基于导航的立体定向脑电图在癫痫外科中的应用

目的 通过综合应用神经导航结合脑立体定向技术获取患者三维立体脑电图以精确定位颅内致痫灶指导外科手术治疗,观察在难治性癫痫患者治疗中的安全性、有效性。方法 我科收治的14例药物难治性癫痫患者行颅脑三维磁共振及头颅静脉成像,利用Brain-LAB神经导航系统融合影像数据,建立立体大脑及皮层静脉模型,设计路径避开皮层血管,导航生成靶点坐标,然后在Leksell立体定向下植入立体定向电极,分析其安全性及有效性。结果 14例患者共植入94枚电极,所有电极均成功植入,主要并发症是一例电极植入位置偏移及该电极导致的颅内少量出血及一例间接颅内感染,术后进行视频脑电监测,确定颅内致痫灶并进行手术(一例患者脑深部电刺激治疗),术后随访疗效满意。结论 建立立体大脑及皮层静脉模型有效避免电极植入出血;立体定向电极植入作为侵袭性评估致痫灶的方法是安全、有效的,并在行硬膜下皮层电极植入术后效果不佳的病例中体现优越性。     

颅内电极在功能区癫痫治疗中的应用

目的 探讨颅内电极在功能区癫痫治疗中致痫灶定位及功能区定位中的作用.方法 回顾性分析经我科治疗的涉及功能区的癫痫患者34例,经颅内电极植入明确致痫灶后,均行皮层电刺激定位功能区,根据致痫灶与功能区关系图决定治疗方案.结果 致痫灶与中央前后回相邻者10例,术中行单纯致痫灶切除术;与中央前后回部分重叠者14例,术中行非功能区致痫灶切除,功能区致痫灶皮层电凝热灼术;完全位于中央前后回皮层区域内者5例,术中行单纯皮层电凝热灼术.术后癫痫发作较术前明显减少,无明显术后功能缺失.结论 颅内电极植入是定位功能区癫痫致痫灶及功能区的有效方法.     

脑功能区病变术前运动功能的评估

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。     

影像融合及颅内电极三维重建在癫痫术前计划中的应用

目的 探讨影像融合及颅内电极三维重建在癫痫术前计划中的应用价值。方法 对于行开颅颅内电极植入术以进行慢性皮层脑电评估的癫痫患者,获取其术前MRI及电极植入术后CT的影像资料,利用SynergyCranial软件将两种影像进行融合,并对颅内电极、脑表面及颅骨进行三维重建,以显示出颅内电极与骨窗、脑表面的相对位置,为致痫灶的定位及下一步手术计划的制定提供准确的解剖信息。结果 在2015年4月至8月共对10例需慢性皮层脑电监测的癫痫患者进行了开颅颅内电极植入术。通过术前MRI与电极植入术后CT影像融合技术,可以在MRI断层图像上观察到皮层电极中各触点与脑沟、脑回的相对平面位置,克服了术后无法行MRI检查的弊端。通过对影像融合后的颅内电极、脑表面及颅骨进行三维模型重建,可以立体直观地观察到颅内电极与脑表面和骨窗的相对空间位置,电极触点的重建成功率达90%。根据重建出的三维融合影像,结合皮层脑电图的监测结果,划定出致痫灶的位置与范围,制定手术计划,进行致痫灶切除术,术后所有患者均取得了良好效果。结论 在对行颅内电极监测的癫痫患者制定手术计划时,利用影像融合和颅内电极三维重建技术,可以获得更为准确且直观的致痫灶定位信息,有利于提高致痫灶切除术的准确性和安全性。     

外伤后癫痫的外科治疗(附14例报告)

目的 探讨外伤后癫痫的手术治疗方法和效果. 方法 回顾性分析北京军区总医院附属八一脑科医院自2010年11月至2013年7月接受外科手术治疗的14例难治性外伤后癫痫患者临床资料.所有患者均经严格的术前评估,其中5例病灶毗邻重要功能区者分别采用颅内电极植入(4例)和术中神经功能导航(5例);随后分别行皮层电刺激和功能磁共振导航完成脑功能区精确定位及致痫灶与运动区的位置关系确定.手术切除所有患者癫痫病灶,术后定期进行随访并采用Engle分级进行疗效评定. 结果 所有患者均成功实施了癫痫病灶切除术.颅内电极植入的患者经功能磁共振导航和皮层电刺激双重定位,毗邻功能区的癫痫病灶达到精准切除,同时患者运动功能得到良好保护.术后随访12～30个月,Engle Ⅰ级7例、Ⅱ级5例、Ⅲ级2例,未出现永久性神经功能障碍. 结论 对于药物难治性外伤后癫痫,精确定位癫痫病灶和脑功能区后可以经外科切除术获得良好疗效.     

颅内埋藏电极及皮层电刺激在脑中央区致痫灶切除术中的联合应用(附7例报告)

目的 探讨颅内埋藏电极和皮层电刺激技术在脑中央区致痫灶切除术中的作用.方法 对7例术前怀疑致痫灶临近或累及大脑中央区的癫痫患者,将颅内电极置于硬膜下或皮层表面,行长程皮层脑电图(ECoG)监测及皮层电刺激,确定致痫灶和大脑中央区范围及二者位置关系.术中在保护中央区的前提下,最大限度切除致痫灶.术后随访6～12个月,根据Engel's术后效果分级和Karnofsky生活状态量表(KPS)评分进行评估.结果 :7例患者术后均无癫痫发作,达到Engel's I级,KPS评分结果较术前提高.结论 :颅内埋藏电极及皮层电刺激联合应用,可指导脑中央区致痫灶的手术,在切除致痫灶的同时保护脑中央区,达到既控制癫痫发作又无术后严重功能障碍的目的 ,可显著提高患者生活质量.     

功能磁共振与皮层电刺激定位感觉运动区的比较

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.     

清华大学玉泉医院第六届癫痫外科术前评估学习班通知

由清华大学玉泉医院癫痈中心举办的第六届癫痈外科术前评估学习班定于2014年4月9日一13日在北京清华大学近春园举行。学习班就癫痈外科术前评估进行全面系统的讲解,包括术前评估的流程,致痈灶定位及手术方案的确定,各种癫痛外科手术技巧,头皮视频脑电图监测技术,颅内电极植入（硬膜下电极及立体定向深部电极）方法,颅内脑电图正常及异常脑波分析,颅内脑电图发作起源的特点,皮层电刺激、诱发电位、颅内高频脑电分析等技术定位脑功能区,另外包括大量的典型病例讨论及发作视频症状学分析。     

清华大学玉泉医院第六届癫痫外科术前评估学习班通知

由清华大学玉泉医院癫痫中心举办的第六届癫痫外科术前评估学习班定于2014年4月9日～13日在北京清华大学近春园举行。学习班就癫痫外科术前评估进行全面系统的讲解,包括术前评估的流程,致痫灶定位及手术方案的确定,各种癫痫外科手术技巧,头皮视频脑电图监测技术,颅内电极植入（硬膜下电极及立体定向深部电极）方法,颅内脑电图正常及异常脑波分析,颅内脑电图发作起源的特点,皮层电刺激、诱发电位、颅内高频脑电分析等技术定位脑功能区,另外包括大量的典型病例讨论及发作视频症状学分析。     

两种感兴趣区选择方法示踪锥体束在中央区病变手术中的初步对照研究

目的采用术中直接皮层下电刺激技术(Ds CS),验证并对比以功能磁共振运动激活区为感兴趣区示踪(f MRI guided DTI-FT)的锥体束和以传统解剖初级运动皮层为感兴趣区进行示踪的锥体束。方法前瞻性研究12例涉及中央区的病灶患者,以f MRI运动激活区、大脑脚为感兴趣区的改进方法和以中央前回、大脑脚为感兴趣区的传统方法分别示踪锥体束,神经导航辅助下引导手术,术中记录同一电刺激阳性点与两种方法成像锥体束之间的距离,比较两种方法成像锥体束与Ds CS的符合率。结果除1例患者因运动功能障碍致f MRI激活失败,1例电刺激结果阴性,余患者均成功显示两种方法重建的锥体束,并应用于术中神经导航定位和辅助切除病灶。两种方法成像锥体束与Ds CS的符合率分别为77%和70%,16个Ds CS阳性位点距离两种方法成像的锥体束之间的平均最短距离分别为(4.3±2.8)mm和(5.5±3.4)mm,对比差异结果均有统计学意义(χ2=7.393,t=0.675,P0.05)。术后5例上肢暂时性偏瘫,1例上下肢暂时性偏瘫,余6例患者手术前后肌力无改变,术后2周4例肢体运动同术前或较术前好转,余2例仍有偏瘫。结论以功能磁共振运动激活区为感兴趣区示踪锥体束的方法在涉及中央区的手术中可同时保护功能皮层和锥体束,有助于妥善处理病灶并有效保护脑功能区。     

年轻人与老年人简单乘法运算之功能磁共振成像研究

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。     

Anodal vs cathodal stimulation of motor cortex: a modeling study.

OBJECTIVE: To explore the effects of electrical stimulation performed by an anode, a cathode or a bipole positioned over the motor cortex for chronic pain management. METHODS: A realistic 3D volume conductor model of the human precentral gyrus (motor cortex) was used to calculate the stimulus-induced electrical field. The subsequent response of neural elements in the precentral gyrus and in the anterior wall and lip of the central sulcus was simulated using compartmental neuron models including the axon, soma and dendritic trunk. RESULTS: While neural elements perpendicular to the electrode surface are preferentially excited by anodal stimulation, cathodal stimulation excites those with a direction component parallel to its surface. When stimulating bipolarly, the excitation of neural elements parallel to the bipole axis is additionally facilitated. The polarity of the contact over the precentral gyrus determines the predominant response. Inclusion of the soma-dendritic model generally reduces the excitation threshold as compared to simple axon model. CONCLUSIONS: Electrode polarity and electrode position over the precentral gyrus and central sulcus have a large and distinct influence on the response of cortical neural elements to stimuli. SIGNIFICANCE: Modeling studies like this can help to identify the effects of electrical stimulation on cortical neural tissue, elucidate mechanisms of action and ultimately to optimize the therapy.     

Functional Plasticity of the Motor Cortical Structures Demonstrated by Navigated TMS in Two Patients with Epilepsy

BackgroundRecently, navigated transcranial magnetic stimulation (nTMS) has been suggested to be useful in preoperative functional localization of motor cortex in patients having tumors close to the somatomotor cortex. Resection of tumors in anatomically predicted eloquent areas without adverse effects have emphasized functional plasticity elicited by intracranial pathology.ObjectiveTo describe functional plasticity of motor cortex indicated by nTMS in two patients with epilepsy.MethodsnTMS, functional MRI (fMRI), diffusion-tensor (DT)-tractography and magnetoencephalography (MEG) were utilized to preoperatively localize motor cortical areas in the workup for epilepsy surgery. The localizations were compared with each other, with the cortical anatomical landmarks, and in one patient with invasive electrical cortical stimulation (ECS).ResultsIn two out of 19 studied patients, nTMS identified motor cortical sites that differed from those indicated by anatomical landmarks. In one patient, nTMS activated preferentially premotor cortex rather than pathways originating from the precentral gyrus. MEG and fMRI localizations conformed with nTMS whereas ECS localized finger motor function into the precentral gyrus. Resection of the area producing motor responses in biphasic nTMS did not produce a motor deficit. In the other patient, nTMS indicated abnormal ipsilateral hand motor cortex localization and confirmed the functionality of aberrant motor cortical representations of the left foot also indicated by fMRI and DT-tractography.ConclusionnTMS may reveal the functional plasticity and shifts of motor cortical function. Epileptic foci may modify cortical inhibition and the nTMS results. Therefore, in some patients with epilepsy, the nTMS results need to be interpreted with caution with regard to surgical planning.     

基于ReHo方法的精神分裂症患者攻击行为的静息态fMRI研究

目的 通过相关脑区结构与功能的对照研究,探讨精神分裂症患者暴力攻击行为的神经认知障碍基础.方法 对有、无攻击行为的精神分裂症患者和健康对照三组人群各21例进行静息状态下脑功能性磁共振成像（fMRI）,运用局域一致性（ReHo）分析方法进行数据分析处理,比较三组之间的差异.结果 与健康对照组相比,精神分裂症非攻击组在左侧额叶、中央前回、中央后回、两侧丘脑、右侧脑岛等脑区的局部一致性存在异常;而精神分裂症攻击组除表现上述脑区局部一致性异常,还表现出两侧前扣带回、左侧海马旁回等边缘系统脑区局部一致性的异常.结论 额叶、丘脑、中央前回、中央后回及脑岛等脑区的异常可能与精神分裂症症状以及攻击行为均有关,而边缘系统等脑区的异常可能与精神分裂症的攻击行为存在特异性联系.     

精神分裂症首次发病未治疗患者静息态下局部脑区自发活动的研究

目的探讨精神分裂症首次发病未治疗患者静息态下局部脑区自发活动的情况:方法:利用低频振幅(ALFF)方法,对27例首次发病未治疗的精神分裂症患者(患者组)进行静息状态下功能磁共振(fMRI)扫描,对影像学数据进行ALFF方法处理,结果与22名年龄、性别及受教育程度相匹配的健康对照者(正常对照组)比较。结果:与正常对照组相比,患者组ALFF显著增高的脑区是运动前区、辅助运动区和眶额回;ALFF显著降低的脑区是楔前叶、后扣带回、内侧前额叶和角回(P0.05,Alphaism矫正)。结论:精神分裂症首次发病未治疗患者在静息态下运动前区、辅助运动区、眶额回、楔前叶、后扣带回、内侧前额叶和角回的局部脑区自发活动异常,这些异常脑区可能有助于解释精神分裂症的病理机制。     

Functional MRI for presurgical planning: problems, artefacts, and solution strategies

OBJECTIVES: Presurgical mapping of motor function is a widely used clinical application of functional (f) MRI, employing the blood oxygenation level dependent contrast. The aim of this study was to report on 3 years experience of 194 fMRI studies on the representation of motor function in 103 patients and to describe the problems and artefacts that were typically present. METHODS: An evaluation was carried out to determine whether the patients' age, type or location of the tumourous lesion, severity of the paresis, or the tasks used during the investigation have an effect on artefacts of fMRI studies and how these artefacts are best overcome. RESULTS: Functional MRI identified the motor regions in 85% of all investigated paradigms. In 11% of the investigated patients no information at all on functional localisation was obtained. A draining vein within the central sulcus was present in all patients that showed activation within the parenchyma of the precentral gyrus but also in three patients in whom no parenchymal activation was present. Head movement artefacts were the most frequent cause for fMRI failure, followed by low signal to noise ratio. Motion artefacts were correlated with the degree of paresis and with the functional task. Tasks involving more proximal muscles led to significantly more motion artefacts when compared with tasks that primarily involved distal muscles. Mean MR signal change during task performance was 2.5%. CONCLUSIONS: Most of the artefacts of functional MRI can be reliably detected and at least in part be reduced or eliminated with the help of mathematical algorithms, appropriate pulse sequences and tasks, and-probably most important-by evaluating the fMRI raw data-that is, the MR signal time courses.     

汉-英双语言脑功能区外科手术定位的探讨

目的探讨中国人汉-英语的脑功能区定位及手术方法。方法对1例广东籍汉语普通话-英语双语言脑功能区低级别胶质瘤病人，术前通过汉、英语语义、语音和图文实验任务，经功能磁共振（fMRI）定位汉语和英语皮质区．由神经功能导航制定手术计划和定位，术中采用超声探测肿瘤，全麻唤醒下双语定位监测功能区，行显微手术切除病变。结果fMRI检出汉语激活区在肿瘤的前下外部，即额中下回后部，英语激活区则位于近肿瘤的额上中回后部。切除肿瘤过程中英语较汉语出现明显障碍征象。肿瘤获次全切除，术后出现短暂辅助运动区（SMA）综合征，英语运动性失语于术后1周内恢复；术后3个月，fMRI显示英语激活区重塑位移。术后8个月随访，病人恢复正常生活和工作，术前癫痫症状消失。结论①采用双语方式进行fMRI扫描定位、神经导航功能区定位和术中清醒状态下双语监测，使双语言脑功能区病变病人的手术治疗成为可能。②在保留母语功能的前提下，对第2语言区病变做到最大限度切除后，其语言功能仍可能得到恢复。     

The pyramidal tract in congenital hemiparesis: relationship between morphology and function in periventricular lesions

Three-dimensional MRI data sets were obtained from 12 young adult patients with congenital spastic hemiparesis caused by unilateral periventricular white matter lesions. The impact of these lesions on corticospinal projections to the upper and lower extremities was assessed on reconstructed semi-coronal planes following anatomical landmarks of somatotopic organization in the precentral gyrus and in the internal capsule: a more anterior plane running through the hand-knob of the precentral gyrus and the anterior portion of the posterior limb of the internal capsule representing projections to the upper extremity, and a more posterior plane running through the top of the precentral gyrus and the middle portion of the posterior limb of the internal capsule representing projections to the lower extremity. In addition, the total lesion extent was determined volumetrically, and Wallerian degeneration was assessed qualitatively in the internal capsule and quantitatively by measuring brainstem asymmetry. We found a strong correlation between motor dysfunction of the upper and lower limb and the lateral extent of the periventricular lesion measured on the respective semi-coronal planes. The total lesion volume and the degree of Wallerian degeneration correlated less strongly, both reaching statistical significance only with motor impairment of the hand.     

Motor cortex localization using functional MRI and transcranial magnetic stimulation.

OBJECTIVE: Congenital brain lesions producing focal seizures may be accompanied by reorganization of the areas responsible for motor and sensory functions within the brain due to a phenomenon that has been termed "neuronal plasticity." This can be studied using functional MRI (fMRI) and transcranial magnetic stimulation (TMS). Using either method, the motor cortex can be localized noninvasively, but to date there have been few studies correlating the level of agreement between the two techniques. METHODS: We used fMRI and TMS to localize the motor cortex in a young woman with intractable focal seizures, congenital left arm weakness, and a dysplastic right hemisphere on MRI. RESULTS: There was excellent agreement in the localization of motor representation for each hand. Both were predominantly located in the left hemisphere. fMRI also showed an area of posterior activation in the right hemisphere, but there was no evidence of descending corticospinal projections from this site using TMS, direct cortical stimulation, and Wada testing. CONCLUSIONS: Functional MRI (fMRI) and transcranial magnetic stimulation (TMS) were successfully used to localize cortical motor function before epilepsy surgery. Each technique demonstrated migration of motor function for the left hand to the left motor cortex. After resection of the dysplastic right precentral gyrus there was no permanent increase in weakness or disability. The two techniques are complementary; fMRI indicates all cortical areas activated by the motor task, whereas TMS identifies only those areas giving rise to corticospinal projections.     

Interhemispheric visuo-motor integration in humans: the effect of redundant targets

We used event-related functional magnetic resonance imaging (fMRI) to investigate the functional locus of response facilitation during parallel visuo-motor processing. In a simple reaction-time task, subjects typically respond faster to two copies of the same stimulus than to a single copy. This facilitation, called the redundant-target effect, can occur at three functional levels: perceptual, 'cognitive' or motor. Normal right handers were studied while performing a simple reaction-time task to unilateral (left or right) and bilateral light flashes. Subjects were instructed to respond with their right index finger. Reaction times were faster to bilateral light flashes than to unilateral ones, even right flashes. Greater fMRI signal for bilateral stimuli compared to unilateral ones was observed in the left precentral and postcentral gyrus, and in the right precentral gyrus. A greater fMRI signal for bilateral and for unilateral left stimuli, compared to unilateral right stimuli, was observed in an area of the right intraparietal sulcus. These results support the hypothesis that the functional locus of response facilitation during parallel visuo-motor processing is premotor.