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11.
对60例临床疑为头痛型痛痫的患者进行24h脑电监测。结果表明:24h脑电监测对痛痫特殊类型的检出率明显高于常规EEG。在14例(23.3%)有痫样放电的患者中,出现痫样放电以睡眠期多于清醒期;且睡眠周期中以NREMⅠ,Ⅱ期最常见。对6例(16.2%)反复阵发出现高波幅额中线θ节律而无痫性放电的患者亦应考虑头痛型癫痫的诊断。  相似文献   
12.
提要报告1980年10月至1992年6月间,在皮质脑电描记下手术治疗颞叶癫痫55例,前颞叶切除50例,杏仁核、海马切除5例。皮质脑电描记结果说明,颞叶癫痫的痫灶绝大多数来源于颞叶外侧皮质和颞叶内侧结构。术中皮质脑电描记可提供痫灶的精确部位和范围。  相似文献   
13.
Severe myoclonic epilepsy (SMEI) or Dravet syndrome is caused by mutations of the SCN1A gene that encodes voltage-gated sodium channel alpha-1 subunit. Recently, we generated and characterized a knock-in (KI) mice with an SCN1A nonsense mutation that appeared in three independent SMEI patients. The SCN1A-KI mice well reproduced the SMEI disease phenotypes. Both homozygous and heterozygous knock-in mice developed epileptic seizures within the first postnatal month. In heterozygous knock-in mice, trains of evoked action potentials in inhibitory neurons exhibited pronounced spike amplitude decrement late in the burst but not in pyramidal neurons. We further showed that in wild-type mice the Nav1.1 protein is expressed dominantly in axons and moderately in somata of parbalbumin (PV) – positive inhibitory interneurons. Our immunohistochemical observations of the Nav1.1 are clearly distinct to the previous studies, and our findings has corrected the view of the Nav1.1 protein distribution. The data indicate that Nav1.1 plays critical roles in the spike output from PV interneurons and further, that the specifically altered function of these inhibitory circuits may contribute to epileptic seizures in the mice. These information should contribute to the understanding of molecular pathomechanism of SMEI and to develop its effective therapies.  相似文献   
14.
Limbic kindling was examined in genetically epilepsy-prone (GEPR) and non-epileptic control rats. The early stage of kindling development was accelerated in both groups of GEPR rats compared to controls. Later stages of kindling were accelerated in GEPR-9 but not GEPR-3 rats. These results indicate that GEPR rats have an enhanced susceptibility to limbic kindling and suggest that limbic brain alterations may contribute to acceleration of the early stage kindling development in GEPR rats.  相似文献   
15.
质子磁共振波谱对颞叶癫癎的诊断价值   总被引:3,自引:1,他引:2  
目的:评价磁共振质子波谱(H MRS)对颞叶癫癎的诊断价值.方法:对20例健康人和18例颞叶癫癎病人进行1H MRS采集,并定量分析了癫痫病人的N-乙酰天门冬氨酸(NAA)、肌酸(Cr)和胆碱复合物(Cho)等代谢产物的变化.结果:癫癎病人致癫灶NAA峰以及NAA/(Cho cr)、NAA/Cr和NAA/Cho比值低于病灶对侧,亦低于健康对照组.正常对照组NAA/(Cho Cr)值平均为0.78,双侧差别小于0.07.我们以NAA/(Cho Cr)值<0.68和双侧NAA/(Cho Cr)比值的差别>0.07为判断标准,18例颞叶癫癎病人中,16例为单侧MRS异常,2例为双侧异常.结论:质子磁共振波谱能无创性探测脑组织内生化及代谢改变,是诊断颞叶癫癎的有效手段之一.  相似文献   
16.
目的观察多药耐药蛋白(multidrugresistance-associatedprotein,MRP)拮抗剂丙磺舒对大鼠大脑皮层细胞外液卡马西平和苯妥英钠含量的影响,证明MRP能够减少皮层内抗癫痫药物的浓度,探讨脑内表达MRP和难治性癫痫多药耐药的关系。方法在健康大鼠大脑皮层内安置微透析探针,腹腔注射卡马西平(20mg/kg)和苯妥英钠(50mg/kg),在给药后不同时间点收集透析液,并用高效液相检测其中的药物浓度,通过微透析探针局部给于丙磺舒,观察后者能否提高大鼠大脑皮层细胞外液卡马西平和苯妥英钠的浓度。结果丙磺舒升高了皮层细胞外液中卡马西平和苯妥英钠的药物浓度,前者在给药后45min~120min显著增高(P<0.05),后者在给药后30min~150min显著增高(P<0.05)。结论MRP具有限制卡马西平和苯妥英钠通过血脑屏障的作用,引起抗癫痫药物在大鼠大脑皮层细胞外液中分布减低,MRP表达增加可能参与了难治性癫痫多药耐药机制的形成。  相似文献   
17.
Juvenile myoclonic epilepsy (JME), a common form of idiopathic generalized epilepsy, has a distinct clinical and electroencephalographic profile. Often JME is not recognized, with serious consequences on the sufferers. We examined factors contributing to the missed diagnosis even in an epilepsy clinic. Of 70 JME patients, 66 (91.4%) were not diagnosed on referral and 22 (33%) were not initially recognized in the epilepsy clinic. The correct diagnosis was established after a mean of 8.3 +/- 5.5 years from disease onset and an interval of 17.7 +/- 10.4 months from first evaluation in the epilepsy clinic. Myoclonic jerks, the hallmark of the disease, were not usually reported by patients. Similarly, relevant questioning may not be included in the history. Absence seizures antedating jerks by many years, myoclonic jerks reported as unilateral, generalized tonic-clonic seizures occurring during sleep and focal EEG abnormalities are other factors contributing to not recognizing JME. Our study reemphasizes the need to have not only a correct seizure diagnosis but also a correct epilepsy-disease diagnosis.  相似文献   
18.
Generalized Convulsive Status Epilepticus in the Adult   总被引:10,自引:7,他引:3  
David M. Treiman 《Epilepsia》1993,34(S1):S2-S11
Summary: Status epilepticus (SE) is denned as recurrent epileptic seizures without full recovery of consciousness before the next seizure begins, or more-or-less continuous clinical and/or electrical seizure activity lasting for more than 30 min whether or not consciousness is impaired. Three presentations of SE are now recognized: recurrent generalized tonic and/or clonic seizures without full recovery of consciousness between attacks, nonconvulsive status where the patient appears to be in a prolonged "epileptic twilight state," and continuous/repetitive focal seizure activity without alteration of consciousness. Generalized convulsive status epilepticus (GCSE) encompasses a broad spectrum of clinical presentations from repeated overt generalized tonic-clonic seizures to subtle convulsive movements in a profoundly comatose patient. Thus, GCSE is a dynamic state that is characterized by paroxysmal or continuous tonic and/or clonic motor activity, which may be symmetrical or asymmetrical and overt or subtle but which is associated with a marked impairment of consciousness and with bilateral (although frequently asymmetrical) ictal discharges on the EEG. Just as there is a progression from overt to increasingly subtle clinical manifestations of GCSE, there is also a predictable sequence of progressive EEG changes during untreated GCSE. A sequence of five patterns of ictal discharges has been observed: discrete electrographic seizures, waxing and waning, continuous, continuous with flat periods, and periodic epileptiform discharges on a relatively flat background. A patient actively having seizures or comatose who exhibits any of these patterns on EEG should be considered to be in GCSE and should be treated aggressively to stop all clinical and electrical seizure activity to prevent further neurological morbidity and mortality.  相似文献   
19.
20.
Temporal lobe epilepsy with varying severity: MRI study of 222 patients   总被引:2,自引:0,他引:2  
MRI was performed in 222 consecutive adult patients with temporal lobe epilepsy of varying severity from January 1991 to May 1993. The diagnosis of hippocampal sclerosis was established visually by three independent observers. The accuracy of visual assessment of hippocampal asymmetry was compared with volumetric measurements. Neuropathological correlations were obtained in 63 patients with refractory seizures. Temporal lobe abnormalities were observed in 180 patients (81 %) as follows: hippocampal sclerosis in 122 (55 %); developmental abnormalities in 16 (7.2 %); tumours in 15 (6.8 %); scars in 11 (5 %); cavernous angiomas in 10 (4.5 %); miscellaneous lesions in 6. MRI was normal or showed unrelated changes in 42 patients (19 %). Visual assessment correctly lateralised hippocampal sclerosis in 79 of the 84 patients measured (94 %). Temporal lobectomy confirmed the MRI data (side and aetiology) in all 63 operated patients. Patients with normal MRI had an older age of seizure onset and were more often drug-responsive than patients with hippocampal sclerosis. MRI showed temporal lobe abnormalities in 81 % of epileptic patients with varying severity with good neuropathological correlation. Patients with normal MRI had a less severe form of the disease. Received: 19 August 1996 Accepted: 13 November 1996  相似文献   
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