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1.
白质纤维束的弥散张量成像在脑胶质瘤外科的应用   总被引:6,自引:1,他引:5  
目的:探讨MRI弥散张量成像(DTI)显示脑白质纤维束在脑胶质瘤外科的意义。方法:2003年9月至2004年12月,30例脑内肿瘤患者接受术前常规头颅MRI序列检查的同时,进行DTI序列扫描,经后处理得到各向异性分数(FA)图显示脑白质纤维束结构,并进行FA值、图像信号强度及对比度的分析研究。结果:所有病例均成功实现包括DTI序列扫描以及FA图像生成。脑白质纤维束显示为显著的高信号结构;灰质显示为等信号;脑脊液显示为低信号;脑内肿瘤呈类圆形等、低信号灶;肿瘤周围间质水肿区白质纤维束仍能在DTI的FA图上显像。DTI的FA图像对于脑白质纤维束显影的信号对比度明显优于常规的T1W图像。结论:DTI影像可以清晰显示脑白质纤维束的形态结构。结合其他序列的MRI应用于脑胶质瘤的术前诊断,可以准确判别肿瘤和周围脑白质纤维束的毗邻关系,对脑胶质瘤手术方案设计以及术后神经功能障碍的预测与预防具有重要意义。  相似文献   

2.
目的评价DTI诊断中枢神经系统疾病的应用价值,对比不同疾病的FA、ADC值,总结诊断经验。方法选取2015-02—2016-02于我院神经内科接受常规MRI检查的中枢神经系统疾病患者34例,选择同期健康的同龄体检者34例为对照组,进行DTI检查。结果阿尔茨海默病组扣带束、扣带束后部、上纵束、顶叶白质FA值及扣带束后部、上纵束ADC值与对照组存比较差异均有统计学意义(P0.05);脑梗死、轻度创伤性脑损伤表现与阿尔茨海默病组相类似,与正常人群相比,脑梗死、轻度创伤性脑损伤患者部分脑白质区域FA显著下降,上纵束、内囊、额叶等均有分布,与受创、梗死部位等关系密切,部分白质纤维束MD值显著上升;通过脑白质FA、ADC诊断中枢神经系统疾病敏感性97.06%(33/34),特异度88.23%(30/34),阳性符合率92.65%(63/68),高于常规MRI诊断,差异有统计学意义(P0.05)。结论 DTI可弥补常规MRI不足,通过分析脑白质FA等指标变化,诊断中枢神经系统疾病。  相似文献   

3.
目的探讨额叶胶质瘤相关癫(FGRE)患者白质纤维束网络变化特点。方法前瞻性收集2014年1月至2017年12月共13例额叶胶质瘤相关癫患者和13例正常对照者,行MRI常规扫描和扩散张量成像(DTI),采用基于纤维束示踪的空间统计学方法(TBSS)观察全脑白质纤维束网络改变。结果与正常对照组相比,FGRE组患者全脑平均扩散率(MD)值显著升高,在3个区块13条白质纤维束中存在显著变化(FWE校正,均P 0.05);部分各向异性(FA)值变化区域与MD值大致相同,但是差异未达到统计学意义(FWE校正,P 0.05)。结论额叶胶质瘤相关癫的发生与肿瘤外区域特定白质纤维束网络改变相关。通过DTI参数和TBSS分析可初步揭示额叶胶质瘤相关癫患者早期白质纤维束网络的改变,尤其是MD值可以成为预测癫风险的影像学指标。  相似文献   

4.
目的探讨磁共振弥散张量成像在胶质瘤术前评估中的价值。方法对19例经病理证实胶质瘤的患者术前进行弥散张量成像,观察白质纤维束与肿瘤的关系,测量肿瘤实质区和周边水肿区的FA值。结果颅内胶质瘤所致白质纤维异常有三种基本改变:移位、浸润和破坏。19例中10例移位伴破坏,5例单纯浸润,4例浸润伴破坏;肿瘤的实质区和周边水肿区的FA值与对侧大脑白质FA值相比较存在显著差异(P〈0.05)。肿瘤的实质区和周边水肿区FA值之间无统计学显著差异(P〉0.05)。结论弥散张量成像技术可以显示胶质瘤与周围白质纤维束的关系,FA值不能区分肿瘤实质与周边水肿区。  相似文献   

5.
目的应用弥散张量成像(DTI)观察Broca失语症脑内相关白质纤维结构的改变。方法使用Siemens verio3.0T MR扫描机对10例Broca失语症患者和10例健康成人进行常规序列及DTI扫描,利用DTI studio软件进行后处理,计算Broca区、弓状束的FA值、DCavg值。结果 10例Broca失语症病变均位于左侧大脑半球。失语组左侧Broca区和弓状纤维束FA值和DCavg值较右侧及对照组左侧降低,差异有统计学意义(P0.05)。结果 Broca失语除语言功能区的损伤引起,其纤维通路的损伤亦可导致Broca失语的发生。  相似文献   

6.
目的应用扩散张量成像(DTI)研究阿尔茨海默病和遗忘型轻度认知损害患者白质和颞干纤维束部分各向异性(FA)值变化特点,探讨颞干纤维束损伤机制及其对阿尔茨海默病和遗忘型轻度认知损害的诊断与鉴别诊断价值。方法应用常规MRI和DTI测量阿尔茨海默病(10例)、遗忘型轻度认知损害(10例)和正常对照者(10例)颞干纤维束(包括前连合、钩束、额枕下束)及前额叶、颞叶、顶叶、枕叶白质FA值,比较各组受试者左右侧对称部位白质和颞干纤维束FA值变化。结果各组受试者左右侧对称部位白质和颞干纤维束FA值差异无统计学意义(均P0.05),但其前连合、钩束、额枕下束及前额叶白质FA值差异具有统计学意义(均P0.05)。其中,阿尔茨海默病组前连合、钩束、额枕下束FA值低于遗忘型轻度认知损害组(均P0.05),前连合、钩束、额枕下束及前额叶、顶叶白质FA值低于正常对照组(均P0.05);而遗忘型轻度认知损害组与正常对照组前连合、钩束、额枕下束及前额叶白质FA值差异无统计学意义(均P0.05)。结论阿尔茨海默病和遗忘型轻度认知损害患者与正常老年人颞干纤维束FA值存在显著差异,提示颞干纤维束在阿尔茨海默病患者白质损伤中具有重要意义,DTI检查有助于阿尔茨海默病与遗忘型轻度认知损害和正常老龄化的鉴别诊断。阿尔茨海默病前连合、钩束、额枕下束及前额叶、顶叶白质FA值异常具有良好的临床诊断价值。  相似文献   

7.
[目的]评价磁共振弥散张量成像(DTI)对功能区脑肿瘤手术的指导意义和应用价值.[方法]对25例患者行头部DTI检查,立体显示肿瘤与脑白质纤维束的关系,术前评估,设计手术入路,对所有病例行显微外科肿瘤切除手术治疗.[结果]本组脑肿瘤中累及脑白质纤维束区域主要位于锥体束和内囊,其中脑白质纤维束破坏13例,移位12例.肿瘤全切除11例,次全切除14例,无手术死亡.术前存在脑白质纤维束受累所致的神经功能阳性体征者术后改善13例,无变化者10例,加重2例.[结论]DTI能够清晰显示脑肿瘤对白质纤维束的累及关系,对神经外科优化手术设计、决定手术切除范围和评估术后神经功能具有指导意义.  相似文献   

8.
目的 探讨弥散张量成像(DTI)在脑深部肿瘤术前评估和手术设计中的作用.方法 回顾性分析20例脑深部肿瘤病人的临床资料,利用各向异性分数(FA)图和纤维示踪图(DTT),观察白质纤维束结构、走行及其与肿瘤的毗邻关系,测量病侧白质纤维束及其对应健侧白质纤维束的FA值、弥散系数(ADC)值.结果 白质纤维束单纯推移5例,单纯破坏7例,推移并破坏8例.单纯破坏、推移并破坏者.其病侧与健侧FA值、ADC值比较均有显著差异(P <0.05);而单纯推移者,其病侧与健侧队值、ADC值比较无显著差异(P >0.05).肿瘤全切除15例,次全切除3例,部分切除2例.12例随访6个月-2年,平均1年.正常工作、学习8例,生活自理但未参加工作3例,死亡1例.结论 DTI有助于准确判断肿瘤与周围白质纤维束的毗邻关系,对脑深部肿瘤术前评估和手术设计有重要指导意义.  相似文献   

9.
目的探讨磁共振弥散张量成像(DTI)部分各向异性指数(FA)值和表观弥散系数(ADC)值在胶质瘤与淋巴瘤鉴别方面的临床应用价值。方法收集术后经组织病理学证实低级别胶质瘤患者12例,高级别胶质瘤14例,淋巴瘤10例。影像资料:常规MRI平扫、磁共振成像液体衰减反转恢复序列(FLAIR)、增强扫描检查、DTI检查,工作站自动生成各向异性指数图(FA图)及表观弥散系数图(ADC图),获取瘤周水肿区及肿瘤实质区的FA值、ADC值,分析比较胶质瘤与淋巴瘤之间定量参数有无统计学差异,分析胶质瘤及淋巴瘤肿瘤实质及周围神经纤维的侵犯情况。结果低级别胶质瘤、高级别胶质瘤肿瘤实质区及瘤周水肿区DTI定量参数ADC值、FA值存在差异,尤其是瘤周水肿区;淋巴瘤的肿瘤实质区ADC值低于高级别胶质瘤肿瘤,瘤周水肿区DTI定量参数FA值存在差异。结论 DTI能准确反映瘤周白质纤维束受压移位、浸润与破坏改变,可为临床诊断与鉴别诊断提供更多依据。  相似文献   

10.
目的研究路易体痴呆(DLB)和帕金森病(PD)患者的脑白质纤维束的改变情况。方法对10例DLB患者(DLB组)、16例PD患者(PD组)及16例正常对照者(正常对照组)进行DTI扫描,采用基于纤维骨架的空间统计方法(TBSS)对三组全脑DTI的各向异性分数(FA)和平均弥散率(MD)两两比较,并分析FA值、MD值与临床数据的相关性。结果与正常对照组比较,DLB组左下纵束、左下额枕束、双侧上纵束FA值、MD值明显改变(P=0.002,P=0.012;P=0.013,P=0.015),而PD组仅胼胝体白质纤维束MD值明显改变(P=0.036)。与PD组比较,DLB组左下纵束、左下额枕束FA值、MD值明显改变(P=0.04;P=0.005)。DLB组左下纵束、左下额枕束FA值与病程呈负相关(r=-0.708,P0.05),与MMSE评分呈正相关(r=0.023,P0.05),左上纵束MD值与统一PD评定量表Ⅲ呈正相关(r=0.682,P0.05)。结论 DLB患者会出现明显的白质纤维束改变,尤其是左下纵束、左下额枕束的改变对DLB的早期诊断有着重要的参考价值。  相似文献   

11.
Vanishing white matter disease (VWM) is one of the most frequent inherited childhood white matter disorders. We present the brain and spinal cord disease progression on serial conventional magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) in a 4-year-old boy. Consecutive MRI examinations demonstrated a progression of the signal abnormalities in the cerebral white matter. Globally, apparent diffusion coefficient (ADC) values as well as axial and radial diffusivity increased over time, while fractional anisotropy (FA) values decreased. Involvement of the cervical posterior spinal tracts and mild global spinal cord atrophy was found. In conclusion, serial MRI and DTI studies may help to better understand the selective injury of the myelin and axons in VWM disease. These data may help in monitoring disease progression. Our data also show that complete neuroimaging work-up in VWM should also include the spinal cord.  相似文献   

12.
目的 应用磁共振弥散张量成像(DTI)研究腔隙性脑梗死(LI)患者脑"形似正常区"白质损害(WML)的特点及其与血清超敏C反应蛋白(hs-CRP)的相关性.方法 选取南方医科大学南方医院神经内科自2008年3月至10月收治人院的32例LI患者和10名年龄及文化程度相当的健康志愿者分别做为研究组和对照组;行脑部T1WI、T2WI、DWI、水抑制反转恢复序列(FLAIR)和DTI扫描,选择双侧额叶白质、前部扣带回、前部扣带、半卵圆中心、视放射、前角周围白质、后角周围白质、尾状核头部、丘脑、海马旁回、外囊以及胼胝体膝部、胼胝体干、肼胝体压部等25个T1WI、T2WI"形似正常区"作为兴趣区(ROI),分别测量部分各向异性值(FA)、平均弥散系数(ADC)值;应用免疫透射比浊法检测血清hs-CRP水平.结果 与对照组比较,研究组左、右侧额叶白质,肼胝体膝部,左、右侧前部扣带,左、右侧半卵圆中心.左、右侧视放射,左侧前角、后角周围白质.左、右侧海马旁回.右侧外囊的FA值降低;胼胝体干、胼胝体压部、左侧半卵圆中心、左侧后角周围白质、左侧海马旁回的ADC值升高,差异均有统计学意义(P<0,05).其中左、右侧额叶白质,胼胝体膝部的FA值与hs-CRP水平呈负相关关系(r=-0.642,P=0,021;r=0.388,P=0.016;r=-0.402,P=0.028).结论 LJ患者常规MRI上显示"形似正常区"的白质早期已存在广泛损害;部分受损白质区域FA值与hs-CRP水平呈负相关关系,提示动脉硬化可能在LI患者WML发病机制中超重要作用;DTI可作为早期发现WML、评估预后及治疗效果的一种重要工具.  相似文献   

13.
目的利用磁共振弥散张量成像(DTI)探讨脑梗死病人脑白质纤维束各向异性特征和白质纤维束受损与临床预后关系。方法对23例脑梗死患者行DTI检查,以三维立体弥散张量成像为基础的色彩图进行图像后处理,评价脑梗死区周边纤维束的情况,将纤维束分为受压移位、变细萎缩和破坏中断三类,并与临床预后、神经功能缺损程度比较。结果三维成像所见与病人预后关系密切。所有脑白质纤维束萎缩和中断的患者,在随访过程中存在不同程度脑功能损伤,而脑白质受压移位的病人神经功能完全或近乎完全恢复。结论在脑梗死中,DTI能直接观察到白质纤维束的变化,对于评估临床预后具有重要作用。  相似文献   

14.
目的 探讨弥散张量成像(diffusion tensor imaging,DTI)对颅内环形强化病变的诊断价值.方法 53例颅内单发环形强化病例术前行DTI扫描,分别测量病变坏死区、灶周水肿区及对侧正常脑实质的平均弥散系数(MD)值及各向异性分数(FA)值.并通过弥散张量纤维束成像(diffusiontensor tracking,DTT)观察病灶与白质纤维束的关系.结果 脑脓肿坏死区的MD值为(0.60±0.13)×10-3 mm2/s,FA值为0.18±0.03,高级别星形细胞瘤MD值为(2.76±0.26)×10-3mm2/s,FA值为0.07±0.02,脑转移瘤MD为(2.82±0.29)×10-3mm2/s,FA值为0.06±0.02,前者与后两者间差异有统计学意义(P<0.01).高级别星形细胞瘤水肿区的FA值(0.23±0.06)与脑转移瘤(0.17±0.06)和脑脓肿(0.15±0.03)两者水肿区FA值差异有统计学意义(P<0.01).DTT可以较准确地反映病灶与白质纤维束的关系,为手术治疗及评估预后提供依据.结论 坏死区MD值及FA值有助于脑脓肿与环形强化脑肿瘤的鉴别;水肿区FA值有助于脑星形细胞瘤与转移瘤、脑脓肿的鉴别;DTT能够为优化手术方案及评估预后提供一定帮助.  相似文献   

15.
AIMS: Abnormal cortical development will lead to abnormal axons in white matter. The purpose was to investigate (1) the microstructural changes in subcortical white matter adjacent to malformations of cortical development (MCD) and (2) the deep white matter tracts using diffusion tensor imaging (DTI). METHODS: Thirteen children with a variety of MCD were recruited. The fractional anisotropy (FA), trace, and eigenvalues (lambdamajor, lambdamedium, lambdaminor) of subcortical white matter of MCD were compared with contralateral normal side. The deep white matter tracts were graded based on the size, color hues and displacement of the tracts as visualized on color vector maps and tractography; grade 1 was normal tract size and color hue, grade 2 was reduced tract size but preserved color hue and grade 3 was loss of color hue or failure of tracking on tractography. RESULTS: The subcortical white matter adjacent to abnormal cortex demonstrated reduced FA (p < 0.05) and tendency to increase trace (p = 0.06). There was a significant elevation in lambdamedium and lambdaminor (p < 0.05), but no significant change in lambdamajor (p > 0.05). Twelve cases demonstrated alteration in white matter tracts. Seven cases of focal cortical dysplasia and two cases of transmantle MCD demonstrated grade 3 pattern of white matter tract. CONCLUSION: Reduced FA is a sensitive but nonspecific marker of alteration in microstructure of white matter. The elevated lambdamedium and lambdaminor may reflect a dominant effect of abnormal myelin. Alteration in white matter tracts was observed in most cases of MCD.  相似文献   

16.
目的:应用MR弥散张量成像(DTI)观察阿尔茨海默病(AD)患者脑白质纤维束完整性。方法:健康老年志愿者为对照组(NC)组、遗忘型轻度认知障碍(aMCI)组、AD组和皮质下缺血性血管性痴呆(SIVD)组各20例,行常规MRI和DTI扫描后,测定相同感兴趣区(ROI)的各向异性分数(FA)值和表观扩散系数(ADC)值进行比较。结果:与NC组比较, AD组前额叶、颞叶、海马等部位FA值降低,颞叶、海马等部位ADC值升高(P〈0.05);aMCI组仅扣带束FA值降低,与AD组比差异有统计学意义(P〈0.05);SIVD组下额枕束等部位FA值下降,ADC值升高,与AD组比较差异有统计学意义(P〈0.05)。结论:DTI可以用来评估白质纤维束完整性,AD组白质损害甚于aMCI患者;扣带束FA值可以作为aMCI患者筛查的指标;根据受累部位不同可对SIVD与AD进行鉴别。  相似文献   

17.
PURPOSE: Focal cortical dysplasia (FCD) is one of the most common underlying pathologic substrates in patients with medically intractable epilepsy. While magnetic resonance imaging (MRI) evidence of FCD is an important predictor of good surgical outcome, conventional MRI is not sensitive enough to detect all lesions. Previous reports of diffusion tensor imaging (DTI) abnormalities in FCD suggest the potential of DTI in the detection of FCD. The purpose of this study was to study subcortical white matter underlying small lesions of FCD using DTI. METHODS: Five patients with medically intractable epilepsy and FCD were investigated. Diffusion tensor imaging images were acquired (20 contiguous 3 mm thick axial slices) with maps of fractional anisotropy (FA), trace apparent diffusion coefficient (trace/3 ADC), and principal eigenvalues (ADC parallel and ADC perpendicular to white matter tracts) being calculated for each slice. Region of interest analysis was used to compare subcortical white matter ipsilateral and contralateral to the lesion. RESULTS: Three subjects with FCD associated with underlying white matter hyperintensities on T2 weighted MRI were observed to have increased trace/3 ADC, reduced fractional anisotropy and increased perpendicular water diffusivity which was greater than the relative increase in the parallel diffusivity. No DTI abnormalities were identified in two patients with FCD without white matter hyperintensities on conventional T2-weighted MRI. CONCLUSIONS: While DTI abnormalities in FCD with obvious white matter involvement are consistent with micro-structural degradation of the underlying subcortical white matter, DTI changes were not identified in FCD lesions with normal appearing white matter.  相似文献   

18.
The aging U.S. population and the recent rise in the prevalence of obesity are two phenomena of great importance to public health. In addition, research suggests that midlife body mass index (BMI) is a risk factor for dementia, a particularly costly disease, in later life. BMI could influence brain health by adversely impacting cerebral white matter. Recently, greater BMI has been associated with lower white matter fractional anisotropy (FA), an index of tissue microstructure, as measured by diffusion‐tensor imaging in midlife. The aim of this study was to investigate the role of abdominal obesity, the most metabolically active adipose tissue compartment, and white matter microstructure in midlife. Community dwelling participants (N = 168) between the ages of 40–62 underwent MRI scanning at 3T and a general health assessment. Inferences were made on whole brain white matter tracts using full‐tensor, high‐dimension normalization, and tract‐based spatial statistics. Higher waist circumference was associated with higher FA, indicating more directional diffusion in several white matter tracts controlling for age, sex, triglycerides, systolic blood pressure, fasting glucose, and HDL‐cholesterol. Post hoc analysis revealed that greater waist circumference was associated with lower axial diffusivity, indicating lower parallel diffusion; lower radial diffusivity, indicating lower perpendicular diffusion; and lower mean diffusivity, indicating restricted diffusion. This is the first study to report a positive relationship between obesity and FA, indicating a more complicated view of this relationship in the aging brain. Hum Brain Mapp 38:3337–3344, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   

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