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find Keyword "功能磁共振" 37 results
  • Lennox-Gastaut综合征中的认知网络异常相互作用:可能的癫痫脑病发生机制

    在Lennox-Gastaut(LG)综合征的患者中,持续反复的癫痫活动被认为是导致认知损害的原因(癫痫脑病)。使用同步脑电图-功能磁共振(EEG-fMRI)的影像手段,发现在LG综合征中癫痫放电会涉及大量在正常情况下与认知重要过程相关的网络。因此在LG综合征中,癫痫活动与认知网络相关,患者出现广泛的认知损害。就此提出假设,LG综合征认知网络间的相互作用存在持续异常。使用无任务EEG-fMRI研究了15例LG综合征患者(28.7±10.6岁)和17名健康对照者(27.6±6.6岁)。使用组独立成分分析(Group level independent components analysis,ICA),选定4个网络用于观察(默认模式、背侧注意、执行控制及前显著网络)。对每一研究个体都进行网络内和网络间的功能连接分析后,再对比LG综合征患者和健康对照组的网络行为。为了证明在头皮未检测到放电行为时两组之间仍存在差别(即差别是持续存在的),用足够数据对6例患者进行了放电相关和放电非相关时段的分别分析。在LG综合征中,认知网络特点为: ① 网络内部整合性减少,包括在默认模式的网络中联系更弱;② 网络之间的分离程度减低,包括默认模式和背侧注意网络间更强烈的连接。不论是否有头皮EEG的放电,fMRI上的异常相互作用均存在,表明在没有头皮能检测到的癫痫活动时也可能有异常网络行为的存在。在LG综合征中,认知网络之间相互作用关系是持续异常的。根据临床中LG综合征典型性地出现发病后认知下降,并且在癫痫得到控制后认知可能会有一定改善,该研究结果与提出的假说一致,表明LG综合征的癫痫过程可能导致并且使异常的网络行为延续。癫痫脑病的发生也许是持续存在的认知网络之间相互作用异常所导致的。

    Release date:2017-09-26 05:09 Export PDF Favorites Scan
  • 抑郁症静息态脑功能磁共振成像研究进展

    不同的静息态功能磁共振成像数据分析法各有其特点。多学科交叉、多模态(包括脑结构)的纵向MRI研究,有助进一步阐明抑郁症的发病机制,为临床诊断、疗效评估和预后预测提供客观的影像学标记,为更有效抗抑郁药物的开发提供功能影像学依据。现对不同临床类型成年抑郁症的静息态脑功能磁共振成像研究进展及早期疗效的预测标记作一综述。

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  • Study of the cognition in patients with benign epilepsy of childhood with centrotemporal spikes by using the ReHo, ALFF, fALFF of RS-fMRI

    Objective The ReHo, ALFF, fALFF of resting-state functional magnetic resonance imaging (RS-fMRI) technology were used to study the influencing factors and neural mechanism of cognitive dysfunction in patients with benign epilepsy of childhood with centrotemporal spikes (BECT). Methods Fourteen patients were enrolled (from April 2015 to March 2018) from epilepsy specialist outpatients and Functional Department of Neurosurgery of Tianjin Medical University General Hospital. They underwent the long term VEEG monitoring (one sleep cycle was included at least), the Wechsler Intelligence Scale (China Revised), the head MRI and RS-fMRI examinations. Spike-wave index (SWI), FIQ, VIQ, PIQ scores were calculated. According to full-scale IQ (FIQ), they were divided into two groups: FIQ<90 (scores range from 70 to 89, the average score was 78.3±8.9, 6 cases) and FIQ≥90 (scores range from 90 to 126, the average score was 116.6±12.9, 8 cases). SPSS21.0 statistical software was used to compare the general clinical data and SWI of the two groups, and the correlation between clinical factors and the evaluation results of Wechsler Intelligence Scale was analyzed. The RS-fMRI images were preprocessed and the further data were analysed by two independent samplest-test under the whole brain of regional homogeneity (ReHo), amplitude of low frequency fluctuation (ALFF) and fractional of ALFF (fALFF) methods. The differences of brain activation regions in RS-fMRI between the two groups were observed, and the results of general clinical data, SWI and cognitive function test were compared and analyzed comprehensively. Results The differences of SWI were statistically significant (P<0.05): FIQ<90 group were greater than FIQ≥90 group. The FIQ, VIQ and PIQ of two groups were negatively correlated with SWI (P<0.05). And the FIQ and PIQ were negatively correlated with the total number of seizures (P<0.05). Compared with FIQ≥90 group by two samplet-test based on whole level ReHo, ALFF, fALFF methods, deactivation of brain regions of FIQ<90 group include bilateral precuneus, posterior cingulate and occipital lobe, and enhanced activation of brain regions include left prefrontal cortex, bilateral superior frontal gyrus medial and right precentral gyrus, supplementary motor area, angular gyrus, supramarginal gyrus, middle temporal gyrus, bilateral insular lobe and subcortical gray matter structures. Conclusions Frequent epileptic discharges during slow wave sleep and recurrent clinical episodes were risk factors for cognitive impairment in BECT patients. Repeated clinical seizures and frequent subclinical discharges could cause dysfunction of local brain areas associated with cognition and the default network, resulting in patients with impaired cognitive function.

    Release date:2018-11-21 02:23 Export PDF Favorites Scan
  • Advances in migraine without aura based on resting-state functional MRI

    Migraine is the most common primary headache clinically, with high disability rate and heavy burden. Functional MRI (fMRI) plays a significant role in the study of migraine. This article reviews the main advances of migraine without aura (MwoA) based on resting-state fMRI in recent years, including the exploration of the mechanism of fMRI in the occurrence and development of MwoA in terms of regional functional activities and functional network connections, as well as the research progress of the potential clinical application of fMRI in aiding diagnosis and assessing treatment effect for MwoA. At last, this article summarizes the current distresses and prospects of fMRI research on MwoA.

    Release date:2024-06-24 02:56 Export PDF Favorites Scan
  • Research on Amplitude of Low-frequency Fluctuation in Patients with Major Depression Based on Resting-state Functional Magnetic Resonance Imaging

    We investigated the baseline brain activity level in patients with major depressive disorder (MDD) by amplitude of low-frequency fluctuation (ALFF) based on resting-state functional MRI (fMRI). We examined 13 patients in the MDD group and 14 healthy volunteers in the control group by resting-state fMRI on GE Signa 3.0T. We calculated and compared the ALFF values of the two groups. In the MDD group, ALFF values in the right medial prefrontal were higher than those in control group, with statistically significant differences (P<0.001). ALFF values in the left parietal in the MDD group were lower than those in control group with statistically significant differences (P<0.001). This resting-state fMRI study suggested that the alteration brain activity in the right medial prefrontal and left parietal ALFF contributed to the understanding of the pathophysiological mechanism of MDD patients.

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  • Application of fMRI in combination with Wada test in preoperative assessment of speech function in medically refractory epilepsy

    Objective To investigate the task group’s effectiveness in language evaluation based on the task group's functional Magnetic resonance (fMRI) results’ agreement with the fixation side of the Wada language area. MethodsWe collected 90 patients with intractable epilepsy of 90 patients from December 13, 2018 to January 3, 2020 from the Epilepsy Center of Guangdong 999 Brain Hospital. We used two simple fMRI tasks. Among them, 25 patients completed the Wada experimental examination, and 8 patients completed the electrode implantation and subsequent preoperative language area mapping. Adopt block experimental design, ABBA style presentation, and use AFNI software to process fMRI data, lateralization index calculation, and multiple regression analysis. ResultsfMRI results from 90 patients showed that the results from both the sentence-completion task and the image-naming task were more stable than those from either task. The results were then compared with the results of the “gold standard” Wada test in 25 patients with fMRI-located language dominance in the hemisphere. The results showed that the accuracy of the single task was between 70% and 80%, but the accuracy of the combined results of the two tasks was 93.3%. Conclusions Compared with the results of a single task, the results of multiple fMRI tasks are more stable in the judgment of activation range and language dominance hemisphere. fMRI and Wada language area siding accuracy 93.3%, fMRI task siding valid and replicable.

    Release date:2023-05-04 04:20 Export PDF Favorites Scan
  • The Impact of Mood on the Intrinsic Functional Connectivity

    Although a great number of studies have investigated the changes of resting-state functional connectivity (rsFC) in patients with mental disorders, such as depression and schizophrenia etc, little is known how stable the changes are, and whether temporal sad or happy mood can modulate the intrinsic rsFC. In our experiments, happy and sad video clips were used to induce temporally happy and sad mood states in 20 healthy young adults. We collected functional magnetic resonance imaging (fMRI) data while participants were watching happy or sad video clips, which were administrated in two consecutive days. Seed-based functional connectivity analyses were conducted using the anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC), and amygdala as seeds to investigate neural network related to executive function, attention, and emotion. We also investigated the association of the rsFC changes with emotional arousability level to understand individual differences. There is significantly stronger functional connectivity between the left DLPFC and posterior cingulate cortex (PCC) under sad mood than that under happy mood. The increased connectivity strength was positively correlated with subjects' emotional arousability. The increased positive correlation between the left DLPFC and PCC under sad relative to happy mood might reflect an increased processing of negative emotion-relevant stimuli. The easier one was induced by strong negative emotion (higher emotional arousability), the greater the left DLPFC-PCC connectivity was indicated, the greater the instability of the intrinsic rsFC was shown.

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  • 脑功能区胶质瘤手术策略的研究进展

    【摘要】 大脑功能区胶质瘤的手术治疗是神经外科临床工作非常棘手的问题。最大限度地切除病变、最大程度地保护功能区、避免术后神经功能缺失、提高患者术后生活质量,是脑功能区胶质瘤手术治疗的最高目标。术前功能神经影像、术中神经导航和超声、CT、MRI、肿瘤显色、电生理监测的应用,已成为当前脑功能区胶质瘤手术的重要策略。现就脑功能区手术策略的研究进行综述。

    Release date:2016-09-08 09:26 Export PDF Favorites Scan
  • Study of Functional Magnetic Resonance Imaging at Resting State for Patients in Sub-health Status

    This study sought to reveal the difference of brain functions at resting-state between subjects with sub-health and normal controls by using the functional magnetic resonance imaging (fMRI) technology. Resting-state fMRI scans were performed on 24 subjects of sub-health and on 24 healthy controls with gender, age and education matched with the sub-health persons. Compared to the healthy controls, the sub-health group showed significantly higher regional homogeneity (ReHo) in the left post-central gyrus and the right post-central gyrus. On the other hand, the sub-health group showed significantly lower ReHo in the left superior frontal gyrus, in the right anterior cingulated cortex and ventra anterior cingulate gyrus, in the left dorsolateral frontal gyrus, and in the right middle temporal gyrus. The Significant difference in ReHo suggests that thebsub-health persons have abnormalities in certain brain regions. It is proved that its specific action and meaning deserves further assessment.

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  • A Study of Resting State Functional Magnetic Resonance Imaging in Patients with Posttraumatic Stress Disorder Using Regional Homogeneity

    目的 利用局部一致性(ReHo)方法探测创伤后应激障碍(PTSD)患者在静息状态下是否存在着大脑功能异常。 方法 2010年5月-7月对18例未经治疗的地震PTSD患者和19例同样经历地震但未患PTSD的对照者进行了静息态功能磁共振成像(Rs-fMRI) 扫描。应用ReHo方法处理Rs-fMRI数据,得出PTSD患者的异常脑区,并将患者存在组间差异的脑区ReHo值与临床用PTSD诊断量表(CAPS)、汉密尔顿抑郁量表(HAMD)和汉密尔顿焦虑量表(HAMA)分别进行相关分析。 结果 ① PTSD组ReHo显著增加的脑区包括右侧颞下回、楔前叶、顶下叶、中扣带回,左侧枕中回以及左/右侧后扣带回;ReHo显著降低的脑区包括左侧海马和左/右侧腹侧前扣带回。② 异常脑区中后扣带回和右侧中扣带回ReHo与HAMD呈负相关(中扣带回r=?0.575,P=0.012;右侧后扣带回:r=?0.507,P=0.032),其余脑区ReHo与临床指标无明显相关性(P>0.05),左侧海马与CAPS的相关性相对其他脑区较大(r=?0.430,P=0.075)。 结论 PTSD患者在静息状态下即存在着局部脑功能活动的降低和增加,ReHo方法可能有助于研究PTSD患者静息状态脑活动。

    Release date:2016-09-08 09:14 Export PDF Favorites Scan
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