颞叶癫痫儿童灰质异常脑区与神经心理学测验的关系及意义

[目的]评估儿童颞叶癫痫（ TLE）临床表现和神经心理学测验成绩与局部脑萎缩的相关性.[方法]症状性TLE患儿14例（海马萎缩所致中颞叶癫痫 9例,颞叶新皮质损伤所致TLE 5例）,健康对照儿童14名;中颞叶癫痫（ MTLE）成人及其对照各9例.所有入组对象进行脑MRI获取T1结构像,用像素为基础的形态测定法分析图像.所有儿童进行综合神经心理学测验.[结果]TLE患儿同侧海马和海马外周区灰质体积显著减小,灰质体积减小与神经心理学测验成绩显著相关（P〈0.05）.单侧海马萎缩的MTLE患儿中,癫痫发作区域同侧的海马灰质体积显著减小,同侧扣带和对侧额中回皮质萎缩,皮质萎缩程度及范围较同类成人患者小.[结论]与成人MTLE患者相似,儿童MTLE与海马和海马外周的细胞减少有关;儿童TLE灰质萎缩的程度和范围较成人患者小,仅限于额叶区;中颞叶和额叶区灰质体积的减小与神经心理学测验成绩显著相关;TLE患儿的认知或行为障碍是神经网络损伤的结果.     

Short-term changes in bilateral hippocampal coherence precede epileptiform events

The mesial temporal lobe epilepsy syndrome (MTLE) is the most common form of focal epilepsies. MTLE patients usually respond very little to pharmacological therapy and surgical resection of temporal brain areas is mandatory. Finding less invasive therapies than resection of the sclerotic hippocampus requires knowledge of the network structures and dynamics involved in seizure generation. Investigation of the time interval immediately preceding seizure onset would help in understanding the initiation mechanisms of the seizure proper and, thereby, possibly improve therapeutical options. Here, we employed the in vivo intrahippocampal kainate model in mice, which is characterized by unilateral histological changes, resembling hippocampal sclerosis observed in human MTLE, and recurrent focal seizures. In these epileptic mice, population spikes occurred during epileptiform events (EEs) in the ipsilateral, histologically changed hippocampus, but also concomitantly in the contralateral, intact hippocampus. We studied synchronization processes between the ipsilateral, sclerotic hippocampus and the contralateral hippocampus immediately preceding the onset of EEs. We show that coherence between the two hippocampi decreased consistently and reliably for all EEs at 8 to 12 s before their onset at high frequencies (>100 Hz), without changes in power in these bands. This early decoupling of the two hippocampi indicates the time range for cellular and network mechanisms leading to increased excitability and/or synchronicity in the tissue and thus ultimately to epileptic seizures.     

动脉自旋标记技术在内侧颞叶癫痫中的应用进展

内侧颞叶癫痫（MTLE）为致痫灶起源于内侧颞叶并可伴有海马硬化的一类癫痫,随着新技术的开发与应用,影像学检查在改善其临床诊断与治疗中发挥着越来越大的作用。动脉自旋标记（ASL）是一种无创的MR成像技术。本文对ASL在MTLE相关基础研究与临床应用中的进展进行综述。     

Gray matter atrophy associated with duration of temporal lobe epilepsy

Hippocampal sclerosis is the most common abnormality associated with medial temporal lobe epilepsy (MTLE). Converging evidence supports that hippocampal sclerosis progresses with time. However, it is unclear whether extrahippocampal atrophy in patients with MTLE, similarly to hippocampal sclerosis, is an unremitting progressive process. In this article, we investigate the relationship between duration of epilepsy and gray matter concentration reduction in patients with MTLE within and outside the hippocampus. We employed a voxel-based morphometry study of MRI of the entire brain of 36 patients with drug refractory MTLE and 49 neurologically healthy age-matched controls. We performed a voxel-based parametric and nonparametric investigation of the association between gray matter concentration, age and duration of epilepsy. We complemented the investigation by extracting the gray matter concentration of regions of interest (ROIs) within the limbic system, and we investigated the association between the gray matter concentration on the ROIs and duration of epilepsy. Patients with MTLE exhibited gray matter concentration reduction that is negatively correlated with the duration of epilepsy within the ipsilateral hippocampus, temporal lobes as well as extratemporal limbic structures that are closely connected with the hippocampus. In conclusion, longer duration of refractory epilepsy was associated with a more intense hippocampal and extrahippocampal atrophy in patients with MTLE. The mechanism of progressive neuronal damage in MTLE may be related to active seizure activity within a limbic network, and early seizure control may prevent further brain atrophy in patients with refractory MTLE.     

Voxel-based diffusion tensor imaging in patients with mesial temporal lobe epilepsy and hippocampal sclerosis

BACKGROUND: Mesial temporal lobe epilepsy (mTLE) with hippocampus sclerosis (HS) is an important cause for focal epilepsy. In this study, we explored the integrity of connecting networks using diffusion tensor imaging (DTI) and two whole-brain voxel-based methods: statistical parametric mapping (SPM) and tract-based spatial statistics (TBSS). METHODS: Thirty-three consecutive patients with mTLE and HS undergoing presurgical evaluation were scanned at 3 T, a DTI data set was acquired and parametric maps of fractional anisotropy (FA) and mean diffusivity (MD) were calculated. Twenty-one patients had left hippocampal sclerosis (LHS) and 12 patients had right HS (RHS). These groups were compared to 37 normal control subjects using both SPM5 and TBSS. RESULTS: The ipsilateral temporal lobe showed widespread FA reduction in both groups. The limbic system was clearly abnormal in the LHS group, also involving the arcuate fasciculus. In RHS, changes were more restricted but also showed involvement of the contralateral temporal and inferior frontal lobe. Increased MD was found in the ipsilateral hippocampus by SPM that was only marginally detected by TBSS. In white matter regions, however, TBSS was more sensitive to changes than SPM. CONCLUSION: DTI detects extensive changes in mTLE with HS. The affected networks were principally in the ipsilateral temporal lobe and the limbic system but also the arcuate fasciculus. SPM and TBSS gave complementary information with higher sensitivity to FA changes using TBSS.     

颞叶内侧癫痫全脑灰质基于体素的MRI形态分析

目的应用MRI基于体素的形态学测量方法（VBM）,分析颞叶内侧癫痫患者全脑灰质结构的改变。方法对23例颞叶内侧癫痫患者（其中右侧病变11例,左侧病变12例）,13例年龄性别与之匹配的健康志愿者行全脑扫描,应用磁化准备快速梯度回波成像序列获取三维结构图像。数据分析采用以SPM99软件包为基础的全自动VBM技术进行处理。结果与健康对照组比较,颞叶内侧癫痫患者显示了患侧和对侧海马,以及丘脑、扣带回等边缘系统结构灰质密度的减少。额叶及小脑皮层等结构也显示弥漫灰质密度的减少。结论VBM法操作简单,不但可检测颞叶内侧癫痫海马结构的异常,还可显示海马结构以外弥漫脑灰质结构的异常。     

Voxel-based morphometry of unilateral temporal lobe epilepsy reveals abnormalities in cerebral white matter

Voxel-based morphometric (VBM) investigations of temporal lobe epilepsy have focused on the presence and distribution of gray matter abnormalities. VBM studies to date have identified the expected abnormalities in hippocampus and extrahippocampal temporal lobe, as well as more diffuse abnormalities in the thalamus, cerebellum, and extratemporal neocortical areas. To date, there has not been a comprehensive VBM investigation of cerebral white matter in nonlesional temporal lobe epilepsy. This study examined 25 lateralized temporal lobe epilepsy patients (13 left, 12 right) and 62 healthy controls in regard to both temporal and extratemporal lobe gray and white matter. Consistent with prior reports, gray matter abnormalities were evident in ipsilateral hippocampus and ipsilateral thalamus. Temporal and extratemporal white matter was affected ipsilateral to the side of seizure onset, in both left and right temporal lobe epilepsy groups. These findings indicate that chronic temporal lobe epilepsy is associated not only with abnormalities in gray matter, but also with concomitant abnormalities in cerebral white matter regions that may affect connectivity both within and between the cerebral hemispheres.     

MRI脑灰质形态学分析在双重病理所致颞叶癫痫的应用

目的应用基于体素形态学(VBM)及基于表面形态学(SBM)分析,探讨双重病理所致颞叶癫痫磁共振成像(MRI)脑灰质结构变化。方法收集病理确诊为海马硬化(HS)合并局灶性皮质发育不良(FCD)的双重病理颞叶癫痫患者36例(左侧癫痫组20例、右侧癫痫组16例)及健康对照组30例行MRI T_1WI 3D BRAVO序列扫描,使用SPM及Freesurfer软件分别进行灰质体积及皮层厚度、皮层表面积分析,并采用独立样本t检验获得有统计学差异脑区。结果左、右侧癫痫组与对照组比较,病侧大部分颞叶(含海马)灰质体积减小,左侧癫痫组同侧丘脑及杏仁核灰质体积减小,其差异均有显著统计学意义(FDR校正,P0.001,K≥20体素)。癫痫组均出现部分颞叶及颞叶以外脑区皮层增厚,但左、右侧癫痫组异常脑区存在不同;同时癫痫组病变侧颞叶脑区皮层表面积减小,上述差异均具有统计学意义(未校正,P0.01,顶点数≥100)。结论HS合并FCD致颞叶癫痫病变侧颞叶(含海马)灰质体积广泛缩小为主要形态学特征,皮层表面积减小对病变定侧也有一定作用,单纯通过皮层增厚观察双重病理中FCD存在一定局限性。     

颞叶癫痫患者的认知功能与MRI和DTI的关系研究

目的:研究颞叶癫痫患者认知功能及其与核磁共振(MRI)和弥散张量成像(DTI)的关系。方法:选取我院36例颞叶癫痫患者为癫痫组,36例同期体检健康者为对照组,分别采用简易精神状态量表(MMSE)、韦氏成人智力量表(WAIS)进行认知功能评估及MRI、DTI检查,对比2组大脑感兴趣区的平均扩散率与部分各向异性值,分析其认知功能与影像学表现的关系。结果:癫痫组的MMSE、WAIS评分均较对照组低(P均0.05);癫痫组的左右丘脑与左右内囊后肢部分各向异性值均低于对照组(P均0.05);左内囊后肢、左内囊膝部及左丘脑平均扩散率与WAIS评分呈负相关(P均0.05),左内囊前肢、左枕叶部分各向异性与MMSE评分呈正相关(P均0.05),左枕叶部分各向异性与操作智商呈正相关(P0.05),右枕叶部分各向异性与全量表智商、语言智商及操作智商呈正相关(P均0.05)。结论:颞叶癫痫患者存在一定程度的认知功能障碍,MRI和DTI可有效检出患者脑组织受损处与评估受损程度。     

血管性认知功能损害患者基于体素的全脑分数各向异性比较

目的 利用扩散张量成像研究血管性认知功能损害(VCI)患者基于体素的全脑范围内白质异常.方法 对19名血管性认知功能障碍患者和19名正常老年人进行扩散张量成像扫描,经过后处理生成分数各向异性(FA)图,在SPM2下进行头颅标准化后,对VCI组和对照组的全脑FA图进行基于体素的统计学t检验.结果 对照组和VCI组的额叶白质、外囊、扣带、颞叶白质、顶叶白质、岛叶的FA值差异具有显著性意义,而且大多以左侧为主.结论 基于体素的全脑白质FA比较能够发现VCI患者中大脑特定部位白质的异常,从而更加客观、全面地评价VCI患者的脑部改变.     

轻度Alzheimer病人与正常老年人全脑白质各向异性的比较

目的利用扩散张量成像研究轻度Alzheimer患者全脑范围内的白质异常.方法对16例正常志愿者和13例轻度Alzheimer患者进行了扩散张量成像扫描,经过后处理生成的FA图在SPM99下进行头颅标准化后,对AD组和对照组的全脑白质FA图进行基于体素的统计学比较.结果对照组和AD组的双侧内颞叶、右颞中回、左侧顶叶白质,左侧外囊,右上纵束和穹窿的各向异性FA值差异具有显著性意义.结论基于体素的全脑白质FA图比较能够发现AD患者中大脑白质的异常,从而更加全面地评价AD患者的结构改变.     

Extra-hippocampal grey matter density abnormalities in paediatric mesial temporal sclerosis

The aim of this study was to identify grey matter density abnormalities in children with temporal lobe epilepsy and mesial temporal sclerosis. Magnetic resonance T1 weighted 3D datasets were obtained in children with temporal lobe epilepsy (20 left and 10 right sided, mean age 11.9 years, range 6.6-17.5) and compared to scans obtained from age-matched controls (n = 22, mean age 12.8 years, range 7.1-17.5) using voxel-based morphometry. This method detected reduced grey matter ipsilateral to the seizure focus not only in the hippocampus, but also in the lateral temporal lobe and in extra-temporal regions including the thalamus, posterior cingulate cortex and cerebellum. Bilateral differences were present in the frontal and parietal opercular cortices and lateral temporal regions. These grey matter density reductions broadly reflect the pattern of hippocampal connections and may be caused by the disruption of cortical development by the recurrent seizures, as well as by loss of functional input from the sclerotic hippocampus.     

难治性颞叶癫痫患者棘波灶及海马突触损伤的电镜观察

目的研究颞叶癫痫皮层棘波灶及海马突触的病理变化。方法原发性难治性颞叶癫痫行手术治疗患者9例，手术中在皮层脑电监测下取棘波灶的颞叶大脑皮质和海马组织，电镜下观察。结果颞叶皮质和海马突触数量及突触结构改变。缩论颡叶皮层和海马超微结构的改变，特别是突触重组，可能是癫痫反复自发性发作的形态学基础，该病理变化与痫样活动的产生及神经系统的兴奋抑制平衡失调有关。     

A hippocampal lesion detected by high-field 3 tesla magnetic resonance imaging in a patient with temporal lobe epilepsy

Nearly 80% of patients with temporal lobe epilepsy have some types of lesion identified by conventional 1.5 tesla (T) magnetic resonance imaging (MRI). We performed high-field 3 T MRI in a 5-year-old patient with recurrent complex partial seizures who was diagnosed as having right temporal lobe epilepsy based on the results of single photon emission computed tomography and ictal video-electroencephalogram monitoring, because 1.5 T MRI failed to detect any abnormalities in the suspected region. High-field 3 T MRI revealed a small high-intensity lesion on fast spin-echo short inversion time inversion-recovery images of the hippocampus, possibly responsible for the seizures. This is the first report detecting a hippocampal lesion by 3 T MRI, which could not be found by conventional 1.5 T MRI.     

Tractography of the parahippocampal gyrus and material specific memory impairment in unilateral temporal lobe epilepsy

INTRODUCTION: Temporal lobe epilepsy (TLE) is associated with disrupted memory function. The structural changes underlying this memory impairment have not been demonstrated previously with tractography. METHODS: We performed a tractography analysis of diffusion magnetic resonance imaging scans in 18 patients with unilateral TLE undergoing presurgical evaluation, and in 10 healthy controls. A seed region in the anterior parahippocampal gyrus was selected from which to trace the white matter connections of the medial temporal lobe. A correlation analysis was carried out between volume and mean fractional anisotropy (FA) of the connections, and pre-operative material specific memory performance. RESULTS: There was no significant difference between the left and right sided connections in controls. In the left TLE patients, the connected regions ipsilateral to the epileptogenic region were found to be significantly reduced in volume and mean FA compared with the contralateral region, and left-sided connections in control subjects. Significant correlations were found in left TLE patients between left and right FA, and verbal and non-verbal memory respectively. CONCLUSION: Tractography demonstrated the alteration of white matter pathways that may underlie impaired memory function in TLE. A detailed knowledge of the integrity of these connections may be useful in predicting memory decline in chronic temporal lobe epilepsy.     

难治性局灶性癫痫的多学科团队模式诊疗策略

目的:探讨难治性局灶性癫痫的多学科团队模式(multidisciplinary team,MDT)诊疗策略.方法:介绍1例药物难治性颞叶癫痫,头皮脑电图监测示患者双侧颞区不同步放电,常规磁共振序列扫描未见明显异常,初步评估为患者病灶位置和侧向性不明.进行MDT讨论和后续进一步术前评估,明确患者致痫灶和治疗方法.结果:患...     

脑灌注磁共振成像观察内侧颞叶癫痫部分及继发全面发作

目的观察部分及继发全面发作内侧颞叶癫痫(mTLE)患者脑区灌注的差异,分析在继发全面发作中起作用的相关脑区,探讨继发全面发作的mTLE网络的相关脑区。方法选取51例mTLE患者,其中16例部分发作(PS组),35例部分发作继发全面发作(sGS组)。利用3.0T MR脉冲式动脉自旋标记(PASL)序列采集两组患者发作间期脑血流量(CBF)数据。采用体素依赖统计分析(VBA)技术对两组患者脑灌注存在差异的脑区进行评价;并基于此选取患侧颞叶、丘脑及额叶等区域作为ROI,分别评价两组患者各ROI间的CBF的相关性。结果与PS组相比(校正后,P<0.05),sGS组患者表现为发作间期患侧丘脑、基底核及部分默认模式网络区域如双侧楔前叶、前扣带回、后扣带回、内侧前额叶等CBF降低;sGS组患者患侧颞叶与额叶(r=0.50,P<0.05)、丘脑与额叶(r=0.36,P<0.05)的CBF均有明显相关性。结论丘脑在继发全面发作的癫痫活动传播中起重要作用;癫痫活动通过特定网络传播到远处脑区。部分发作继发全面发作mTLE患者相比部分性发作患者部分脑区功能受损更严重。     

Ictal Intracranial Recording from a ‘Burned-Out Hippocampus’

Objective

To present a case involving a discrepancy in the presurgical data of a patient suffering from pharmacoresistant mesial temporal lobe epilepsy.

Clinical Presentation and Intervention

A 47-year-old, female patient with complex partial seizures since her twenties came to be evaluated in the Epilepsy Surgery Unit. The ictal electroencephalogram suggested a left temporal epileptogenic zone and the magnetic resonance image showed an abnormality in the right mesial temporal lobe. Intracranial monitoring revealed a pacemaker zone in the right hippocampus that discharged fast spreading to the left mesial temporal lobe, a phenomenon known as ‘burned-out hippocampus’.

Conclusion

The intracranial recording, even though it is an invasive procedure, was necessary for the presurgical evaluation of our patient. This case demonstrates the risks of using surface electroencephalography to determine localization of epileptogenic zones.Key Words: Mesial temporal epilepsy, Presurgical evaluation, Burned-out hippocampus, Seizure propagation, Electroencephalography, Invasive recording     

颞叶致痫脑肿瘤的MRI影像分析

目的 观察和分析颞叶致痫脑肿瘤患者的临床、肿瘤病理类型和MRI表现.材料与方法 回顾性分析39例颞叶致痫肿瘤的发病年龄、病程与癫痫类型等临床资料、MRI表现、累及部位及病理类型.结果 39例颞叶肿瘤患者的癫痫发病年龄平均9.4岁,36例(92.3％)为儿童期起病;平均癫痫病程98.8个月.以复杂部分性发作居多,共29例(74.4％),其中11例伴全身性强直-震挛发作(GTCS),2例伴失神发作;GTCS和强直性发作分别为5例(12.8％)和2例(5.1％);单纯部分性发作3例(7.7％).颞叶肿瘤病理类型:节细胞胶质瘤24例(61.5％),星形细胞瘤5例(12.8％),少枝胶质细胞瘤和发育不良性神经上皮瘤各3例(7.7％),其他类型肿瘤4例(10.3％).肿瘤位于颢叶内侧和外侧分别为28例和11例;颞叶内侧肿瘤累及海马者(71.4％)显著高于颞叶外侧肿瘤(9.1％).MRI确定病灶为囊实性、实性为主和囊性为主者分别占46.2％、30.8％和23.1％; MRI增强扫描64.1％的病灶无强化.除胚胎发育不良性神经上皮瘤(DNET)位于皮层内,具有多小囊性特征外,其他各类肿瘤MRI表现缺少特异性.结论 颞叶肿瘤性癫痫好发于儿童期,多为累及颞叶内侧或外侧皮层,且为生长缓慢的小肿瘤,其中尤以节细胞胶质瘤居多.癫痫发作类型以复杂部分性发作伴有或不伴有全身强直震挛发作最为常见.     

Epilepsy associated tumors: Review article

Long-term epilepsy associated tumors (LEAT) represent a well known cause of focal epilepsies. Glioneuronal tumors are the most frequent histological type consisting of a mixture of glial and neuronal elements and most commonly arising in the temporal lobe. Cortical dysplasia or other neuronal migration abnormalities often coexist. Epilepsy associated with LEAT is generally poorly controlled by antiepileptic drugs while, on the other hand, it is high responsive to surgical treatment. However the best management strategy of tumor-related focal epilepsies remains controversial representing a contemporary issues in epilepsy surgery. Temporo-mesial LEAT have a widespread epileptic network with complex epileptogenic mechanisms. By using an epilepsy surgery oriented strategy LEAT may have an excellent seizure outcome therefore surgical treatment should be offered early, irrespective of pharmacoresistance, avoiding both the consequences of uncontrolled seizures as well as the side effects of prolonged pharmacological therapy and the rare risk of malignant transformation.