治疗前男性精神分裂症内囊前肢的DTI研究

目的：应用磁共振扩散张量成像（DTI）探讨男性精神分裂症患者治疗前两侧内囊前肢神经纤维束的微观结构改变。方法：对13例治疗前（病程〈5年）的男性精神分裂症患者（病例组）和11例年龄相匹配的男性健康志愿者（对照组）行DTI检查,在12个方向施加扩散梯度磁场,采用小兴趣区（ROI）法测量并比较两组受试者内囊前肢各向异性分数（FA）值和表观扩散系数（ADC）值的差异。结果：病例组左、右侧内囊前肢的FA值分别为0.587±0.034和0.620±0.042,ADC值分别为（7.349±0.414）和（7.359±0.340）×10-4mm2/s,对照组左、右侧内囊前肢的FA值分别为0.627±0.032和0.639±0.045,ADC值分别为（7.186±0.302）和（7.243±0.389）×10-4mm2/s。病例组左侧内囊前肢FA值低于对照组,差异有显著性意义（t=2.297,P〈0.05）,两组右侧内囊前肢FA值和双侧内囊前肢ADC值的差异均无显著性意义（P〉0.05）。结论：治疗前男性精神分裂症患者白质微观结构发生改变,提示左侧丘脑与前额叶、扣带回前部相互联系的白质功能障碍,可以解释男性精神分裂症的一些临床症状和认知缺陷。     

DTI各向异性分数与椭球面积比在儿童特发性全面性癫痫中的比较研究

【摘要】目的：探讨DTI各向异性分数（FA）和椭球面积比（EAR）在特发性全面性癫痫（IGE）中的诊断价值。方法：根据脑电图对发作间期痫样放电（IED）的定侧结果,将33例IGE患儿分为3组,IGE-A组15例（双侧IED）,IGE-B组9例（左侧IED）,IGE-C组9例（右侧IED）。将32例健康志愿者纳入对照组（NC）,并根据年龄、性别分别与A、B、C组相匹配的方法,进一步分为NC-A组、NC-B组和NC-C组,显示阈值为50个体素（Px）。结果：IGE-A和NC-A组比较,FA和EAR异常分布最大区域为左侧半球额叶和颞叶脑白质,EAR异常还见于右中央颞区（222 Px）、顶叶（198 Px）、脑下回（126 Px）、中央后回（125 Px）等右侧大脑半球白质区域。与NC-B组比较,IGE-B组的FA和EAR异常分布区位于左侧大脑白质梭状回和枕叶,此外左额叶（65Px）白质内有少量EAR异常区域。IGE-C与NC-C组比较,FA和EAR异常改变均位于左侧大脑半球,EAR异常区的体素簇范围较FA体素簇大（169 vs. 50 Px）,EAR图还显示了左侧颞叶（123 Px）、左侧颞中回（112 Px）和颞上回（111 Px）等部位白质及灰质的异常改变。结论：EAR和FA均可反映IGE脑白质异常,EAR比FA更敏感,能发现更多白质异常区域,可用于人类脑部病变的研究。     

静息态fMRI评估职业性噪声聋患者脑功能变化

目的：探讨职业性噪声聋（NIHL）患者的静息态功能磁共振成像（rs-f MRI）低频振荡振幅（ALFF）变化,以评估其静息态脑功能变化。方法：选择42例NIHL伴耳鸣患者,分为轻度组27例,中重度组15例;同期选择健康志愿者30例为对照组。3组均接受结构像T1WI 3D-FSPGR和rs-f MRI扫描。比较分析3组ALFF值,并将3组差异脑区的ALFF值与听力水平及噪声暴露时间行Pearson分析。结果：3组间右侧颞上回、右侧额下回、右侧角回ALFF值差异均有统计学意义（均P<0.01）。事后组间两两比较：轻度组与对照组相比,右侧颞上回ALFF值增加（P<0.001）,右侧角回ALFF值减少（P=0.031）;中重度组与对照组相比,右侧额下回ALFF值升高（P=0.001）,右侧角回ALFF值降低（P<0.001）;中重度组与轻度组相比,右侧额下回ALFF值增加（P=0.008）,右侧颞上回ALFF值降低（P=0.002）。相关性分析：右侧颞上回、右侧角回ALFF值与听力水平均呈显著负相关（均P<0.05）,右侧额下回ALFF值与听力水平呈显著正相关（P<...     

强迫症患者脑部白质异常的磁共振扩散张量成像研究

目的 运用磁共振扩散张量成像技术,探索强迫症患者脑部白质异常的部位.方法 对15例强迫症患者和15例年龄、性别及文化程度相匹配的健康志愿者,分别行脑部DTI扫描.选择双侧眶额叶白质、顶叶白质、扣带束、上纵束、内囊前肢、丘脑后辐射以及胼胝体嘴、胼胝体膝、胼胝体压部作为感兴趣区,分别测量以上部位的FA值进行统计学分析,并与强迫症症状严重性进行相关性分析.结果 与正常对照组相比,强迫症组右侧前扣带回、胼胝体嘴部的FA值降低(P<0.05),左侧前扣带回及右侧前额叶的FA值升高(P<0.05).结论 本研究发现强迫症患者存在多个脑白质区的结构异常,以上部位的异常可能在强迫症的发病中起重要作用.     

肌萎缩侧索硬化症基于体素的形态测量扩散张量分析

目的 利用基于体素的形态测量学(VBM)及基于体素的扩散张量分析评价肌萎缩侧索硬化症(ALS)患者的脑灰质、白质体积及各向异性分数(FA)值的改变.方法 选取39例确诊或拟诊为ALS的患者(ALS组)及39名健康成年人(对照组)进行常规MR扫描及神经心理学评估,并采集3D快速扰相梯度回波(fast spoiled gradient echo,FSPGR)序列T_1WI和DTI数据.对3D T_1结构像进行配准、分割、平滑后,采用VBM分析,计算分割后的脑灰质、白质及脑脊液的体积.选取76名健康志愿者进行DTI,对原始图像进行后处理,制作FA模版,将ALS组和对照组受试者的FA图配准在所创建的FA模版上,测量FA值.统计方法采用协方差分析,因性别完全匹配,故对于VBM,年龄及全脑总体积作为协变量,而对于基于体素的扩散张量分析,仅年龄作为协变量,P＜0.01(未校正),相连像素＞20个的脑区为有差异的脑区.结果 全脑体积分析显示两组受试者的全脑灰质体积、全脑白质体积、全脑体积及脑灰质分数之间差异无统计学意义,但ALS患者的白质分数(0.29±0.02)小于健康对照组(0.30±0.02)(P=0.003).与健康对照组比较,ALS患者局部灰质体积减少脑区主要位于双侧额上回及中央前回,右侧额中回及颞中、下回,左侧枕上回、楔叶及左侧岛叶,ALS患者局部白质体积减少脑区主要位于胼胝体膝部,双侧额内侧回、旁中央小叶及岛叶,右侧额上回及额中回、左侧中央后回.ALS患者双侧扣带回及海马旁回FA值较对照组减低.结论 ALS并不是单纯的运动神经元病,是一种多系统受累的疾病,基于体素的扩散张量分析对于怀疑认知功能障碍的患者海马旁回及扣带回白质FA值变化的检出具有一定的潜在价值.     

成年早期首发精神分裂症患者脑皮层形态学研究

目的 采用基于体素的形态学分析(VBM)和基于表面的形态学分析(SBA)相结合的分析方法,探讨成年早期首次发病精神分裂症患者脑皮层改变区域,并寻找与精神症状相关的皮层改变脑区.方法 依据入组标准,纳入成年早期首次发病精神分裂症患者25例,招募25名健康志愿者为对照组,进行全脑磁共振扫描,获取3D脑结构图像,通过VBM8计算脑皮层体积,通过FreeSurfer软件计算脑皮层厚度与表面积,分别比较患者组和正常对照组间的差异,并将有差异脑区的皮层与PANSS评分(总评分、阳性症状评分、阴性症状评分及一般病理评分)进行相关性分析.结果 患者组左侧额叶直回、中央前回、颞中回、顶上小叶及右侧额上回、颞中回、颞上回、海马旁回、楔叶皮层体积与正常对照组相比减少,差异有统计学意义(P＜0.05);患者组左半球中的舌叶、颞下回、额中回后部及右半球中的颞下回、中央旁小叶、纺锤体、额上回、额中回后部皮层厚度与正常对照组相比,差异有统计学意义(P＜0.05);患者组皮层表面积与正常对照组比较,差异无统计学意义.左半球中额中回后部皮层厚度与PANSS阴性评分、PANNS总评分呈负相关(P＜0.05);右半球中额上回皮层厚度与PANSS阴性评分呈负相关(P＜0.05).结论 成年早期首次发病精神分裂症患者存在多个脑区灰质体积及皮层厚度异常,且有部分脑区的皮层厚度与患者精神症状严重程度相关.     

椎间盘源性下腰痛患者静息态fMRI局部一致性研究

目的：应用静息态fMRI（rs-fMRI）局部一致性（ReHo）方法,观察椎间盘源性下腰痛（DLBP）患者各脑区ReHo值的改变。方法：对25例DLBP患者（DLBP组）及20例健康志愿者（对照组）行rs-fMRI扫描,数据行组内和组间比较,对DLBP组有差异脑区的ReHo值与患者病程、视觉模拟评分（VAS）行相关分析。结果：与对照组比较,DLBP组右侧背外侧额上回、右侧内侧额上回及眶部额中回、前扣带回、右侧岛叶、右侧颞上回、左侧枕中回ReHo值显著升高,右侧楔前叶、后扣带回、左侧颞中回、左侧枕下回、双侧小脑后叶、右侧小脑扁桃体、右中央后回、右侧舌回及梭状回ReHo值显著降低（均P<0.05）。DLBP组右侧额中回ReHo值的增加与病程呈负相关（r=-0.577,P<0.05）;DLBP组差异脑区ReHo值与VAS评分之间尚未发现显著相关性。结论：DLBP患者存在多个脑区ReHo值升高或降低的双向性变化,涉及疼痛感觉、情绪、认知、运动及默认网络的重要集散点等,可能导致机体对疼痛相关的感觉、记忆等信息的加工整合减低,且DLBP可能与患者的负性情绪产生增多、疼痛调节失衡相关。     

急性一氧化碳中毒脑损伤的磁共振扩散张量成像

目的：利用磁共振扩散张量成像(DTI )评估急性一氧化碳(CO)中毒患者的脑结构损伤情况。方法25例急性(5.0 d±1.44 d) CO 中毒患者和37例性别、年龄、利手、受教育程度匹配的健康志愿者进行 DTI 扫描,获得扩散张量纤维束成像(DTT)图像,并分别测量双侧小脑半球(齿状核)、黑质、海马、额叶白质(侧脑室前角前下方、侧脑室体部上方)、尾状核头、苍白球、丘脑、内囊前肢、内囊后肢、枕叶白质(视中枢)、顶叶白质(侧脑室体部上方)及胼胝体膝部、压部共26个感兴趣(ROI)的各向异性分数(FA)值和表观扩散系数(ADC)值,进行组间配对 t 检验。结果病患组双侧苍白球、双侧内囊前肢、双侧黑质、右侧小脑、左侧额叶下部白质、右额叶上下部白质、胼胝体膝部的 FA 值显著低于对照组(P <0.05)。病患组右侧黑质、左侧苍白球的 ADC 值显著降低(P <0.05),病患组右额叶上下部白质及双侧枕叶白质 ADC 值显著升高(P <0.05)。结论急性 CO 中毒患者广泛脑微结构受损,提示脑微结构的原发损伤可能是 CO 中毒迟发性脑病潜在的病理生理基础。     

磁共振扩散张量成像在颈髓病变中的应用

目的：探讨磁共振扩散张量成像（DTI）技术在颈髓病变诊断中的临床应用。方法：应用1.5T磁共振机器对39例颈髓病变患者和15例健康志愿者行MRI常规和DTI检查,测定病变区和对照部位的FA值、ADC值并进行对照分析,并重建白质纤维束图。结果：健康志愿者颈髓的FA值为0.66±0.06,ADC值为（0.96±0.14）×10^-3mm^2/s。颈椎病病例FA值为0.47±0.05、ADC值为（1.16±0.28）×10^-3mm^2/s;与对照组统计学分析FA值明显降低（P〈0.01）,ADC值明显增高（P〈0.01）。颈髓急性损伤病例FA值为0.38±0.08、ADC值为（0.89±0.25）×10^-3mm^2/s;与对照组统计学分析FA值明显降低（P〈0.01）,ADC值与对照组无明显差异（P=0.130〉0.05）。颈髓炎症：FA值为0.40±0.06、ADC值为（1.25±0.40）×10^-3mm^2/s;与对照组统计学分析FA值明显降低（P〈0.01）,ADC值明显增高（P〈0.01）。所有病例通过DTI技术成功显示了白质纤维束在病变区变形、移位及中断等改变。结论：DTI可以探测到颈髓病变中常规MR未能发现的病灶;白质纤维束成像可以显示白质束的受损情况。     

抑郁症患者脑白质纤维的各向异性变化

目的：探讨MRI DWI上抑郁症患者脑白质纤维的各向异性特征。方法：对9例抑郁症患者以及与患者组年龄、性别相匹配的10例志愿者（对照组）行MR扩散张量成像（DTI）。记录额叶、颞叶、枕叶和胼胝体白质的各向异性分值（FA值）。结果：抑郁症患者左右额叶上中下部、左右颞叶、胼胝体压部的脑白质FA值均低于对照组,差异有显著性意义（P〈0.05）。结论：抑郁症患者的额叶和颞叶的白质纤维束FA值比正常人低,而且左右侧不对称。     

基于体素的遗忘型轻度认知障碍和轻度阿尔茨海默病全脑白质MR扩散张量成像分析

目的 采用基于体素的分析(VBA)方法研究遗忘型轻度认知障碍(aMCI)患者和轻度阿尔茨海默病(AD)患者全脑白质微观结构改变的特点及其与灰质萎缩模式的关系.方法 选取33例aMCI患者(aMCI组)、32例轻度AD患者(轻度AD组)和31名正常老年人(健康对照组),对全脑进行3.0 T DTI及三维快速扰相梯度反转回波(3DFSPGR)脉冲序列扫描.采用统计参数图(SPM)5软件对被试者的结构图像及各向异性(FA)图进行预处理,然后采用t检验对aMCI组、轻度AD组和正常对照组的全脑灰质体积及FA值进行基于体素的统计学比较,计算出有统计学意义的脑区.结果 与正常对照组比较,aMCI组的双侧额颞叶和左侧枕叶白质、左侧扣带前部、左侧顶下小叶、右侧脑室三角区外上方白质的FA值减低;轻度AD组的双侧额颞枕叶、海马旁白质、扣带前部、胼胝体、侧脑室三角区旁白质、顶下小叶、左侧颞于、左侧丘脑、右侧楔前叶FA值减低.基于体素的形态测量学(VBM),分析发现,aMCI患者组左侧海马、海马旁回、舌回、颞上回,双侧岛叶、颞中回出现了灰质萎缩;轻度AD患者组双侧海马、海马旁回、杏仁核、丘脑、额叶、颞叶、顶叶、枕叶皮质出现了灰质萎缩.aMCI与轻度AD患者组全脑白质FA值减低的模式与灰质萎缩模式不同.aMCI组与轻度AD组比较未发现具有统计学意义的FA值减低脑区.aMCI、轻度AD患者组全脑白质FA值与简易智能精神状态检查量表(MMSE)评分没有相关性.结论 基于体素的MR DTI全脑白质分析能够较全面、客观地揭示aMCI、轻度AD的脑白质损害的模式.aMCI、轻度AD患者白质损害的模式与灰质不同,提示脑白质病变是多种病理机制导致的.aMCI患者向轻度AD进展过程中,脑白质各向异性改变不显著,脑白质FA值的改变可能无法反映患者认知功能障碍的严重程度.

Abstract：

Objective To evaluate the microstructural integrity of white matter (WM) in patients with amnestic mild cognitive impairment (aMCI) and mild Alzheimer's disease (AD) using voxel-based analysis (VBA), and investigate the relationship between WM abnormalities and gray matter(GM) atrophy.Methods Thirty-three cases with aMCI, 32 cases with mild AD and 31 normal aging volunteers as control subjects were scanned on a 3.0 T MR system using diffusion tensor imaging (DTI) and three-dimensional spoiled gradient-recalled(3DSPGR) sequences. Fractional anisotropy (FA) maps and morphological images were preprocessed by SPM5 and voxel-based comparisons between the 2 patient groups and the control group were performed by t test. Results Relative to the control group, patients with aMCI showed significantly reduced FA value in bilateral frontal, temporal and left occipital WM, left anterior part of cingulum, left inferior parietal lobule, and the W M adjacent to the triangular part of the right lateral ventricle(k≥20 voxels).In mild AD,significantly reduced FA value was found in bilateral hippocampal,inferior parietal lobular,frontal,temporal,and occipital WM,bilateral corpus callosum,anterior part of cingulums,the WM adjacent to the triaangular part of the bilateral lateral ventricles,left temporal stem,left thalamus,right precuneus(k≥20 voxels).Significantly reduced GM volume was found in left hippocampus,parahippocampal gyrus,lingual gyrus and superior temporal gyrus,bilateral insulae and middle temporal gyri in aMCl group whencompared with control group(k≥50 voxels).In mild AD,significantly reduced GM volume was found in bilateral hippoeampi,parahippocampal gyri,amygdalae,thalami,temporal,parietal,frontal,occipital cortex(k≥50 voxels).The pattern of areas with reduced FA differs;from that of the GM volumetric reduction.No areas with significantlv reduced FA was detected in aMCl compared with mild AD. There was no significant correlation between FA value of WM in patient groups and Mini-Mental State Examination(MMSE)scores.Conclusions Voxel-based MRI DTI analysis of whole brain white matter can objectively reveal widespread white matter abnormalities in early-stage AD.The difierence between WM FA reduction pattern and GM volumetric reduction pattern indicates that the pathological WM changes in earlyslage AD were caused by multiple mechanisms. FA did not vary significantly in patients pr0gressing from aMCI to mild AD and can hardly reflect the severitv of cognitive function damage in these patients.     

Changes in cerebellar functional connectivity and anatomical connectivity in schizophrenia: a combined resting-state functional MRI and diffusion tensor imaging study

Purpose:

To examine the functional and anatomical connectivity of the cerebellum and their relationship in schizophrenia through resting‐state functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI).

Materials and Methods:

Ten subjects with schizophrenia and 10 healthy controls underwent resting‐state fMRI and DTI. Left and right cerebellar seed regions were used in a voxel‐wise functional connectivity analysis of the cerebellum. Fractional anisotropy (FA) was measured to assess white matter integrity of the middle cerebellar peduncle (MCP) and superior cerebellar peduncle (SCP). Differences in functional connectivity and FA values between the two groups were determined by two‐sample t‐tests. The relationship between functional connectivity and FA values in both groups were assessed using Pearson s correlation.

Results:

Decreased functional connectivity to the left middle temporal gyrus, bilateral middle cingulate cortex, right paracentral lobule, right thalamus, and bilateral cerebellum were found in subjects with schizophrenia when compared to healthy controls; while decreased FA values in the left SCP were found in subjects with schizophrenia compared to healthy controls. Significant correlation was observed between the functional connectivity of the left cerebellum‐right paracentral lobule and right cerebellum‐right thalamus and the FA values of the MCP in healthy controls.

Conclusion:

Findings of this multi‐modal imaging study support functional and anatomical connectivity abnormalities and the role of the cerebellum in schizophrenia. They also indicate the need for further investigation regarding the relationship between functional and anatomical connectivity and its role in neuropathophysiology. J. Magn. Reson. Imaging 2011;. © 2011 Wiley Periodicals, Inc.     

Uncinate fasciculus fiber tracking in mesial temporal lobe epilepsy. Initial findings

In temporal lobe epilepsy (TLE) due to hippocampal sclerosis (HS), ictal discharge spread to the frontal and insulo-perisylvian cortex is commonly observed. The implication of white matter pathways in this propagation has not been investigated. We compared diffusion tensor imaging (DTI) measurements along the uncinate fasciculus (UF), a major tract connecting the frontal and temporal lobes, in patients and controls. Ten right-handed patients referred for intractable TLE due to a right HS were investigated on a 1.5-T MR scanner including a DTI sequence. All patients had interictal fluorodeoxyglucose PET showing an ipsilateral temporal hypometabolism associated with insular and frontal or perisylvian hypometabolism. The controls consisted of ten right-handed healthy subjects. UF fiber tracking was performed, and its fractional anisotropy (FA) values were compared between patients and controls, separately for the right and left UF. The left-minus-right FA UF asymmetry index was computed to test for intergroup differences. Asymmetries were found in the control group with right-greater-than-left FA. This asymmetrical pattern was lost in the patient group. Right FA values were lower in patients with right HS versus controls. Although preliminary, these findings may be related to the preferential pathway of seizure spread from the mesial temporal lobe to frontal and insulo-perisylvian areas.     

肝硬化患者基于体素的全脑扩散张量成像研究

目的：探讨基于体素的扩散张量成像（DTI）对无肝性脑病肝硬化（non-HE）到轻微肝性脑病（MHE）进展的潜在应用价值。方法：对45例无明显肝性脑病症状的肝硬化患者和27例年龄、性别相匹配的健康志愿者（对照组）进行常规MRI和DTI检查。采用神经心理学测试中的数字连接实验-A（NcT-A）和数字符号实验（DST）对受试者认知功能进行评估,根据测试结果将肝硬化患者分为MHE组和non-HE组;采用基于体素的sPM8软件对三组受试者的平均扩散率（MD）图及各向异性分数（FA）图进行ANOVA分析,观察MHE和non-HE组MD值和FA值发生改变的脑区。结果：三组间MD值差异脑区主要位于额叶、颞叶、顶叶区;与non-HE组相比,MHE组右侧颞上／中回、右侧角回、右侧顶叶MD值升高。三组间FA值差异脑区主要位于胼胝体、前扣带回、顶叶及额叶区;与non-HE组相比,MHE组在胼胝体及前扣带皮层的FA值减低。结论：基于体素的DTI技术可观察无明显肝性脑病症状的肝硬化患者脑结构的异常;肝硬化患者存在间质性脑水肿,且与疾病进展有关。     

Gray and white matter changes in Alzheimer's disease: a diffusion tensor imaging study

PURPOSE: To investigate microstructural changes in cortical and white matter pathways in patients with Alzheimer's disease using diffusion tensor imaging (DTI). MATERIALS AND METHODS: Measures of mean diffusivity (MD) and fractional anisotropy (FA) were compared in the brains of 13 Alzheimer's disease (AD) patients and a group of 13 aged-matched control participants employing an optimized DTI technique involving a fully automated, voxel-based morphometric (VBM) analysis. RESULTS: After rigorous control for anatomical variation and confounding partial volume effects, we found significantly elevated MD measures within the hippocampus, amygdala, and medial temporal, parietal, and frontal lobe gray matter regions in the AD participants. The largest number of pixels with increased MD was localized bilaterally, within the posterior cingulate gyrus. The FA was significantly reduced within the thalamus, parietal white matter, and posterior limbs of the internal capsule, indicating significant involvement of corticothalamic and thalamocortical radiations. CONCLUSION: This study demonstrates that rigorous VBM analysis of DTI data can be used to investigate microstructural changes in cortical, subcortical, and white matter regions in AD.     

复发缓解型多发性硬化患者扣带束白质完整性与扣带皮质灌注研究

目的采用扩散张量成像(DTI)及三维伪连续动脉自旋标记(3D-pCASL)技术探讨复发缓解型多发性硬化(RRMS患者扣带束微结构与扣带皮层灌注改变及其与临床评分的相关性。资料与方法对24名RRMS患者(MS组)及26名体检者(对照组)行临床扩展残疾状态量表(EDSS)及神经心理学量表评分。所有研究对象行DTI及3D-pCASL扫描,测量左、右扣带束的各向异性分数(FA)值与平均扩散率(MD)值,以及扣带皮层8个亚区脑血流量(CBF)值,并评估其与EDSS及神经心理学评分之间的相关性。结果与对照组相比,MS组患者左侧前扣带皮层尾部、右侧后扣带皮层和峡部CBF值以及右侧扣带皮层平均CBF值均显著减低(P<0.05)。MS组双侧扣带束扣带部(CGC)FA值降低,MD值升高;右侧扣带束海马部(CGH)FA值降低,双侧CGH部MD值升高(P均<0.05)。符号数字转换测验(SDMT)评分与左侧前扣带皮层尾部、右侧后扣带皮层及扣带皮层峡部CBF值、双侧CGC部FA值以及与右侧CGH部MD值存在相关性(r=0.391、0.346、0.307、0.389、0.374、-0.371,P均<0.05)。汉密顿抑郁量表评分与双侧CGC部FA值及MD值存在相关性(r=-0.296、-0.338、0.324、0.343,P均<0.05)。控制年龄、性别及受教育程度后,SDMT评分与双侧CGC部FA值仍显著相关。结论 RRMS患者扣带束及扣带皮层出现改变,与患者认知功能障碍和抑郁相关,可能体现出扣带回的功能异质性。     

Cerebral asymmetry in patients with schizophrenia: A voxel‐based morphometry (VBM) and diffusion tensor imaging (DTI) study

Purpose:

To evaluate the differences in gray‐ and white‐matter asymmetry between schizophrenia patients and normal subjects.

Materials and Methods:

Forty‐eight right‐handed patients with chronic schizophrenia (24 males and 24 females) and 48 right‐handed age‐ and sex‐matched healthy controls (24 males and 24 females) were included in this study. The effects of diagnosis on gray‐matter volume asymmetry and white‐matter fractional anisotropy (FA) asymmetry were evaluated with use of voxel‐based morphometry (VBM) and voxel‐based analysis of FA maps derived from diffusion tensor imaging (DTI), respectively.

Results:

The mean gray‐ and white‐matter volumes were significantly smaller in the schizophrenia group than in the control group. The voxel‐based morphometry (VBM) showed no significant effect of diagnosis on gray‐matter volume asymmetry. The voxel‐based analysis of DTI also showed no significant effect of diagnosis on white‐matter FA asymmetry.

Conclusion:

Our results of voxel‐based analyses showed no significant differences in either gray‐matter volume asymmetry or white‐matter FA asymmetry between schizophrenia patients and normal subjects. J. Magn. Reson. Imaging 2010;31:221–226. © 2009 Wiley‐Liss, Inc.     

多发性硬化的正常表现脑白质的DTI定量

目的：应用磁共振弥散张量成像（DTI）技术，定量研究多发性硬化（MS）患者在常规磁共振上表现正常的脑白质（NAWM），以及探讨其相关的微观病理改变。材料和方法：采用3．0T磁共振仪，对34例Ms患者和25例性别年龄相匹配的正常志愿者均进行DTI检查。分别测量MS组和对照组的9个不同部位脑白质的平均弥散率（MD）和部分各向异性指数（FA值），这9个部位包括胼胝体膝部、体部、压部、内囊后肢、侧脑室旁白质、额叶白质、顶叶白质、枕叶白质以及小脑中脚。比较两组NAWM之间的MD和FA值是否存在差异。结果：MS组的NAWM的MD值均高于对照组（P〈0．05），以胼胝体体部、内囊、侧脑室旁及额叶白质、顶叶白质、枕叶白质更为显著（P〈0．01）；MS组的FA值与对照组比较，胼胝体体部、顶叶白质、额叶白质、枕叶白质及内囊、侧脑室旁发现明显降低（P〈0．05），以后4个部位更为显著（P〈0．01），而胼胝体膝部、压部和小脑结合臂有降低趋势，但无统计学意义。结论：应用DTI定量研究可以探测到多发性硬化的NAWM所出现的微观病理改变，表现为水分子的平均弥散幅度明显升高，以幕上明显，并且胼胝体体部、内囊后肢等白质纤维明显失去正常的方向性。DTI在对白质损伤程度的量化评估中具有重要的价值。