脑磁图对非病灶性新皮质癫痫术前评估的价值

目的 研究非病灶性新皮质癫痫发作间期脑磁图(MEG)与手术切除范围一致性与预后的关系.方法 25例非病灶性新皮质癫痫,术前行发作间期MEG检测以及颅内视频脑电监测(i-VEEG),术后随访1年以上并运用Engel法评价预后.结果 术后总体无发作率(Engel IA) 36％ (9/25)、有效率(Engel Ⅰ级、Ⅱ级)68％(17/25).14例MEG与手术切除范围一致组术后8例无发作,无发作率57％(8/14),有效率71％ (10/14);11例不一致组,术后无发作率9％(1/11),有效率64％(7/11),一致组术后无发作率优于不一致组(P＜0.05).结论 非病灶性新皮质癫痫发作间期MEG与手术切除范围一致与术后无发作率有明确相关性.     

The role of magnetoencephalography in pediatric epilepsy surgery

Introduction Magnetoencephalography (MEG) is a new diagnostic imaging and brain mapping device that has been recently used in the context of pediatric epilepsy, epilepsy surgery, and neuronavigation.Principles of magnetoencephalography MEG allows for the placement of magnetic spike sources on a conventional magnetic resonance imaging scan, the so-called magnetic source imaging, so that the localization of epileptiform activity in a child can be determined. Considerable effort is placed on analyzing the configuration and number of spike waves by MEG that relate to a primary epileptiform discharge. Such MEG spike clusters are corroborated now by intraoperative invasive subdural grid monitoring that show good correlation in the majority of cases. Another important role of MEG relates to the mapping of critical regions of brain function using known paradigms for speech, motor, sensory, visual, and auditory brain cortex.Future applications When linked to standard neuronavigation devices, MEG brain mapping can be extremely helpful to the neurosurgeon approaching nonlesional epilepsy cases or lesional cases where the safest and most direct route to the surgical disease can be selected. As paradigms for brain mapping improve and as MEG software upgrades become more sensitive to analyzing all types of spike sources, MEG will play an increasingly important role in pediatric neurosurgery, especially for the child with intractable epilepsy.     

Revisiting the role of magnetoencephalography in epilepsy

PURPOSE OF REVIEW: This review considers the current role of magnetoencephalography in clinical epileptology. RECENT FINDINGS: While magnetoencephalography and electroencephalography complement each other for interictal spike detection, magnetoencephalography is more sensitive in neocortical epilepsy. In temporal lobe epilepsy, magnetoencephalography can attribute epileptic activity to subcompartments of the temporal lobe and differentiate between patients with mesial, lateral and diffuse seizure onsets. In extratemporal epilepsy, magnetoencephalography provides unique information in nonlesional cases and helps to define the relationship of epileptic activity with respect to lesions and eloquent cortex. Magnetoencephalography also contributes to the clinical decision process in patients with cortical dysplasias, Landau-Kleffner syndrome and recurrent seizures after prior epilepsy surgery. Magnetoencephalography-guided re-evaluation of magnetic resonance imaging helps to reveal previously unrecognized lesions. In a presurgical setting interictal magnetoencephalography was superior to scalp electroencephalography. Complete resection of the magnetoencephalography-defined irritative zone has prognostic implications on postoperative seizure control. Magnetoencephalography can reliably localize sensorimotor and language cortex. Disadvantages of this technique include the difficulties in obtaining ictal recordings and the considerable costs involved. SUMMARY: Magnetoencephalography has been developed to a valuable noninvasive tool in clinical epileptology. The development of approaches which take into account both magnetoencephalography and electroencephalography simultaneously should provide more useful information in the future.     

SPECT and PET in nonlesional epilepsy

Clinical Epileptology - Positron emission tomography (PET) and single-photon emission computed tomography (SPECT) are applied in epilepsy mostly during presurgical assessment. Nonlesional focal...     

磁共振成像阴性颞叶癫痫的临床特点分析

目的探讨磁共振成像(MRI)阴性颞叶癫痫(nonlesional temporal lobe epilepsy,TLE-NL)患者的临床特征、记忆水平和影像学特点。方法纳入2012年9月1日至2017年8月31日在浙江大学医学院附属第二医院确诊的44例单侧TLE-NL患者和53例同期就诊单侧颞叶癫痫伴海马硬化(temporal lobe epilepsy with hippocampal sclerosis,TLE-HS)患者,对TLE-NL和TLE-HS的临床特点进行对比。同时纳入20名健康志愿者作为正常对照组。采用韦氏记忆量表评估患者和对照组记忆功能,并通过高分辨率MRI定量分析海马体积及形态,评估TLE-NL和TLE-HS患者记忆水平和海马体积的改变。结果TLE-NL患者比TLE-HS患者发病年龄更晚[(24.3±12.6)岁与(15.8±10.3)岁;t=3.684,P<0.01],癫痫病程更短[4.00(2.00,8.75)年与14.00(7.50,22.00)年;Z=-4.675,P<0.01],热性惊厥史比例[4.5%(2/44)与62.3%(33/53);χ2=32.270,P<0.01)和药物难治性比例更低[47.7%(21/44)与84.9%(45/53);χ2=15.282,P<0.01)。TLE-NL患者在性别比例、癫痫家族史、致痫灶侧别、先兆发生率、症状学类型及发作频率上与TLE-HS患者类似。TLE-NL患者与正常对照组相比无明显记忆损害(记忆商数:105.2±17.4与103.8±16.2;P=1.000),而TLE-HS患者与正常对照组相比存在明显记忆损害(记忆商数:84.5±20.3与103.8±16.2;P<0.01)。TLE-NL患者海马体积和形态与正常对照组相比无明显改变,而TLE-HS患者存在明显致痫灶同侧海马萎缩[(2953±481)mm3与(4431±505)mm3;P<0.01),形态分析结果提示萎缩以海马头及海马体部明显。结论TLE-NL是一类有别于TLE-HS的颞叶癫痫综合征,具有发病年龄晚、病程短、热性惊厥史少、药物难治性癫痫发生率较低、无明显记忆损害及海马萎缩的临床特点。     

Hyperventilation-induced ictal fear in nonlesional temporal lobe epilepsy

Hyperventilation is a traditional seizure-provoking procedure used mainly in idiopathic generalized epilepsy and with a relatively limited role in partial epilepsy. Ictal fear is a rare seizure semiology seen in temporal lobe epilepsy. It has been suggested that the amygdala and anterior hippocampus are involved in generating ictal fear. We describe a rare patient with nonlesional temporal epilepsy who, while hyperventilating during an electroencephalography recording, developed complex partial seizures presenting as ictal fear. The particular sensitivity of the anterior hippocampus (probably the amygdala) to hypocapnia might be an important factor contributing to seizures. To avoid misdiagnosing this unusual condition as a pseudo-seizure, a detailed history and seizure semiology, as well as a concurrent electroencephalography recording, are mandatory.     

致灶切除治疗无病灶中央区癫

目的总结致灶切除术治疗无病灶中央区癫的诊治经验。方法回顾性分析11例无病灶中央区癫病人的临床资料,所有病人均放置颅内电极,采用皮质脑电图监测定位癫发作起源区,皮质电刺激定位功能区,采用术中唤醒行致灶切除术。结果随访11例,时间17~32个月,按照Engel分级:Ⅰ级3例,Ⅱ级3例,Ⅲ级2例,Ⅳ级3例。术后出现肢体功能障碍3例,其中2例分别于术后2周及3个月恢复;残留手指活动不灵1例。结论在颅内电极精确定位功能区及致灶的前提下,采用致灶切除术治疗无病灶中央区癫,可获得满意疗效。     

难治性癫(癎)手术前脑磁图定位的临床价值

目的 评价脑磁图对难治性癫(癎)手术前定位的临床价值.方法 52例难治性癫(癎)患者均于手术前进行MRI、脑磁图、头皮脑电图和视频脑电图等神经电生理学检查,并与手术中侵入性硬膜下皮质脑电图定位准确性进行比较.结果 与手术中侵人性硬膜下皮质脑电图比较,MRI定位区域与手术区域相距≤2cm×2cm者34例,73.53%(25/34)获得良好手术疗效(Engel方案Ⅰ～Ⅱ级),与手术区域相距>2cm×2cm者3例,66.67%(2/3)手术疗效良好(Engel方案Ⅰ～Ⅱ级);定位敏感度为89.47%,特异度为78.57%,准确度为86.54%.脑磁图定位区域与手术区域相距≤2cm×2cm者45例,91.11%(41/45)手术疗效良好(Engel方案Ⅰ～Ⅱ级),与手术区域相距>2cm×2cm者7例,42.86%(3/7)获得良好手术疗效(Engel方案Ⅰ～Ⅱ级);定位敏感度为97.37%,特异度为71.43%,准确度为90.38%.视频脑电图定位区域与手术区域相距≤2cm×2cm者43例,69.77%(30/43)手术疗效良好(Engel方案Ⅰ～Ⅱ级),与手术区域相距>2cm×2cm者9例,44.44%(4/9)手术疗效良好(Engel方案Ⅰ～Ⅱ级);定位敏感度为92.11%,特异度为42.86%,准确度为78.85%.结论 难治性癫(癎)患者采用手术前脑磁图定位较其他癫(癎)灶定位方法更为精确,对手术切除癫(癎)灶具有临床指导意义.     

Surgery for extratemporal nonlesional epilepsy in children: a meta-analysis

Purpose

Previous small studies have demonstrated that seizure outcomes following surgery for extratemporal lobe epilepsy (ETLE) in children are worse than those for temporal lobe epilepsy. We have conducted a meta-analysis of the available literature to better understand ETLE surgical outcomes in children.

Methods

We searched PubMed (1990–2009) for appropriate studies using the following terms: ETLE, ETLE surgery, ETLE surgery outcome, frontal lobe epilepsy, occipital lobe epilepsy, and parietal lobe epilepsy. Our collected data included patient age at seizure onset and surgery, the cerebral lobe involved with epileptogenesis, MRI findings, predominant seizure semiology, intracranial monitoring use (electrode implantation), epileptic region histopathology, and postoperative seizure outcome. Statistical analysis was performed to determine associations among these variables and postoperative outcome.

Results

Ninety-five patients from 17 studies satisfied the inclusion criteria. Pathological findings (p?=?0.039) and seizure type (p?=?0.025) were significantly associated with outcome: A larger proportion of patients with cortical dysplasia and complex partial seizures experienced better outcomes. Age at surgery (p?=?0.073) and the cerebral resection site (p?=?0.059) were marginally associated with seizure outcome.

Conclusions

This study confirms previous reports: Surgical outcomes for ETLE epilepsy are significantly worse than those for temporal lobe epilepsy. The reasons for this difference may include the diffuse nature of the pathology involved in ETLE, difficulty in localizing the seizure focus in young children, and involvement of “eloquent” nonresectable cortex in epileptogenesis. Because of the reporting variability among different epilepsy centers, more uniform protocols are necessary for fair evaluation and comparison of outcomes among the different centers.     

脑磁图与神经导航结合在癫痫外科的应用

目的探讨脑磁图定位和神经导航方法二者结合在癫痫外科的应用价值。方法选择12例顽固性癫痫手术,术前脑磁图确定皮质癫痫灶及中央后回感觉皮质范围,然后与神经外科导航系统结合应用于手术当中。结果脑磁图癫痫灶定位与术中皮质脑电图定位符合率100％。按Engel分级作为癫痫疗效标准,术后癫痫发作完全停止9例(1级),发作减少90％以上2例(2或3级),发作减少不到90％1例(4级)。无一例出现手术后神经功能障碍。结论脑磁图是无创确定癫痫灶和功能区皮质空间位置关系的重要工具,脑磁图定位结合神经导航方法的应用可使癫痫外科手术更精确,侵袭更小。     

Genetics of nonlesional focal epilepsy in adults and surgical implications

Clinical Epileptology - Nonlesional focal epilepsies (nlFE) represent a&nbsp;heterogenous group of syndromes. They encompass self-limited focal epilepsies of childhood and youth, rare focal,...     

Ictal magnetoencephalography in temporal and extratemporal lobe epilepsy

PURPOSE: We evaluated visual patterns and source localization of ictal magnetoencephalography (MEG) in patients with intractable temporal lobe epilepsy (TLE) and extratemporal epilepsy (ETE). METHODS: We performed spike and seizure recording simultaneously with EEG and MEG on two patients with TLE and five patients with ETE. Scalp EEG was recorded from 21 channels (10-20 international system), whereas MEG was recorded from two 37-channel sensors. We compared ictal EEG and MEG onset, frequency, and evolution and performed MEG dipole source localization of interictal spikes and early ictal discharges and co-registered dipoles to brain magnetic resonance imaging (MRI). We correlated dipole characteristics with intracranial EEG, surgical resection, and outcome. RESULTS: Ictal MEG lateralized seizure onset in both TLE patients and demonstrated ictal onset, frequency, and evolution in accordance with EEG. Ictal MEG source analysis revealed tangential vertical dipoles in the anterolateral angle in one patient, and anterior dipoles with anteroposterior orientation in the other. Intracranial EEG revealed regional entorhinal seizure onset in the first patient. Both patients became seizure free after temporal lobectomy. In ETE, ictal MEG demonstrated visual patterns similar to ictal EEG and had concordant localization with interictal MEG in all five patients. Two patients underwent surgery. Ictal MEG localization was concordant with intracranial EEG in both cases. One patient had successful outcome after surgery. The second patient did not improve after limited resection and multiple subpial transections. CONCLUSIONS: Ictal MEG can demonstrate ictal onset frequency and evolution and provide useful localizing information before epilepsy surgery.     

Genetic analysis of tuberous-sclerosis genes 1 and 2 in nonlesional focal epilepsy

Germline mutations of TSC1 (harmartin) and TSC2 (tuberin) are known to cause tuberous sclerosis (TSC), an autosomal dominant disorder with severe neurological and systemic manifestations. In addition, increasing data indicate aberrant patterns of allelic variants in patients with lesion-associated epilepsy, but absence of other stigmata of TSC. Animal models of TSC suggested that mutations in the TSC2 gene, even in absence of manifest neuropathological changes, induce aberrant neuronal activity. On this basis, we have carried out a mutational analysis of TSC1 and TSC2 in patients with pharmarcoresistant focal epilepsy without evidence of epileptogenic lesions on neuroradiological and histopathological examination (n=10). SSCP analysis revealed an allelic variant of TSC2 to be significantly increased (exon 41: 50.0% vs controls 14%, P=0.0132), which previously was reported to be increased in gangliogliomas and mineralized focal cortical dysplasia as well. Our data suggest allelic imbalances of TSC2 in nonlesional focal epileptic tissue.