颅内软骨瘤的诊断与治疗(附七例报道)

目的探讨颅内软骨瘤的临床特点及诊断与治疗原则。方法对1979-2004年我科收治的7例颅内软骨瘤患者的临床特点、影像表现及治疗方法与预后情况进行分析。结果7例颅内软骨瘤占本科同期收治的6303例颅内肿瘤的0．11％。本病多见于青壮年，病程2个月至10年。6例肿瘤位于颅底部中线旁硬膜外，并出现1例罕见的额顶部软骨瘤。6例颅底部肿瘤见骨质破坏与钙化，CT呈不均匀混杂密度影，2例有轻度强化；3例MRI显示T1WI呈低或混杂信号、T2WI呈高及混杂信号。肿瘤质地较硬。与重要神经血管相邻．不易全切除。2例病理报告肿瘤生长活跃，均复发。结论颅内软骨瘤发病率低，病程长，多见于颅底部中线旁，多见骨质破坏与钙化。诊断时需要与脑膜瘤、颅咽管瘤及脊索瘤相鉴别。颅内软骨瘤的治疗原则为手术切除，颅底部软骨瘤不易全切除。     

颅内血管外皮细胞瘤的诊断及治疗(附14例分析)

目的总结颅内血管外皮细胞瘤(HPC)的诊治经验。方法回顾性分析14例颅内HPC病人的临床资料和影像学表现。结果肿瘤全切除11例,次全切除3例。随访13例,随访时间5～62个月,恢复良好10例,死亡3例。颅内HPC的CT影像特点为平扫显示肿瘤呈等、高密度,未见瘤内钙化、邻近颅骨骨质增生及脑膜尾征等常见征象;MRI影像特点为T1WI显示肿瘤呈等、低混杂信号,T2WI显示肿瘤呈等或等、高混杂信号;增强后所有肿瘤明显强化,肿瘤多呈分叶状,窄基底附着硬膜,有丰富的血管流空,无脑膜尾征,无颅骨增生和钙化。结论颅内HPC具有比较典型的CT和MRI影像学特点,有助于临床诊断。颅内HPC首选手术治疗,术后可辅以放射治疗。     

微囊型脑膜瘤的MRI表现及临床病理对照研究

目的探讨微囊型脑膜瘤的MRI表现及其诊断价值,并与病理相对照。方法回顾性分析12例经病理证实的微囊型脑膜瘤影像学资料及病理资料。结果额叶6例(左4例,右2例),颞叶2例,顶叶大脑镰旁2例,右侧桥脑小脑角区1例,鞍区1例;12例中9例平扫T1WI呈低信号,T2WI呈明显高信号,增强后病变呈明显不均匀强化;3例平扫时T1WI呈不均匀等低信号,T2WI呈不均匀等高混杂信号,增强后病变呈明显不均匀强化;12例病变中5例可见脑膜尾征;10例可见中、重度瘤周水肿;镜下组织中见瘤细胞排列疏松,呈微囊状。结论微囊型脑膜瘤是颅内少见肿瘤,MRI表现有一定特点:T1WI呈低信号,T2WI呈明亮高信号,瘤周水肿明显,增强后呈明显强化,MRI有助于对其诊断和鉴别诊断。     

恶性脑膜瘤CT与MRI表现

目的分析恶性脑膜瘤CT与MRI影像学表现,以提高其术前诊断准确率。方法回顾性分析18例经手术病理证实的恶性脑膜瘤CT与MRI影像学表现。结果 18例肿瘤中,大脑镰旁5例,大脑凸面4例,海绵窦旁3例,鞍上2例,鞍旁2例,小脑半球2例;边缘规整者4例,边缘分叶状者14例,肿瘤边缘清晰者2例,边缘模糊者16例;CT密度、T2WI信号不均匀者15例,内部可见囊变、坏死、出血。肿瘤强化显著,15例表现为不均匀强化,3例均匀强化,13例表现为短、粗不规则硬膜尾征;轻度水肿8例,中度水肿5例,重度水肿5例;临近颅骨破坏5例,2例形成软组织肿块并突向颅外,6例颅骨增生、硬化。结论恶性脑膜瘤具有特殊的影像学特征,正确分析其表现,有助于提高其术前诊断率。     

颅内血管外皮细胞瘤的MRI特征

目的探讨颅内血管外皮细胞瘤(hemangiopericytoma,HPC)的MRI特征。方法回顾性分析13例经手术病理证实的HPC患者的MRI征象。结果肿瘤位于幕上额顶部大脑镰旁4例,额颞部3例,颞枕部2例;幕下小脑幕旁2例,小脑凸面1例。8例呈分叶状,2例形态不规则,T_1WI呈不均匀等、低信号,T_2WI呈混杂信号,其中8例有囊变坏死,5例见流空血管,4例伴轻度水肿,3例伴邻近骨质破坏,增强呈不均匀明显强化。3例呈类圆形,T_1WI呈均匀等、稍高信号,T_2WI呈均匀等信号,增强呈均匀明显强化。5例与硬脑膜以宽基底相连,8例以窄基底相连,5例伴"脑膜尾征"。12例DWI呈稍低或等信号,1例呈混杂信号。结论 HPC具有较为特征性的发病部位及MRI特点,综合分析MRI特征,能够在术前作出正确诊断。     

颅内原发黑色素瘤的CT和MRI诊断

目的 探讨颅内黑色素瘤的CT和MRI影像学表现特征,进一步提高对本病的认识.方法 对4例颅内黑色素瘤的CT和MRI表现,结合文献进行回顾性分析,全部病例均CT、MRI平扫,其中3例CT进行增强,2例MRI进行增强.结果 单发肿瘤和多发肿瘤各2例,CT表现为类圆形高密度影3例,低密度影1例;4例MRI检查,肿瘤呈短T1短T2信号2例,短T1长T2信号1例, 等T1短T2信号1例,肿瘤信号不均匀,边缘清楚,增强后肿瘤呈均匀性强化.结论 肿瘤内特征性的短T1短T2信号对术前确诊具有决定意义,是颅内黑色素瘤的最佳影像学检查方法 ,而CT高密度影应与出血性脑膜瘤等相鉴别.     

大脑镰旁脑膜瘤的MRI诊断和显微手术治疗

目的探讨大脑镰旁脑膜瘤的MRI特点和显微手术技巧。方法回顾性分析24例大脑镰旁脑膜瘤的诊断和治疗。结果24例MRI检查均有不同程度瘤周水肿,T1加权像呈稍低或等密度信号,T2加权像呈稍高或等密度信号,增强扫描肿瘤明显强化,11例有“硬膜尾征”。3例颅骨侵犯。所有患者均采用显微手术治疗,SimpsonⅠ级切除19例,Ⅱ级切除5例。随访10个月至8年,无肿瘤复发。结论MRI是目前诊断大脑镰旁脑膜瘤首选的方法,对手术入路的选择及术中并发症的预防有指导意义。显微手术明显提高大脑镰旁脑膜瘤的全切除率,减少残死率。     

鞍上肿瘤的MRI诊断(附23例报告)

目的评价MRI对鞍上肿瘤的诊断价值。方法回顾性分析我院23例鞍上肿瘤患者临床及头颅MRI资料，其中颅咽管瘤8例，脑膜瘤5例，室管膜瘤和生殖细胞瘤各3例，毛细胞星形细胞瘤和表皮样囊肿各2例。结果颅咽管瘤边界光整，肿瘤以囊性或囊性成分为主；囊性部分呈短T1、长T2信号5例，长T1、长T2信号2例，等T1、长T2信号1例；增强扫描肿瘤实质部分显著强化。5例脑膜瘤4例起源于鞍结节，1例起源于前床突，肿瘤边界光整：平扫呈等T1、稍长T2信号；增强后均匀显著强化，可见“脑膜尾征”。室管膜瘤形态极不规则，2例侵犯额叶，1例侵犯丘脑；肿瘤呈长T1、长T2信号；1例见有团块状钙化（T2WI呈低信号）；增强扫描显著强化。生殖细胞瘤形态较规则，肿瘤沿垂体柄向鞍内生长，致垂体柄增粗，T1、WI垂体后叶高信号消失：1例表现颅内多发病灶；2例平扫呈长T1、稍长T2信号，1例呈长T1、长T2信号，瘤内有较多数量小圆形囊变区；增强扫描肿瘤强化明显。2例毛细胞星形细胞瘤呈浅分叶状，肿瘤沿视路生长，1例肿瘤跨越前、中、后颅窝，1例显示一侧视神经增粗：平扫肿瘤呈长T1、长T2信号，边缘见有多个新月状囊变区；增强扫描肿瘤显著强化。2例表皮样囊肿形态不规则，肿瘤向后蔓延生长至环池和桥前池：呈长T1、长T2信号，内见线样间隔；增强后无强化。结论不同类型鞍上肿瘤MRI表现不同．MRI对鞍上肿瘤诊断具有重要价值。     

颅内室管膜下瘤磁共振特征与鉴别诊断

目的探讨颅内室管膜下瘤磁共振影像学表现,以期提高对该病的影像学认识水平,有利于术前的诊断。方法回顾性分析9例(我院及外院)经手术病理证实的室管膜下瘤的磁共振影像学资料,并与脑室内其他肿瘤进行鉴别诊断。结果肿瘤位于侧脑室5例,透明隔区2例,三角区2例。瘤体主要呈椭圆形6例,另外3例呈分叶样不规则形。瘤体边界清楚,大小约1.4~4.4 cm。T1WI、T2WI呈等信号4例,3例呈等长T1等长T2信号,2例T1像见短信号,DWI呈略高信号,T2FLAIR病灶呈较高信号。对比剂增强后肿瘤3例无强化,4例轻度强化,2例中等强化。5例瘤体内见小类圆形囊状改变,2例患者同时伴有梗阻性脑积水。结论颅内室管膜下瘤好发于脑室系统内,MRI平扫T2小囊性变及增强后不强化或轻度强化为其典型表现,接近孟氏孔区病灶可较大,增强后可中等强化,本病易与脑室内其他肿瘤相鉴别,术前能够较为准确地诊断。     

颅内生殖细胞瘤的CT和MRI表现

目的探讨颅内生殖细胞瘤的CT和MRI影像特征。方法回顾性分析18例经病理或放射治疗证实的颅内生殖细胞瘤的CT和MRI表现。结果 18例肿瘤中,9例肿瘤位于松果体区,6例位于鞍区,3例位于基底节区及丘脑。松果体区肿瘤在MRI呈长T1、等或长T2信号,边缘光滑,出血少见;CT呈均匀等密度或稍高密度,松果体钙化常被肿瘤包埋,增强扫描时肿瘤均匀显著强化。鞍区肿瘤MRI表现为垂体柄增粗,垂体后叶正常短T1信号消失,肿瘤在T1WI像呈等信号,T2WI像上信号可呈等或高信号;CT图像见肿瘤实体部分呈高密度,增强扫描时明显强化。基底节区及丘脑肿瘤瘤体较大,信号及密度不均匀,边缘欠清晰,出血多见,增强扫捕呈不均匀强化。结论颅内生殖细胞瘤的影像表现具有一定特征,结合临床表现可进一步提高诊断正确率。     

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.