fMRI在癫大脑网络中的研究进展

癫是神经元异常放电所致的慢性发作性神经功能障碍性疾病,因其发作的反复性、复杂性和多样性,大脑的结构和功能均受到严重损害。近年来,随着功能成像技术的不断发展,功能MR成像(f MRI)在癫中的应用越来越广泛,尤其是静息态f MRI(rs-f MRI)和同步联合脑电图f MRI(EEG-f MRI)的应用揭示了癫复杂网络、结构网络及功能网络改变的特点,为理解癫发病机制提供了重要的帮助。     

静息态功能MRI在针灸治疗药物成瘾研究中的应用及意义

在临床上针灸治疗药物成瘾疗效显著,但有关针灸治疗药物成瘾起效的机制尚不明确。静息态功能MRI技术可以客观地反映药物成瘾下脑活动的异常模式以及针灸对药物成瘾病人大脑功能区网络连接的影响,为针灸治疗药物成瘾的神经机制研究提供新的信息和思路。就静息脑态功能MRI在针灸治疗药物成瘾中的研究应用及意义作一综述。     

儿童癫痫静息态fMRI的研究进展

癫痫是脑神经元同步异常放电导致的脑功能紊乱综合征,其反复发作可造成认知功能的损伤和行为的异常。静息态功能MRI（rs-fMRI）是一种血氧水平依赖功能MRI,可对大脑静息态下的自发活动进行研究。目前大量癫痫rs-fMRI 的研究主要集中于成年病人,然而儿童癫痫的病因、发病机制及临床治疗等都与成人癫痫不尽相同。主要对近年来rs-fMRI 在儿童癫痫静息态网络、认知功能障碍研究及其在儿童癫痫手术治疗方面的应用予以综述。     

儿童癫静息态fMRI的研究进展

癲是脑神经元同步异常放电导致的脑功能紊乱综合征,其反复发作可造成认知功能的损伤和行为的异常。静息态功能MRI(rs-fMRI)是一种血氧水平依赖功能MRI,可对大脑静息态下的自发活动进行研究。目前大量癲rs-fMRI的研究主要集中于成年病人,然而儿童癫的病因、发病机制及临床治疗等都与成人癫不尽相同。主要对近年来rs-fMRI在儿童癫静息态网络、认知功能障碍研究及其在儿童癫手术治疗方面的应用予以综述。     

静息态脑功能网络分析方法及在肝性脑病的研究进展

静息态脑功能网络分析方法是目前脑功能研究最常用、最基本的方法之一。该方法利用血氧水平依赖功能磁共振成像(BOLD-f MRI)采集数据,分析全脑或特定脑区脑网络连接强弱的情况,不仅能无创定位功能网络连接异常的脑区,还能了解各种神经心理疾病的病理生理基础及发病机制。近年来,随着影像技术的发展、脑网络分析方法的不断完善,静息态脑功能网络的研究为临床疾病的诊断治疗提供了更为广阔的思路。     

昏迷患者静息态脑功能局部一致性fMRI研究

目的 探讨昏迷患者生物学特征可能的基线脑功能基础.方法 昏迷患者及正常人各12例,使用飞利浦3.0T磁共振系统对受试者进行全脑静息状态功能磁共振成像(fMRI)检查.用SPM5及北京师范大学认知神经科学与学习国家重点实验室自行研制开发的REST及DPARSF软件进行数据的处理和统计学分析,比较昏迷患者与正常人在静息状态下局部一致性的差异.结果 与正常人相比,昏迷患者组小脑、颞叶、额叶、顶下小叶、后扣带回及楔前叶的自发活动局部一致性减低 (P<0.01).结论 运用静息态脑功能成像可能为研究昏迷患者的病理生理状态提供新的方向;昏迷患者在静息状态下多个脑区ReHo值显著低于健康对照,提示昏迷神经生理机制并非单一脑区功能的异常改变,而是整个大脑功能网络的异常,是一种大脑功能失连接的表现.     

脊髓损伤后大脑网络连接变化的功能MRI研究进展

脊髓损伤(SCI)后大脑功能的重塑对患者的感觉运动恢复起着重要作用,但亦会导致病理性损害。到目前为止,其重塑和对功能影响的机制尚不清楚。静息态f MRI作为一种无创且能直观显示脑区活动的技术,已经成为评估大脑功能变化的重要手段,为SCI后脑网络及功能连接的机制研究提供了有效的方法。本文针对SCI后静息态脑功能连接(FC)的变化及其可能机制进行综述。     

脑网络功能连接预测抑郁症重复经颅磁刺激疗效的研究进展

抑郁症是一种情感障碍性疾病。重复经颅磁刺激(rTMS)是治疗抑郁症的一种非侵入性神经刺激技术。静息态功能磁共振成像(rs-fMRI)主要是研究大脑在静息状态时的自发活动;功能连接在分析抑郁症rTMS时较为常用,反映了静息状态下不同脑区血氧信号的即时联系,表明不同脑区间连接上的功能差异。本研究对近年脑网络功能连接预测rTMS治疗抑郁症疗效的相关文献进行综述,有望为抑郁症rTMS个性化治疗提供思路。     

癫痫的fMRI研究进展

癫痫为临床常见病、多发病,是大脑神经元过度或同步活动异常引起脑功能障碍的慢性神经系统疾病,危害极大.MRI是癫痫的常用影像检查方法,但部分患者MRI常规序列可表现为阴性.fMRI对癫痫的诊断、难治性癫痫的定位定侧、术前评估及癫痫的病理生理机制研究具有重要价值.就癫痫的动脉自旋标记(ASL)灌注成像、静息态fMRI及MR...     

静息态脑功能成像在青少年网络成瘾中的初步研究

目的运用静息态脑功能磁共振成像局部一致性(ReHo)方法探索网络成瘾(internet addiction,IA)青少年静息态脑功能的变化。资料与方法采用3.0TMRI对18名IA青少年和18名年龄、性别相匹配的正常对照组进行静息态脑功能扫描。采用静息态功能磁共振数据处理工具包(DPARSF)进行数据预处理和ReHo分析,采用双样本t检验分析,P<0.001,体素个数>10个被认为有统计学意义。结果在静息状态下,与正常组比较,IA组以下脑区ReHo降低有统计意义,包括右侧海马旁回、右侧舌回、左侧脑岛、右侧中央后回和左侧顶下小叶。结论 IA青少年静息状态下脑默认网络与正常对照组存在差异,这可能为研究IA的发病机制提供新的依据。     

静息态磁共振成像技术对终末期肾病患者异常脑功能连接的研究进展

终末期肾病(ESRD)可由于多种复杂的因素对患者的大脑功能产生影响,其具体表现为脑功能网络连通性的普遍降低,以及部分功能网络之间连通活动的减弱。异常的脑功能连接是终末期肾病患者认知功能障碍产生的重要原因。静息态磁共振功能成像(rs-fMRI)可以通过监测局部血氧水平的改变来反映大脑的神经活动,从而间接反映脑网络功能的整合情况,它是探究肾病患者异常脑功能连接生理机制的重要手段。本文就脑功能连接的理论基础及静息态磁共振成像对ESRD患者脑功能连通性的应用进展进行综述。     

Molecular neuroimaging: from conventional to emerging techniques

The use of molecular imaging techniques in the central nervous system (CNS) has a rich history. Most of the important developments in imaging-such as computed tomography, magnetic resonance imaging, single photon emission computed tomography, and positron emission tomography-began with neuropsychiatric applications. These techniques and modalities were then found to be useful for imaging other organs involved with various disease processes. Molecular imaging of the CNS has enabled scientists and researchers to understand better the basic biology of brain function and the way in which various disease processes affect the brain. Unlike other organs, the brain is not easily accessible, and it has a highly selective barrier at the endothelial cell level known as the blood-brain barrier. Furthermore, the brain is the most complex cellular network known to exist. Various neurotransmitters act in either an excitatory or an inhibitory fashion on adjacent neurons through a multitude of mechanisms. The various neuronal systems and the myriad of neurotransmitter systems become altered in many diseases. Some of the most devastating diseases, including Alzheimer disease, Parkinson disease, brain tumors, psychiatric disease, and numerous degenerative neurologic diseases, affect only the brain. Molecular neuroimaging will be critical to the future understanding and treatment of these diseases. Molecular neuroimaging of the brain shows tremendous promise for clinical application. In this article, the current state and clinical applications of molecular neuroimaging will be reviewed.     

Neuropsychiatric disorders: Investigation of schizophrenia and substance abuse

Because neuropsychiatric disorders involve functional and neurochemical cerebral abnormalities, positron emission tomography (PET) is ideally suited for their investigation. The use of tracers to measure regional brain glucose metabolism and/or blood flow has allowed the evaluation of brain function in psychiatric patients. The use of radioligands to assess receptor concentration has enabled an evaluation of the extent to which specific neurotransmitter systems are involved in the pathogenesis of mental illness. This article reviews the application of PET technology to the understanding of schizophrenic disorders and substance abuse.     

PET受体显像在肥胖人群神经功能改变成像中的作用

全球肥胖发病率正在不断攀升,肥胖导致的各种相关疾病的发生风险也显著升高。虽然肥胖人群的大脑结构和脑区兴奋模式变化已通过一些MRI和功能MRI研究揭示,但其神经功能在分子水平上的改变尚不完全清楚。PET受体显像能够在体评估神经受体功能变化,目前已开始用于肥胖相关的神经功能研究。笔者主要综述PET受体显像在肥胖人群神经功能成像中的作用。     

Diffusion tensor imaging in normal aging and neuropsychiatric disorders

The application of diffusion imaging to the quantitative study of the effects of normal aging and neuropsychiatric diseases on brain tissue microstructure has witnessed its greatest development just over the last few years. Measures derived from diffusion imaging have already been shown to have great utility in identifying age- and disease-related degradation of regional microstructure, particularly of white matter. Investigations comparing diagnoses hold promise for contribution to differential diagnosis. Correlations with cognitive and motor performance provide evidence for functional ramifications of these diffusion measures.     

Clinical applications of functional magnetic resonance imaging

Despite its immediate success as a tool for basic research, the clinical application of functional MRI(fMRI) is still limited. FMRI has proven useful for presurgical functional mapping of the eloquent cortices. Localization of the sensorimotor cortex by fMRI may be of relatively limited value because the sensorimotor cortex can often be readily localized by means of anatomical methods. In contrast, the language cortices may not be localized anatomically and the language dominant hemisphere has been determined by invasive Wada test. Previous reports have shown that fMRI can be a promising alternative to the Wada test. A recent clinical trial has suggested that fMRI can be used to diagnose Alzheimer's disease in its earliest stage, detecting subclinical deterioration of the memory function. FMRI may be useful to predict the future decline of memory in people with genetic risks. Monitoring of the functional recovery of post-stroke brains may be another promising clinical application of fMRI. FMRI has demonstrated functional reorganization of the brain that may be related to the restoration of motor and language functions.     

Increasing benefit of magnetic resonance imaging in multiple sclerosis

Magnetic resonance imaging (MRI) has emerged as an essential tool of multiple sclerosis (MS) diagnosis and has opened up completely new prospects in MS research and treatment trials. It is a sensitive method that gives direct evidence of tissue pathology and has greatly increased our knowledge of MS. In clinical work, MRI is used to confirm and exclude the diagnosis of MS. The international recommendation is that every suspected MS patient should undergo at least one brain MRI. T2-weighted images are the standard tool in clinical work, and functional imaging methods are mainly used in MS research. The subtypes and the course of the disease cause variation in MRI findings. Here, we present a general overview of MR findings in MS.     

SPECT/CT骨显像在足踝关节病诊治中的应用进展

足踝关节复杂的解剖结构给检查带来了较大的困难。目前足踝关节病的初步检查方法是行X线评估,MRI检查则用于进一步明确诊断。99Tcm-MDP平面骨显像对骨代谢的病变具有很高的灵敏度,但由于分辨率低和缺乏解剖结构信息,因而对足踝关节的检查缺乏特异性。99Tcm-MDP SPECT/CT断层骨显像将骨显像的高灵敏度与CT提供的精细解剖结构完美结合,从而更好地显示99Tcm-MDP摄取的位置和解剖结构的改变。近年来SPECT/CT断层骨显像已逐步用于足踝关节病变的辅助诊断。笔者对SPECT/CT断层骨显像在足踝关节病变诊断中的临床应用进行了综述。