老年痴呆患者脑白质结构的扩散加权成像研究

目的 应用扩散加权成像(diffusion weighted imaging,DWI)阐明阿尔茨海默病（AD）脑白质微结构平均弥散系数(ADC)的变化,进一步探讨脑白质微结构改变与认知功能损害之间的关系。方法 选取AD组及对照组各30例。所有受检者均进行神经科查体和简易智能精神状态量表(MMSE)测试,对常规脑部MRI脑白质表现正常的部位行DWI检查,测量不同兴趣区的平均弥散系数（ADC）,选择额叶白质、颞叶白质、顶叶白质、枕叶白质、胼胝体膝部、胼胝体压部5个兴趣区,定量测量ADC值。结果老年痴呆组ADC值与对照组比较,在额叶白质(ADC：t=-0.050,p<0.01)、胼胝体膝部(ADC：t=-0.012,p>O.05)、胼胝体压部(ADC：t=-0.028,p<0.05)、颞叶(ADC：t=-0.062,p<0.01)、顶叶(ADC：t=-0.057,p<0.01)、枕叶(ADC：t=0.000,p>0.05)。老年痴呆组顶叶白质、胼胝体压部、额叶白质的ADC值与简易智能精神状态量表(MMSE)相关,尤其是顶叶白质的ADC值相关更显著(r=-0.867,p<0.01)。结论 老年痴呆的定量DWI分析,有助于评价AD常规MRI检查正常区域的微结构改变。顶叶脑白质ADC值的异常在认知功能损害早期更明显,DWI功能与结构的结合,表明老年痴呆认知功能的衰退与白质微结构密切相关。     

DTI在早产儿脑白质损伤中的应用

目的 探讨扩散张量成像(DTI)在早产儿脑白质损伤中的应用价值.方法 97例早产儿分为脑白质损伤组(48例)和无脑白质损伤组(49例).按胎龄分为早期(28～31周)早产儿22例、中期(32～34周)早产儿35例和晚期(35～36周)早产儿40例;在纠正胎龄36～38周时进行磁共振DTI检查,分析各向异性分数(FA)和表观弥散系数(ADC)的差异.结果 DTI图像显示,无脑白质损伤组双侧大脑半球、小脑和侧脑室等均未见异常.脑白质损伤组DTI图像发现,脑白质软化灶2例,缺氧缺血性脑病2例,蛛网膜下腔出血4例,硬脑膜下出血2例,额叶出血2例,脑出血17例,其他类型的脑损伤19例.脑白质损伤组早期、中期和晚期早产儿胼胝体膝部、胼胝体压部、内囊后肢、内囊前肢和丘脑的FA值均小于无脑白质损伤组(P＜0.05),而两组ADC值比较无统计学差异(P＞0.05).早期早产儿内囊前肢、左侧内囊后肢、胼胝体压部和右侧丘脑FA值低于晚期早产儿,右侧内囊前肢、胼胝体压部和丘脑FA值低于中期早产儿(P＜0.05).早期早产儿内囊后肢和胼胝体压部ADC值高于中期早产儿和晚期早产儿,早期早产儿和中期早产儿胼胝体膝部ADC值高于晚期早产儿(P＜0.05).结论 DTI能够识别早产儿脑白质损伤.     

认知量表联合颅脑磁共振对维持性透析患者认知功能的评价

目的 探讨简易精神状态量表（MMSE）和蒙特利尔认知评估量表（MoCA）联合颅脑磁共振（MRI）弥散加权成像（DWI）/扩散张量成像（DTI）对透析患者认知功能的评估价值。方法 选择2015年5月至2016年5月于安徽医科大学第二附属医院肾内科进行透析的患者65例,采用MMSE和MoCA评估患者认知功能,MRI扫描脑白质区并计算表观弥散系数（ADC）和部分异向性（FA）量化值;根据MoCA结果分为认知正常组（38例）和认知障碍组（27例）,比较两组患者量表评分、ADC值及FA值的差异性。结果 MoCA检出率高于MMSE,差异有统计学意义（χ²=17.725,P=0.001）,且MMSE和MoCA总分呈正相关（r=0.660,P=0.001）。认知障碍组患者MMSE评分的定向力、记忆力、注意力、语言和总分低于认知正常组,而MoCA评分的执行力、注意力、语言、延迟回忆、定向力和总分均低于认知正常组,差异有统计学意义（P<0.05）;额叶和顶叶ADC值高于正常组,额叶、顶叶、胼胝体及侧脑室FA值低于正常组,差异有统计学意义（P<0.05）。结论 多认知量表联合评估可提高透析患者认知障碍的检出率;且存在认知障碍的透析患者主要表现为执行力、定向力、注意力、语言和记忆力的下降,和大脑额叶、顶叶、胼胝体和侧脑室白质的损伤相对应。     

部分脑白质微结构与帕金森病并发认知障碍的相关性分析

目的 探讨额叶白质、上纵束、扣带前束及扣带后束脑白质微结构与帕金森病并发认知障碍的相关性.方法 根据蒙特利尔认知评估量表（MOCA）将76例帕金森病患者分成并发认知障碍组（PDD组）48例和未并发认知障碍组（PD-CogNL组）28例,另选取30例健康者为对照组.分别测量3组额叶白质、上纵束、扣带前束及扣带后束的FA值.结果 PD-CogNL组额叶白质FA值及扣带前束FA值显著低于对照组,PDD组额叶白质FA值及扣带前束FA值显著低于对照组及PDD组,差异均有统计学意义（P＜0.05）.3组上纵束FA值和扣带后束FA值比较差异无统计学意义（P＞0.05）.结论 帕金森病患者并发认知障碍与额叶白质、扣带前束微脑白质结构的改变具有显著关系,其中与扣带前束相关性最加显著,由此通过测定帕金森病患者脑白质微结构的改变来评定其并发认知障碍的程度.     

磁共振成像在肾上腺脑白质营养不良诊断中的应用研究

目的分析磁共振成像在肾上腺脑白质营养不良诊断中的应用价值。方法选择2017年6月至2018年6月来我院神经内科就诊以及住院的10例肾上腺脑白质营养不良患者为研究对象。另外选择10例正常人为对照组,分析结果。结果两侧脑室三角区四周对称性分布长T_1T_2信号影像。在此同时累积到胼胝体压部、两侧病灶相连。少数呈现为蝴蝶翼样表现。随着疾病进展,原有病灶至顶叶白质区域朝向前方累及到基底节、颞叶以及额叶之中。在此同时朝向下方扩展累积到脑干部分。患者病灶呈现为环形强化表现。早期出现病变的顶叶白质明显比朝向远处扩散区域病灶以及正常脑白质NAA/cr以及NAA/Cho比值下降,Cho/Cr比值显著上升,FA以及ADC值最低,P<0.05。邻近位置NAA/cr以及NAA/Cho对比值下降情况比远周更为明显,P <0.05。病变进展区域内的ADC值呈现出了降低趋势,FA为最高。NAA/cr以及NAA/Cho和ADC呈现负相关,和ADC成正相关关系,NAA/cr以及NAA/Cho和FA呈正相关,Cho/cr和FA不存在相关性。结论磁共振成像能够为ALD提供更多的临床诊断依据,另外也可实现动态化监测患者脑白质病变进展情况,DTI能够直接显示出该疾病患者纤维束受累详情,因此值得进一步推广。     

精神分裂症患者脑白质纤维不对称性及结构完整性的 MR 弥散张量成像分析

目的：对精神分裂症患者脑白质纤维不对称性及结构完整性的 MR 弥散张量成像分析精神分裂症患者脑白质纤维束损伤及变化情况。方法选取50例患有精神分裂症的患者,将其作为试验组,再选取50例正常的健康人作为对照组,分别采用 MR 弥散张量成像的检测方法对2组患者进行检测,对比分析2组患者的脑白质含量情况以及重建纤维束的数量情况。结果试验组患者的右侧额叶白质、左侧额叶白质、右侧颞叶白质、左侧颞叶白质等部位的蛋白质含量与正常对照组患者比较,差异统计学无意义（P ＞0．05）。试验组患者的胼胝体、右侧钩束、左侧钩束、右侧扣带、左侧扣带、右侧下纵束、左侧下纵束纤维束的数量明显低于对照组（P ＜0．05）。结论MR 弥散张量成像在分析精神分裂症患者脑白质纤维束损伤过程中应用效果显著,值得广泛推广。     

单相抑郁症患者各脑叶CT检查参数的改变及影像学分析

目的通过各脑叶CT检查参数的改变分析单相抑郁症患者的影像学改变。方法纳入2019年6月至2021年6月绍兴市第七人民医院放射科室接诊的单相抑郁症患者100例为观察组, 同期选取身体检查为健康者100例为对照组, 均给予颅脑CT扫描, 对两组患者各脑叶CT值进行对比分析。结果脑叶CT值:观察组左额叶(40.88±2.01)HU、左颞叶(40.21±3.01)HU均低于对照组(t左额叶=2.94, P=0.004;t左颞叶=3.29, P=0.001), 观察组右额叶(40.09±2.52)HU、右颞叶(44.93±3.03)HU与对照组差异无统计学意义(t右额叶=1.89, P=0.060;t右颞叶=1.89, P=0.060)。两组左右枕叶、顶叶CT值差异无统计学意义(P > 0.05)。观察组脑叶CT值与年龄、Hamilton汉密尔顿抑郁量表(HAMD-24)评分、病程、发作次数的单因素相关分析结果显示, 左、右额叶CT值与年龄(-0.441、-0.211)、病程(-0.445、-0.191)呈负相关(P < 0.05);左、右额叶CT值与HAMD-24评分、发作次数无明...     

认知功能障碍与脑卒中部位的相关性分析

目的探讨脑卒中部位与认知功能障碍之间的关系,观察不同部位脑卒中所致认知功能障碍的特点。方法采用中文版蒙特利尔认知评估量表（MOCA）对100例脑卒中患者进行测试,将脑卒中患者的CT／MRI定位与MOCA的7个分项目（定向力ORT、视空间与执行功能EF、命名NAM、记忆MEM、注意ATT、语言功能包括复述与流畅性LANG、抽象概括ABS）的测试结果进行相关分析。结果（1）100例患者中脑梗死63例,脑出血37例,其中额叶卒中15例,顶叶15例,颞叶12例,枕叶8例,丘脑14例,基底节20例,小脑8例,脑桥8例。额叶、顶叶、颞叶、枕叶、丘脑、基底节卒中与认知功能障碍发生相关（P〈0.05）。枕叶、脑桥卒中与认知功能障碍无关（P〉0.05）。（2）额叶卒中患者认知功能的EF、ORT、MEM、ATT、ABS损害明显;顶叶卒中与认知功能的NAM、MEM、ATT、EF损害有关;颞叶卒中与LANG和EF损害有关,枕叶卒中患者视空间及执行功能（EF）损害明显;丘脑损害语言功能（LANG）受损明显;基底节卒中患者MOCA各分测验均有损害。结论脑卒中患者认知功能障碍的发生与卒中部位有关,不同部位卒中损害认知功能不同。     

新生儿低血糖脑病的MRI特点

目的分析新生儿低血糖脑损伤的磁共振成像(MRI)特点及磁共振弥散加权成像技术(DWI)优势。方法回顾性分析临床诊断为低血糖脑病的25例患儿的磁共振成像常规T1、T2及DWI表现。结果 T1表现异常12例,表现为受累皮质稍高信号,皮层下低信号。T2表现异常17例,表现为受累部位低或高信号,皮髓界限不清。受累部位包括双侧顶枕叶皮质及皮质下白质22例,右侧枕叶皮层6例,左侧颞叶后部皮层下白质2例,胼胝体10例,内囊后肢3例。25例脑损伤患者中24例DWI可见异常。3个月后3例复查MRI,2例为双侧顶枕叶萎缩表现。结论低血糖脑损伤最常见的发病部位为顶枕叶,其他部位也可受累,DWI应作为早期诊断低血糖脑损伤的常规序列。     

正常脑老化过程中中央前、后回白质区ADC值与年龄和性别比的相关性分析

目的 利用MR扩散加权成像(diffusion weighted imaging,DWI)观察中央前回与中央后回(即运动中枢与感觉中枢)白质区表观扩散系数(apparent diffusion coefficient,ADC)值在正常脑老化过程中的年龄、性别相关性分析.方法 120例健康右利手志愿者,按性别及年龄分为女性及男性青年组(≤44岁)和女性及男性中老年组(＞45岁),每组30例.所有志愿者均行颅脑常规磁共振成像[magnetice resonance imaging,MRI)及扩散加权成像(diffusionweighted imaging,DWI)检查,人为确定DWI感兴趣区(ROI为(22 ±2)mm2],感兴趣区选定在白质区,机器自动测出左、右侧中央前回及左、右侧中央后回白质区ADC值数据,分别测量3次取其平均值.比较不同性别、不同年龄组间ADC值差异.分析中央前、后回白质区ADC值与年龄、性别的相关性.结果 相同性别不同年龄组间左、右侧中央前回及左、右侧中央后回白质区ADC值差异均有统计学意义(P＜0.05).青年组女性与男性右侧中央前回白质区ADC值差异有统计学意义(P＜0.05);中老年组女性与男性左侧中央后回白质区ADC值差异有统计学意义(P＜0.05).结论 正常脑老化过程中,左、右侧中央前回及左、右侧中央后回白质区ADC值与年龄呈线性正相关性改变,即随着年龄增长ADC值逐渐增加.青年男性右侧中央前回白质区ADC值大于青年组女性,中老年男性左侧中央后回白质区ADC值大于中老年女性.     

Greater Than Age-Related Changes in Brain Diffusion of HIV Patients After 1 Year

Chronic infection with HIV is associated with neuroinflammation. Prior diffusion tensor imaging (DTI) studies demonstrated increased mean diffusion (MD) and decreased fractional anisotropy (FA) in the white matter (WM) and subcortical brain regions of HIV patients. The current study aims to detect whether there are greater than age-related brain changes in HIV patients after a 1-year follow-up period using DTI. Thirty-nine antiretroviral-stable HIV subjects and 32 HIV-seronegative (SN) controls were evaluated, with neuropsychological tests and DTI, at baseline and after 1 year. MD and FA in the genu and splenium of the corpus callosum and in six other subcortical and white matter regions were evaluated bilaterally. Compared to SN controls, HIV subjects had significantly higher MD in the frontal WM (p = 0.0104) and lower FA in the parietal WM (p = 0.006). After 1 year, HIV subjects showed increase in MD in frontal and parietal WM, putamen, and genu; HIV subjects also showed greater increased genu diffusion than SN controls (p = 0.005). Changes in global cognitive deficit score correlated with changes in MD in the genu and FA in the parietal and frontal WM and putamen (multiple regression, p = 0.0008). Lastly, normal age-dependent changes in frontal WM diffusion and FA in genu and putamen were not observed in HIV subjects. Since increased MD may reflect increased neuroinflammation, our findings suggest greater than normal age-related inflammatory changes in the genu of these HIV patients, which may contribute to the cognitive deficits. Measurements of MD in the genu may be useful for monitoring disease progression in HIV brain infection.     

胼胝体损伤的CT和MRI诊断

目的探讨胼胝体损伤的CT和MRI表现,评价CT和MRI对其诊断价值。方法搜集16例胼胝体损伤CT和MRI表现作回顾性分析,16例均行CT和MRI检查。结果 16例胼胝体损伤中,5例位于体部,5例位于压部,5例累及体部和压部,1例位于膝部;常规MRI上表现为T2WI均为高信号,T1WI为低、等或略低信号,弥散加权像(DWI)对胼胝体损伤具有敏感性,病灶显示高于常规T2WI,极易发现病灶且均表现为高信号。CT检查胼胝体区未见异常密度。12例还合并颅内多处挫伤和血肿。结论胼胝体损伤少见,CT检查难以发现,MRI是最好的影像检查方法 ,胼胝体损伤大多数合并颅内损伤。     

Altered Interhemispheric and Temporal Lobe White Matter Microstructural Organization in Severe Chronic Schizophrenia

Diffusion MRI investigations in schizophrenia provide evidence of abnormal white matter (WM) microstructural organization as indicated by reduced fractional anisotropy (FA) primarily in interhemispheric, left frontal and temporal WM. Using tract-based spatial statistics (TBSS), we examined diffusion parameters in a sample of patients with severe chronic schizophrenia. Diffusion MRI data were acquired on 19 patients with chronic severe schizophrenia and 19 age- and gender-matched healthy controls using a 64 gradient direction sequence, (b=1300 s/mm²) collected on a Siemens 1.5T MRI scanner. Diagnosis of schizophrenia was determined by Diagnostic and Statistical Manual for Mental Disorders 4th Edition (DSM-IV) Structured Clinical Interview for DSM disorder (SCID). Patients were treatment resistance, having failed to respond to at least two antipsychotic medications, and had prolonged periods of moderate to severe positive or negative symptoms. Analysis of diffusion parameters was carried out using TBSS. Individuals with chronic severe schizophrenia had significantly reduced FA with corresponding increased radial diffusivity in the genu, body, and splenium of the corpus callosum, the right posterior limb of the internal capsule, right external capsule, and the right temporal inferior longitudinal fasciculus. There were no voxels of significantly increased FA in patients compared with controls. A decrease in splenium FA was shown to be related to a longer illness duration. We detected widespread abnormal diffusivity properties in the callosal and temporal lobe WM regions in individuals with severe chronic schizophrenia who have not previously been exposed to clozapine. These deficits can be driven by a number of factors that are indistinguishable using in vivo diffusion-weighted imaging, but may be related to reduced axonal number or packing density, abnormal glial cell arrangement or function, and reduced myelin.     

Assessing white matter integrity as a function of abstinence duration in former cocaine-dependent individuals

Current cocaine-dependent users show reductions in white matter (WM) integrity, especially in cortical regions associated with cognitive control that have been associated with inhibitory dysfunction. A key question is whether these white matter differences are present following abstinence from drug use. To address this, WM integrity was examined using diffusion tensor imaging (DTI) obtained on 43 cocaine abstinent patients (abstinence duration ranged between five days and 102 weeks) and 43 non-using controls. Additionally, a cross-sectional comparison separated the patients into three groups (short-term, mid-term and long-term) based upon duration of cocaine abstinence. The 43 cocaine abstinent patients showed lower fractional anisotropy (FA) in the left anterior callosal fibers, left genu of the corpus callosum, right superior longitudinal fasciculus, right callosal fibers and the superior corona radiata bilaterally when compared against non-using controls. Higher FA in the cocaine abstinent patients was observed in the splenium of the corpus callosum and right superior longitudinal fasciculus. Differences between the cocaine abstinent groups were observed bilaterally in the inferior longitudinal fasciculus, right anterior thalamic radiation, right ventral posterolateral nucleus of the thalamus, left superior corona radiata, superior longitudinal fasciculus bilaterally, right cingulum and the WM of the right precentral gyrus. The results identified WM differences between cocaine abstinent patients and controls as well as distinct differences between abstinent subgroups. The findings suggest that specific white matter differences persist throughout abstinence while other, spatially distinct, differences discriminate as a function of abstinence duration. These differences may, therefore, represent brain changes that mark recovery from addiction.     

White Matter Integrity is Associated with Treatment Outcome Measures in Cocaine Dependence

Cocaine dependence is associated with white matter impairments that may compromise cognitive function and hence drug users'' abilities to engage in and benefit from treatment. The main aim of this study was to assess whether white matter integrity correlates with treatment outcome measures in cocaine dependence. Diffusion tensor imaging (DTI) was used to assess the white matter (WM) of 16 treatment-seeking cocaine-dependent patients before 8 weeks of therapy. The measures for treatment outcome were longest self-reported duration of continuous cocaine abstinence, percent of urine screens negative for cocaine, and duration (weeks) of treatment retention. Correlations between treatment outcome measures and DTI parameters (fractional anisotropy (FA), longitudinal eigenvalue (λ₁), perpendicular eigenvalue (λ_T), and mean diffusivity (MD)) were analyzed. Longest self-reported abstinence from cocaine and percent of cocaine-negative urine samples during treatment positively correlated with FA values and negatively correlated with λ₁, λ_T, and MD values across extensive brain regions including the corpus callosum, frontal, parietal, temporal, and occipital lobes, and cerebellum. The findings of an association between better WM integrity at treatment onset and longer abstinence suggest that strategies for improving WM integrity warrant consideration in developing new interventions for cocaine dependence.     

Alcohol consumption and premotor corpus callosum in older adults

Heavy alcohol consumption is toxic to the brain, especially to the frontal white matter (WM), but whether lesser amounts of alcohol negatively impact the brain WM is unclear. In this study, we examined the relationship between self-reported alcohol consumption and regional WM and grey matter (GM) volume in fifty-six men and thirty-seven women (70+- 7years) cognitively intact participants of the Baltimore Longitudinal Study of Aging (BLSA) with no history of alcohol abuse. We used regional analysis of volumes examined in normalized space (RAVENS) maps methodology for WM and GM segmentation and normalization followed by voxel based morphometry (VBM) implemented in SPM8 to examine the cross-sectional association between alcohol consumption and regional WM (and, separately, GM) volume controlling for age, sex, smoking, blood pressure and dietary thiamine intake. WM VBM revealed that in men, but not in women, higher alcohol consumption was associated with lower volume in premotor frontal corpus callosum. This finding suggests that even moderate amounts of alcohol may be detrimental to corpus callosum and white matter integrity.     

胼胝体变性的CT表现

目的：研究分析胼胝体变性（MBD）患者的临床表现和影像学特征与诊断方法。方法：4例长期酗酒男性MBD患者,均经CT检查。结果：3例CT可见胼胝体膝部和压部对称性低密度病灶。1例CT表现为胼胝体膝部、体部、压部对称性低密度病灶。结论：CT为诊断胼胝体变性的主要手段,以胼胝体膝部、压部对称性病灶为其主要异常表现。     

Reduced anterior corpus callosum white matter integrity is related to increased impulsivity and reduced discriminability in cocaine-dependent subjects: diffusion tensor imaging.

Brain imaging studies find evidence of prefrontal cortical dysfunction in cocaine-dependent subjects. Similarly, cocaine-dependent subjects have problems with behaviors related to executive function and impulsivity. Since prefrontal cortical axonal tracts cross between hemispheres in the corpus callosum, it is possible that white matter integrity in the corpus callosum could also be diminished in cocaine-dependent subjects. The purpose of this study was to compare corpus callosum white matter integrity as measured by the fractional anisotropy (FA) on diffusion tensor imaging (DTI) between 18 cocaine-dependent subjects and 18 healthy controls. The Barratt Impulsiveness Scale (BIS-11) and a continuous performance test: the Immediate and Delayed Memory Task (IMT/DMT) were also collected. Results of the DTI showed significantly reduced FA in the genu and rostral body of the anterior corpus callosum in cocaine-dependent subjects compared to controls. Cocaine-dependent subjects also had significantly higher BIS-11 scores, greater impulsive (commission) errors, and reduced ability to discriminate target from catch stimuli (discriminability) on the IMT/DMT. Within cocaine dependent subjects there was a significant negative correlation between FA in the anterior corpus callosum and behavioral laboratory measured impulsivity, and there was a positive correlation between FA and discriminability. The finding that reduced integrity of anterior corpus callosum white matter in cocaine users is related to impaired impulse control and reduced ability to discriminate between target and catch stimuli is consistent with prior theories regarding frontal cortical involvement in impaired inhibitory control in cocaine-dependent subjects.     

胼胝体变性的临床及影像特征(附4例分析)

目的 分析胼胝体变性(MBD)患者的临床表现和影像学特征,以加深对本病的认识.方法 对4例MBD 患者的临床表现及影像学资料进行回顾性分析.结果 4例患者均有长期大量饮酒的嗜好,以精神症状、共济失调、痴呆为主要表现;CI与MR 可见胼胝体膝部和压部病灶.CT病灶为低密度,MRI 表现为T1低信号;T2高信号;予大剂量维...