颞下锁孔入路的显微解剖学研究

目的进行颞下锁孔入路解剖学结构研究,为临床颞下锁孔入路手术入路提供解剖依据。方法在显微镜下对6例经甲醛固定的国人成人尸头模拟颞下锁孔入路手术进行解剖,测量重要神经血管及其相关结构之间的距离以及观察显露范围和相关解剖关系。结果颧弓至小脑幕缘、脑干和前床突的最短距离分别为41.1±5.1mm、45.6±3.3mm和61.1±7.4mm。颞骨岩部扩大磨除前后显露的Day菱形区面积有显著差异(P0.05)。颞下锁孔入路可清楚的显露海绵窦外侧壁上的各神经血管及三角,鞍侧区可清晰的显露颈内动脉、后交通动脉及其穿支、脉络膜前动脉和垂体柄,磨除颞骨岩尖部可显著增加岩斜区脑干显露。结论颞下锁孔入路对于海绵窦外侧壁,岩斜区及鞍侧区显露效果好,入路简单直接,组织损伤小。     

神经内镜辅助下乙状窦前迷路后锁孔入路处理岩斜区病变的应用解剖研究

目的 为神经内镜辅助下乙状窦前迷路后锁孔手术入路处理岩斜区病变提供解剖学基础.方法 取10例(20侧)经福尔马林固定成人头颅标本,采用耳后"C"形切口,切口长度约6cm,模拟乙状窦前迷路后入路,神经内镜及显微镜下观察所显露的解剖结构.结果 乙状窦前缘与后半规管平面的水平距离为:右侧(9.1±1.3)mm,左侧(9.6±1.8)mm.通过调整神经内镜及显微镜角度,经乙状窦前迷路后锁孔入路可显露岩斜区的一些重要结构,清晰显示脑神经及其附近走行的血管.结论 面、前庭蜗神经及内耳道后唇均可以作为神经内镜下经乙状窦前迷路后入路定位岩斜区及其周围结构的标识.     

颞下经前岩骨锁孔入路的显微解剖学研究

目的探讨颞下锁孔入路中前岩骨磨除范围、中上岩斜区显露的区域及手术技巧,为临床应用提供依据。方法对10具经10%甲醛固定的成人尸头标本模拟颞下经前岩骨锁孔入路,在显微镜下观察并测量显露的解剖结构。结果Kawase菱形区的面积为(248.2±12.4)mm2,最大限度磨除前岩骨后的面积为(318.4±36.2)mm2,两者比较有统计学意义。切开后颅窝硬膜,可以暴露上斜坡、内听道下方的部分中斜坡、基底动脉中部、脑桥下部、脑桥延髓沟、延髓上部、椎基底动脉交接部、椎动脉近端、小脑前下动脉脑桥前段和脑桥外侧段。磨除三叉神经压迹下方的骨质,可进一步暴露展神经、Dorello管孔、小脑前下动脉的起始点。结论颞下锁孔入路通过一个直径2.0~2.5cm的小骨窗,可以最大限度磨除前岩骨和暴露上、中斜坡。     

中脑背外侧区病变手术入路的显微解剖研究

目的 通过显微解剖研究比较远后颞下和极外侧小脑上幕下两种手术入路,为外科治疗中脑背外侧区病变提供解剖学基础.方法 神经导航辅助下对10例尸头模拟远后颞下入路和极外侧小脑上幕下入路,测量比较两者的暴露范围.结果 Labbe静脉位于远后颞下入路视野中,使颞叶牵拉受限,离断后可较好暴露中脑背外侧区;极外侧小脑上幕下入路可充分暴露中脑、脑桥上段背外侧及对应的小脑幕切迹区域结构,轮廓化乙状窦和横窦扩大了对此区的显露.结论 远后颞下入路可暴露中脑背外侧区,Labbe静脉损伤是此入路的主要缺陷.极外侧小脑上幕下入路适合于中脑背外侧及对应的小脑幕切迹区病变手术;轮廓化横窦乙状窦,有利于术野的显露.     

经颞下和乙状窦前入路显露岩尖部的虚拟现实解剖学研究

目的在虚拟现实解剖模型中量化比较经颞下入路与经乙状窦前入路显露岩尖部的显微解剖学特征。方法利用15例(30侧)尸头CT和MRI影像构建岩尖部虚拟现实三维解剖模型。在颅盖上分别选取颞骨颧突根部上缘和乳突尖部为经颞下和乙状窦前入路的开颅标记点,颅底上选择岩尖部为显露标记点,以开颅和显露标记点连线为轴线作圆柱模拟经颞下和乙状窦前入路手术路径,观察和测量两种手术路径中解剖结构显露情况,采用配对t检验进行比较分析。结果经颞下入路手术路径经过颅中窝底和颞叶到达岩尖部,磨开岩骨后显露内耳道、面神经和迷路,向前显露三叉神经、岩上窦和海绵窦。经乙状窦前入路经乳突磨除岩骨,经面神经垂直段向深部依次显露颈静脉球、后组脑神经、听骨链、迷路和颈内动脉,路径到达内耳道时显露小脑前下动脉和面听神经复合体,到达岩尖部时包含小脑上动脉、岩上窦、岩下窦、海绵窦、三叉神经和部分颞叶。经乙状窦前入路手术路径中骨性结构、面听神经复合体、迷路和静脉体积均大于经颞下入路(P=0.000),颞叶、三叉神经和听骨链体积均小于经颞下入路(P=0.000)。经乙状窦前入路中包含后组脑神经体积为(32.38±2.86)mm~3、包含颅底动脉体积为(262.74±16.93)mm~3,经颞下入路不包含上述结构。结论经乙状窦前入路对岩骨周围和岩骨内结构的显露范围多于经颞下入路,对重要结构保护较好;经颞下入路经过颞叶到达岩尖部,适用于治疗累及岩骨并将颞叶向上推挤的颅中窝病变。     

颞下经小脑幕锁孔入路解剖与临床应用

目的通过神经导航下颞下经小脑幕锁孔入路的解剖和手术方案研究,探讨该入路临床应用效果。方法应用成人头颅标本12例(24侧),模拟颞下经小脑幕锁孔入路,观察暴露的岩斜区解剖结构;利用神经导航技术定位标本岩骨内部结构,最大限度磨除岩尖,观察斜坡鞍后区,上、中斜坡区等结构;利用该入路切除11例临床颅底肿瘤,探讨该入路的安全性和实用性。结果颞下经小脑幕锁孔入路可完全暴露鞍旁区,通过海绵窦外侧壁的手术三角可对累及海绵窦内外病变进行直视手术;神经导航辅助下耳蜗、内听道等结构定位准确,头颅标本岩尖磨除后耳蜗内侧缘岩尖剩余最大骨质平均厚度(0.8±0.19)mm,内侧视角较非导航入路增加(8±2.5)°,后外侧视野增加了(25±3.2)°,获得(3.3±0.4)cm2硬膜显露,明显扩大了后颅窝的暴露范围。临床病例资料肿瘤全切除6例,次全切3例,大部分切除2例,手术时间与既往相比缩短1~1.5 h,术后新增脑神经损害症状或原有脑神经损害症状加重3例,无长期昏迷及手术相关死亡病例。结论神经导航辅助下颞下经小脑幕锁孔入路,能最大程度暴露蝶岩斜区病变,有利于提高肿瘤的全切率和术后疗效。     

颞底内侧区后部小脑上经小脑幕人路手术的显微解剖学研究

目的 观察颞底内侧区后部小脑上经小脑幕入路手术的显露范围、解剖结构及其位置关系,拟为临床应用提供解剖学依据.方法 5具(10侧)国人男性尸头标本,模拟颞底内侧区后部小脑上经小脑幕入路,于手术显微镜下观察经该入路手术的显露范围、解剖结构,以及颞底内侧区后部脑沟、脑回和动静脉之间的解剖关系.选择3例颞底内侧区后部肿瘤患者,施行小脑上经小脑幕入路手术,观察手术疗效及预后.结果 小脑上经小脑幕入路手术可直接到达颞底内侧区后部,显露海马旁同后部、舌状同前部、梭状回及大脑后动脉P3段及其颞下分支.5具(10侧)尸头标本均存在鼻状沟和侧副沟,但是二者不连续,鼻状沟于前部将海马旁回与梭状回分开,侧副沟于后部将二者分开,前距状沟将海马旁回与舌状回分开,扣带回峡、舌状回前部分别与海马旁回后部汇合,枕颞沟将梭状同与颞下回分开.颞底内侧区后部主要山大脑后动脉颞下分支供血,其中3具(4侧)自大脑后动脉P2段发出颞下总动脉,后者发出颞下前动脉和颞下后动脉供应颞底;2具(2侧)自大脑后动脉P2段发出颞下中动脉和颞下后动脉供应颞底;3具(4侧)自大脑后动脉发出海马动脉、颞下前动脉和颞下后动脉供应颞底.静脉均引流入基底静脉.3例星形细胞瘤患者施行小脑上经小脑幕入路颞底内侧区后部肿瘤切除术,完全切除肿瘤,疗效满意.结论 小脑上经小脑幕入路手术能够较好显露颞底内侧区后部解剖结构,熟练掌握该人路的解部学知识有助于处理颞底内侧区后部病变.     

幕上下锁孔入路的显微解剖研究

目的探讨岩斜区幕上下锁孔入路显微解剖,为岩斜区手术入路提供解剖学依据。方法在10例国人成人头颅湿标本上,在手术显微镜下观察,测量幕上下锁孔入路的重要显微结构;对手术前后共10例标本进行3D-CT颅骨重建:并对重要结构进行测量。结果通过幕上下锁孔入路,可涉及的重要解剖区域包括三叉神经、面听神经、岩骨内部结构、脑干腹侧间隙等,重要参数包括岩骨嵴磨除范围。结论岩斜区幕上下锁孔入路是手术治疗岩斜区肿瘤的灵活运用的手术入路。     

乙状窦前和乙状窦后入路微创显露膝状神经节的虚拟现实比较

目的：通过虚拟现实技术比较乙状窦前和乙状窦后入路微创显露膝状神经节的显微解剖特征。方法对15例尸体头颅行M RI和C T扫描,将影像数据输入虚拟现实系统,构建颞骨三维解剖模型,在颅盖和颅底选择骨性标志点勾勒乙状窦前和乙状窦后入路显露膝状神经节的手术路径。观察两种路径的解剖结构空间形态和顺序,测量解剖组织体积,采用配对 t检验进行比较分析。结果乙状窦前入路由乳突开始磨除岩骨,避开乙状窦和颈静脉球,经过面神经垂直段、听骨链、迷路,到达膝状神经节时,显露面神经。乙状窦后入路由横窦下方开颅,经过小脑半球,到达内听道时磨除岩骨,经过面听神经复合体,到达膝状神经节,路径中包含听骨链和迷路。手术路径和迷路体积测量：乙状窦后入路＞乙状窦前入路;面听神经复合体和听骨链体积：乙状窦前入路＞乙状窦后入路,差异均有统计学意义（P ＜0．05）。乙状窦后入路中小脑半球体积为（462．72±20．87）mm3,乙状窦前入路不包含小脑半球。两种路径中骨性结构（不包含听骨链）体积的差异无统计学意义（P＞0．05）。结论在磨除岩骨显露膝状神经节的路径中,乙状窦前入路有助于减少迷路损伤范围,乙状窦后入路有助于减少听骨链损伤范围并显露面听神经复合体。     

远外侧枕髁后锁孔手术入路设计与显微解剖学实验研究

目的将微创锁孔手术理念融入远外侧入路,探讨枕髁后锁孔手术的可行性。方法于8具尸头乳突后作纵向“S”型、约7 cm长头皮切口,上缘起自乳突中点向后2 cm处,下界至C2水平。分层翻转枕下肌群,显露枕骨远外侧,在枕髁后做一直径约3 cm的骨窗,牵开小脑半球,显微镜下观察所显露的解剖结构。结果通过调整头位及显微镜角度,经枕髁后锁孔入路可显露同侧椎动脉、小脑后下动脉、小脑前下动脉、面听神经、后组脑神经、舌下神经、延髓腹外侧等结构。结论枕髁后锁孔入路可很好地显露上述结构,应用现代显微外科技术,可在不磨除枕髁的情况下进行椎动脉瘤、小脑后下动脉瘤、较小体积的舌下神经鞘瘤、延髓腹外侧肿瘤等手术。     

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.     

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.