慢性神经系统疾病脑铁过度沉积的MR研究进展

在帕金森病(PD)、阿尔茨海默病(AD)、多发性硬化(MS)等一些慢性神经系统疾病患者脑内有过多铁沉积,导致自由基的产生,进而脂质过氧化,直接或间接影响着疾病的发生和发展.应用一些定量检测脑铁MR新技术,如磁敏感加权成像(SWI),可以敏感地检测到脑内铁浓度的变化.本文着重就检测脑铁的MR技术及PD、AD、MS患者脑铁异常沉积的MR表现进行综述.     

非侵入性脑刺激治疗脑卒中后偏侧忽略的临床研究进展

近年来,非侵入性脑刺激(Noninvasive Brain Stimulation,NBS)作为一种神经调控方法在国内外神经康复领域受到广泛关注。其中最主要的两项技术为经颅磁刺激(transcranial magnetic stimulation,TMS)和经颅直流电刺激(transcranial direct current stimulation,tDCS)。基于神经可塑性原理,非侵入性脑刺激可通过诱导突触形成、重组等途径改变神经通路,调节中枢神经功能。     

成对关联刺激影响脑卒中后运动功能的研究进展

脑卒中患者常留有不同程度的功能障碍,其中运动功能障碍会严重影响患者的生活质量。近年来,经颅电刺激和经颅磁刺激(TMS)等非侵入性脑刺激技术(NIBS)发展迅速,通过电/磁刺激调节皮质兴奋性来改善神经功能,但脑卒中患者运动功能的恢复程度仍难以达到理想水平。成对关联刺激(PAS)结合了TMS和周围神经电刺激的双重刺激模式,...     

1Hz重复经颅磁刺激对缺血性脑卒中后上肢运动功能的疗效

目的观察1 Hz重复经颅磁刺激(r TMS)对缺血性脑卒中后偏瘫上肢运动功能康复的效果。方法 40例缺血性脑卒中后上肢偏瘫患者被随机分配到治疗组(n=20)和对照组(n=20)。两组均给予常规康复治疗,治疗组采用r TMS刺激健侧皮层M1区,对照组给予假刺激。治疗后采用运动诱发电位(MEPs)、Fugl-Meyer上肢运动功能评分(FMA)和握力进行评定。结果治疗后,治疗组患侧MEPs振幅显著升高(P0.001)。治疗组握力和FMA评分显著优于对照组(P0.001),并至少可持续到治疗结束后1个月。所有患者均能耐受10次治疗,无严重不良反应发生。结论 r TMS刺激健侧皮层M1区可改善缺血性脑卒中后偏瘫上肢的运动功能。     

经颅磁刺激鉴别阿尔茨海默病和额颞叶痴呆

正阿尔茨海默病(AD)和额颞叶痴呆(FTD)是60岁以上老年人中最常见的神经退行性痴呆。AD的神经病理学特征是淀粉样蛋白沉积,而FTD的神经病理学特征是TDP-43蛋白和tau蛋白包涵体。鉴于经颅磁刺激(TMS)已被证实能评估中枢神经系统中不同的皮质回路,本研究旨在使用TMS评估神经生理参数以区分ADD与FTD。受试者为80例可疑AD患者,64例可疑FTD患者。由罗马的布雷西亚大学圣卢西亚基金会无创脑刺激组进行神经生理学评估。使用TMS 8字线圈,静息运动阈值在左侧运动皮质     

基于MR图像的苍白球内侧部帕金森手术靶点坐标定位

外科治疗是帕金森病(Parkinson's disease,PD)治疗中必不可少的一部分,尤其对服药5~8年出现药物时效降低或药物所致异动症的患者更是如此,目前以苍白球内侧部(globus pallidus internus,GPi)为手术靶点的脑损毁术及深部脑刺激术(deep brain stimulation,DBS)是治疗PD常用的有效方法。GPi的精确定位是实施上述手术的关键,对术后疗效的好坏有着极大的影响。为了实现对靶点目标的精准定位,GPi经历了由间接定位的Atlas-based方法到直接定位的MR imaging-based方法的发展与改变。其中MRI技术在GPi定位方法发展中起着举足轻重的作用,可以说没有MRI技术的飞速发展,也就不会有基于高分辨率MR图像的GPi直接定位方法出现。因此作者不仅对近20年GPi的手术坐标位置进行了回顾性总结,试图确定具一般适用意义的GPi坐标,而且介绍了MRI技术在GPi靶点定位手术中的应用及发展。     

多奈哌齐联合重复经颅磁刺激对老年性痴呆患者认知功能和尿AD7c-NTP水平的影响

目的观察多奈哌齐联合重复经颅磁刺激(r TMS)对老年性痴呆(AD)患者认知功能和尿AD7c-NTP水平的影响。方法采用信封法将70例AD患者分为对照组和观察组各35例,对照组予多奈哌齐口服治疗,观察组予多奈哌齐联合r TMS治疗,两组均持续治疗12周;分别于治疗前后行阿尔茨海默病病理行为评定量表(BEHAV-AD)、AD评估量表认知量表(ADAS-cog)、简易精神状态检查表(MMSE)、蒙特利尔认知功能测量表(MoCA)、改良Barthel指数量表(MBI)等量表评分,血清S100B、脂联素(ANP)、晨尿神经丝蛋白(AD7c-NTP)等生化指标水平测定,观察两组治疗过程中不良反应发生情况。结果治疗后,观察组BEHAV-AD、ADAS-cog评分及血清S100B、晨尿AD7c-NTP水平低于对照组,MMSE、MoCA、MBI评分及ANP水平高于对照组(P 0. 05)。结论多奈哌齐联合r TMS治疗可有效改善AD患者认知功能,其可能是通过调节S100B、ANP、AD7c-NTP水平而实现的。     

基于磁共振脑功能和脑结构成像的TMS线圈定位方法

经颅磁刺激(TMS)已广泛应用于临床治疗,TMS线圈准确地定位于相应的脑功能区,是TMS疗效以及对TMS疗效评估的关键。近年来,随着神经导航系统与TMS的结合,极大提高了TMS线圈定位的准确性,但这种多设备的组合有些环境下无法使用,如磁共振扫描时就无法使用导航。由于导航系统价格昂贵,在实际应用中许多TMS并没有整合导航系统,则TMS线圈的定位就成为一个棘手的问题。作者在MRI的基础上提出了一种TMS线圈定位方法。以重复经颅磁刺激(repetitive TMS,rTMS)治疗失语为例,1例脑卒中后失语患者,采集其高分辨率T1结构像以及言语任务功能MRI图像。使用SPM8软件进行数据处理,得到言语任务相应激活脑区,再用MRIcron软件加入T1结构像和脑激活图,从而构建大脑3D激活图,并在其上确定rTMS刺激部位,标记该部位在MRIcron中坐标,另外在头皮标记一个参照点并记下坐标。根据标记点及其坐标则可确定rTMS刺激部位在头皮的对应点。该方法确定TMS刺激点的整个过程都是在个体自身结构图上进行,具有较高的准确性,操作简单,便于实现,节约成本,可以灵活运用。     

MR模拟定位技术用于肿瘤放射治疗进展

放射治疗(放疗)是治疗肿瘤的主要方式之一。随着精准医疗的开展，临床对于放疗效率和精度的要求逐渐提高，制定和实施放疗计划过程中均需要更精准的解剖和功能图像，以定位病灶及周围组织结构。本文就MR模拟定位技术用于肿瘤放疗进展进行综述。     

高压氧联合重复经颅磁刺激对脑小血管病伴抑郁患者躯体症状及认知功能的疗效研究

目的:探讨高压氧联合重复经颅磁刺激(r TMS)对脑小血管病伴抑郁状态患者躯体症状及认知功能的临床疗效。方法:选取确诊150例脑小血管病伴抑郁状态患者,将其随机分为综合治疗组、r TMS组及高压氧组各50例;3组患者均给予常规内科处理(包括合并高血压、糖尿病、高血脂者予对症治疗),高压氧组在此基础上辅以高压氧治疗,r TMS组则辅以r TMS治疗,综合治疗组则辅以高压氧及r TMS治疗。于治疗前、治疗4周后分别采用汉密尔顿抑郁量表(HAMD)、蒙特利尔认知评估量表(Mo CA)及听觉Oddball刺激序列P300检测对各组患者躯体症状和认知功能进行评定。结果:治疗前各组患者HAMD、Mo CA、听觉Oddball刺激序列P300检测结果评分组间差异均无显著性意义(P0.05);经4周治疗后,发现各组患者上述指标均较治疗前明显改善(P0.05);且以综合治疗组的改善幅度尤为显著,r TMS组次之,各指标组间差异均具有显著性意义(P0.05)。结论:高压氧联合r TMS能显著改善脑小血管病伴抑郁患者躯体症状及认知功能,其机制可能与相互促进和维持大脑内神经递质的释放有关,对脑小血管病的防治具有一定的意义。     

电针结合磁刺激对脑缺血大鼠脑组织含水量和细胞外钙离子浓度的影响

目的 观察电针结合磁刺激对急性脑缺血大鼠脑组织含水量和细胞外钙离子含量的影响。方法 将30只雄性Wistar大鼠随机分成5组：正常组、模型组、电针组、磁刺激组和电针加磁刺激组，每组6只。制作急性大脑中动脉缺血模型，分别施以电针、磁刺激和电针加磁刺激，检测脑组织含水量和局部细胞外钙离子浓度。结果 单纯电针或磁刺激均能降低脑组织含水量和遏止细胞外钙离子浓度降低，而2者合用效果更优。结论 电针结合磁刺激能较好地改善急性脑缺血大鼠脑组织水肿和良性调节细胞外钙离子浓度。     

电针联合经颅磁刺激对急性脑缺血大鼠VEGF及其受体Flk-1表达的影响

目的观察电针联合经颅磁刺激对急性脑缺血大鼠血管内皮生长因子(VEGF)及其受体Flk-1表达的影响.方法将25只雄性Wistar大鼠随机分成5组正常组、模型组、电针组、磁刺激组和电针加磁刺激组.制造大鼠急性大脑中动脉缺血模型后,各治疗组分别施以电针、磁刺激和电针加磁刺激处理,采用免疫组织化学方法观察不同干预方法对VEGF及Flk-1表达的影响.结果免疫组织化学染色结果显示,模型组梗死灶周围VEGF和Flk-1的表达较正常组明显增强(P＜0.05);电针组、磁刺激组和电针加磁刺激组VEGF和Flk-1的表达与模型组比较,均明显增强(P＜0.05),尤以电针加磁刺激组为明显(P＜0.01).结论电针或磁刺激治疗均可增强急性脑缺血大鼠梗死灶周围VEGF和Flk-1的表达,从而减轻缺血后脑损伤,促进脑功能的康复,二者联合应用疗效更佳.     

MRI研究轻度认知障碍大脑连接改变及其机制进展

阿尔茨海默病(AD)是进行性发展的神经退行性疾病;轻度认知障碍(MCI)是正常衰老与痴呆之间的过渡状态,为预防性治疗AD的关键阶段。弥散张量成像(DTI)和血氧水平依赖功能MRI(BOLD-fMRI)常用于评估大脑结构及功能连接及解释其相关机制。本文就MRI研究MCI大脑连接改变及其机制进展进行综述。     

An electrophysiological link between the cerebellum, cognition and emotion: frontal theta EEG activity to single-pulse cerebellar TMS

Early intracranial electrical stimulation studies in animals demonstrated cerebellar connectivity to brain structures involved in cognitive and emotive functions. Human electrophysiological data to support cerebellum involvement in the latter functions are however lacking. In the present study, electrophysiological responses were recorded to single-pulse transcranial magnetic stimulation (TMS) over the vermis in healthy human volunteers. Increased theta activity was observed after single-pulse vermis TMS as compared to sham and occipital TMS. Both animal and human research relate theta activity with the septo-hippocampal complex, an important brain structure involved in cognition and emotion. The present electrophysiological study supports the earlier intracranial electrical stimulation findings by demonstrating cerebellar involvement in the modulation of the core frequencies related to cognitive and emotive aspects of human behavior.     

长程经颅磁刺激对脑梗死大鼠皮质脑源性神经营养因子表达及神经功能恢复的影响

目的探索长程经颅磁刺激（TMS）对脑梗死大鼠梗死灶周围皮质脑源性神经营养因子（BD-NF）表达和脑损伤体积、神经功能恢复的影响及作用机制，为经颅磁刺激在脑梗死治疗及康复中的应用提供理论依据。方法TMS组与假刺激组大鼠各48只，于大脑中动脉阻塞／再灌注（MCAO／R）90min后的3周内每日接受1次TMS（200脉冲）与假刺激治疗。检测2组大鼠神经功能恢复情况、梗死灶周围皮质BDNF免疫阳性细胞表达及脑损伤体积，对所得资料进行统计学分析。结果在治疗2周和3周时，TMS组神经功能缺损评分与假刺激组相比均明显降低（P〈0．01）。TMS组在治疗3d、7d、14d、21d时梗死灶周围皮质BDNF阳性细胞计数与假刺激组各对应时间点相比，差异均有统计学意义（P〈0．01），且2组治疗21d时梗死灶周围皮质BDNF阳性细胞计数与大鼠神经功能缺损评分呈显著负相关（r=-0．877，P〈0．01）。治疗3周后，TMS组脑损伤体积明显小于假刺激组（P〈0．05），2组脑损伤体积与最终神经功能缺损评分明显相关（r=0．859，P〈0．01）。结论长程TMS有促进脑梗死大鼠神经功能缺损恢复的作用，其作用通过持续上调梗死灶周围皮质BDNF阳性细胞表达、减小梗死后脑损伤体积等作用而实现。     

Examining cortical dynamics and connectivity with simultaneous single-pulse transcranial magnetic stimulation and fast optical imaging

Transcranial magnetic stimulation (TMS) is a widely used experimental and clinical technique that directly induces activity in human cortex using magnetic fields. However, the neural mechanisms of TMS-induced activity are not well understood. Here, we introduce a novel method of imaging TMS-evoked activity using a non-invasive fast optical imaging tool, the event-related optical signal (EROS). EROS measures changes in the scattering of near-infrared light that occur synchronously with electrical activity in cortical tissue. EROS has good temporal and spatial resolution, allowing the dynamics and spatial spread of a TMS pulse to be measured. We used EROS to monitor activity induced in primary motor cortex (M1) by a TMS pulse. Left- and right-hand representations were mapped using standard TMS procedures. Optical sources and detectors mounted on thin rubber patches were then centered on M1 hand representations. EROS was recorded bilaterally from motor cortex while unilateral TMS was simultaneously delivered. Robust ipsilateral EROS activations were apparent within 16 ms of a pulse for TMS delivered to both left and right hemispheres. Clear motor evoked potentials (MEPs) were also elicited by these TMS pulses. Movement artifacts could be excluded as a source of EROS, as no activation was present on short-distance optical channels. For left hemisphere TMS subsequent (40 ms) contralateral activity was also present, presumably due to trans-synaptic propagation of TMS-evoked activity. Results demonstrate that concurrent TMS/EROS is a viable and potentially powerful method for studying TMS-induced activity in the human brain. With further development, this technique may be applied more broadly in the study of the dynamics of causal cortico-cortical connectivity.     

Positron emission tomography during transcranial magnetic stimulation does not require mu-metal shielding

Recording brain activity using positron emission tomography (PET) during the stimulation of different parts of the brain by transcranial magnetic stimulation (TMS) permits the mapping of neural connections in the living human brain. However, controversy remains regarding the need for micro-metal shielding of the PET scanner during magnetic stimulation. The aim of this study was to test the effects of magnetic fields generated by TMS on PET data acquisition. With TMS-on and -off in the PET field of view, transmission scans with a (68)Ge/(68)Ga pin source and emission scans with an uniform phantom filled with water and (18)F were acquired. The frequency and intensity of stimulation were set at 3-5 Hz and 70-80% of the maximum output of the stimulator, respectively. The TMS coil was placed at several locations inside the PET gantry, and the main field direction of the TMS coil was varied between parallel and perpendicular orientation to the scanner's axis. Qualitative and quantitative evaluation of the sinograms of transmission PET scans and reconstructed emission images indicated no measurable differences between TMS-on and -off and post-TMS conditions for any position or orientation. The long distance between the TMS coil and the detector block in the PET scanner, as well as the rapid reduction of the magnetic field with distance (3% of maximum field at 10 cm, in air), could explain the lack of TMS interference. The brief duration (approximately 250 micros) of the TMS pulses relative to the total PET acquisition time would also explain the lack of TMS effects. The lack of TMS effects on the PET scanner, as well as PET imaging without any shielding, has been reported by other laboratories.     

动脉自旋标记成像用于轻度认知障碍研究进展

轻度认知障碍（MCI）是阿尔茨海默病（AD）的前驱期，对其发病机制尚不明确。脑血流量是衡量脑功能的重要指标，各种原因致局部脑血流量（rCBF）减低而损伤大脑。动脉自旋标记（ASL）MRI是通过磁化标记动脉血中氢质子作为内源性示踪剂测量rCBF的成像技术。本研究针对ASL成像在早期诊断MCI、监测疾病进展及评估疗效中的研究进展进行综述。     

Transcranial Magnetic Stimulation for Migraine: A Safety Review

(Headache 2010;50:1153‐1163) Objective.— To review potential and theoretical safety concerns of transcranial magnetic stimulation (TMS), as obtained from studies of single‐pulse (sTMS) and repetitive TMS (rTMS) and to discuss safety concerns associated with sTMS in the context of its use as a migraine treatment. Methods.— The published literature was reviewed to identify adverse events that have been reported during the use of TMS; to assess its potential effects on brain tissue, the cardiovascular system, hormone levels, cognition and psychomotor tests, and hearing; to identify the risk of seizures associated with TMS; and to identify safety issues associated with its use in patients with attached or implanted electronic equipment or during pregnancy. Results.— Two decades of clinical experience with sTMS have shown it to be a low risk technique with promise in the diagnosis, monitoring, and treatment of neurological and psychiatric disease in adults. Tens of thousands of subjects have undergone TMS for diagnostic, investigative, and therapeutic intervention trial purposes with minimal adverse events or side effects. No discernable evidence exists to suggest that sTMS causes harm to humans. No changes in neurophysiological function have been reported with sTMS use. Conclusions.— The safety of sTMS in clinical practice, including as an acute migraine headache treatment, is supported by biological, empirical, and clinical trial evidence. Single‐pulse TMS may offer a safe nonpharmacologic, nonbehavioral therapeutic approach to the currently prescribed drugs for patients who suffer from migraine.