便携式视频显微镜经大脑纵裂胼胝体上段、经胼体入路的解剖研究

目的研究便携式视频显微镜经大脑纵裂胼胝体上段、经胼胝体入路的显露范围和观察效果。方法将新鲜和灌注固定的成人尸头标本各5例,在便携式视频显微镜下,经大脑纵裂胼胝体上段、经胼胝体入路暴露并观察侧脑室和第三脑室。结果经大脑纵裂胼胝体上段、经胼胝体入路,在便携式视频显微镜下解剖观察,侧脑室和第三脑室的结构显示清楚,图像逼真。结论便携式视频显微镜经大脑纵裂胼胝体上段、经胼胝体入路能够完成侧脑室和第三脑室的显微解剖。     

经纵裂-胼胝体前部入路切除侧脑室中枢神经细胞瘤

目的 探讨应用经纵裂-胼胝体前部入路切除侧脑室中枢神经细胞瘤的效果.方法 对经纵裂-胼胝体前部入路手术切除16例中枢神经细胞瘤患者的临床资料进行回顾性分析.结果 16例患者,肿瘤最大径2 ～4 cm7例,＞4 cm9例;病变基底位于透明隔9例,位于一侧脑室的外侧壁7例,脑室扩大8例;全切12例,次全切4例(术后行放疗),无手术死亡,术后均出现短暂缄默症,2周后消失;5例出现偏瘫,经康复后可以行走;4例发生脑积水,行脑室-腹腔分流术.随访14例,时间为1-7年,无复发.结论 应用经纵裂-胼胝体前部入路手术,利用颅腔自然间隙,脑组织损伤少,术后反应轻,是切除侧脑室中枢神经细胞瘤的较好入路;肿瘤与侧脑室外侧壁和下壁的粘连是影响肿瘤全切的因素.     

经胼胝体-穹隆间人路的显微解剖学研究

目的为经胼胝体．穹隆间入路的临床应用提供显微解剖学资料，以利于术中重要血管、神经结构的辨认和保护。方法模拟经胼胝体一穹隆间入路，对15例国人成人头颅湿标本进行显微解剖，详细观察与本人路相关的重要解剖结构，并进行测量和拍照。结果在胼胝体中部两侧纵纹之间的沟槽内有一标志中线的细小动脉；以分别位于大脑半球内侧面中央沟上端之前5cm和7cm的两点（PS／P7）为参照，得到的相关测量值的均数如下：（1）PS／P7至扣带沟的距离分别为29．26mm、30．43ram；（2）胼胝体下缘和穹隆间的距离分别为7．53mm、9．88mm；（3）胼胝体的高度分别为7．18mm、7．78mm；（4）前连合和室间孔的距离为5．04mm。结论经胼胝体入路应限定在P5-室间孔和P7．室间孔两连线之间的范围内；胼胝体中部两侧纵纹之间沟槽内的小动脉可作为切开胼胝体的标记；熟悉上述数据资料有助于术中保护运动区、胼胝体膝、穹隆连合、前连合。     

经胼胝体-脉络膜裂入路的显微解剖学研究

目的 探讨经胼胝体-脉络膜裂入路的显微解剖学特征和临床应用价值.方法 显微镜下对12例成人尸头湿标本进行侧脑室、第三脑室区显微解剖,观察侧脑室、脉络丛、脉络膜裂及第三脑室顶的解剖学特点;在3例成人尸头新鲜标本上模拟经胼胝体-脉络膜裂入路手术,观察与本人路相关的重要解剖结构并测量相关距离.结果 脉络丛位于侧脑室底部内侧,脉络膜裂位于丘脑和穹窿之间,可借助与之相连的脉络丛进行辨认.切开脉络膜裂穹窿带到达第三脑室顶中间帆后,于两侧大脑内静脉间分离打开第三脑室顶即到达第三脑室腔.经测量,大脑内侧缘冠状缝处至胼胝体沟的距离为(39.12±3.94)mm,大脑内侧缘冠状缝处至室间孔的距离为(61.53±4.02)mm,室间孔后缘至穹窿与胼胝体融合处的距离为(28.65±2.23)mm,前后连合的距离为(25.94±2.16)mm,室间孔至乳头体的长度为(19.62±1.79)mm.结论 与其他手术人路相比,经胼胝体-脉络膜裂入路循自然裂隙进入第三脑室,具有路径直接、术野暴露广泛等特点,值得临床推广应用.     

胼胝体穹隆间入路到三脑室的显微解剖

目的研究经胼胝体穹隆间入路到三脑室的显微解剖,为临床提供切除三脑室肿瘤的应用价值。方法对12例成人尸头,在5～25倍显微镜下进行解剖,测量冠状缝与矢状缝交点到胼胝体表面的距离、胼胝体的厚度、前联合后缘到室间孔后缘的距离、分离透明膈间腔、观察统计冠状缝前后的引流静脉。结果该入路可在直视下进入三脑室。(1)冠状缝到胼胝体表面的距离43．7mm,范围：40．1～45．9mm；(2)胼胝体厚度大约(5．1±1．6)mm,平均厚度：5．3mm；(3)前联合后缘至室间孔后缘的平均距离为10．2mm,范围：9．5～11．5mm；(4)三个标本没有分开透明膈间腔,在剩下的标本中,在高倍显微镜下用显微剥离子分开透明膈间腔；(5)冠状缝前5cm引流静脉很少,而冠状缝后引流到矢状窦的静脉却异常密集。结论胼胝体-穹隆间入路按生理间隙进入,直视下操作,对周围重要结构损伤很小,是手术切除三脑室肿瘤的最佳入路。     

经胼胝体-穹隆间入路的显微解剖学研究

目的为经胼胝体-穹隆间入路的临床应用提供显微解剖学资料,以利于术中重要血管、神经结构的辨认和保护。方法模拟经胼胝体-穹隆间入路,对15例国人成人头颅湿标本进行显微解剖,详细观察与本入路相关的重要解剖结构,并进行测量和拍照。结果在胼胝体中部两侧纵纹之间的沟槽内有一标志中线的细小动脉;以分别位于大脑半球内侧面中央沟上端之前5cm和7cm的两点(P5/P7)为参照,得到的相关测量值的均数如下:(1)P5/P7至扣带沟的距离分别为29.26mm、30.43mm;(2)胼胝体下缘和穹隆间的距离分别为7.53mm、9.88mm;(3)胼胝体的高度分别为7.18mm、7.78mm;(4)前连合和室间孔的距离为5.04mm。结论经胼胝体入路应限定在P5-室间孔和P7-室间孔两连线之间的范围内;胼胝体中部两侧纵纹之间沟槽内的小动脉可作为切开胼胝体的标记;熟悉上述数据资料有助于术中保护运动区、胼胝体膝、穹隆连合、前连合。     

便携式视频显微镜经大脑纵裂胼胝体前段入路至蝶鞍的解剖研究

目的应用便携式视频显微镜进行经大脑纵裂胼胝体前段入路至蝶鞍的解剖研究。方法新鲜和灌注固定的成人尸头标本各5例,在便携式视频显微镜下,经大脑纵裂胼胝体前段入路解剖并观察鸡冠至蝶鞍。结果便携式视频显微镜经大脑纵裂胼胝体前段入路能够清楚、逼真地暴露蝶鞍的解剖结构。结论应用便携式视频显微镜经大脑纵裂胼胝体前段入路能够完成蝶鞍的显微解剖研究。     

后纵裂经胼胝体入路处理松果体区肿瘤的解剖与临床

目的 通过对后纵裂经胼胝体入路的解剖和临床研究,为处理松果体区病变提供切实可行的外科策略.方法 取10具血管经彩色乳胶灌注的成人尸头,在6～25倍显微镜下模拟后纵裂经胼胝体入路,测量入路中相关重要结构间的距离,并回顾性分析和比较后纵裂经胼胝体入路与幕下小脑上入路处理的15例松果体区病变的临床治疗效果.结果 后纵裂经胼胝体入路可以人字缝作为人路的标志点,并以人字缝与鼻根部连线的方向作为入路的方向.在标本和T2RMRI上,人字缝至松果体中心部的距离平均分别是71.40 mm和70.14 mm.15例松果体区肿瘤中,11例采用幕下小脑上入路,其中4例全切,重残1例,死亡2例;4例采用后纵裂经胼胝体入路者均做到了肿瘤的全切,重残1例,无死亡.结论 松果体区肿瘤手术人路的选择主要取决于肿瘤的部位和侵及的范围,尤其要注意其与脑室系统、中线、胼胝体及Galen静脉的关系,而术前T2RMRI和MRV或DSA可为手术入路的选择提供可靠的依据.     

经胼胝体侧脑室入路至丘脑区域的显微镜与内镜解剖学研究

目的观察经胼胝体侧脑室入路至丘脑的相关解剖标志,比较显微镜与內镜在暴露方面的互补性,为临床应用提供解剖学基础。方法 6具(12侧)红、蓝色乳胶灌注的头颅标本,模拟经胼胝体侧脑室入路暴露丘脑,显微镜联合内镜依次交替观察纵裂、透明隔间腔、侧脑室、三脑室四个阶段的解剖结构,并测量相应数据。结果纵裂阶段:胼缘动脉、扣带回、胼周动脉和胼胝体为主要解剖标志。透明隔间腔阶段:透明隔和穹窿体为主要解剖标志。显微镜和內镜均能较好的暴露纵裂和透明隔间腔内的解剖结构。侧脑室阶段:室间孔、透明隔静脉、丘纹静脉、脉络丛、穹窿体、尾状核体部为主要解剖标志。内镜可以弥补显微镜下额角前部(25.7mm±1.7mm vs.14.2mm±1.2mm,P0.05)、丘脑外侧1/3(12.1mm±0.7mm vs.7.0mm±0.9mm,P0.05)和后侧2/5(28.8mm±1.4mm vs.18.7mm±1.4mm,P0.05)的视野死角。三脑室阶段:由于受穹窿体和大脑内静脉的限制,显微镜和内镜都不足以有效暴露丘脑内侧面。结论经胼胝体侧脑室入路暴露丘脑的过程中解剖标志明确,显微镜和内镜的配合有助于辨认重要解剖结构、弥补术野死角。     

经纵裂胼胝体侧脑室锁孔入路的解剖学研究

目的研究经胼胝体侧脑室锁孔入路相关解剖因素在手术暴露中的作用,并探索该入路的设计原则和方法。方法尸头模拟经胼胝体侧脑室锁孔入路手术,观测相关解剖因素,以矢状位术野角和冠状位术野角为评价指标,对数据进行统计分析;据此设计标准经胼胝体侧脑室锁孔入路。结果回归分析:矢状位术野角=184.41 + 0.63 ×骨窗长度+ 7.44 ×同侧/对侧骨窗-0.62 ×胼胝体切口位置角-1.76 ×骨窗-胼胝体切口间距-1.13 ×胼胝体切口;冠状位术野角=-78.46 + 1.79 ×骨窗-胼胝体切口间距+ 0.99 ×胼胝体切口长度+ 0.14 ×骨窗长度。由此建立了额角、体部、房部和枕角的标准经胼胝体侧脑室锁孔入路。结论矢状位术野角和冠状位术野角可客观评价经胼胝体侧脑室锁孔入路的暴露水平;矢状位术野角和冠状位术野角回归方程有助于理解、把握影响手术暴露的众多解剖因素;标准锁孔入路能够完成侧脑室额角、体部、房部和枕角的手术暴露。     

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.     

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.     

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.     

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.     

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.     

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.