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1.
脑功能区病变术前运动功能的评估   总被引:3,自引:0,他引:3  
目的探讨功能磁共振成像(Functional Magnetic Resonance Imaging,fMRI)在脑运动区病变患者术前评估和手术设计中的作用。方法20例累及运动区的脑内占位病变患者,术前采用手握拳运动block激发模式,fMRI获取运动激活信号,术前分析病变与运动区的关系及功能重组织类型。结果病变位于中央前回前或后15例,fMRI均表现为病变对侧第一运动区(Primary Motor Area,M1)激活并向后或向前移位,病灶边缘与激活信号之间的最小距离为5~9mm,平均9.6mm。病变位于中央前回5例,表现为瘤周激活3例,运动前区激活并皮层弥散激活2例。结论fMRI有助于神经外科医师在术前对病变与功能区的关系及皮层功能重组织类型有较好的认识,对运动区病变术前评估和手术设计有重要指导价值。  相似文献   

2.
目的 探讨弥散张量成像在定位初级运动功能区的价值.方法 20例脑深部肿瘤患者,分别进行常规MRI、fMRI及DTI检查,获取fMRI脑激活图、DTI图、3D解剖图.DTI通过三维重建皮质脊髓束定位初级运动功能区.fMRI采用手握拳激发模式,获取激活信号定位初级运动功能区.比较两种技术的吻合度,以评价DTI三维重建皮质脊髓束定位的初级运动功能区的准确性.结果 20例患者fMRI获得的激活信号主要位于对侧中央沟处,围绕着"Ω"形柄状结构分布,中央前回位于激活信号前方.所有患者均成功地完成DTI皮质脊髓束的三维重建,重建的皮质脊髓束也定位于激活信号前的脑回,两者均较好显示初级运动功能区且具有较好的一致性.结论 DTI可较好地定位初级运动功能区,这对于有肢体瘫痪患者及不能合作的儿童的初级运动功能区的定位有重要意义.  相似文献   

3.
目的探讨急性缺血性卒中患者运动皮质激活模式和功能重组改变。方法采用f MRI观察22例急性缺血性卒中患者进行对指运动任务时的运动皮质激活模式和功能重组改变,采用美国国立卫生研究院卒中量表(NIHSS)评价神经功能、Fugl-Meyer上肢评价量表(FMA-UE)评价上肢运动功能,神经电生理学监测静息运动阈值。采用Spearman秩相关分析探讨兴趣区激活强度与神经功能、运动功能和神经电生理学的相关性,动态因果模型分析对指运动时双侧大脑半球间和大脑半球内有效连接。结果急性缺血性卒中患者患侧对指运动主要表现为患侧初级运动皮质、运动前区皮质和双侧辅助运动区激活,同时伴健侧运动前区皮质、后顶叶皮质和双侧小脑半球少量激活;健侧对指运动主要表现为健侧初级运动皮质、运动前区皮质和辅助运动区激活,同时伴患侧辅助运动区、顶下小叶少量激活。患侧初级运动皮质激活强度值与神经功能(NIHSS评分)呈负相关(r_s=-0.452,P=0.035)、与上肢运动功能(FMA-UE评分)呈正相关(r_s=0.543,P=0.009),患侧感觉运动皮质激活强度值与患侧静息运动阈值呈正相关(r_s=0.718,P=0.001)。在动态因果模型所示优势模型中,双侧初级运动皮质间存在双向负性有效连接;健侧辅助运动区对健侧初级运动皮质存在负性有效连接,对患侧初级运动皮质存在正性有效连接;患侧辅助运动区对健侧辅助运动区存在正性有效连接。健侧初级运动皮质对患侧初级运动皮质的有效连接强度值与上肢运动功能(FMA-UE评分)呈负相关(r_s=-0.461,P=0.047),健侧辅助运动区对健侧初级运动皮质的有效连接强度值与上肢运动功能(FMA-UE评分)呈正相关(r_s=0.533,P=0.041)。结论f MRI结合神经功能和运动功能评价及神经电生理学监测可以有效观察急性缺血性卒中患者运动皮质激活模式和功能重组改变,为理解脑卒中运动障碍和功能重组以及进行康复治疗提供指导。  相似文献   

4.
目的 应用脑功能磁共振成像(fMRI)技术,观察书写痉挛患者痉挛性书写脑功能区激活特点,探讨书写痉挛可能发病机制.方法 采用fMRI组块设计,分别获得10例书写痉挛患者和10名年龄、性别匹配健康对照组执行默写、手写、笔写任务时的平均脑功能激活图,同时通过一般线性分析法产生“笔写减手写”及“笔写减默写”的差异脑功能图.结果 书写痉挛患者进行书写任务时,受累手对侧基底节区,特别是壳核(激活体素个数864),较健康对照组(激活体素个数54)显著激活;运动皮质(第一运动区、辅助运动区、运动前区)及同侧小脑较健康对照亦有明显激活;而进行手指写和默写任务时两组间差异并不明显;"笔写减手写"及"笔写减默写"差异脑功能图发现书写痉挛患者在除去手指写运动及语言处理相关影响后上述脑区仍有明显激活,健康对照组则皮质下结构激活消失,运动相关皮质激活亦明显减少.结论 书写痉挛患者执行笔写任务时上述脑区尤其皮质下结构异常激活与书写痉挛发生存在一定关联,基底节区及相应皮质-皮质下环路功能紊乱,可能在书写痉挛发病机制中起到重要作用.  相似文献   

5.
正常成人皮质吞咽中枢功能磁共振的初步研究   总被引:1,自引:0,他引:1  
目的探讨正常成人皮质吞咽中枢的分布与特点。方法采用血氧水平依赖(BOLD)的功能磁共振方法对6例右利手健康志愿者进行吞咽中枢的定位。在GE公司3.0T磁共振仪上,除常规T1、T2扫描外,患者行吞咽动作,获取BOLD信号变化。扫描时间共60秒,在第1、15、30、45秒时受试者分别完成一次空吞咽动作,吞咽时尽量减少唇、舌、头部的运动。采用SPM软件在Functool4.0工作站上对图像数据进行后处理。结果正常受试者吞咽动作的激活部位位于感觉运动皮质外侧、岛叶、扣带回前部、运动前区,眶额皮质、小脑。仅有岛叶的激活信号以左侧半球为著。结论正常成人的吞咽中枢位于多个脑区。自主吞咽动作的启动及调节需要多个脑区的激活。  相似文献   

6.
T2灰阶反转图像在神经外科手术中的应用   总被引:1,自引:0,他引:1  
目的 总结评价T2灰阶反转图像在神经外科手术中的作用.方法 将常规磁共振T2图像融合在神经导航中,并进行灰阶反转处理.对36例神经外科手术患者,采朋T2厌阶反转图像进行脑沟、脑回等结构定位,并在13例功能区肿瘤手术中.对体感诱发电位、皮质直接电刺激对中央沟、中央前回手区的定位结果与T2灰阶反转图像定位结果进行比较.结果 T2灰阶反转图像在显示脑沟、脑回、脑表面浅静脉等结构,以及脑水肿范围上比其他序列网像清晰.应用T2灰阶反转网像导航定位中央沟及中央前回手运动区在此组病例中与体感诱发电位、皮质直接电刺激结果完全符合.结论 T2灰阶反转图像对脑沟、脑回等脑结构的显示、定位可靠,可以替代神经电生理对中央沟的空间定位,并为图像引导的神经外科手术提供了更丰富的网像信息.  相似文献   

7.
目的通过功能MRI成像(fMRI)技术对大脑半球弥漫性病变致癫痫患者的患侧大脑半球的功能残存情况和健侧大脑半球的功能代偿情况进行综合评估,从而选择合理的手术方案。方法受试者为15例一侧大脑半球弥漫性病变致癫痫的患者,任务包括右手抓握运动、左手抓握运动、右脚抓握运动、左脚抓握运动、舌运动、默读语言等6项,采集fMRI数据并进行统计学分析,获取相应的皮质激活区图像。4例行解剖性大脑半球切除术,11例行多脑叶切除术。结果患侧手运动时的信号激活,6例在双侧半球相应区域;2例信号较弱,无明显激活区域;2例在健侧半球;5例在患侧半球。患侧脚运动时,8例信号激活在双侧半球相应区域;1例信号较弱,无明显激活区域;4例在健侧半球;2例在患侧半球。术后13例偏瘫无明显加重。术后随访20~52个月,12例癫痫控制为EngelⅠA级,2例为EngelⅡA级,1例为EngeⅢA级。结论fMRI能够客观地评估顽固性癫痫患者运动功能的保留和代偿情况,是一种有效且无创的评估手段。  相似文献   

8.
术中皮质体感诱发电位与电刺激术定位脑功能区   总被引:13,自引:3,他引:10  
目的探讨脑功能区手术中利用脑皮质体感诱发电位(SEP)及直接皮质电刺激定位脑功能区的方法及意义。方法对10例脑功能区病变病人在唤醒麻醉下进行手术,利用皮质SEP及皮质直接电刺激定位感觉区、运动区及语占区,住保护脑功能区的前提下,手术切除病变。结果7例病人利用SEP及皮质电刺激确定出运动感觉区,其中4例利用SEP位相倒置确定出中央沟,3例病变位于左侧额颞叶的病人通过皮质直接电刺激确定出语言区?术后功能均较术前明显好转。结论术中SEP及直接皮质电刺激可准确、实时确定脑功能区,最大程度地保护功能,切除病变。  相似文献   

9.
正1病例资料女,31岁,因检查发现右侧额叶占位半年入院。入院体格检查未见阳性体征。头颅MRI显示右侧额上回肥大、皮髓质层次破坏,累及中央前回;T1WI呈低信号,T2WI呈稍高信号,增强后无明显强化;病灶大小约为7.5 mm×5.5 mm(图1A)。磁共振弥散张量成像显示大脑皮质脊髓束未见纤维束中断、破坏、移位。磁共振血氧依赖性饱和成像显示邻近肿瘤内侧的中央旁小叶有皮层运动功能激活表现。术前行多模态神经影像融合,显示肿瘤主体位于运动前区,累及中央前回,部分激活的运动皮层位于肿瘤后方,肿瘤被锥体束包绕,未见肿瘤浸润锥体束及明显的锥体束推移(图1B)。3D  相似文献   

10.
目的应用fMRI技术探讨中国青年和老年人群在简单运算任务下脑激活模式及其与行为学之间的关系。方法分别对青年组(19例)和老年组(20例)健康志愿者进行对照任务和简单运算任务下的fMRI检查。结果两组受试者受教育程度(P=0.125)、智力水平(P=0.921),以及完成对照任务(P=0.142)和简单乘法运算任务(P=0.880)之正确率差异无统计学意义,但老年组受试者完成对照任务(P=0.000)和简单乘法运算任务(P=0.005)反应时间明显延长。青年组受试者在任务刺激下可激活右侧缘上回并向顶内沟和颞中上回后部延伸,中央前回和运动前区、前额叶,左侧缘上回并向颞上回后部和角回延伸,顶内沟区域、颞中下回,内侧后扣带回、楔前叶、辅助运动区、海马沟、海马旁回及前额叶内侧;老年组受试者则分别激活右侧缘上回和顶下区域并向颞中上回后部延伸,中央前回和运动前区、前额叶,左侧缘上回和角回并向顶下延伸,中央前回和运动前区、岛叶及前额叶,内侧后扣带回和中央旁小叶、前扣带回及前额叶内侧;两组受试者共激活脑区包括顶下区域、楔前叶、中央前后回和额顶叶网络,以及颞叶、海马旁回、钩回、屏状核和后扣带回等皮质下结构。结论数学事实提取相关网络的主要成分受年龄影响较小,老年人群的任务激活脑区主要向任务相关顶区集中。  相似文献   

11.
BACKGROUND: Functional MRI (fMRI) demonstrates the localization of hand representation in the motor cortex, thereby providing feasible noninvasive mapping of functional activities in the human brain.
OBJECTIVE: To observe cortical activation within different cortical motor regions during repetitive hand movements in healthy subjects through the use of fMRI.
DESIGN: An observational study, with each subject acting as his own control.
SETTING: Department of Radiology, the First Affiliated Hospital of Nanchang University.
PARTICIPANTS: Seven healthy volunteers, 4 males and 3 females, aged 19 to 38 years, participated in the study. All subjects were right-handed, with no neurological or psychological disorders. Informed written consent was obtained from all subjects, and the study was approved by the Institutional Review Board of the First Affiliated Hospital of Nanchang University.
METHODS: The study was performed at the Department of Radiology between June-August 2005. A 1.5 Tesla Siemens MRI scanner (Symphony, Germany) was used to acquire T1-weighted structural images, which were oriented parallel to the line running through the anterior and the posterior commissures. Subjects were instructed on a task and were allowed to practice briefly prior to the imaging procedure. The motor activation task consisted of the right hand performing a clenching movement. The T1-W images were acquired from six alternating epochs of rest and activation from all seven healthy subjects. Data were collected with echoplanar imaging of brain oxygen level dependent (BOLD) sequence. Each series comprised six cycles of task performance (30 seconds), alternating with rest (30 seconds) periods, and 3-second time intervals. The differences between active and baseline fMRI imaging were calculated using the student t-test. Differential maps were overlaid on the high resolution TI-W structural image for neuroanatomical correlation of activation areas.
MAIN OUTCOME MEASURES: The omega-shaped hand knob  相似文献   

12.
Ipsilateral involvement of primary motor cortex during motor imagery   总被引:7,自引:0,他引:7  
To investigate whether motor imagery involves ipsilateral cortical regions, we studied haemodynamic changes in portions of the motor cortex of 14 right-handed volunteers during actual motor performance (MP) and kinesthetic motor imagery (MI) of simple sequences of unilateral left or right finger movements, using functional magnetic resonance imaging (fMRI). Increases in mean normalized fMRI signal intensities over values obtained during the control (visual imagery) task were found during both MP and MI in the posterior part of the precentral gyrus and supplementary motor area, both on the contralateral and ipsilateral hemispheres. In the left lateral premotor cortex, fMRI signals were increased during imagery of either left or right finger movements. Ipsilateral cortical clusters displaying fMRI signal changes during both MP and MI were identified by correlation analyses in 10 out of 14 subjects; their extent was larger in the left hemisphere. A larger cortical population involved during both contralateral MP and MI was found in all subjects. The overall spatial extent of both the contralateral and the ipsilateral MP + MI clusters was approximately 90% of the whole cortical volume activated during MP. These results suggest that overlapping neural networks in motor and premotor cortex of the contralateral and ipsilateral hemispheres are involved during imagery and execution of simple motor tasks.  相似文献   

13.
We evaluated a 63 year-old, right-handed woman by functional MRI (fMRI) in the early and the recovery stages following a cerebral infarction in the right precentral knob. An activated signal in the ipsilateral sensorimotor cortex and contralateral supplementary motor cortex during deteriorated hand grasping (left) was observed in the early stages, whereas being unable to detect in the functionally recovered period. When simultaneous bilateral hand grasping was performed, the activated signal around infarct region was enlarged in recovered period. The functionally neural reorganization processes relating recovered hand movement after localized cortical infarction (precentral knob) was suggested.  相似文献   

14.
We describe a novel spatial filtering approach to the localization of cortical activity accompanying voluntary movements. The synthetic aperture magnetometry (SAM) minimum-variance beamformer algorithm was used to compute spatial filters three-dimensionally over the entire brain from single trial neuromagnetic recordings of subjects performing self-paced index finger movements. Images of instantaneous source power ("event-related SAM") computed at selected latencies revealed activation of multiple cortical motor areas prior to and following left and right index finger movements in individual subjects, even in the presence of low-frequency noise (e.g., eye movements). A slow premovement motor field (MF) reaching maximal amplitude approximately 50 ms prior to movement onset was localized to the hand area of contralateral precentral gyrus, followed by activity in the contralateral postcentral gyrus at 40 ms, corresponding to the first movement-evoked field (MEFI). A novel finding was a second activation of the precentral gyrus at a latency of approximately 150 ms, corresponding to the second movement-evoked field (MEFII). Group averaging of spatially normalized images indicated additional premovement activity in the ipsilateral precentral gyrus and the left inferior parietal cortex for both left and right finger movements. Weaker activations were also observed in bilateral premotor areas and the supplementary motor area. These results show that event-related beamforming provides a robust method for studying complex patterns of time-locked cortical activity accompanying voluntary movements, and offers a new approach for the localization of multiple cortical sources derived from neuromagnetic recordings in single subject and group data.  相似文献   

15.
Human activities often involve hand‐motor responses following external auditory–verbal commands. It has been believed that hand movements are predominantly driven by the contralateral primary sensorimotor cortex, whereas auditory–verbal information is processed in both superior temporal gyri. It remains unknown whether cortical activation in the superior temporal gyrus during an auditory–motor task is affected by laterality of hand‐motor responses. Here, event‐related γ‐oscillations were intracranially recorded as quantitative measures of cortical activation; we determined how cortical structures were activated by auditory‐cued movement using each hand in 15 patients with focal epilepsy. Auditory–verbal stimuli elicited augmentation of γ‐oscillations in a posterior portion of the superior temporal gyrus, whereas hand‐motor responses elicited γ‐augmentation in the pre‐ and postcentral gyri. The magnitudes of such γ‐augmentation in the superior temporal, precentral, and postcentral gyri were significantly larger when the hand contralateral to the recorded hemisphere was required to be used for motor responses, compared with when the ipsilateral hand was. The superior temporal gyrus in each hemisphere might play a greater pivotal role when the contralateral hand needs to be used for motor responses, compared with when the ipsilateral hand does. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

16.
功能磁共振与皮层电刺激定位感觉运动区的比较   总被引:2,自引:1,他引:1  
目的 通过功能磁共振(fMRI)与皮层电刺激做点对点的比较,以判断fMRI对感觉运动区定位的精确性,从而评价其在功能定位中的意义及其临床应用价值.方法 对14例EEG示异常放电部位位于感觉运动区的难治性癫痫患者,术前采用双手握拳-伸缩运动任务进行血氧依赖水平(BOLD)扫描,运用BOLD技术的fMRI定位皮质感觉运动区.皮层电极植入术后给予头颅连续无间断CT扫描获取电极与颅骨的对应关系,通过神经导航仪将CT、fMRI影像与导航序列MRI图像融合后,得出含有皮层激活区和电极的融合图像建立三维立体图像,与皮层电刺激.结果进行比较,以评价fMRI定位皮质感觉运动区的准确性.结果 14例fMRI可见激活部位主要分布于对侧中央区、辅助运动区和小脑.其中11例成功完成皮层电刺激,结果显示fMRI与电刺激的吻合率为91.7%.结论 BOLD技术具有较高的敏感性和精确率,对感觉运动区定位有重要的临床应用价值.  相似文献   

17.
目的研究利用三维重建脑表面成像辨识中央前回的方法及其可靠性。方法难治性癫痫经术前评估需要进行颅内电极植入的病例12例,术前行3T磁共振结构像扫描及运动功能磁共振测试,颅内电极植入后行头颅CT扫描。利用磁共振数据,用Brainvoige软件进行脑表面三维重建,并与硬膜下电极CT融合。根据中央前回的形状走行特点,在重建的脑表面上标记中央前回,进而辨识标记术区中央前回。用皮层电刺激和功能磁共振验证所标记中央前回的可靠性。结果 12例均进行了脑表面三维重建,并标记出了中央前回,硬膜下电极CT电极点与三维脑表面融合。统计中央前回上电极点101个,电刺激运动响应73个,响应率72%;对照组中央前回前1cm(统计中央前沟前2个电极范围),130个电极,17个电极有运动响应,响应率13%,p值小于0.05;功能磁共振手的运动100%中央前回有激活,中央前回前无明显激活。电刺激及功能核磁均验证了本研究方法确定中央前回准确可靠。结论脑表面成像辨识中央前回准确可行,可以利用各初级运动皮层分布的距离进行详细的初级运动皮层的绘制定位。  相似文献   

18.
The aim of the present study was to compare the cerebral activation associated with encoding and retrieval in individual subjects with the average activation in the same group of subjects. Twelve volunteers performed two paradigms: 1) intentional encoding of words, and 2) recognition of learned words intermixed with new distracters. Echo-planar magnetic resonance imaging (MRI) of BOLD signal changes was used to compare cerebral activation between active and resting conditions. During encoding, activation of the left precentral gyrus related to the motor response was observed in some subjects. Averaged data showed increased activation of the left precentral gyrus, the supplementary motor area (SMA), the left inferior frontal gyrus and in the left temporo-occipital junction. During recognition, motor response-related activity was found in the precentral cortex and SMA in most subjects. Activation in other brain areas showed considerable interindividual variation. In the entire group, recognition showed activation of the left dorsolateral prefrontal cortex, the precentral gyrus, the SMA, and the temporo-occipital junction. The total amount and the distribution of task-related cerebral activation varies considerably between individuals and might correspond to individual preferences of cognitive strategies. The investigation of these interindividual variations will be an exciting scientific challenge in the near future.  相似文献   

19.
The cortical potentials preceding movement, negative slope (NS'), premovement positivity (PMP), and the initial slope of motor potential (MP), were studied in detail with a 29-channel averaged EEG mapping technique in normal subjects. Self-paced, voluntary movements of the right and left index fingers were performed up to 150 times, and topographic color maps were created from the averaged wave forms. The maps revealed NS' of the dominant hand on the vertex and NS' of the non-dominant hand on the contralateral centroparietal area. PMP appeared on the ipsilateral precentral area, and the initial slope of MP appeared on a small, distinct contralateral precentral area, presumably the hand motor area. The amplitudes of the potentials did not show significant differences between dominant and non-dominant hands. PMP and the initial slope of MP appeared significantly earlier preceding non-dominant hand movement as compared with dominant movement. The findings indicate some difference in cortical activity relating to dominant and non-dominant hand movement.  相似文献   

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