颅内电极监测癫痫发作初始期脑电定位意义

目的 探讨颅内电极监测癫痫发作初始期脑电对致痫灶的定位价值。方法 14例难治性癫痫患，其临床，影像学检查及头皮脑电记录等不能精确定位致痫灶，经颅骨钻孔，埋置颅内深部和／或皮层电极，长程脑电监测并分析发作初始期脑电的异常放电节律和范围，对比术后病理学检查和随访结果，分析发作初期脑电定位致痫灶的准确性。结果 记录到47次临床发作。发作初期异常放电可分为4种形式；低幅愉节律，尖波节律，高幅棘波节律和棘慢波节律。按异常放电范围可分为：局限性放电，区域性放电和广泛性放电，11例（78．5％），患准确定位了致痫灶，术后癫痫发作消失（64．3％）或极少发作（14．2％），2例（14．2％）发作减少90％以上，1例（7．1％）术后无改善。结论 颅内埋置电极脑电监测癫痫发作初始期异常放电形式，部位和异常放电范围是定位致痫灶可靠的方法。     

颅内电极埋置定位切除痫灶的护理体会

目的：探讨颅内电极埋置定位切除痫灶的护理效果。方法：回顾性分析25例通过对颅内电极埋置获取切除痫灶定位信息,然后实施癫痫手术的临床资料。结果：通过系统的护理,25例中除3例并发脑脊液漏延长住院10~15 d外,其余22例全部顺利康复按预定日期出院。术后随访6个月~1年,总有效率为95.2%,优良率为83.0%。结论：颅内电极埋置能明显提高致痫灶定位的准确性,但手术后为正确捕获痫灶需要停用抗癫痫药物,癫痫发作频率增加,术后的护理配合尤为重要。     

发作间期蝶骨电极在颞叶癫痫诊断中的作用26例分析

目的应用蝶骨电极定位颞叶癫痫的致痫灶。方法对颞叶癫痫的患者,在记录头皮脑电同时,穿刺蝶骨电极记录脑电26例。结果 （1）26例患者都能记录到蝶骨电极的痫样放电;（2）88.5%蝶骨电极所显示的痫样放电能同时被头皮脑电识别出;（3）26例患者无因蝶骨电极引发的并发症。结论蝶骨电极可以记录到头皮脑电无法记录到的痫样放电,结合其他方法可对颞叶癫痫的致痫灶定位。     

皮质电极监测在致痫性蛛网膜囊肿手术中的应用

目的探讨术中皮质电极监测在致痫性蛛网膜囊肿手术治疗中的应用价值。方法蛛网膜囊肿病人19例,术前均有癫痫发作史,CT或MRI检查确诊。术前常规脑电图检查正常3例,轻度异常8例,中度异常6例,重度异常2例。常规开颅行蛛网膜囊壁全部或部分切除,同时行皮质电极监测,根据癫痫波位置行致痫灶切除或软膜下横切术。结果 19例病人术中皮质电极均监测到癫痫波,其中12例行致痫灶切除术,4例行多处软膜下横切术,3例行多处软膜下横切并颞极、海马切除术。术后常规脑电图检查均未见癫痫波。随访6个月～4年,18例癫痫消失;1例发作明显减少,口服药物可控制。结论在致痫性蛛网膜囊肿病人手术中,使用皮质电极监测致痫灶,定位准确,灵敏度高。     

动态脑电活动监测对儿童发作性脑疾病的评估

背景:24 h动态脑电图是在常规脑电图基础上延长描记时间,以便对各个状态下的脑电活动进行监测,从而大大提高了癫痫患儿的检出率.目的:通过对癫痫和可疑癫痫患者进行24 h动态脑电图监测,探讨其对儿童发作性脑疾病的评估价值.设计:病例分析.单位:江西医学院第二附属医院神经内科.对象:选择2001-07/2004-10江西医学院第二附属医院神经内科住院及门诊的发作性脑疾病患儿151例,其中男99例,女52例,年龄3个月～14岁.根据临床诊断分为两组:癫痫组85例,可疑癫痫组66例.151例患儿中有39例曾行脑电图检查,21例行CT检查,3例行MRI检查.方法:对参加者详细询问病史、神经科查体,进行24 h动态脑电图监测(凡在监测期间出现棘波、尖波、棘(尖)慢综合波、爆发性高幅慢波、高度失律波、新生儿单一节律爆发波者,以及过度换气早期突破或局限性爆发性慢波者均为痫样放电;背景波异常,儿童期枕部阵发性慢波,睡眠期极度纺缍波及新生儿散发性一过性尖波,偶见不典型尖-慢波综合均属非特异性异常),并收集常规脑电图、CT或MRI检查结果.主要观察指标:①观察24 h动态脑电图对儿童发作性疾病的异常率、痫样放电率.②痫样放电时间、部位、临床发作与异常发作的关系.③将24 h动态脑电图对儿童发作性疾病的异常率、痫样放电率与常规脑电图、CT或MRI结果进行对比分析.结果:151例患儿均进入结果分析.①151例患儿动态脑电图监测结果异常122例,其中痫样放电97例.癫痫组痫样放电率明显高于可疑癫痫组[79%(67/85),45%(30/66),(x2=18.008,P＜0.005)].②癫痫组中动态脑电图痫性放电以一侧半球或局限性一侧偏胜以及双侧大脑半球为主,可疑癫痫组中以双侧大脑半球痫样放电出现率最高.③痫样放电时间以睡眠时期为主,占74%(72/97),其中68%(44/97)见于浅睡期.④癫痫组临床发作14例,痫样放电出现率93%(13/14),明显高于可疑癫痫组[临床发作25例,痫样放电出现率12%(12/25),(x2=6.741,P＜0.01)].⑤151例患儿中有39例曾行常规脑电图检查,其中非特异性异常19例,痫样放电7例;动态脑电图中非特异性异常5例,痫样放电29例,两组患儿的常规脑电图以非特异性异常为主,动态脑电图以痫样放电为主.结论:24 h动态脑电图用于诊断儿童发作性脑疾病的痫样放电率明显增高,并能确定放电部位及时间,充分体现了动态脑电图对儿童发作性脑疾病评估的优越性.     

动态脑电活动监测对儿童发作性脑疾病的评估(英文)

背景:24h动态脑电图是在常规脑电图基础上延长描记时间,以便对各个状态下的脑电活动进行监测,从而大大提高了癫痫患儿的检出率。目的:通过对癫痫和可疑癫痫患者进行24h动态脑电图监测,探讨其对儿童发作性脑疾病的评估价值。设计:病例分析。单位:江西医学院第二附属医院神经内科。对象:选择2001-07/2004-10江西医学院第二附属医院神经内科住院及门诊的发作性脑疾病患儿151例,其中男99例,女52例,年龄3个月～14岁。根据临床诊断分为两组:癫痫组85例,可疑癫痫组66例。151例患儿中有39例曾行脑电图检查,21例行CT检查,3例行MRI检查。方法:对参加者详细询问病史、神经科查体,进行24h动态脑电图监测(凡在监测期间出现棘波、尖波、棘(尖)慢综合波、爆发性高幅慢波、高度失律波、新生儿单一节律爆发波者,以及过度换气早期突破或局限性爆发性慢波者均为痫样放电;背景波异常,儿童期枕部阵发性慢波,睡眠期极度纺缍波及新生儿散发性一过性尖波,偶见不典型尖-慢波综合均属非特异性异常),并收集常规脑电图、CT或MRI检查结果。主要观察指标:①观察24h动态脑电图对儿童发作性疾病的异常率、痫样放电率。②痫样放电时间、部位、临床发作与异常发作的关系。③将24h动态脑电图对儿童发作性疾病的异常率、痫样放电率与常规脑电图、CT或MRI结果进行对比分析。结果:151例患儿均进入结果分析。①151例患儿动态脑电图监测结果异常122例,其中痫样放电97例。癫痫组痫样放电率明显高于可疑癫痫组犤79%(67/85),45%(30/66),(χ2=18.008,P<0.005)犦。②癫痫组中动态脑电图痫性放电以一侧半球或局限性一侧偏胜以及双侧大脑半球为主,可疑癫痫组中以双侧大脑半球痫样放电出现率最高。③痫样放电时间以睡眠时期为主,占74%(72/97),其中68%(44/97)见于浅睡期。④癫痫组临床发作14例,痫样放电出现率93%(13/14),明显高于可疑癫痫组犤临床发作25例,痫样放电出现率12%(12/25),(χ2=6.741,P<0.01)犦。⑤151例患儿中有39例曾行常规脑电图检查,其中非特异性异常19例,痫样放电7例;动态脑电图中非特异性异常5例,痫样放电29例,两组患儿的常规脑电图以非特异性异常为主,动态脑电图以痫样放电为主。结论:24h动态脑电图用于诊断儿童发作性脑疾病的痫样放电率明显增高,并能确定放电部位及时间,充分体现了动态脑电图对儿童发作性脑疾病评估的优越性。     

皮层脑电图监测切除伴发癫痫的颅内病变

目的:探讨皮层脑电图(CEEG)监测下切除伴癫痫症状的颅内病变手术效果。方法:23例患者,其中胶质瘤9例,动静脉畸形2例,脑膜瘤6例,蛛网膜囊肿6例。术中行CEEG监测,先切除病变再行CEEG监测,如仍有棘慢波则提示仍存在痫灶,时非功能区则予以切除,对功能区则用低功率电灼该处皮层,直至棘波和慢波消失。结果:23例患者切除病变前均可通过CEEG捕捉到痫波,病变及痫灶完全切除或热灼后,术后常规脑电图检查全部病例均未发现癫痫波。出院后随访12～23个月,22例痊愈,1例尚有部分性发作,但发作频率明显减少,间隔时间延长,口服抗癫痫药可控制。结论:术中CEEG监测可明确致痫灶位置,对提高手术疗效有一定价值。     

癫痫病人颅内电极埋置术后视频脑电监测期的护理

近年来，难治性癫痫的外科治疗引起了学术界的广泛关注，而癫痫灶定位是手术成功的关键步骤，通过现有的无创方法不能定位者需要应用颅内电极埋置进行长程视频脑电监测(V-EEG)，这一技术被认为是目前定位癫痫灶的最佳方法。本文总结了2001年4月-2003年4月期间我科接受颅内电极埋置术的38例难治性癫痫病人资料。现将有关护理体会报告如下。     

脑电监测中癫痫发作的护理

目的 :为癫痫患者提供在脑电监测癫痫发作过程的安全护理 ,保证脑电监测质量 ,确定致痫灶 ,为手术提供准确定位。方法 :脑电监测前对患者进行心理评估 ,对患者应用抗癫痫药物进行干预 ,做好脑电监测过程中癫痫发作时各种抢救工作及护理安全措施。结果 :4 8例癫痫患者脑电监测癫痫发作、美解眠诱发癫痫发作 ,抢救工作准备充分 ,护理措施得当 ,监测医生和护士密切配合 ,既描记到致痫灶波形 ,又安全度过癫痫发作过程 ,无一例意外发生。结论 :脑电监测癫痫波形是确定致痫灶一种主要检查项目 ,是为选择手术方式提供科学依据的一种主要手段。在脑电监测患者癫痫发作期间 ,监测医生与护士进行密切配合 ,做好各项抢救及护理措施准备 ,是患者平安度过脑电监测癫痫发作期的重要保证。     

癫痫手术术中皮层脑电监测的护理

目的 总结术中皮层脑电监测的护理经验.方法 术中使用皮层电极对病灶及相应部位皮层脑电监测,确定癫痫灶的位置及范围,显微镜下行癫痫灶切除,切除后再次进行皮层脑电图监测.结果 本组34例在监测中均有痫样放电,患者术后8～12 d恢复顺利,无并发症.结论 术中皮层脑电监测对癫痫的手术治疗十分重要,对于术前定位的病例,可进一步...     

Ictal localization by source analysis of infraslow activity in DC-coupled scalp EEG recordings

New bedside long-term DC-coupled EEG techniques have demonstrated that infraslow (<0.5 Hz) activity lateralizes temporal lobe seizures (Vanhatalo, S., Holmes, M.D., Tallgren, P., Voipio, J., Kaila, K., Miller, J.W., 2003a. Very slow EEG responses indicate the laterality of temporal lobe seizures: a DC-EEG study. Neurology 60, 1098-1104). However, even high amplitude infraslow activity is difficult to localize by simple visual inspection if there is overlying faster EEG activity or slow artifact. In this study, we address this with improved DC-coupled EEG recording and analysis techniques and also extend observation to both temporal and extratemporal seizures. Recordings were performed during presurgical evaluation of medically intractable epilepsy, with 20 seizures in 11 patients analyzed. A commercial DC-coupled recording device was used, with sintered Ag/AgCl electrodes in a standard 10-10 system array, with additional anterior temporal and subtemporal electrodes. Seizures were localized with a software package by means of source montage analysis. Infraslow signals occurred with all seizures, often with amplitude orders of magnitude higher than conventional frequencies (0.5 to 70 Hz). The most reliable method to localize these signals and distinguish them from artifacts used a source montage after low-pass filtering below 0.5 Hz. Five of the eight patients who received epilepsy surgery had follow-up documenting significant seizure reduction, and infraslow signal analysis correctly localized the region of seizure onset in all five, while conventional noninvasive EEG recording and analysis localized only three of the five. Several seizures were also analyzed using principle component analysis source localization methods, with the results less consistently localizing than source montage analysis. DC-coupled EEG recordings give clinically useful information to noninvasively localize the seizure focus. The value of this method is increased by source analysis tools that reveal localized changes more clearly than direct visual inspection.     

癫痫患者的视频脑电图研究

目的 癫痫诊断主要依据患发作时的临床表现及脑电图检查。由于各种原因，部分患不能回忆、描述发作时的情况，可能造成诊断错误。视频脑电图可以提高诊断的正确性。本研究的目的是评价视频脑电图在癫痫诊断中的作用。方法 对5例癫痫患进行了视频脑电图记录。参考导联法记录，A1 A2为参考电极，Cz接地，闭目。结果 5例患记录过程中均出现临床发作，发作次数分别为4、2、1、1、1次。发作前、中、后时的脑电图变化与惟床表现之间存在一定的联系。结论 视频脑电图可以弥补常规脑电图的不足，提高癫痫诊断的准确性。     

Canonical decomposition of ictal scalp EEG reliably detects the seizure onset zone

Long-term electroencephalographic (EEG) recordings are important in the presurgical evaluation of refractory partial epilepsy for the delineation of the irritative and ictal onset zones. In this paper we introduce a new algorithm for an automatic, fast and objective localizing of the ictal onset zone in ictal EEG recordings. We extracted the potential distribution of the ictal activity from EEG using the higher order canonical decomposition method, also referred to as the CP model. The CP model decomposes in a unique way a higher order tensor in a minimal sum of rank-1 'atoms'. We showed that only one atom is related to the seizure activity. Simulation experiments demonstrated that the method correctly extracted the potential distribution of the ictal activity even with low signal-to-noise ratios. In 37 ictal EEGs, the CP method correctly localized the seizure onset zone in 34 (92%) and visual assessment in 21 cases (57%) (p=0.00024). The CP method is a fast method to delineate the ictal onset zone in ictal EEGs and is more sensitive than visual interpretation of the ictal EEGs.     

Accurate epileptogenic focus localization through time-variant functional connectivity analysis of intracranial electroencephalographic signals

Epilepsy is a neurological disorder characterized by seizures, i.e. abnormal synchronous activity of neurons in the brain. During a focal seizure, the abnormal synchronous activity starts in a specific brain region and rapidly propagates to neighboring regions. Intracranial ElectroEncephaloGraphy (IEEG) is the recording of brain activity at a high temporal resolution through electrodes placed within different brain regions. Intracranial electrodes are used to access structures deep within the brain and to reveal brain activity that cannot be observed with scalp EEG recordings. In order to identify the pattern of propagation across brain areas, a connectivity measure named the Adapted Directed Transfer Function (ADTF) has been developed. This measure reveals connections between different regions by exploiting statistical dependencies within multichannel recordings. The ADTF can be derived from the coefficients of a time-variant multivariate autoregressive (TVAR) model fitted to the data. In this paper the applicability to locate the epileptogenic focus by time-variant connectivity analysis of seizure onsets based on the ADTF is shown. Furthermore, different normalizations of the ADTF (the integrated ADTF, the masked ADTF and the full frequency ADTF) are compared to investigate whether one is more suitable to describe the spreading of epileptic activity during an epileptic seizure. We quantified the performance of different connectivity measures during simulations of an epileptic seizure onset. The full frequency ADTF outperforms the integrated ADTF and masked ADTF. Accordingly, we applied this full frequency ADTF to 4 seizure onset and 29 subclinical seizure IEEG recordings of a patient with refractory epilepsy. Hereby, we showed that connectivity patterns derived from IEEG recordings can provide useful information about seizure propagation and may improve the accuracy of the pre-surgical evaluation in patients with refractory epilepsy.     

双侧颞叶海马病变致药物难治性癫的外科治疗

目的探讨双侧颞叶海马病变致药物难治性癫的外科手术治疗方法及效果。方法 5例MRI显示双侧颞叶病变的患者,临床症状、核磁共振成像（MRI）、长程视频脑电监测（V-EEG）及正电子发射断层显像-计算机断层显像（PET-CT）等检查均不能定位起源病灶,行MRI引导立体定向下双侧海马深部电极置入术,对术后V-EEG,综合分析结果,确定起源病灶侧别后行手术治疗。结果术后随访半年以上,按照Engel的疗效判断标准：Ⅰ级4例（行起源侧前颞叶海马杏仁核切除术）,Ⅱ级1例（行起源侧海马神经调控治疗）。结论对双侧颞叶海马病变致药物难治性癫,通过立体定向下双侧海马深部电极置入术及术后长程V-EEG方法,综合分析结果能较准确确定癫起源灶,同时也能成功指导外科手术。     

Epileptogenic networks of type II focal cortical dysplasia: a stereo-EEG study

In the context of focal and drug-resistant epilepsy, surgical resection of the epileptogenic zone may be the only therapeutic option for reducing or suppressing seizures. In many such patients, intracranial stereo-EEG recordings remain the gold standard for the epilepsy surgery work-up. Assessing the extent of the epileptogenic zone and its organisation is a crucial objective, and requires advanced methods of signal processing. Over the last ten years, considerable efforts have been made to develop signal analysis techniques for characterising the connectivity between spatially distributed regions. The aim of this study was to evaluate the changes in dynamic connectivity pattern under inter-ictal, pre-ictal and ictal conditions using signals derived from stereo-EEG recordings of 10 patients with Taylor-type focal cortical dysplasia. A causal linear multivariate method - partial directed coherence - and indices derived from graph theory were used to characterise the synchronisation property of the lesional zone (corresponding to the epileptogenic zone in our patients) and to distinguish it from other regions involved in ictal activity or not. The results show that a significantly different connectivity pattern (mainly in the gamma band) distinguishes the epileptogenic zone from other cortical regions not only during the ictal event, but also during the inter- and pre-ictal periods. This indicates that the lesional nodes play a leading role in generating and propagating ictal EEG activity by acting as the hubs of the epileptic network originating and sustaining seizures. Our findings also indicate that the cortical regions beyond the dysplasia involved in the ictal activity essentially act as "secondary" generators of synchronous activity. The leading role of the lesional zone may account for the good post-surgical outcome of patients with type II focal cortical dysplasia as resecting the dysplasia removes the epileptogenic zone responsible for seizure organisation. Furthermore, our findings strongly suggest that advanced signal processing techniques aimed at studying synchronisation and characterising brain networks could substantially improve the pre-surgical evaluation of patients with focal epilepsy, even in cases without an associated anatomically detectable lesion.     

Localizing epileptogenic regions in partial epilepsy using three-dimensional statistical parametric maps of background EEG source spectra

This preliminary study sought to localize epileptogenic regions in patients with partial epilepsy by analysis of interictal EEG activity utilizing variable resolution electromagnetic tomography (VARETA), a three-dimensional quantitative electroencephalographic (QEEG) frequency-domain distributed source modeling technique. The very narrow band (VNB) spectra spanned the frequency range 0.39 Hz to 19.1 Hz, in 0.39 Hz steps. These VNB spectra were compared to normative data and transformed to provide Z-scores for every scalp derivation, and the spatial distributions of the probable EEG generators of the most abnormal values were displayed on slices from a probabilistic MRI atlas. Each voxel was color-coded to represent the significance of the deviation relative to age appropriate normative values. We compared the resulting three-dimensional images to the localization of epileptogenic regions based on invasive intracranial EEG recordings of seizure onsets. The VARETA image indicated abnormal interictal spectral power values in regions of seizure onset identified by invasive monitoring, mainly in delta and theta range (1.5 to 8.0 Hz). The VARETA localization of the most abnormal voxel was congruent with the epileptogenic regions identified by intracranial recordings with regard to hemisphere in all 6 cases, and with regard to lobe in 5 cases. In contrast, abnormal findings with routine EEG agreed with invasive monitoring with regard to hemisphere in 3 cases and with regard to lobe in 2 cases. These results suggest that analysis of background interictal EEG utilizing distributed source models should be investigated further in clinical epilepsy.     

幕上肿瘤伴发癫(癎)的精确定位和手术疗效分析

目的 探讨幕上肿瘤伴发癫(癎)的精确定位价值和手术治疗效果,研究肿瘤与致(癎)灶的关系.方法 对121例(胶质瘤Ⅰ级15例、Ⅱ级35例、Ⅲ～Ⅳ级12例,脑膜瘤32例,脑转移瘤10例,海绵状血管瘤15例,室管膜瘤2例)临床上以癫(癎)为首发症状的幕上肿瘤患者术前、术后癫(癎)发作情况等,临床资料进行回顾性分析.结果 采用术前影像和脑电结合定位、术中皮层脑电再次定位的方法,对肿瘤和癫(癎)灶同时切除,无手术死亡.癫(癎)发生率最高在额叶,最低在枕叶.癫(癎)灶与肿瘤的关系:位于同一部位者50例;致(癎)灶位于肿瘤一侧或近旁者28例;致(癎)灶位于肿瘤远隔部位(＞2 cm)25例;检测不到致痫灶者18例.失访18例,103例随访1～9年,31例术后早期仍有小发作,83例不再服抗癫(癎)药物癫(癎)症状完全消除.结论 在幕上肿瘤伴发癫(癎)患者中,致(癎)灶与肿瘤灶存在一定的差异性.在开颅切除肿瘤的同时必须明确致(癎)灶的位置和范围,一并切除才能达到良好的手术效果.     

Dynamic imaging of ictal oscillations using non-invasive high-resolution EEG

Scalp electroencephalography (EEG) has been established as a major component of the pre-surgical evaluation for epilepsy surgery. However, its ability to localize seizure onset zones (SOZ) has been significantly restricted by its low spatial resolution and indirect correlation with underlying brain activities. Here we report a novel non-invasive dynamic seizure imaging (DSI) approach based upon high-density EEG recordings. This novel approach was particularly designed to image the dynamic changes of ictal rhythmic discharges that evolve through time, space and frequency. This method was evaluated in a group of 8 epilepsy patients and results were rigorously validated using intracranial EEG (iEEG) (n=3) and surgical outcome (n=7). The DSI localized the ictal activity in concordance with surgically resected zones and ictal iEEG recordings in the cohort of patients. The present promising results support the ability to precisely and accurately image dynamic seizure activity from non-invasive measurements. The successful establishment of such a non-invasive seizure imaging modality for surgical evaluation will have a significant impact in the management of medically intractable epilepsy.