中枢神经系统原发性淋巴瘤影像学特征与病理分析

目的探讨中枢神经系统原发性淋巴瘤影像学特征并进行病理分析。方法回顾性分析我院收治的23例中枢神经系统原发性淋巴瘤患者的CT以及MRI表现。结果中枢神经系统原发性淋巴瘤在进行CT以及MRI检查的过程中发现肿瘤多侵入额叶以及颞叶,病理学方面B细胞占据大部分。23例患者中单发病灶16例,多发病灶7例,病灶共39个,其中额叶10个,顶叶6个,枕叶3个,颞叶6个,基底节区5个,胼胝体3个,下丘脑2个,小脑4个,CT为低等密度,T1WI是稍低信号,T2WI为低等信号,中等水肿,增强造影后明显出现均匀强化。造影显示一些病灶位于基底节、胼胝体以及脑室的周围,容易误诊为多发性脑梗死或脱髓鞘。结论绝大多数中枢神经系统原发性淋巴瘤有明显的影像学特征,可以作出正确诊断并为临床治疗提供依据。     

原发性中枢神经系统淋巴瘤非典型MRI影像学表现

目的总结原发性中枢神经系统淋巴瘤(PCNSL)非典型MRI影像学表现,以提高对非典型PCNSL影像诊断的正确率。方法回顾性分析经穿刺或手术病理证实的25例原发性中枢神经系统淋巴瘤的MRI影像学表现,包括非典型的生长部位,非特异的MRI表现和强化方式。结果 25例中单发病灶者16例,多发病灶9例,病灶数共38个。不典型发生部位可见于鞍上、脑干、小脑半球和小脑蚓部、侧脑室、三脑室和第四脑室等等。病灶形态大小不一,表现形式多种多样,可呈类圆形、不规则形,团块状、结节状、斑片状、灶状或散在分布。1例病灶侵及邻近脑膜,出现"脑膜尾征"。20例在T1WI呈稍低或等信号,T2WI呈等或稍高信号,5例T1WI、T2WI呈混杂信号。7例呈实性均质强化,6例呈结节状强化,3例呈斑片状强化,2例呈条纹状强化,2例呈环形强化,1例呈弥漫肿胀伴轻度强化,3例多发病灶多种强化方式并存。5例DWI呈均质高信号,6例呈不均匀稍高信号,4例呈中等信号。MRS检查4例出现较明显的Lip峰。结论对于发生在非典型生长部位、影像学表现非特异性的,以及颅内多发病灶的和侵犯脑膜的中枢神经系统淋巴瘤,术前诊断较为困难,需引起高度重视。     

原发性中枢神经系统淋巴瘤发病不同阶段影像学和病理学特点

目的回顾1例弥漫性大B细胞淋巴瘤不同发病阶段的临床、影像学和病理学特点,并分析其可能的发生机制。方法与结果女性患者,29岁,汉族。首次发病以视物模糊、视野缺损为主要临床表现;头部MRI显示右侧顶枕叶皮质下斑片状T1WI稍低信号、T2WI和FLAIR成像高信号,无明显占位效应,增强扫描病灶呈点状强化;激素冲击治疗后病灶逐渐消失。再次发病以头痛、呕吐和左侧肢体瘫痪为主要临床表现;头部MRI显示右侧额顶叶大片状T1WI低信号、T2WI和FLAIR成像高信号,占位效应明显,增强扫描病灶呈实性强化。于手术显微镜下全切除肿瘤。组织学形态观察,肿瘤细胞体积较大,胞质较丰富,胞核大小形态不一,核分裂象易见,片状坏死,间质小血管增生。免疫组织化学染色,肿瘤细胞胞膜CD20、胞核配对盒基因5和多发性骨髓瘤癌基因1呈阳性,少数肿瘤细胞胞膜CD10和CD30、胞核周期蛋白D1呈阳性,CD3、间变性淋巴瘤激酶和胶质纤维酸性蛋白呈阴性,Ki-67抗原标记指数为80%。EBER原位杂交检测EB病毒编码m RNA呈阴性。肿瘤组织呈明显噬血管特性,围绕并侵犯血管壁,最终病理诊断为弥漫性大B细胞淋巴瘤。结论原发性中枢神经系统淋巴瘤的影像学表现多样,呈实性占位性或浸润性病变,是肿瘤发病不同阶段的不同表现,与肿瘤嗜血管特性有关。     

免疫正常人原发性脑淋巴瘤的MR表现

目的 探讨免疫正常人原发性脑淋巴瘤的MR表现及其诊断价值. 方法 回顾性分析经手术病理证实的15例免疫正常人脑淋巴瘤的MR资料,患者均行常规MR平扫和增强检查. 结果 15例患者共有18个病灶,14个在幕上,4个在幕下.7个病灶有明显的坏死囊变或出血.2例出现柔脑膜转移.在MR的T1WI、T2WI图像上15个病灶实质呈等信号,增强后所有病灶实质呈明显均匀强化,17个病灶表现轻中度占位效应. 结论 免疫正常人原发性脑淋巴瘤幕上多见,MR的T1WI、T2WI图像上肿瘤实质呈等信号,增强后明显均匀强化,有轻度中度占位效应,具有一定特征性.     

中枢神经系统淋巴瘤二例

目的探讨中枢神经系统淋巴瘤的临床、脑脊液细胞学、影像学和病理学。方法对两例中枢神经系统淋巴瘤患者进行腰椎穿刺术,行脑脊液测压、常规、生化、细胞学检查及磁共振(MRI)扫描。结果例1为原发性中枢神经系统非霍奇金淋巴瘤脑病变,例2为继发性中枢神经系统非霍奇金淋巴瘤脊髓病变。例1患者临床表现主要为肢体无力、记忆力下降及脑神经损伤。脑脊液压力125mm H2O,氯化物130.0mmol·L-1,葡萄糖4.97 mmol·L-1,蛋白0.46g·L-1。头颅MRI T1WI呈低信号,T2WI呈高信号,增强后强化。病理切片可见少量小圆形肿瘤细胞,免疫组化显示为CD20阳性。例2患者临床主要表现为肢体无力,脑脊液压力180mm H2O,氯化物124.6mmol·L-1,葡萄糖3.77 mmol·L-1,蛋白1.73g·L-1。椎体MRI示T1WI低信号,T2WI呈高信号,增强后均匀强化。病理诊断为弥漫性大B细胞淋巴瘤。结论中枢神经系统淋巴瘤的临床表现和其侵犯部位有关,脑脊液中可找到肿瘤细胞,MRI表现为低T1WI信号,高T2WI信号,增强后强化。病理多显示为B细胞来源的淋巴瘤。     

原发性中枢神经系统淋巴瘤35例临床分析

目的原发性中枢神经系统淋巴瘤发病率较低,报道较少,本文探讨其诊断及治疗特点。方法通过回顾性分析35例病理诊断为中枢神经系统淋巴瘤的病例,根据其临床表现、影像学表现、病理以及治疗,总结其诊疗的特点。结果原发性中枢神经系统淋巴瘤多以颅内压升高症状起病,伴共济失调症状,影像学MRI稍长或等T1信号、稍长或等T2信号,增强后呈均匀一致强化,可形成"缺口征"、"尖角征"、"握拳征"特征性表现,磁共振弥散加权成像(DWI)多呈均匀高信号,磁共振波谱分析(MRS)表现为氮-乙酰天门冬氨酸(NAA)中度降低,胆碱(Cho)升高,肌酸(Cr)轻度降低,可出现高大脂质(Lip)峰,肿瘤多表达B细胞或T细胞标记物,肿瘤增殖抗原(Ki67)阳性率多为30%~95%。治疗目前多以手术治疗明确病理,解除患者颅内高压症状,术后行以大剂量甲氨蝶呤为中心的化疗,辅以放疗。结论原发性中枢神经系统淋巴瘤临床表现难以与其他肿瘤鉴别,影像学表现具有一定特定性,病理学与免疫组化有其独特的表现,治疗目前多以化疗为中心的综合治疗为主。     

小脑富脂质髓母细胞瘤临床病理学特征:病例报告及文献综述

目的 探讨小脑富脂质髓母细胞瘤临床病理学特征.方法 对一例小脑富脂质髓母细胞瘤患临临床表现、影像学特点,以及组织病理学和免疫组织化学特征进行回顾性分析,并复习相关文献.结果 男性患者,26岁.临床表现为反复头痛,伴头晕、恶心、呕吐.MRI显示病灶填允第四脑室,T1WI呈均匀低信号、T2WI呈不均匀高信号,增强T1WI扫捕病灶晕明显均匀强化,边界清晰.手术后光学显微镜下观察肿瘤细胞弥漫增生,大小一致,胞质淡染,呈弱酸性或嗜双色,核圆形或卵圆形,染色质细腻,核仁可见,核分裂象易见;间质中含有丰富的薄壁血管;富于脂质的细胞呈灶性分布.免疫组织化学染色肿瘤细胞CD56和突触素弥漫阳性,局灶表达神经微丝,弱表达少突胶质细胞系转录凶子-2;不表达巢蛋白、神经元核抗原、S-100蛋白、胶质纤维酸性蛋白和上皮膜抗原;TP53染色阳性(约10%).Ki-67抗原标记指数约为40%.结论 发生于小脑的富脂质髓母细胞瘤为临床罕见的中枢神经系统肿瘤,影像学呈现发生于小脑蚓部向第四脑室生长的占位性病变;病理学表现肿瘤细胞由高度密集的一致圆形细胞组成,具有灶性脂肪样细胞分化.应注意与小脑脂肪神经细胞瘤和室管膜瘤等相鉴别.     

原发性中枢神经系统淋巴瘤MRI与DWI及1HRS表现

目的探讨原发性中枢神经系统淋巴瘤的常规MRI与DWI及1HRS表现。方法回顾性分析我院经手术病理证实的20例原发性中枢神经系统淋巴瘤临床及影像学资料。结果男11例,女9例,年龄21～70岁,平均54岁,20例患者共检出27个病灶,表现如下：（1）常规MRIT1wI呈低、等信号,T2wI呈低、等、略高信号,边缘清晰,单发或多发;（2）增强扫描病灶呈团块状、结节状强化,可见“缺口征”、“尖角征”等特异性征象;（3）肿瘤实质区DWI呈均匀高信号;（4）肿瘤实质区’H—MRS扫描Cho峰升高,NAA及cr峰降低,并见Lip峰升高。结论原发性中枢神经系统淋巴瘤常规MRI与DWI及。H—MRS表现具有特征性,对临床诊断及鉴别诊断具有指导意义。     

原发性中枢神经系统淋巴瘤的影像学变化及临床(附1例报告及文献复习)

目的分析原发性中枢神经系统淋巴瘤MRI的动态变化及临床特点。方法对1例原发性中枢神经系统淋巴瘤患者的MRI变化、临床表现、病检结果,结合相关文献进行讨论分析。结果患者临床上反复发作,影像学上表现不典型,多在基底节、胼胝体和脑室周围,常误诊为多发性脑梗死或脱髓鞘疾病。结论原发中枢神经系统淋巴瘤临床上和影像学上酷似脱髓鞘病,行CT引导下立体定向穿刺或病灶组织活检有助于确诊。     

中枢神经系统孤立性纤维性肿瘤2例临床病理分析

目的 总结中枢神经系统孤立性纤维性肿瘤的影像学表现、病理学特征及其诊断意义.方法 回顾性分析中枢神经系统孤立性纤维性肿瘤病人2例的临床表现、影像学特点、病理学表现、手术措施和治疗效果并随访.结果 患者表现占位病变和局部压迫症状.MR表现T1WI等信号,T2WI低信号,增强肿瘤不均匀强化.行肿瘤全切除术2例.病理检查见肿瘤由短梭形细胞无序散在胶原胶质中,细胞密集区域和稀疏区域相间,血管丰富区域呈血管外皮瘤样结构. CD34(+),Vim(+),EMA(-),S-100(-).患者随访至今未见复发.结论 孤立性纤维性肿瘤发病率低,临床易误诊.MR检查T2像的"黑白相间征"及显著不均匀增强的特点有助于诊断,病理检查可明确诊断.     

Diagnostic Difficulties and Treatment Implications

Summary: Differentiation between types of epileptic seizures has been aided in recent years by the introduction of intensive neurodiagnostic techniques and the development of increasingly detailed classification systems. Paradoxically, these developments have not simplified the task of matching the appropriate antiepileptic drug to a particular seizure type. It is reasonable to assume that anticonvulsant drugs will have different effects on different types of seizures, but faulty, circular reasoning can enter the picture if one also assumes that responses of seizures to different drugs signify different seizure types. There are several examples of differential diagnoses that can fall prey to this problem, including the diagnosis between partial seizures with secondary generalization and generalized tonic-clonic seizures, and the diagnosis between complex partial seizures and absence seizures with automatisms, among others. Considerations of etiology in future classification systems can further complicate the problem: should one then choose an anticonvulsant drug on the basis of individual seizure type or on the basis of the type of epilepsy? Ramifications of this issue extend even to the drug approval process. Official sanction is not given for use of a drug for a seizure type not included in the original efficacy studies, even if later scientific evidence shows that seizure type to be related to a type that is included. New trials must be undertaken. These problems arise from how we choose to classify seizures.     

Cognitive Dysfunction Associated with Antiepileptic Drug Therapy

Summary: Epilepsy is frequently associated with cognitive dysfunction. However, the reasons for this correlation are unclear. Possible influential factors include patient age; duration, frequency, etiology, and type of seizures; hereditary factors; psychosocial issues; and antiepileptic drug (AED) therapy. Whereas many of these factors are beyond the physician's control, AED therapy is one element that can be addressed in treatment decisions by recognizing the potential cognitive effects of particular AEDs. For example, phenobarbital impairs memory and concentration; phenytoin affects attention, problem solving ability, and performance of visuomotor tasks. In contrast, carbamazepine may affect concentration, while valproate would appear to have minimal effects on cognition. Moreover, cognitive effects of AEDs are amplified with coadministration of multiple anticonvulsants (polytherapy). A review of studies on the cognitive effects of monotherapy with AEDs, as opposed to those of polytherapy, provides evidence that drug-related cognitive dysfunction can be reversed if patients are switched to a simpler therapeutic regimen. Future research should be directed toward developing reliable measures for assessing and monitoring cognition, and understanding the particular cognitive side effects of each AED. Physicians also need to revise their opinions about which side effects are "tolerable" for epileptic patients.     

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.     

Carbamazepine Efficacy in Adults With Partial and Generalized Tonic-Clonic Seizures

Summary: Carbamazepine and phenytoin are drugs of choice in initial monotherapy for adult partial and secondarily generalized tonic-clonic seizures. These designations reflect the results of the Veterans Administration Epilepsy Cooperative Study Group of 1985. An earlier comparative study of carbamazepine and phenytoin by Ramsay and associates found both drugs equally effective in controlling new-onset seizures. Among the advantages of carbamazepine is that it causes relatively few cognitive and dysmorphic side effects. Its disadvantages are its unavailability in parenteral formulation and its metabolic autoinduction. The latter must be compensated for by planned dosage increases to maintain therapeutic plasma steady-state levels during the first 2 or 3 months of treatment. Carbamazepine is judged a drug of choice in the treatment of these secondarily generalized tonic-clonic seizures, and the drug of choice in children, adolescents, and women susceptible to the dysmorphic side effects associated with other anticonvulsant agents.     

Etiologic and Preventive Aspects of Epilepsy in the Child–Bridging the Gap Between Laboratory and Clinic

Summary: Four broad categories of basic phenomena are pertinent to developing ways to prevent epilepsy. These include mechanisms of epileptogenesis, ictal initiation and temporary entrainment by the seizure discharge of normally functioning brain, seizure propagation, and control mechanisms that function both to restrain the cascade of epileptic events culminating in a seizure and to arrest the epileptic event and restore the interictal state. In newborns and children, hypoxia-ischemia is a major factor leading to epileptogenesis, and several schemes are proposed to classify, quantify, and prevent hypoxic-ischemic encephalopathy. Control mechanisms must be better understood in order to develop prophylactic recommendations for epilepsy, and an experimental model of "kindling antagonism" may increase our understanding of these. Programs of prevention of seizures in children will evolve only if basic researchers and clinicians work productively together to develop an adequate understanding of factors important in epileptogenesis and antiepileptogenic control mechanisms.     

Predisposing and Causative Factors in Childhood Epilepsy

Summary: We review information from large studies of defined populations, examining the role of known factors and especially of prenatal and perinatal factors in contributing to nonfebrile seizure disorders of early childhood. We depend especially, but not exclusively, on the recently completed analyses from the Collaborative Perinatal Project of the National Institute of Neurological and Communicative Disorders and Stroke, the NCPP. About 4% of children in the NCPP who had at least one non-febrile nonsymptomatic seizure by the age of 7 years had a previous seizure during acute neurologic illness, such as meningitis or during the acute illness after trauma. Many such seizures should potentially be preventable. Of children with seizures, 10% had had a neonatal seizure and 13% had had a febrile seizure. Among the hundreds of prenatal and perinatal factors explored as predictors of childhood seizure disorders, the principal predictors identified were congenital malformations of the fetus, cerebral and noncerebral; family history of certain neurologic disorders; and neonatal seizures. In agreement with the British National Child Development Study, labor and delivery factors in the NCPP appeared to contribute very little to childhood seizure disorders. Maldevelopment, rather than damage at birth to an initially intact nervous system, appeared to be the more common mechanism. Most seizure disorders of early childhood remained unexplained by the large set of prenatal and perinatal characteristics examined.     

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.     

Treatment Considerations in Anticonvulsant Monotherapy

Summary: The long-standing practice of polypharmacy in treating epilepsy is giving way to use of monotherapy. Monotherapy can improve seizure control as well as reduce the risk of serious idiosyncratic reactions, dose-related side effects, and complex drug interactions. Monotherapy also offers improved compliance and cost-effectiveness. The basis of monotherapy is accurate diagnosis and assessment of the patient's seizure type(s), followed by selection of a single appropriate anticonvulsant drug. Many patients currently treated with multiple anticonvulsants can be successfully converted to monotherapy with a carefully monitored program in which troublesome and redundant drugs are gradually withdrawn from the therapeutic regimen.     

Anticonvulsant Drugs and Cognitive Function: A Review of the Literature

Summary: Alterations of cognitive function are separate from disturbances of behavior seen in association with epilepsy. The nature of the cognitive disability may to a certain extent depend on the seizure type. Partial seizures, mainly derived from a temporal lobe focus, impair memory tasks, while generalized seizures seem to have more effect on attentional abilities. A number of studies, reviewed in this paper, suggest that anticonvulsant drugs further impair cognitive function. Maximal impairments are seen in patients receiving polytherapy: rationalization of polytherapy improves cognitive abilities. Studies in children and adults have allowed differentiation of the effects of various commonly used antiepileptic agents. Maximal cognitive deficits are seen with. phenytoin, while phenobarbital and sodium valproate induce moderate disturbances, and carbamazepine seems relatively free from such toxicity. Further research is needed on the interrelationship between types of seizure disorders, types of anticonvulsant medications, and cognitive function.     

Dextromethorphan: Cellular Effects Reducing Neuronal Hyperactivity

Summary: Dextromethorphan is a dextrorotary morphinan without affinity for opioid receptors, commonly used as an antitussive medication. During the past 5 years, interest in the compound and its demethylated derivative, dextrorphan, has been revived because additional neuroprotective and an-tiepileptic properties were found in in vitro studies, animal experiments, and a few clinical cases. Both morphinans are able to inhibit N -methyl-D-aspartate (NMDA) receptor channels and voltage-operated calcium and sodium channels with different potencies. The inhibition of the NMDA receptor is believed to be the predominant mechanism of action responsible for the anticonvulsant and neuroprotective properties of the compounds.