脑立体定向植入海马电极监测颞叶内侧癫痫的临床研究

目的 观察应用脑立体定向微创穿刺技术植入海马电极监测颞叶内侧癫痫的效果.方法 13例耐药性颞叶内侧癫痫患者,主要表现为复杂部分性癫痫发作及继发性全身强直阵挛性发作.根据临床症状、MRI等资料初步确定癫痫灶位于海马区域,在脑立体定向仪引导下于双侧海马植入8-触点深部电极,监测24 ～ 72 h,从而确认癫痫灶是否位于海马区域.结果 13例患者经过72 h监测,共监测到7例有29次临床发作,发作期脑电变化表现为在背景波形基础上出现阵发性高幅慢波或棘尖慢复合波,从某个电极点开始,迅速扩展到同侧其他电极点甚至对侧电极;头皮脑电在延迟1～2s后出现3～4 Hz的高幅δ节律.6例未监测到临床发作的患者,海马电极监测到发作性局灶性高幅慢波或尖慢综合波,而头皮电极未监测到明显异常.13例患者中6例接受选择性海马杏仁核切除或立体定向病灶损毁术,随访3～8个月,效果满意.结论 脑立体定向植入海马电极监测颞叶内侧癫痫是一种安全可靠的方法,可以判断癫痫病灶的起源,为外科进行选择性海马杏仁核切除提供有力依据,对于视频脑电图或其他手段难以记录到癫痫样波形或难以判断癫痫样放电起源的患者可进行脑立体定向深部电极脑电图监测.     

立体定向海马深部电极置入在颞叶癫痫外科中的应用

目的探讨应用立体定向技术双侧海马置入深部电极脑电监测对颞叶癫痫的定侧定位价值。方法对15例无创影像及脑电检查难以定侧定位的颞叶癫痫患者,在MR定位引导下行立体定向双侧海马深部电极置入,视频脑电监测描记发作期及发作间期脑电图,根据监测结果对癫痫灶进行定侧定位,行个体化癫痫外科手术治疗,术后正规口服抗癫痫药物并随访。结果术后随访最长44个月,最短8个月,平均21个月。疗效满意8例（54%）,显著改善5例（33%）,良好2例（13%）。术后1例出现视野缺损,无其他严重并发症。结论立体定向双侧海马深部电极置入及脑电监测,微创、安全、准确,是难治性颞叶癫痫定侧定位的可靠的方法,对制定个体化手术方案具有决定性作用。     

选择性海马杏仁核切除术治疗顽固性颞叶癫痫

目的 探讨选择性涨马杏仁核切除术治疗颞叶癫痫的机理、适应征及手术入路。方法 对２０例经ＥＥＧ和ＭＲ诊断为颞叶内侧癫痫病例实施海马杏仁核切除。结果 １０例颞叶癫痫患接受经颞底入路选择性涨马杏仁核切除,另１０例接受经颞极入路海马杏仁核切除。术后随访,所有患癫痫发作控制满意,无手术并发症发生。结论 选择性海马杏仁２核切中通过消除癫痫灶或阻断癫痫环路来治疗颞叶癫痫,深部电极提示有颞叶内侧放电或ＭＲ发现     

隐源性癫痫致痫灶最常见好发部位及相关病理特征

目的 回顾性分析隐源性癫痫致痫灶最常见的好发部位及手术切除标本的病理改变,探讨隐源性癫痫致痫灶的发病机制.方法 通过向26例头部CT、MRI等影像学检查无特异性表现的患者颅内可疑脑区植入皮层电极及深部电极,行长程视频脑电监测,记录发作间期及发作期脑电图变化,确定癫痫病灶起始区,手术切除致痫灶并送病理,术后定期随访.结果 26例均可以明确致痫灶,其中癫痫发作单独起源于颞叶新皮层及颞叶内侧的13例,占本组病例的50％;送检标本病理结果显示胶质细胞增生、皮层分层紊乱25例,占本组病例的96.15％,其中伴有海马硬化14例.术后随访1年以上,Engel Ⅰ级15例,Engel Ⅱ级8例,Engel Ⅲ级2例,Engel Ⅳ级1例.无严重并发症及手术死亡病例.结论 颞叶新皮层及颞叶内侧是隐源性癫痫致痫灶最常见的好发部位,皮层发育不良是隐源性癫痫手术切除标本中常见的病理改变,其中海马硬化是颞叶内侧常见的病理改变.颞叶新皮层及颞叶内侧病理改变不仅经常相伴出现,而且病理改变轻微.通过外科干预,效果较满意.按Engel分级,位于颞叶新皮层及颞叶内侧的病例手术疗效较其他好,Engel's分级均在Ⅱ级以上.     

颞叶癫痫21例手术治疗分析

目的 探讨颞叶癫痫的外科治疗方法及效果。方法 21例颞叶癫痫患者，术前均行EEG、MRI检查，其中6例行PET检查，经定侧定位后，行手术治疗。其中13例行标准前颞叶切除术，5例行病灶切除 致痫灶切除，3例 行选择性海马杏仁核切除。术中应用皮层电极或深部电极进行监测；神经导航下海马钙化切除1例。结果 术后无明显并发症，均取得满意近期效果。结论 海马硬化是颞叶癫痫发生的主要原因；手术是治疗颞叶癫痫的重要手段，且疗效满意。     

俯卧位立体定向植入海马深部电极的手术特点

目的探讨俯卧位立体定向下经枕部入路,沿海马长轴植入双侧海马深部电极的手术特点和技术要点,分析其优缺点。方法全麻俯卧位下,采用双枕钻孔沿长轴CRW立体定向仪引导下,植入海马深部电极,通过对手术并发症和记录海马深部EEG后二期癫痫病灶切除手术效果的判断,分析该术式的可靠性及安全性。结果14例病例安全植入双海马电极,无严重并发症出现,13例行二期癫痫灶切除手术,10例病例术后Engel分级I-II级。结论俯卧位枕部入路放置双侧海马深部电极,可靠性好,安全性高,值得推荐。     

手术治疗颞叶癫痫的远期疗效及影响因素分析

目的探讨手术治疗颞叶癫痫的远期疗效及影响因素。方法皮层电极及深部电极引导下手术治疗59例颞叶癫痫,其中前颞叶＋海马杏仁核切除术57例,选择性海马杏仁核切除术2例。术后进行长期追踪术后随访6-16年,回顾性研究影响患者预后的因素。结果癫痫控制满意44例,显著改善6例,良好3例,无效6例,有效率89.8%。其中癫痫完全消失36例,占61%。复发4例,无死亡病例,记忆力减退3例,精神症状2例。结论手术治疗颞叶癫痫安全有效,但存在远期复发的可能;少数患者远期可能出现记忆力减退及精神症状等;疗效与病例的选择及致癫灶的准确定位等因素有关。     

立体定向杏仁核海马毁损术治疗颞叶内侧型癫痫的临床研究

目的 探讨立体定向杏仁核海马毁损术治疗颞叶内侧型癫痫的有效性,同时评价深部电极记录的发作间歇期痫性放电定位致痫灶的准确性. 方法 选择南方医院神经外科门诊自1998年7月至2003年10月收治的21例顽固性颞叶癫痫患者,行立体定向杏仁核海马毁损术.术中在毁损靶点前后行深部电极记录,统计发作间歇期痫性放电发生频率. 结果 术后随访21例,其中EngelⅠ级6例,Ⅱ级2例,Ⅲ级5例,Ⅳ级3例,Ⅴ级5例.有效者(Ⅰ+Ⅱ+Ⅲ级)13例,无效者(Ⅳ+Ⅴ级)8例,有效率为62％.深部电极记录的发作间歇期痫性放电手术前后的发生频率差异无统计学意义(P＞0.05). 结论 立体定向射频毁损杏仁核海马手术治疗颞叶内侧型癫痫安全有效.深部电极记录的发作间歇期痫性放电定侧价值较高,而定位价值低.     

颞叶癫痫的手术治疗效果及并发症回顾性分析(附69例临床报告)

目的探讨手术治疗颞叶癫痫的疗效及并发症。方法皮层电极及深部电极引导下手术治疗69例颞叶癫痫,其中前颞叶+海马杏仁核切除术67例,选择性海马杏仁核切除术2例。术前行PET、SPECT、MRI、EEG检查。结果 69例术后随访1~7.6年,满意63例,显著改善2例,良好1例,无效3例,有效率95.7%。其中癫痫完全消失60例,占87%。无死亡,暂时性偏瘫2例,占2.9%,轻度同向视野缺损6例,占8.7%,硬膜外血肿1例,记忆力减退3例。结论手术治疗颞叶癫痫的效果好;疗效与病例的选择及致癫灶的准确定位有关;部分并发症与手术技巧有关。     

神经导航下锁孔入路选择性海马杏仁核切除术治疗内侧颞叶癫痫

目的 探讨神经导航下锁孔入路选择性海马杏仁核切除术治疗顽固性内侧颞叶癫痫的可行性.方法 总结分析18例神经导航下锁孔入路选择性海马杏仁核切除病例,所有病例均经过临床特征、影像检查、视频脑电监测、脑磁图检查确定为顽固性内侧颞叶癫痫.结果 随访结果显示72.2%病例术后癫痫发作停止.Engel癫痫疗效分级:Ⅰ级72.2%,Ⅱ级22.2%,Ⅲ级5.6%.结论 神经导航下锁孔入路选择性海马杏仁核切除术是一种安全可行的手术方法,疗效满意.     

Epilepsy and anomalies of neuronal migration: MRI and clinical aspects

Neuronal migration disorders are the result of disturbed brain development. In such disorders, neurons are abnormally located. In diagnosing these conditions, magnetic resonance imaging is superior to any other imaging technique. This enables us to improve our knowledge of the clinical correlates of neuronal migration. With reference to migrational disorder, a retrospective study of all 303 patients with epileptic seizures referred for magnetic resonance imaging during a 3-year period was performed, 13 patients (aged 12-41, mean age 27) were identified. They represent 4.3% of the entire study group. Of the patients with known epilepsy, 6.7% and of the mentally retarded, 13.7% had migrational disorders. Four patients had schizencephaly as the dominant finding, one was classified as hemimegalencephaly, 2 had isolated heterotopias, and 6 had localized pachy- and/or poly-microgyria. The clinical pictures are complex. Ectopias of grey matter are recognised foci of epilepsy, but from an epileptological and a clinical viewpoint little attention has been given to these disorders. The present study shows that malmigration is not rare in epilepsy patients, especially not in the mentally retarded.     

Hepatic Considerations in the Use of Antiepileptic Drugs

Summary: Virtually all of the major antiepileptic drugs (AEDs) can cause hepatotoxicity, although fatal hepatic reactions are rare. The mechanisms, incidences, and risk profiles for such reactions differ from drug to drug. With carbamazepine and phenytoin, hepatotoxicity may be due to drug hypersensitivity. Although the profiles of patients at risk have not been well-defined for these two antiepileptic drugs, it would appear from reports in the literature that older adolescents and adults are at higher risk than children of developing serious or fatal hepatotoxicity. Once hepatotoxicity develops, mortality rates are 10–38% with phenytoin and 25% for carbamazepine. The risk profile for valproate fatal hepatotoxicity has been more clearly defined. Those at primary risk of fatal hepatic dysfunction are children under the age of 2 years who are receiving multiple anticonvulsants and also have significant medical problems in addition to severe epilepsy. The risk is considerably lower for patients over the age of 2 years on valproate monotherapy. In contrast to the risk profile with other AEDs, adults receiving valproate as monotherapy have the lowest risk of hepatotoxicity. Fatal hepatic dysfunction coincident with valproate may be the result of aberrant drug metabolism. Concomitant use of AEDs that induce microsomal P450 enzymes (e.g., phenytoin and phenobarbital) may enhance the production of a toxic metabolite, and hence the greater risk of hepatotoxicity with polypharmacy.     

Vascular Malformations and Epilepsy: Clinical Considerations and Basic Mechanisms

Summary: Vascular malformations (VMs) are associated with epilepsy. The natural history of the various VMs, clinical presentation, and tendency to provoke epilepsy determine treatment strategies. Investigations have probed the mechanisms of epileptogenesis associated with these lesions. Electrophysiologic changes are associated with epileptogenic cortex adjacent to VMs. Putative pathophysiologic mechanisms of epileptogenesis include neuronal cell loss, glial proliferation and abnormal glial physiology, altered neurotransmitter levels, free radical formation, and aberrant second messenger physiology.     

Classification of methods in transcranial Electrical Stimulation (tES) and evolving strategy from historical approaches to contemporary innovations

Transcranial Electrical Stimulation (tES) encompasses all methods of non-invasive current application to the brain used in research and clinical practice. We present the first comprehensive and technical review, explaining the evolution of tES in both terminology and dosage over the past 100 years of research to present day. Current transcranial Pulsed Current Stimulation (tPCS) approaches such as Cranial Electrotherapy Stimulation (CES) descended from Electrosleep (ES) through Cranial Electro-stimulation Therapy (CET), Transcerebral Electrotherapy (TCET), and NeuroElectric Therapy (NET) while others like Transcutaneous Cranial Electrical Stimulation (TCES) descended from Electroanesthesia (EA) through Limoge, and Interferential Stimulation. Prior to a contemporary resurgence in interest, variations of transcranial Direct Current Stimulation were explored intermittently, including Polarizing current, Galvanic Vestibular Stimulation (GVS), and Transcranial Micropolarization. The development of these approaches alongside Electroconvulsive Therapy (ECT) and pharmacological developments are considered. Both the roots and unique features of contemporary approaches such as transcranial Alternating Current Stimulation (tACS) and transcranial Random Noise Stimulation (tRNS) are discussed. Trends and incremental developments in electrode montage and waveform spanning decades are presented leading to the present day. Commercial devices, seminal conferences, and regulatory decisions are noted. We conclude with six rules on how increasing medical and technological sophistication may now be leveraged for broader success and adoption of tES.     

Carbamazepine Efficacy and Utilization in Children

Summary: Carbamazepine is effective for preventing partial and generalized tonic-clonic seizures in children. Although absence epilepsies are more common in children than adults, an estimated 80% of children with epilepsy have seizure types or epilepsies that are potentially responsive to carbamazepine. The differential diagnosis of ictal staring is an especially important issue in children because absence and atypical absence seizures are more prevalent in children than adults. Age-related pharmacokinetic differences and drug interactions are major considerations in children. On average, children have higher clearance rates of carbamazepine, shorter half-lives, and higher ratios of carbamazepine-10, 11-epoxide to carbamazepine than adults. In addition, children with severe epilepsy are more likely to require multiple-drug therapy, which can lead to complex drug interactions. When carbamazepine is administered along with valproate, drug protein binding interactions can cause intermittent side effects.     

Neonatal Seizures: Problems in Diagnosis and Classification

Summary: The clinical identification of neonatal seizures is critical for the recognition of brain dysfunction; however, diagnosis is often difficult because of the poorly organized and varied nature of these behaviors. Current classification systems are limited in their ability to communicate motor, autonomic, and electroencephalo-graphic features of seizures precisely and to provide a basis for uniform effective diagnosis, therapy, and determination of prognosis. Recent investigations of neonates, utilizing bedside electroencephalographic/polygraphic/ video monitoring techniques, have provided the basis for improved diagnosis and classification of seizures in the newborn. These studies have demonstrated that not all clinical phenomena currently considered to be seizures require electrocortical epileptiform activity for their initiation or elaboration. In addition, the specific clinical character of the phenomena considered to be seizures, the clinical state of the infant, and the character of the EEG indicate the probable pathophysiological mechanisms involved and suggest probable etiologies, prognosis, and therapy. Similarities between animal models that demonstrate reflex physiology and neonates with motor automatisms and tonic posturing suggest that these clinical behaviors may not be epileptic in origin but, rather, primitive movements of progression and posture mediated by brainstem mechanisms. Although not all clinical behaviors currently considered to be neonatal seizures may have similar pathophysiological mechanisms, they are clinically significant because they all indicate brain dysfunction.     

Valproate Monotherapy in the Management of Generalized and Partial Seizures

Summary: For decades, therapeutic tradition has promoted the concept of polypharmacy in the management of epilepsy. In recent years, however, studies have shown that, for most patients, monotherapy can provide comparable or better seizure control than administration of multiple anticonvulsants, while diminishing the potential for adverse reactions, drug interactions, and poor compliance. Valproate is an important monotherapeutic agent that is highly effective in the control of idiopathic primary and secondarily generalized epilepsies, and partial seizures that do not generalize. Comparative studies have found that valproate is at least as effective as phenytoin and carbamazepine in the treatment of generalized and partial seizures. Given the similar efficacy, other factors such as pharmacokinetics and side effects may therefore determine anticonvulsant selection for monotherapy.     

Un nouveau cadre conceptuel de travail pour la psychiatrie

In an attempt to place psychiatric thinking and the training of future psychiatrists more centrally into the context of modern biology, the author outlines the beginnings of a new intellectual framework for psychiatry that derives from current biological thinking about the relationship of mind to brain. The purpose of this framework is twofold. First, it is designed to emphasize that the professional requirements for future psychiatrists will demand a greater knowledge of the structure and functioning of the brain than is currently available in most training programs. Second, it is designed to illustrate that the unique domain which psychiatry occupies within academic medicine, the analysis of the interaction between social and biological determinants of behavior, can best be studied by also having a full understanding of the biological components of behavior.     

Special Pharmacokinetic Considerations in Children

Summary: Pediatric patients have greater degrees of pharmacokinetic variability and unpredictability than adults. This variability results from the effects of pharmacogenetics, age and growth, prior and current comedication, and disease. Newborns with seizures have the least predictable dosage requirements, and their needs change as drug-eliminating mechanisms mature in the neonatal period. Infants have the highest relative capacities to eliminate antiepileptics of any age group and require the largest relative doses. In addition to age-related trends, children demonstrate the same drug-specific, pharmacokinetic phenomena that adults do, including nonlinear phenytoin elimination, nonlinear valproate binding, and autoinduction of carbamazepine. Intercurrent illness and drug interactions further modify the age-related pharmacokinetic patterns in children and make dosage requirements even more unpredictable. Recent studies have shown that febrile illness can affect drug elimination, sometimes decreasing drug levels by 50% or more. Intermittent treatment with benzodiazepines administered either orally or rectally can be an important adjunct and help minimize this type of problem for children with marginally controlled epilepsy. Intermittent benzodiazepines are also helpful for children who have febrile seizures and who need only occasional antiepileptic protection.