fMRI和DTI在脑肿瘤中的联合应用研究

功能磁共振成像可以显示脑皮质功能区的激活状态,可用于对脑肿瘤术前脑功能区的定位、预测脑肿瘤手术效果及术后评价;扩散张量成像可以观察脑白质纤维结构的特征性改变.功能磁共振成像和扩散张量成像融合技术可用于外科手术计划的制定,有助于最大限度地切除肿瘤及减少术后损害.综述功能磁共振成像和扩散张量成像融合技术在脑肿瘤中的应用.     

fMRI和DTI在脑肿瘤中的联合应用研究

功能磁共振成像可以显示脑皮质功能区的激活状态,可用于对脑肿瘤术前脑功能区的定位、预测脑肿瘤手术效果及术后评价;扩散张量成像可以观察脑白质纤维结构的特征性改变.功能磁共振成像和扩散张量成像融合技术可用于外科手术计划的制定,有助于最大限度地切除肿瘤及减少术后损害.综述功能磁共振成像和扩散张量成像融合技术在脑肿瘤中的应用.     

全脑3D-MRI在神经导航术中的应用

目的:探讨全脑3D-MRI在神经导航手术中的应用价值。方法:回顾分析30例脑肿瘤患者,根据不同的类型选择相应的MRI序列进行全脑3D-T2WI或3D-T1WI扫描,定位线上缘超出头顶,下缘包括鼻尖,然后图像在导航系统工作站进行三维重建,建立起脑部立体图像,导航定位并指导手术操作。结果:本组30例患者图像均采集成功,MRI原始图像与导航系统计算机融合后,三维立体重建效果满意,所有病例病灶均达到术前计划的实施全切(16例)或部分切除(14例),术后临床症状均有不同程度的改善,与以往类似患者的手术时间相比,呈缩短趋势。结论:全脑3D-MRI为神经外科术中导航提供了原始的影像资料,对于手术精确定位及路径选择具有重要的意义。     

磁共振功能成像在脑肿瘤中的应用研究

血氧水平依赖功能磁共振成像(BOLD—fMRI)技术的出现，为脑力科学的研究提供了新的方法，它可在脑机能活动的同时，获得解剖学、生理学及病理学信息，并具有无创性、高分辨力及不需注射对比剂的特点，因此其在脑部疾病中的研究受到人们的重视。综述了磁共振功能成像在脑瘤中的应用研究现状。     

BOLD-fMRl联合DTI在运动区脑肿瘤切除术中的应用

目的：探讨BOLD-fMRI联合DTI在运动区脑肿瘤术前定位运动功能区及皮质下纤维束中的可行性。方法：收集38例运动区脑肿瘤患者,随机分为试验组（术前联合应用BOLD-fMRI、DTI）20例和对照组（术前应用DTI）18例。2组均行运动区脑肿瘤神经导航术。使用SPSS 22.0软件分析2组手术效果及预后情况。结果：试验组肿瘤全切率（80.00%,16/20）高于对照组（50.00%,9/18）（P>0.05）;试验组术后致残率（30.00%,6/20）低于对照组（66.67%,12/18）（P<0.05）。结论：BOLD-fMRI联合DTI可帮助运动区脑肿瘤的术前功能区定位,以及设计手术入路,从而更好地保护患者的皮质下纤维束和运动功能区。     

正常人及脑肿瘤患者听觉性中英文语言刺激的fMRI研究

目的应用BOLD-MfRI研究正常人及脑肿瘤患者听觉性中英文语言皮层定位并探讨其对脑肿瘤的临床应用价值。方法应用MarconiEclipse1.5T超导型磁共振机,30例受试者,行听觉性中、英文语言刺激的BOLD-MfRI,以定位正常人和脑肿瘤患者的语言皮层。结果正常人听觉性中英文语言任务激活区域均以左侧大脑半球为主,主要有双侧颞横回、Wernicke区、Broca区和SMA区。中文语言任务刺激时脑区激活面积和程度比英文语言任务大,但英文语言任务时可见更明显的Broca区和角回激活。累及功能皮层的脑肿瘤患者患侧半球可见残留部分功能激活区,但激活区移位,分布弥散,激活程度及范围较正常人略增高。未累及功能皮层者功能区定位与正常人大致相同。结论BOLD-MfRI是一种有效而无创的功能皮层定位方法,有利于脑肿瘤的精确定位诊断并指导临床治疗。     

机器学习在脑肿瘤MRI中的发展及应用

机器学习在脑肿瘤MRI中的应用已经成为当下研究热点,其对于脑肿瘤在术前、术中、术后各期的诊断和治疗均有较大临床价值。目前,机器学习在脑肿瘤的自动分割、分类和分型的辅助诊断、术中路径的辅助分析、预后预测、数据收集等方面都取得了较大进展,但其在广泛投入临床应用前尚需克服一些限制阻碍。期望未来临床医师可以将两个领域更好地结合...     

磁共振弥散张量成像及脑功能成像在涉及运动通路脑肿瘤中的初步联合应用

目的:初步探讨联合磁共振弥散张量成像(DTI)及脑功能成像(Bold-fMRI)在涉及运动通路脑肿瘤的应用价值,观察肿瘤与功能区及邻近锥体束的关系.材料和方法:采用GE3.0TMRI成像系统,对12例临近运动皮质及锥体束的肿瘤(Ⅲ-Ⅳ级胶质瘤5例,II级胶质瘤3例,海绵状血管瘤2例,脑膜瘤2例)进行检查,均行Bold-fMRI及DTI序列,fMRI应用手的对掌运动或足背屈运动作为任务刺激.所有数据进行离线后处理,应用SPM99软件处理fMRI图像,观察运动皮质激活,DTI采用DTV1.5软件进行纤维束的成像.结果:12例肿瘤FA图显示良好,肿瘤区FA值较健侧比较有明显下降(P<0.05).纤维束重建后7例可见锥体束的消蚀破坏,其中5例伴有变形及移位;3例可见锥体束的单纯变形及受压移位;2例锥体束未见破坏及移位;11例肿瘤患侧手或足运动均可见对侧初级运动皮质(M1)的激活(1例因肢体瘫痪而失败),其中7例并有辅助运动区(SMA)及同侧M1的激活.比较fMRI及纤维束重建图发现肿瘤、功能区及白质束三者之间关系可以清楚显示.3例肿瘤DTI及fMRI联合用于外科神经导航系统,成功的指导手术.结论:DTI及Bold-fMRI联合应用可以更好的观察瘤体、功能区及白质纤维三者关系,辅助术前手术方案的制定,指导手术切除.     

磁共振功能成像在脑肿瘤中的应用研究

血氧水平依赖功能磁共振成像(BOLD-fMRI)技术的出现,为脑力科学的研究提供了新的方法,它可在脑机能活动的同时,获得解剖学、生理学及病理学信息,并具有无创性、高分辨力及不需注射对比剂的特点,因此其在脑部疾病中的研究受到人们的重视.综述了磁共振功能成像在脑瘤中的应用研究现状.     

磁敏感加权成像在脑肿瘤中的诊断应用

磁敏感加权成像（SWI）是利用物质磁敏感特性成像的新技术,对铁、钙、血红蛋白代谢物等异常敏感,已被广泛运用到中枢神经系统病变的临床诊断与研究中。脑肿瘤是神经影像学研究热点之一,对其早期诊断、分级诊断及鉴别诊断具有重要的临床意义,就SWI在脑肿瘤诊断中的应用现状予以综述。     

Combined magnetic resonance tractography and functional magnetic resonance imaging in evaluation of brain tumors involving the motor system

The goal of neuro-oncologic surgery is to maximize tumor resection while preserving vital brain functions. Identification of the relation between the tumor and adjacent functional cortical areas as well as efferent subcortical white matter tracts is important for preservation of function. Combined diffusion tensor imaging with magnetic resonance (MR) tractography and functional blood oxygen level-dependent MR imaging were applied successfully for preoperative planning and guidance in 2 patients with tumors near the motor cortex. The combination of these novel functional imaging techniques can provide new information for presurgical planning.     

In vivo visualization of myelin water in brain by magnetic resonance

We exploit the intrinsic difference in magnetic resonance spin-spin relaxation time, T₂, between water associated with myelin sheaths and water in other central nervous system tissue in order to measure myelin water content within any region of an image or to generate indirectly a myelin map of the brain. In normal volunteers, myelin water maps give the expected myelin distribution. In multiple sclerosis patients, lesions exhibit different myelin water contents providing insight into the de-myelination process unavailable from conventional magnetic resonance images. In vivo myelin measurement has important applications in the clinical management of multiple sclerosis and other white matter diseases.     

Intensity-dependent activation of the primary auditory cortex in functional magnetic resonance imaging

PURPOSE: The purpose of this study was to investigate the activation patterns of the primary auditory cortex in response to varying intensities of pure tone stimuli. METHOD: A 1,000-Hz pure tone stimulus was delivered monaurally to the right ear of 12 normal-hearing right-handed volunteers in 20-second on-off cycles. Stimuli were applied at 20 and 50 dB hearing level (HL) above threshold in 12 subjects and at 0, 20, 40, and 50 dB HL above threshold in 6 subjects. Functional magnetic resonance imaging (fMRI) data were obtained using a 1.5-T scanner and echoplanar imaging. Activated pixels were identified in the transverse temporal gyrus (TTG) of both hemispheres in response to pure tone stimuli at each intensity level using cross-correlation analysis (0.6; P < 0.0001). RESULTS: Of the 24 right and left TTGs imaged (n = 12), activation to pure tone stimuli at 20 and 50 dB HL above threshold was seen in 46% and 79% of TTGs, respectively, with bilateral hemispheric activation in 27% and 64% of subjects, respectively. The mean numbers of activated voxels were 4.0 and 13.0, respectively. Of the 12 right and left TTGs imaged at 0, 20, 40, and 50 dB HL above threshold, activation was seen in 33%, 42%, 58%, and 75% of TTGs, respectively. The mean numbers of activated voxels were 5.8, 3.2, 9.8, and 15.3, respectively. There was a nonsignificant trend toward contralateral (left) dominant TTG activation with increased tone intensity. CONCLUSION: Our results show an increased likelihood of TTG activation, increased TTG activation volume, and increased bilateral hemisphere TTG activation with increasing pure tone intensity. Our results suggest that the primary auditory cortex reflects or is directly involved in the central processing of sound intensity and that varying the intensity of even simple stimuli can alter the patterns of fMRI activation in auditory cortex.     

The effect of brain tumors on BOLD functional MR imaging activation in the adjacent motor cortex: implications for image-guided neurosurgery

BACKGROUND AND PURPOSE: Functional MR (fMR) imaging data coregistered to a neurosurgical navigation system have been proposed as guides for the resection of brain tumor in or adjacent to eloquent cortices. The purpose of this study was to compare data obtained from the side of the brain affected by tumor with the contralateral side and to determine if there are physiological limitations of fMR imaging in accurately determining the location of the primary motor cortex. METHODS: Ten patients with tumors in or directly adjacent to the motor cortex were studied with fMR imaging (finger-tapping paradigm). fMR imaging data were analyzed using multiple R values. These data were coregistered to a real-time intraoperative neurosurgical navigation system. RESULTS: Significant variability of motor cortex activation patterns was noted among individual patients. The activation volumes on the side of the tumor were significantly smaller compared with the contralateral side for all tumors not previously resected (0.66+/-0.47). This was most pronounced in glioblastomas (0.27+/-0.21). We propose that these differences were caused by a loss of autoregulation in the tumor vasculature of glioblastomas and venous effects. CONCLUSION: Notwithstanding the differences noted, the motor cortex was identified successfully in all patients. This was confirmed by intraoperative physiological identification of the motor cortex and a lack of postoperative neurologic deficit.     

颅内胶质瘤术后脑组织正常反应与肿瘤残存的MR影像学分析

目的 分析颅内胶质瘤术后脑组织反应性增强与肿瘤残存增强的影像学特点。方法回顾性分析２０４例胶质瘤术后的ＭＲＩ表现,其中男１４１例,女６３例,年龄１２－６８岁,平均３９．１岁。所有病例均在术前进行ＭＲＩ检查,并在术后１个月内至少行１次ＭＲＩ平扫及增强扫描,且均追踪至办化灶形成或肿瘤复发。使用Ｗｉｎｄｏｗｓ７．５版社会科学统计软件包（ｓｔａｔｉｓｔｉｃｓ ｐａｃｋａｇｅ ｆｏｒ ｓｏｃｉａｌ ｓｃｉｅ     

高场强术中磁共振结合语言功能神经导航技术在胶质瘤手术中的应用

目的探讨高场强术中磁共振系统与语言功能导航技术联合应用对优势大脑半球语言功能区胶质瘤手术切除效果的影响。方法收集2009年2月-2010年7月与优势大脑半球弓形束关系密切的胶质瘤患者20例,男12例,女8例,年龄20~61岁,平均43.6岁,根据术前失语评分(AQ)将患者分为语言功能正常组(n=9)和语言功能障碍组(n=11)。所有患者均接受高场强术中磁共振及弓形束导航辅助下手术,采用1.5T移动磁体、双室设计的术中磁共振系统,术前通过软件将弓形束重建的3D图像整合入神经导航系统,并在术中联合应用显微镜下功能神经导航。术前及术后2~4周、3~6个月进行随访(包括MRI检查及西方失语成套测验)。结果 20例患者均完成术前及术中弓形束重建,将3D重建图像整合入神经导航系统后成功实现了显微镜下导航。术后2~4周,语言功能正常组AQ(94.5±5.5)保持在正常水平,只有1例出现新发的传导性失语症状(AQ=81.8),而语言功能障碍组AQ(89.4±5.8)与术前比较(84.9±8.7)有明显改善(P<0.05)。术后3~6个月,语言功能正常组中除2例因肿瘤复发出现语言功能恶化外,其余患者AQ(98.3±0.5)均在正常范围,而语言功能障碍组AQ(95.2±2.6)较术后2~4周也有了明显改善(P<0.05)。两组患者术后均未出现其他新的神经功能障碍,无死亡病例。结论高场强术中磁共振结合功能神经导航是一项可靠、稳妥的技术,在肿瘤毗邻重要语言功能区及传导束时,可辅助外科手术最大限度地切除肿瘤,减轻神经功能损伤,有利于术后功能恢复。     

针刺脑功能成像的研究现状

磁共振功能成像（functional magnetic resonance imaging,fMRI）近年来被广泛用于神经外科、神经内科、药理学、精神病学以及正常人脑视觉系统、听觉系统、嗅觉系统、运动感觉系统、语言系统和记忆系统等脑功能的基础和临床研究。由于fMRI具有无创伤性、无放射性、较高的时间和空间分辨力、可准确定位脑功能区等特点,     

Restored activation of primary motor area from motor reorganization and improved motor function after brain tumor resection

BACKGROUND AND PURPOSE: Reorganization of brain function may result in preservation of motor function in patients with brain tumors. The goal of the present study was to investigate whether function of the primary motor area (M1) was restored and whether motor function improved after brain tumor resection. METHODS: Five patients with metastatic brain tumors located within or near M1 underwent awake surgery with intraoperative cortical mapping and continuous task monitoring. Preoperative and postoperative functional MR imaging (fMRI) was performed during hand clenching, and diffusion tensor imaging (DTI) was performed in 1 case to further characterize the area activated in fMRI. RESULTS: Preoperative fMRI performed during hand clenching demonstrated reorganization of motor function. In patients with severe paresis (cases 3, 4, and 5), clenching of the affected hand induced a large blood oxygen level-dependent response in the right hemisphere, mainly in the anterior temporal lobe, despite the location site of the tumor. Postoperative fMRI during hand clenching demonstrated activation of the contralateral M1. Furthermore, in case 5, DTI detected tracts, possibly the inferior longitudinal fasciculus, arising from anterior temporal activated area as well as tracts connecting the premotor and M1 activated area. This patient demonstrated mirror movement of the hand during the course of motor function recovery. CONCLUSIONS: Tumor resection resulted in restoration of M1 function and improved motor function in patients with preoperative reorganization of M1 function. Furthermore, the preoperative reorganization of motor function in cases with severe paresis may be related to changes in the right hemisphere, including the temporal lobe.     

Combining functional and structural brain magnetic resonance imaging in Huntington disease

OBJECTIVE: To concurrently investigate with magnetic resonance (MR) the brain activation and regional brain atrophy in patients with Huntington disease (HD). METHODS: Nine symptomatic HD patients and 11 healthy subjects underwent an MR study including functional MR acquisition during finger tapping of the right hand and high-resolution T1-weighted images. Functional and structural data were analyzed using Statistical Parametric Mapping 2 software. RESULTS: As compared with control subjects, HD patients showed decreased activation in the left caudate nucleus and medial frontal and anterior cingulate gyri and increased activation in the right supplementary motor area and supramarginal gyrus and left intraparietal sulcus. The pattern of atrophy included thinning of the gray matter (GM) in the insula, inferior frontal gyrus, caudate, lentiform nucleus, and thalamus, bilaterally, in the left middle frontal, middle occipital, and middle temporal gyri, and of periventricular, subinsular, right temporal lobe, and left internal capsule white matter. Only the decreased activation in the caudate nucleus correlated topographically with the caudate GM loss. CONCLUSION: The cortical areas of functional changes do not correspond to those of GM atrophy in patients with HD and are likely to reflect decreased output of the motor basal ganglia-thalamo-cortical circuit and compensatory recruitment of accessory motor pathways.