多模态MRI在阿尔茨海默病早期诊断中的研究进展

阿尔茨海默病(Alzheimer's disease,AD)是发生于中老年人中最常见的中枢神经系统退行性疾病,以进行性认知障碍和行为非认知功能能力的减低为主要症状。近年来,随着磁共振成像(magnetic resonance imaging,MRI)多种序列的逐渐成熟,多模态MRI诊断在AD早期诊断中占有越来越重要的角色;作者就磁共振成像中结构性磁共振(structural magnetic resonance imaging,s MRI)、磁共振波谱成像(magnetic resonance spectroscopy,MRS)、磁共振弥散张量成像(diffusion tensor imaging,DTI)和磁共振扩散峰度成像(diffusion kurtosis imaging,DKI)、磁敏感加权成像(susceptibility weighted imaging,SWI)和定量磁敏感成像(quantitative susceptibility mapping,QSM)及静息态功能磁共振(functional MRI,f MRI)在AD早期诊断中的应用进行综述。     

低频振幅成像技术在眼科疾病的应用进展

低频振幅(amplitude of low frequency fluctuation,ALFF)是一种静息态的功能磁共振成像(resting-state functional magnetic resonance imaging,rs-fMRI)技术,用于测量神经活动中血氧水平依赖性功能磁共振成像(blood oxygenation level dependent functional MRI,BOLD-fMRI)信号强度的自发波动,该信号反映了静息时局部自发性脑活动的强度。基于ALFF算法的rs-fMRI在眼部多种疾病的研究中得到了越来越广泛的应用,它为研究眼部疾病特征与局部脑功能区变化间的联系开辟了一条全新的认识思路。作者就ALFF技术在眼科疾病中的应用进展综述如下。     

《磁共振成像》杂志可以直接使用的医学缩略语有哪些

对于磁共振成像专业领域为大家熟知的部分专业名词缩略语可以直接使用。本刊可以直接使用的医学缩略语如下(按照英文首字母顺序排列):ADC (apparent diffusion coefficient):表观扩散系数;AUC (area under the curve):曲线下面积;fMRI (functional magnetic resonance imaging):功能磁共振成像;MRI (magnetic resonance imaging):磁共振成像;MRS (magnetic resonancespectroscopy):磁共振波谱;ROC曲线(receiver operating characteristic curve):受试者操作特征曲线;ROI (region of interest):感兴趣区。     

本刊可以直接使用的医学缩略语有哪些

对于磁共振成像专业领域为大家熟知的部分专业名词缩略语可以直接使用。本刊可以直接使用的医学缩略语如下(按照英文首字母顺序排列):ADC(apparent diffusion coefficient):表观扩散系数;AUC(area under the curve):曲线下面积;fMRI(functional magnetic resonance imaging):功能磁共振成像;MRI(magnetic resonance imaging):磁共振成像;MRS(magnetic resonancespectroscopy):磁共振波谱;ROC曲线(receiver operating characteristic curve):受试者操作特征曲线;ROI(region of interest):感兴趣区。     

本刊可以直接使用的医学缩略语有哪些

正对于磁共振成像专业领域为大家熟知的部分专业名词缩略语可以直接使用。本刊可以直接使用的医学缩略语如下(按照英文首字母顺序排列):ADC (apparent diffusion coefficient):表观扩散系数;AUC (area under the curve):曲线下面积;f MRI (functional magnetic resonance imaging):功能磁共振成像;MRI (magnetic resonance imaging):磁共振成像;MRS (magnetic resonancespectroscopy):磁共振波谱;ROC曲线(receiver operating characteristic curve):受试者     

fMRI和DTI在功能区胶质瘤手术中的应用价值

目的:分析功能磁共振成像(functional magnetic resonance imaging,fMRI)和弥散张量成像(diffusion tensor imaging,DTI)在功能区胶质瘤手术中的指导价值.方法:收集2018年1月—2019年1月于深圳市龙华区人民医院接受手术治疗的50例功能区胶质瘤患者的临...     

《磁共振成像》杂志可以直接使用的医学缩略语有哪些

正对于磁共振成像专业领域为大家熟知的部分专业名词缩略语可以直接使用。本刊可以直接使用的医学缩略语如下(按照英文首字母顺序排列):ADC (apparent diffusion coefficient):表观扩散系数;AUC (area under the curve):曲线下面积;fMRI (functional magnetic resonance imaging):功能磁共振成像;MRI (magnetic resonance imaging):磁共     

本刊可以直接使用的英文缩略语北大核心CSCD

计算机体层摄影术(computed tomography,CT)多层螺旋CT(multiple-slice CT,MSCT)多排螺旋CT(multi-detector CT,MDCT)高分辨率CT(high resolution CT,HRCT)容积CT(volumetric computed tomography,VCT)CT血管造影(computed tomographic angiography,CTA)CT静脉造影(CT venography,CTV)磁共振成像(magnetic resonance imaging,MRI)功能磁共振成像(functional magnetic resonance imaging,fMRI)扩散(弥散)加权成像(diffusion weighted imaging,DWI)磁敏感加权成像(susceptibility-weighted imaging,SWI)     

基于MRI的HIV相关神经认知功能障碍综合征研究现状与进展

人类免疫缺陷病毒(human immunodeficiency virus,HIV),即艾滋病(acquired immune deficiency syndrome,AIDS)病毒,是造成人类免疫系统缺陷的一种病毒。联合抗逆转录病毒治疗(combination antiretroviral therapy,cART)已将HIV从快速致命的疾病转变为更易处理的慢性疾病。因此,接受cART的HIV感染者(HIV+)个体的寿命几乎与HIV未感染(HIV-)个体一样长。感染之后HIV进入到大脑并且一段时间之后可以导致HIV相关的神经认知疾病(HIV associated neurocognitive disorders,HAND)。磁共振成像(magnetic resonance imaging,MRI)技术[包括磁共振波谱(magnetic resonance spectroscopy,MRS)、结构MRI、扩散张量成像(diffusion imaging,DTI)和功能磁共振成像(functional magnetic resonance imaging,fMRI)]和正电子发射断层扫描(positron emission tomography,PET)已被用于HIV+个体。作者将详细介绍各种磁共振成像技术以及脑网络在HAND方面的应用和研究进展。     

功能性磁共振成像技术及其对腮腺肿瘤的应用价值

<正>功能性磁共振成像(functional magnetic resonance imaging,f MRI),目前作为常规MR成像的有效辅助手段应用越来越多[1-6]。普遍认为,属于f MRI的技术主要包括磁共振波谱成像(MR spectroscopy,MRS)、动态增强磁共振成像(dynamic contrast-enhanced MRI,DCE-MRI)     

维吾尔语和汉语动词产生相关脑区的功能性磁共振成像研究

目的通过功能性磁共振成像（fMRI）观察母语为维吾尔语（简称维语）和汉语正常人执行动词产生任务时的脑激活区及其脑激活差异区,探讨语言理解和产生的神经机制,以及脑损伤后语言障碍及其康复机制。 方法以维语和汉语名词为基本实验材料,通过血氧水平依赖功能性磁共振成像（BOLD-fMRI）扫描31例维吾尔族（语组）和28例汉族（汉语组）正常志愿者执行动词产生任务时的脑激活区,采集fMRI数据,并进行组内及组间比较。 结果汉语组的主要脑激活区为左侧尾状核、左侧枕下回、左侧梭状回、双侧辅助运动区（BA8/6区）、左侧BA32区、左侧楔前叶、左侧顶上、下小叶（BA7区）、左侧角回、右侧中央前回（BA9区）、左侧三角部额下回、右侧岛盖部额下回和双侧小脑。维语组的主要脑激活区为左侧中央前回（BA9区）、左侧岛盖部额下回、左侧三角部额下回和左侧小脑。维语组和汉语组组间比较发现,汉语组在左侧尾状核体、左侧眶部额中回、右侧尾状核头和双侧扣带回前部（BA32区）有明显激活,与维语组比较,差异有统计学意义（P<0.05）;而维语组未见比汉语组更明显激活的脑区。 结论维语和汉语正常人动词产生激活脑区不完全相同;维语文字的加工处理主要集中在左侧大脑半球;汉字加工处理比维语文字加工处理需要更多右侧大脑半球的参与。     

共同性斜视患者立体视觉相关皮层的BOLD-fMRI表现

目的观察共同性斜视患者立体视觉相关皮层的全脑BOLD-fMRI的表现。方法选取共同性斜视患者12例(共同性斜视组)和立体视觉正常者10名(正常组),接受BLOD-fMRI。采用SPM5软件包对数据进行预处理及分析。结果在立体图形刺激下,共同性斜视组可见右侧舌回和左侧枕中回激活,正常组可见双侧枕中回、双侧中央后回、右侧顶下小叶、左侧颞中回激活。共同性斜视组激活强度低于正常组(P<0.05),主要位于左侧枕中回、右侧枕下回、双侧缘上回、双侧颞下回、双侧额下回、左侧岛叶。结论在立体图形刺激下,共同性斜视患者脑区激活范围小于正常者,其立体视觉异常的中枢神经机制可能与顶叶、颞叶功能下降有关。     

语义、语法任务相关的脑功能磁共振成像

目的 设计适用于临床的脑语言fMRI任务刺激模式,并观察与汉语语言相关的脑功能区.方法 对22名健康志愿者在模拟临床语言生成模式下进行汉语语义、语法句子正确性判断,同时采集[MR]数据,通过后处理分析获得汉语语言相关的脑功能区,对其进行定位,并判断汉语的语言优势半球.结果 语义、语法判断任务激活的脑功能区有很大重叠,双侧额下回、双侧顶上小叶、双侧枕叶及左侧辅助运动区在两种语言任务中均有明显激活.汉语语言的脑激活区额下回表现为左侧半球优势.结论 应用语义、语法句子判断的语言刺激模式能激活正常人语言相关的脑功能区,简单易行,依从性好,激活脑功能区稳定,适用于临床对语言脑功能区进行定位.     

Neural correlates of continuous causal word generation

Causality provides a natural structure for organizing our experience and language. Causal reasoning during speech production is a distinct aspect of verbal communication, whose related brain processes are yet unknown. The aim of the current study was to investigate the neural mechanisms underlying the continuous generation of cause-and-effect coherences during overt word production. During fMRI data acquisition participants performed three verbal fluency tasks on identical cue words: A novel causal verbal fluency task (CVF), requiring the production of multiple reasons to a given cue word (e.g. reasons for heat are fire, sun etc.), a semantic (free association, FA, e.g. associations with heat are sweat, shower etc.) and a phonological control task (phonological verbal fluency, PVF, e.g. rhymes with heat are meat, wheat etc.). We found that, in contrast to PVF, both CVF and FA activated a left lateralized network encompassing inferior frontal, inferior parietal and angular regions, with further bilateral activation in middle and inferior as well as superior temporal gyri and the cerebellum. For CVF contrasted against FA, we found greater bold responses only in the left middle frontal cortex. Large overlaps in the neural activations during free association and causal verbal fluency indicate that the access to causal relationships between verbal concepts is at least partly based on the semantic neural network. The selective activation in the left middle frontal cortex for causal verbal fluency suggests that distinct neural processes related to cause-and-effect-relations are associated with the recruitment of middle frontal brain areas.     

The Effect of Task Relevance on the Cortical Response to Changes in Visual and Auditory Stimuli: An Event-Related fMRI Study

Attention is, in part, a mechanism for identifying features of the sensory environment of potential relevance to behavior. The network of brain areas sensitive to the behavioral relevance of multimodal sensory events has not been fully characterized. We used event-related fMRI to identify brain regions responsive to changes in both visual and auditory stimuli when those changes were either behaviorally relevant or behaviorally irrelevant. A widespread network of "context-dependent" activations responded to both task-irrelevant and task-relevant events but responded more strongly to task-relevant events. The most extensive activations in this network were located in right and left temporoparietal junction (TPJ), with smaller activations in left precuneus, left anterior insula, left anterior cingulate cortex, and right thalamus. Another network of "context-independent" activations responded similarly to all events, regardless of task relevance. This network featured a large activation encompassing left supplementary and cingulate motor areas (SMA/CMA) as well as right IFG, right/left precuneus, and right anterior insula, with smaller activations in right/left inferior temporal gyrus and left posterior cingulate cortex. Distinct context-dependent and context-independent subregions of activation were also found within the left and right TPJ, left anterior insula, and left SMA/CMA. In the right TPJ, a subregion in the supramarginal gyrus showed sensitivity to the behavioral context (i.e., relevance) of stimulus changes, while two subregions in the superior temporal gyrus did not. The results indicate a role for the TPJ in detecting behaviorally relevant events in the sensory environment. The TPJ may serve to identify salient events in the sensory environment both within and independent of the current behavioral context.     

Self, mother and abstract other: an fMRI study of reflective social processing

Using fMRI, we studied the neural correlates of self-referential processing by comparing BOLD signal changes during self and mother conditions of a self-reference effect (SRE) task. Conjunction analysis of these two conditions showed several common areas of significant activation, including the medial aspects of the superior frontal gyri, left inferior frontal gyrus, bilateral temporal poles, left superior temporal sulcus and left precuneus. The locations of the 7 strongest peak activations for the self condition and for the mother condition were compared on a subject-by-subject basis in native space. Of the 119 pairs of peaks explored, 87% were located within 2 voxels of each other, demonstrating the commonality of the brain regions subserving both self- and mother-referential processing within an individual subject. In group analyses of the self-referential vs. mother-referential contrast, small differences in activation strength were observed in the left superior frontal sulcus, right cingulate gyrus and the left fusiform gyrus. Greater activation for mother than for self was observed in bilateral temporal lobes. Subjects also performed a social attribution task (SAT) in which they inferred mental states about interacting geometric shapes. Activations from this visual theory of mind task were compared with the activations demonstrated during self-referential processing. Striking similarities were found, including overlapping activations in bilateral medial prefrontal cortices, left inferior frontal gyrus and precuneus. These data suggest that reflective analysis of self, mother and abstract others relies predominantly on the same neural architecture.     

汉语及图片语义加工机制的fMRI研究

目的利用功能磁共振成像(fMRI)技术探讨汉字及图片语义加工的脑机制。方法对13名正常青年受试者进行视觉方式呈现汉字及图片语义辨别任务的fMRI扫描,采用AFNI软件进行数据分析和脑功能区活动图像。结果fMRI显示两种任务均激活了左侧顶下小叶、额中回、额下回、右侧小脑及双侧梭状回、舌回、枕中回、枕下回、辅助运动区。其中左侧顶下小叶、额中回及双侧枕中回、梭状回在图片语义辨别任务激活明显强于汉字任务,有显著性差异(P<0.05)。结论汉字及图片语义的脑加工均存在偏侧化现象,图片语义的脑处理有更多的脑活动参与完成。     

脑卒中后运动性失语的功能磁共振成像研究

目的：探讨脑卒中后运动性失语症患者的语言功能恢复机制。方法：应用3T MR扫描仪对6例脑卒中患者失语后及康复后分别进行两次图片命名任务的BOLD fMRI扫描。实验采用组块设计方案,利用SPM5软件的总体线性模型（General linear model, GLM）进行后处理产生激活脑区图像。并对所有患者在发病后与康复后的脑内激活分布、大小、强度进行分析与比较。结果：所有患者在失语后左侧大脑半球语言相关脑区激活部分出现激活,其中3例右侧Broca’s镜像区出现激活。而在康复后所有患者的左侧大脑半球语言相关脑区激活增多,激活强度增加,其中左侧Broca’s区均出现激活,右侧Broca’s镜像区激活减弱。结论：失语后优势半球丧失功能的语言区移至对侧镜像区和优势半球未受累语言区的功能重组这两种机制都参与了语言功能恢复的过程,近期以右侧半球为主,远期左侧半球发挥更重要作用。     

Temporal and topographical characterization of language cortices using intraoperative optical intrinsic signals

We used intraoperative optical imaging of intrinsic signals (iOIS) and electrocortical stimulation mapping (ESM) to compare functionally active brain regions in 10 awake patients undergoing neurosurgical resection. Patients performed two to four tasks, including visual and auditory naming, word discrimination, and/or orofacial movements. All iOIS maps included areas identified by ESM mapping. However, iOIS also revealed topographical specificity dependent on language task. In Broca's area, naming paradigms activated both anterior and posterior inferior frontal gyrus (IFG), while the word discrimination paradigm activated only posterior IFG. In Wernicke's area, object naming produced activations localizing over the inferior and anterior/posterior regions, while the word discrimination task activated superior and anterior cortices. These results may suggest more posterior phonological activation and more anterior semantic activations in Broca's area, and more anterior/superior phonological activation and more posterior/inferior semantic activations in Wernicke's area. Although similar response onset was observed in Broca's and Wernicke's areas, temporal differences were revealed during block paradigm (20-s) activations. In Broca's area, block paradigms yielded a boxcar temporal activation profile (in all tasks) that resembled response profiles observed in motor cortex (with orofacial movements). In contrast, activations in Wernicke's area responded with a more dynamic profile (including early and late peaks) which varied with paradigm performance. Wernicke's area profiles were very similar to response profiles observed in sensory and visual cortex. The differing temporal patterns may therefore reflect unique processing performed by receptive (Wernicke's) and productive (Broca's) language centers. This study is consistent with task-specific semantic and phonologic regions within Broca's and Wernicke's areas and also is the first report of response profile differences dependent on cortical region and language task.