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目的利用功能磁共振成像(fMRI)对皮质下脑梗死运动功能恢复的神经机制进行探讨。方法选择运动功能恢复较好的慢性期单侧皮质下脑梗死患者23例为患者组,年龄匹配的健康志愿者24例为对照组。用FuglMeyer量表评价患者的运动功能。fMRI实验采用组块设计,分别进行双手虚握拳运动,采用统计参数图比较2组执行手运动任务时脑激活的异同。结果对照组及患者组健手运动主要激活运动对侧感觉运动区、同侧小脑半球及双侧辅助运动区。患者组患手运动激活部位与对照组相同。与对照组比较,患者组患手运动时病灶侧初级运动皮质(M1)激活增强。结论在运动通路皮质下脑梗死患者运动功能恢复中,病灶侧M1区激活增强起重要作用。 相似文献
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磁共振成像检测心脏功能研究的进展 总被引:2,自引:0,他引:2
磁共振成像检测心脏功能研究的进展贺峰汪家瑞利用生物组织中的'H在主磁声中被激励后产生的磁共振(MR)现象,能得到很强的质子MR信号,从而可以进行磁共振成像(MRI)。80年代初心门控磁共振成像(ECG-MRI)应用,得到了清晰的心脏MR影像。与X线不... 相似文献
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张明园等对上海地区居民进行的流行病学调查发现,阿尔茨海默病(AD)发病率55岁蹦上为0.42%,60岁以上为0.56%,65岁以上为0.89%,AD约占所有痴呆患者的50%-70%。目前AD尚无公认的单一牛物学指标可以确诊,最终确诊需进行病理组织学检查。目前,对轻度AD患者仍有望改善症状,延缓病情发展。因此,AD的早期诊断和早期干预是研究热点。1990年代以来,功能磁共振成像(functional magnetic resonance imaging,fMRI)逐步发展成为一种全新技术,将神经代谢活动的检测与高分辨率成像技术结合起来,能够准确地对神经元活动进行定位,并且具有不使用放射性同位素示踪剂、无创、可反复检查等优点。应用fMRI对认知功能的研究,为AD患者早期诊断、早期治疗带来了新的希望,对认知功能领域的研究也做了许多有意义的贡献。本文简述fMRI应用对AD认知方面的研究进展。 相似文献
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目的 探讨正常健康老年人数字工作记忆的脑加工神经机制.方法 实验采用事件相关设计,利用功能磁共振技术(fMRI)对15例正常老年人进行数字工作记忆的数据采集,数据采用AFNI 软件进行数据分析和脑功能区活动图像,分析编码期、保持期、提取期的脑激活情况.结果 进行数字记忆工作任务时,15例正常老年人平均反应时为(1 102.4±99.3)ms,正确率为(95.2±2.5)%.数字工作记忆的编码期激活双侧中央前回、双侧梭状回、双侧枕下回、双侧小脑;保持期脑激活位于左侧中央前回、中央后回、岛叶、额下回及额中回、双侧壳核、双侧梭状回及右额下回也有少量激活;提取期脑激活位于双侧壳核、双侧丘脑、双侧岛叶、双侧顶下小叶、左侧额下回、左侧中央后回、左侧颞中回、左侧颞下回、双侧小脑.结论 左侧额叶在正常老年人脑数字工作记忆中起重要作用,其他脑区也共同参与完成数字工作记忆的信息处理过程. 相似文献
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磁共振电影成像评价左右心室整体收缩功能 总被引:6,自引:1,他引:6
目的对照超声心动图研究磁共振(MR)电影成像评价左右心室功能的应用价值。方法应用屏气真实稳定进动快速成像(TrueFISP)电影序列和右室改良定位方法对36名健康成人志愿者进行MRI检查,以及超声心动图左心功能对照检查。MRI图像经Argus心脏功能软件进行左右室功能的分析及评价。结果(1)MRI测量正常组的左心室整体收缩功能各指标:舒张末期容积(EDV)为(101.3±19.2)ml,收缩末期容积(ESV)为(42.1±13.3)ml,每搏输出量(SV)(69.2±9.8)ml,射血分数(EF)(59.1±7.2)%;右心室整体收缩功能EDV(118.9±27.1)ml,ESV(57.6±16.1)ml,SV(61.2±12.7)ml,EF(51.9±4.5)%。(2)MRI测量左心功能与超声心动图检查结果对照:EDV与超声心动图测值[(97.2±17.6)ml]比较,差异无统计学意义;ESV测值大于超声心动图测值[(33.2±9.4)ml],其余指标均低于超声检查[SV为(64.0±11.3)ml,EF为66.1%±6.2%,P<0.01]。两种方法各指标测量值相关性良好(r=0.66~0.80,P<0.05)。(3)右心室短轴定位改良前后心功能指标测值比较:除ESV测值与改良前差异无统计学意义外,EDV、SV、EF均明显大于改良前(P<0.05)。结论MRI是综合准确无创的心脏检查技术。其电影成像技术结合改良定位对左右心室功能测量准确,兼获心脏解剖和形态信息,可以用于心脏疾病的功能评价及疗效监测。 相似文献
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<正> 运动功能受损是脑卒中后最严重的功能障碍,约3/4患者遗留不同程度运动功能缺损,主要是神经元及其传导系统的功能与结构发生异常。运动功能恢复机制的研究,对运动功能障碍患者能够提供科学的康复手段。功能磁共振成像(functional magnetic resonance imaging,fMRI)在功能上反映大脑皮质功能区在执行某项任务或受到某种刺激时的 相似文献
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失语症的功能性神经影像学 总被引:2,自引:0,他引:2
文章从4个方面综述了失语症患者的功能神经影像学:(1)Broca区损害对其远隔非损害区域的影响;(2)正常情况下被激活的皮质区受损后,患者如何保持其语言功能从而显示组成脑功能系统的必需部位和充分部位;(3)伴随深层失读的失语症患者右半球阅读是否属于神经系统的副本;(4)语言功能恢复的机制。 相似文献
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磁共振弥散张量成像在神经疾病中的应用 总被引:4,自引:0,他引:4
磁共振弥散张量成像(DT)是近几年发展起来的水弥散成像技术,它通过脑水分子的弥散性定量反映脑白质纤维束的完整性。文章简要介绍了DTI的基本概念及其在脑梗死、多发性硬化、癫痫、Alzheimer病和颅内肿瘤等多种神经疾病中的应用。 相似文献
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血管性痴呆的磁共振检查 总被引:1,自引:0,他引:1
腔隙和脑白质异常改变一直被认为是血管性痴呆的主要因素。MRI能较早发现这些变化。然而,在临床上痴呆的诊断与影像学表现程度的不一致性和滞后性使人们更多地关注与认知障碍密切相关的海马及其病理变化。文章从MRI和磁共振波谱分析角度对腔隙、脑白质异常和海马在血管性痴呆中的病理和代谢变化作了综述,强调海马的形态和代谢改变在血管性痴呆发病机制中的重要价值。 相似文献
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汉字阅读加工的功能磁共振研究进展 总被引:1,自引:0,他引:1
对阅读基本机制的了解是研究失读症发病机制和对失读症进行康复治疗的基础。功能磁共振成像是一种能显示活体脑内神经活动状态的成像方法,近年来被用于语言学尤其是汉字阅读加工机制的研究。本文对汉字单字加工的偏侧化以及是否存在汉字认知加工的特异脑区等进行综述。 相似文献
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Unknowns about the neurophysiology of normal and disordered swallowing have stimulated exciting and important research questions.
Previously, these questions were answered using clinical and animal studies. However, recent technologic advances have moved
brain-imaging techniques such as functional magnetic resonance imaging (fMRI) to the forefront of swallowing neurophysiology
research. This systematic review has summarized the methods and results of studies of swallowing neurophysiology of healthy
adults using fMRI. A comprehensive electronic and hand search for original research was conducted, including few search limitations
to yield the maximum possible number of relevant studies. The participants, study design, tasks, and brain image acquisition
were reviewed and the results indicate that the primary motor and sensory areas were most consistently active in the healthy
adult participants across the relevant studies. Other prevalent areas of activation included the anterior cingulate cortex
and insular cortex. Review limitations and suggested future directions are also discussed.
This research was supported by the National Institutes of Health (NIH), NCRR K12 Roadmap, Training and Education to Advance
Multidisciplinary-Clinical-Research (TEAM) Program. Project number 8K12RR023268-02. 相似文献
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近年来的研究表明,右侧半球可能对左侧半球的语言处理有调节作用。文章综述了优势半球卒中失语右侧半球的代偿机制以及重复经颅磁刺激右侧半球对语言功能康复的影响。 相似文献
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颅内出血的磁共振成像 总被引:3,自引:0,他引:3
MRI的常规序列T1加权成像、T2加权成像和液体衰减反转恢复(FLAIR)序列均可敏感地检出亚急性期和慢性期颅内出血;梯度回波成像可检出各期颅内出血,但血肿信号强度与血肿存在的时间无相关性。弥散加权成像和表观弥散系数能提供更多有关血肿中心区、周围区和梗死后出血的信息。 相似文献
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D. Tombari M.C. Ricciardi N. Bonaffini M. Pasquini M. Cecconi V. Di Piero 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2013,35(3-4):301-307
Stroke is the first cause of disability in industrialized countries. Thus, understanding the mechanisms of poststroke recovery appears to be crucial in improving motor performance and reducing disability in stroke patients. Strategies through which brain restores lost functions after ischemic lesions are numerous. The mechanisms underlying poststroke recovery, known as cerebral plasticity, are so far hypothetical. However, functional magnetic resonance imaging (fMRI) studies recently have provided new insights in to stroke recovery. This article sketches out the mechanisms that are thought to underly recovery and focuses on fMRI experimental studies that have investigated the influence of a number of drugs on functional recovery. Functional MRI is a valuable tool in understanding functional recovery and may help to disclose new therapeutical approaches. 相似文献
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Rofsky NM 《Echocardiography (Mount Kisco, N.Y.)》1996,13(2):183-196
Magnetic resonance imaging (MRI) is well-suited for imaging the vascular system and is of particular value in assessing the anatomy and pathologies of the thoracic aorta. The intrinsic contrast between the blood pool and the vascular structures allows excellent depiction of intra- and extravascular anatomy and eliminates the need for intravenous contrast agents. A large field of view provides a complete evaluation of the mediastinum and chest. Both qualitative and quantitative techniques are available, which can yield physiological data in addition to anatomical information. The multiplanar capability offers images in any plane, allowing an accurate assessment of the longitudinal extent of disease and providing images perpendicular to vessels, even when tortuous. MRI currently represents an essential component of the imaging strategies available to assess the thoracic aorta and may come to function as a gold standard for certain conditions. As the technology continues its rapid evolution, MRI will most likely be able to serve as an effective noninvasive evaluation to provide all of the anatomical, pathological, and physiological information required of a comprehensive examination of the thoracic aorta. 相似文献
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Cardiac thrombus provides a substrate for embolic events and an indication for anticoagulant therapy. Cardiac magnetic resonance (CMR) imaging enables thrombus to be detected based on intrinsic tissue characteristics related to avascular tissue composition. Delayed enhancement CMR tissue characterization has been well validated for thrombus assessment using references of both pathology and clinical thromboembolic outcomes. Comparative studies have demonstrated CMR to yield improved thrombus detection compared to echocardiography, which typically detects thrombus based on anatomic appearance. Experimental studies have demonstrated the feasibility of targeted CMR contrast agents for assessing thrombus composition and chronicity. This review examines established and emerging literature on use of CMR for assessing cardiac thrombus. 相似文献