脑死亡患者脑电图频谱分析

目的 通过对脑死亡患者脑电图进行定量分析,寻找敏感可靠的脑死亡诊断标准.方法 对17例确诊为脑死亡患者及5例临床脑死亡患者进行脑电图频谱分析,并与13例非脑死亡患者的脑电图资料进行比较.结果 脑死亡组的脑电功率值显著低于非脑死亡组(均P<0.01).临床脑死亡组脑电功率值介于脑死亡组与非脑死亡组之间,脑电功率值高者预后较好,脑电功率值低者预后较差.结论 脑电图频谱分析可能对脑死亡的判断、特别是临床脑死亡患者预后的判断有一定价值.     

脑电图在评估脑死亡中的应用

目的评价脑电图(EEG)在判定脑死亡中的作用。方法选择浙江省各大医院临床诊断为脑死亡患者88例。其中男性54例,女性34例,年龄16～82岁,平均(43．6±18．5)岁。采用意大利EB Neuro公司Belight便携式脑电图仪,按国际10／20标准,用针电极进行描记,对88例临床诊断脑死亡患者相隔12 h行2次EEG检测。结果以脑电静息,即不出现>2μV的脑波活动作为脑死亡的EEG诊断标准。88例中有81例(92．04％)患者在相隔12 h行2次EEG检查,其结果均呈脑电静息表现。其中6例(6．82％)患者EEG检查存在低幅脑波活动。另1例(1．14％)首次EEG检查干扰太大影响结果判断,间隔12 h检查即显示脑电静息。结论EEG用于评估脑死亡具有较高的敏感性,在严格控制仪器参数及检测条件和动态观察的情况下,可将其作为判断脑死亡的一项重要辅助检查手段。     

反射性癫痫的24h脑电图监测

目的 探讨反射性癫痫的ＥＥＧ变化。方法 对３４例不同类型反射性癫痫在特定刺激下作动态ＥＥＧ监测，以常规ＥＥＧ作比较。结果 动态ＥＥＧ异常率（６２％）与痫样放电检出率（５３％）均高于常规ＥＥＧ的３５％与２６％。痫样放电的部位主要涉及到额、前颞。诱发异常占所有动ＥＥＧ异常的７６％。结论 ＡＥＥＧ对提示反射性癫痫是原发还是继发及对预后判断有帮助。     

脑死亡标准研究的历史回顾

脑死亡的概念是1959年法国学者Mollaret和Goulon提出的，当时命名为“超昏迷”(le eoma depasse)。1968年美国哈佛大学医学院正式制定了脑死亡诊断标准。但是，实际上“脑死亡”这一现象或综合征早在19世纪，自从开始用人工方法辅助停止的呼吸时就已出现。最早创用人工呼吸的是Hall(1856)，他使用旋转推动患者躯体的方法促使患者被动呼气：1858年Silvester使用人工呼吸方法使患者维持生命数小时至1d。1898年Duckworth采用反复按压胸骨及人工呼吸抢救一些因脑部疾病所致呼吸停止的患者，使循环功能维持数小时。     

小儿长程视频脑电图监测的护理

癫痫的诊断主要依靠病史的提供，很多病人本身不能回忆发作时的情景，儿童患儿更无法正常叙述清楚，只能由家长或旁观背描述，常难客观表达发作时的状态，     

脑死亡脑电非线性定量分析

目的:运用近似熵(ApEn)和C0复杂度对脑死亡患者脑电图(EEG)进行非线性定量分析,期望寻找一种可靠而又敏感的脑死亡诊断标准。方法:研究对象35例,其中男性21例,女性14例;年龄16～85岁。根据其临床表现和EEG结果分为脑死亡组、临床脑死亡组和非脑死亡组。对每组进行ApEn和C0复杂度分析,并比较3组结果。结果:脑死亡组患者17例,男性11例,女性6例;年龄21～82岁。临床脑死亡组5例,男性3例,女性2例;年龄16～85岁。非脑死亡组13例,男性7例,女性6例;年龄17～84岁。脑死亡组的ApEn值约为1.0,非脑死亡组的ApEn值约为0.3,临床脑死亡组ApEn值介于两者之间。脑死亡组C0复杂度值约为0.17,非脑死亡组C0复杂度值约为0.06,临床脑死亡组介于两者之间。无论是ApEn还是C0复杂度,数值上越接近脑死亡组者预后越差,反之越好。讨论:ApEn和C0复杂度对EEG进行非线性定量分析都是判定脑死亡较好的辅助检查。     

Prediction of Surgical Outcome by Interictal Epileptiform Abnormalities During Intracranial EEG Monitoring in Patients with Extrahippocampal Seizures

PURPOSE: Ictal intracranial EEG recordings obtained during continuous preoperative monitoring are often used to localize the region of seizure onset for purposes of surgical resection in patients with extrahippocampal seizures. Whether interictal epileptiform abnormalities during long-term monitoring can predict surgical outcome in this group is not established. METHODS: Intracranial EEGs of patients who underwent extrahippocampal resective epilepsy surgery were reviewed for interictal epileptiform abnormalities before medication discontinuation or first seizure occurrence. Interictal abnormalities were categorized as within or beyond the confines of surgical resection. We correlated these findings with the region of seizure onset, the pathologic substrate, and surgical outcome (by using Engel criteria) at 1-year minimum follow-up. RESULTS: Of 13 patients with interictal epileptiform abnormalities, six patients had interictal epileptiform discharges extending beyond the confines of surgical resection. These patients all had poor surgical outcome even if the region of electrographic seizure onset was resected. Seven patients had focal interictal epileptiform discharges, the entire extent of which were resected. All had good outcomes. All patients with structural lesions had focal interictal epileptiform abnormalities and good surgical outcomes. The spatial extent of interictal epileptiform discharges varied among patients with nonstructural lesions. However, those whose regions of interictal epileptiform abnormality were included in surgical resection also had good surgical outcome. CONCLUSIONS: The presence of interictal epileptiform discharges extending beyond the area of resection correlates with poor surgical outcome in patients with extrahippocampal epilepsy. In contrast, patients with focal interictal epileptiform discharges included in surgical resection have good surgical outcomes.     

EEG Abnormalities in Nonepileptic Patients

Abstract: A total of 202 nonepileptic patients (120 males and 82 females) who exhibited spike abnormalities at least twice in their EEG examinations were studied. The incidence of spike abnormalities among nonepileptic patients was 8.1% (847/10,473). The majority (90%) were under age 19. Headache, dizziness and vomiting, and abdominal pain were more frequently observed compared with controls. Mild paroxysmal EEG abnormalities such as diffuse irregular slow wave bursts with spike (27%), positive spikes (25%) or small spike (8.4%) were commonly detected.
In three patients who developed epileptic seizures during the follow-up period, more specific EEG abnormalities were often exhibited. Other factors like the age at onset before 9, characteristic clinical symptoms or a positive family history of seizures were confirmed to be necessary for the manifestation of clinical seizures.     

Computerized EEG and Brain Imaging Studies in Untreated Schizophrenic Patients: A Report of Seven Cases

Abstract: We undertook routine EEG, Z-map, CT and PET scans in seven acute untreated schizophrenics. Routine EEGs showed slower activity in only one case. However, the Z-map showed slower activity in all the cases. CT demonstrated brain atrophy in three of the cases, and PET revealed hypofrontality in two, right hypoparietality in four, and both conditions in one case. There was no relation between CT and PET or the Z-map. However, a significant increase in alpha 1 activity was demonstrated on the Z-map in cases who were found to be the parietal type on PET; this was not conspicuous in the frontal type on PET. Moreover, in three of the patients, the Z-map findings were similar to the lesion indicated on PET.     

Seizure Lateralization During EEG Monitoring in Patients with Bilateral Foci: The Cluster Effect

: Purpose: To determine whether seizures that occur in clusters are more likely to reflect activity of the same focus than are seizures that are widely separated in time. Methods: EEG monitoring data from 14 patients with bilateral independent seizure onsets were analyzed. Twelve of the 14 patients had surface recordings only, and two had implanted electrodes. Interseizure intervals (ISIs) for 151 seizure pairs were measured. Seizure onsets were classified as right hemispheric, left hemispheric, or indeterminate. Seizure pairs were classified as concordant for hemisphere of onset, discordant, or indeterminate. The relation between seizure-pair concordance and ISI was examined by using univariate analysis and analysis of variance (ANOVA). Results: Both seizures originated from the same hemisphere in 61 (75%) of 81 seizure pairs with ISIs >8 h, compared with 28 (55%) of 51 seizure pairs with ISIs >8 h (p < 0.015). The cluster effect was not more pronounced for ISIs <2 h. ANOVA demonstrated that the relation between IS1 and seizure concordance was not a result of the variability in seizure rates among patients. In three patients, the presence of bilateral foci was not demonstrated until more than five seizures were recorded. Conclusions: Seizures that occur after an IS1 of <8 h are more likely to come from the same side as the previous seizure than are those with longer ISIs. Thus clustered seizures should not be given the same weight as seizures widely separated in time. In addition, more than five seizures may sometimes be needed to adequately assess patients being evaluated for epilepsy surgery.     

EEG-NeuroBioFeedback Treatment of Patients with Brain Injury: Part 2: Changes in EEG Parameters versus Rehabilitation

ABSTRACT

Background. A sample of 27 patients with brain injury distributed in five clinical classes was examined for pre- and post-treatment symptoms and associated power spectra.

Methods. Changes in electroencephalographic (EEG) compressed spectral arrays were analyzed with respect to the rate of rehabilitation and correlated with a checklist of symptoms for each patient and the group as a whole.

Results. Targeted decreases in slower (3–7 Hz) and higher (24–32 Hz) frequencies, and EMG (70–90 Hz), and increases of alpha (8–12 Hz) and mid-range beta frequencies (15–18 Hz) were achieved following Neuro-BioFeedback (NBF) treatment using positive reward tones and a simultaneous visual reward. The impact of gender and age class influence was assessed against treatment results. Single lead EEG power spectra changes were analyzed for hemispherectomized patients, stroke, car accident and trauma patients. A common EEG pattern was observed for a group of patients exhibiting vertigo with two subgroups in which vertigo resolved or did not resolve showing EEG differences.

Conclusions. EEG NeuroBioFeedback can successfully treat patients with brain injury with highly clinically-meaningful clinical results. Changes in Cz power spectra generally occur, but do not always immediately follow resolution of symptoms. Since EEG-NBF is limited to recording cortical surface potentials, it is possible that changes induced by the treatment which result in clinical changes may not always be reflected at the cortical surface and hence may not be available for recording and analysis there, despite subcortical integration.