac controls only had more MTA, compared to healthy controls. Age and left ventricular ejection fraction (LVEF) were independently associated with total WMH. Age and systolic hypotension were associated with MTA in HF patients and cardiac controls. CONCLUSION: Our results suggest that cardiac dysfunction contributes independently to the development of cerebral MRI abnormalities in patients with HF. Age and low LVEF are the principal predictors of cerebral WMH in patients with HF and in cardiac controls.     

White matter lesions on brain magnetic resonance imaging scan and 5-year cognitive decline: the Honolulu-Asia aging study

OBJECTIVES: To study white matter lesions (WMLs) and 5‐year cognitive decline in elderly Japanese‐American men. DESIGN: Longitudinal cohort study. SETTING: Population‐based study in Honolulu, Hawaii. PARTICIPANTS: Japanese‐American men aged 74 to 95 from the Honolulu‐Asia Aging Study (HAAS) who were free of prevalent dementia, underwent a protocol brain MRI scan at the fifth HAAS examination (1994–1996), and returned for cognitive testing 5 years later (N=267). MEASUREMENTS: WMLs were dichotomized as present (grade 3–9, 38.2%) or absent (grade 1–2, 61.8%). Cognitive function was measured using the Cognitive Abilities Screening Instrument (CASI), and 5‐year cognitive decline was defined as a drop in CASI score of 12 points or more (1 standard deviation). RESULTS: Men with WMLs on MRI at baseline were significantly more likely to experience cognitive decline at 5 years than those without (22.4% vs 34.4%, P=.03). Using multiple logistic regression, adjusting for age, education, apolipoprotein (Apo)E4 allele, large or small infarcts on MRI, baseline CASI score, and hypertension, those with WMLs were significantly more likely to develop 5‐year cognitive decline (odds ratio=2.00, 95% confidence interval=1.10–3.65, P=.02). This association was stronger in men who were cognitively intact and free of the ApoE4 genotype and clinical stroke at baseline. CONCLUSION: Presence of WMLs on MRI was significantly associated with higher odds of 5‐year cognitive decline in older Japanese‐American men. Presence of WMLs may help identify people at risk for developing dementia, who may benefit from early intervention.     

静息态功能磁共振在皮质下缺血性血管性认知损害中的应用

皮质下缺血性血管病(subcortical ischemic vascular disease, SIVD)被认为是引起血管性认知损害(vascular cognitive impairment, VCI)的最重要和常见的原因。若能早期发现皮质下缺血性血管性认知损害(subcortical ischemic vascular cognitive impairment, SIVCI)或皮质下血管性认知损害(subcortical vascular cognitive impairment, sVCI)患者,会使血管性痴呆(vascular dementia, VaD)在发生之前得到识别甚至逆转其进程成为可能。最近的研究显示,静息态功能磁共振(resting-state fMRI, rsfMRI)有可能为 SIVCI 的诊断提供客观依据。文章对 rsfMRI 在 SIVCI 诊断中的应用进行了综述。     

皮质下血管性认知功能障碍患者血清sCD40L水平的变化

目的 探讨皮质下缺血性脑血管病(SIVD)认知障碍患者血清中可溶性CD40配体(sCD40L)的水平及其与认知障碍、白质病变(WML)的相关性.方法 对SIVD中19例血管性痴呆(VD)患者、20例血管性无痴呆型认知损害(VCIND)患者及15例年龄及性别相当的健康老年人行认知功能测试,采用酶联免疫吸附法( ELISA)检测受试者血清sCD40L水平;同时行头颅MRI扫描,应用年龄相关白质改变分级方法,对WML评分,进一步分析sCD40L与认知功能、WML的关系.结果 ①SIVD两组与正常对照组相比,血清sCD40L浓度增高(P＜0.05),两组之间差异不显著(P＞0.05).②SIVD患者sCD40L水平与MMSE、MoCA、WML评分均无明显相关性(P＞0.05).结论 ①皮质下血管性认知障碍患者血清sCD40L水平较正常老年人均明显升高,sCD40L可能参与SIVD发生、发展;②血清sCD40L水平与认知功能损害、白质病变程度无明显相关.     

轻度认知功能损害患者静息状态脑默认活动网络的功能磁共振研究

目的 采用静息状态功能磁共振(fMRI)技术,探讨轻度认知功能损害(MCI)患者的脑默认活动网络(DMN)是否存在异常及其可能的神经机制.方法 对20名遗忘型MCI老年患者和25名正常老年人进行简易智能状态检查(MMSE)、听觉词语学习测验(AVLT)和静息状态脑功能成像.利用低频振幅(ALFF)算法,观察MCI患者相对于正常老年人ALFF增强及减弱的区域.结果 MMSE和AVLT测试结果显示MCI患者与正常老年人比较,记忆功能损害较明显,主要以情景记忆的短延迟回忆[(2.4±1.7)分与(6.6±1.4)分,t=3.70,P＜0.01]和长延迟回忆[(2.1±1.6)分与(6.7±1.5)分,t=4.16,P＜0.01]损害为主.静息状态fMRI结果显示与正常老年人比较,MCI患者与情景记忆密切相关的海马、海马旁回和侧颞叶皮层等脑区的ALFF减弱(t=2.58、2.43、1.75,均P＜0.01),颞顶交界和顶下小叶的ALFF增强(t=3.14、2.77,均P＜0.01).结论 MCI患者静息状态DMN与情景记忆密切相关的脑区结点活动强度存在异常,与正常老年人比较,大多活动减低,但是部分区域活动增强,提示MCI患者脑内可能存在代偿机制.

Abstract：

Objective To explore the activity and its possible neural mechanism of brain default mode network by using resting state functional magnetic resonance imaging (fMRI) in patients with mild cognitive impairment (MCI). Methods The 20 amnestic MCI patients and 25 healthy controls were included in this study, and all subjects underwent mini-mental state examination (MMSE), auditory verbal learning test (AVLT) and fMRI. The data were analyzed by amplitude of low frequency fluctuation (ALFF), and the enhanced and weakened regions of ALFF were observed and compared in both MCI patients and healthy controls. Results MMSE and AVLT tests showed that the memory function was seriously impaired in MCI patients compared with healthy controls, which is based on the short and long delayed episodic memory impairment (2.4±1.7 vs. 6.6±1.4, t=3.70, P＜0.01; 2.1±1.6 vs. 6.7±1.5, t=4.16, P＜0.01). The resting state fMRI showed that MCI patients had significant decreases of ALFF in hippocampal formation, parahippocampal cortex and lateral temporal cortex as compared with health controls (t=2.58, 2.43 and 1.75, all P＜0.01), which were closely relevant to the episodic memory. And they had significant increases in temporal-parietal joint and inferior parietal lobule (t=3.14 and 2.77, both P＜0.01). Conclusions MCI patients show significant decreased active intensity of some DMN nodes that is related to episodic memory in resting state. Increased active intensity in MCI patients would be some type of compensation.