现代听神经瘤保留听力手术与术中听神经功能监测

显微神经外科手术是听神经瘤（Acoustic neuroma,AN）的首选治疗方法。完全切除肿瘤、保留最佳面神经功能甚至保留听神经功能,是现代听神经瘤外科治疗的方向。随着显微神经外科、影像学及术中神经电生理监测技术的发展,听神经瘤患者听力保留率显著增加[1,3,7,17]。     

锁孔入路显微血管减压术治疗三叉神经痛的手术配合

三叉神经痛是一种在三叉神经分布区域内出现反复发作的阵发性剧痛，微血管压迫是三叉神经痛的主要原因。随着神经疾病病因学研究的进展及显微神经外科手术技术和微创理念的发展，三叉神经微血管减压术（M VD ）成为目前治疗三叉神经痛的主要方法［1］，也是唯一一种针对病因治疗的手段，而且又能保留神经功能［2］。现将M VD的手术配合及体会报道如下。     

无症状性脑膜瘤

随着影像学的发展,近年来无症状性脑膜瘤的发现率不断增加。本病多为良性肿瘤,生长缓慢,肿瘤生长速率低、倍增时间长。临床上主张采用多种方法治疗。首先应严密随访观察,应用MRI/CT每3~6个月进行一次颅脑扫描,注意肿瘤体积是否增大、影象强度的变化。依据肿瘤的增长速率、倍增时间,选择好时机争取在出现临床症状之前及时手术切除;对位于颅底直径小于3.0cm的肿瘤可首选γ-刀治疗;手术切除后残留或复发的肿瘤γ-刀治疗是很好的辅助治疗手段。年老体弱、合并其他疾病不能耐受手术的病例γ-刀治疗是理想的选择。γ-刀集聚高剂量射线照射肿瘤,对周围正常组织的损伤轻微,是精确、安全、有效的治疗方法。     

听神经瘤听力保留的研究进展

近年来随着神经影像学、神经电生理以及显微技术的发展,听神经瘤的治疗重点已从延长患者生命逐步转移到相关神经功能的保留,其中,听力保留成为继肿瘤全切除和面神经功能保留之后的现代听神经瘤外科治疗的又一研究重点。本文综述了听神经瘤听力损害及听力保留的概念、听力保留的有关影响因素、术中监测技术的研究进展和不同治疗方式的适应症及优缺点,并提出目前听神经瘤听力保留治疗存在的问题及展望。     

胶质瘤X-刀治疗后放射性坏死貌似肿瘤复发

目的 探讨X-刀治疗胶质瘤后放射性坏死貌似肿瘤复发的临床表现与影像学特点。方法回顾性分析7例因胶质瘤而首选X-刀治疗后疑似肿瘤复发再行手术治疗，病理结果证实为放射性坏死病人的临床表现与影像学特点。结果7例病人均在X-刀治疗后半年内．平均4．3个月，出现颅内压增高症状或原有症状的加重，影像学(CT、MRI)特征表现为病灶范围扩大，病灶无明显增强及占位表现；手术切除病灶后病理报告为坏死组织，未发现肿瘤细胞。结论X-刀治疗半年内出现的颅内压(ICP)增高症状或原有症状加重可能为延迟性放射性坏死，极易与胶质瘤复发混淆，应根据影像学特点加以鉴别，鉴别困难时，应先行保守治疗．无效时方可手术治疗，以减少病人不必要的神经损害和经济负担。     

巨大不规则型垂体腺瘤的显微外科手术治疗

目的探讨巨大不规则型垂体腺瘤不同手术入路选择的临床意义，总结出针对不同生长形态肿瘤的较好的手术入路和治疗方案。方法根据66例巨大不规则型垂体腺瘤的临床病史特点和CT、MRI等影像学表现，详细制定手术治疗方案，并按照肿瘤的不同生长形态选择合适的手术入路，部分术中采用神经导航和神经内窥镜辅助技术。结果本组病例分别采用6种不同手术方案，全切除10例，次全切除51例，大部切除1例，部分切除4例。手术死亡4例。结论术前应根据病史和影像学资料、肿瘤的生长形态以及累及的解剖腔隙，选择合理的手术入路和治疗方案，避免对鞍区重要解剖结构的损伤，才能取得较好的临床疗效。神经导航和神经内窥镜辅助技术有助于提高肿瘤的切除率。     

听神经瘤显微外科治疗

随着神经影像技术、神经电生理监测技术和现代显微神经外科技术的不断发展,听神经瘤的手术治疗发生了根本性的变化,即不仅可以全切除肿瘤,而且还可以保留面神经甚至听神经功能。听神经瘤的早期诊断对提高听神经瘤的面、听神经功能保留非常重要。本文结合作者本人的手术经验和文献资料,分析听神经瘤的显微操作技术和面、听神经保留的方法和技巧,总结当前听神经瘤的显微外科治疗现状。作者指出:显微外科手术是治疗听神经瘤的有效方法,肿瘤的全切除不能以牺牲病人的神经功能为代价,要最大限度地保留神经功能,以提高病人的术后生存质量。     

岩斜区脑膜瘤的显微外科治疗

目的通过对234例岩斜区脑膜瘤显微外科治疗的分析,探讨岩斜区脑膜瘤的显微手术入路与治疗效果。方法总结234例岩斜区脑膜瘤的临床表现、神经影像学特征、显微手术入路及方法和术后处理。结果肿瘤全切除及次全切除192例(82.0%),死亡4例(1.7%)。结论岩斜区脑膜瘤的治疗采用手术治疗,根据肿瘤在斜坡的不同部位采用相应的手术入路,经岩骨乙状窦前入路目前是该部位肿瘤的首选手术入路,早期诊断、早期治疗,减少手术并发症,以达到治愈的目的。     

颅脑肿瘤治疗的新进展

颅脑肿瘤治疗的进展是近年来临床神经外科发展的重头戏之一。随着脑干肿瘤等显微手术疗效的大大提高，颅内肿瘤手术的“禁区”已经不复存在。高精技术在临床上的应用获得成功使颅内肿瘤总的手术死亡率有了较大幅度下降，肿瘤的基础研究也取得了令人鼓舞的进展，基因治疗已应用于临床。颅内肿瘤治疗的光明前景正在鼓舞人心。现就某些有关问题谈一点情况。一、以大骨瓣开颅、充分暴露为基本特征的颅底外科走向成熟颅底解剖结构复杂、聚集了重要的血管、神经组织。显微外科技术的提高、神经影像学和神经放射学的发展推动了包括脑干肿瘤在内的颅…     

小儿松果体区肿瘤外科治疗策略

松果体区肿瘤是指来源于松果体及其临近组织结构的肿瘤,临床较罕见,但儿童发病率较高,占儿童颅内肿瘤的3％～11％。其组织病理类型复杂多样,良性肿瘤占1／3左右。目前对于各种类型松果体区肿瘤的治疗尚有争议,但根据准确的组织病理结果来选择最佳治疗方法的观点已被临床公认。在现代显微神经外科发展以前,大多数作者主张保守治疗,主要治疗策略为脑室分流后进行分次放疗。随着神经影像学、显微神经外科技术、神经麻醉和术后ICU监护的发展,     

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.