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1.
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.  相似文献   

2.
[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.  相似文献   

3.
目的 对儿童颢叶癫痫进行前瞻性MRI研究分析。探讨儿童颢叶癫痫的MRI表现特征。方法 对127例临床和脑电图检查诊断为颢叶癫痫的儿童进行MRI多序列成像.分析研究颞叶的形态结构、信号并判断海马有无萎缩性改变。结果 127例颢叶癫痫患儿中,9例(7.1%)海马有萎缩性改变,且在T2加权成像和液体率减恢复(F1AIR)成像上呈高信号。9例中,6例伴有海马受累同侧颞叶信号异常;3例伴有同侧颞叶皮层结构不良;1例伴有同侧颞叶萎缩。结论 颞叶中内侧硬化是儿童颢叶癫痫的一个相对少见原因,受累侧海马MRI表现为萎缩和信号异常,同时常伴海马外颞叶结构受累。  相似文献   

4.
目的:评估单侧海马硬化的颞叶癫痫患者头皮脑电图发作间期棘波(interictal spike,IEDs)频率与手术疗效的关系。方法:回顾性分析33例单侧海马硬化的颞叶癫痫患者头皮脑电图,随机抽取手术前1h清醒期脑电图分析其IEDs频率和分布,并据此将患者分为2类:(1)IEDs高频组和IEDs低频组;(2)IEDs单侧颞叶组和IEDs双侧颞叶组。患者经1年以上随访统计预后。用Fisher确切检验法、广义线性模型分析IEDs频率与手术疗效的关系。结果:IEDs低频组17例,其中16例(94.1%)术后发作消失;IEDs高频组16例,其中10例(62.5%)术后发作消失,两组间疗效差异存在显著性(P=0.039)。患者先兆和全面性发作的存在、病程与患者IEDs频率正相关。结论:单侧海马硬化颞叶癫痫患者清醒期IEDs频率高预示手术疗效不良。  相似文献   

5.
6.
Quantitative evaluation of MRI in patients with epilepsy can give more information than qualitative assessment. Previously developed volume-of-interest-based methods identified subtle widespread structural changes in the neocortex beyond the visualized lesions in patients with malformations of cortical development (MCD) and hippocampal sclerosis (HS) and also in MRI-negative patients with juvenile myoclonic epilepsy (JME). This study evaluates a voxel-based automated analysis of structural MRI in epilepsy. After fully automated segmentation of cerebral gray matter from structural T1-weighted, high-resolution MRI scans, we applied the automated and objective technique of statistical parametric mapping (SPM) to the analysis of gray matter of 35 control subjects, 10 patients with partial seizures and MCD, 10 patients with left temporal lobe epilepsy (TLE) and HS, 10 patients with left TLE and normal MR quantitation of the hippocampus, and 20 patients with JME. At a corrected threshold of P < 0.05, significant abnormalities were found in 3/35 controls; in all 10 patients with MCD, 6 of whom had additional lesions beyond the margins of the visualized abnormalities; in 2/10 TLE patients with HS; in 2/10 MRI-negative TLE; and in 4/20 JME patients. Group comparisons between control subjects and HS patients identified the affected left temporal lobe with an increase in gray matter in the posterior temporal lobe, but did not identify hippocampal atrophy. The group of MRI-negative TLE patients showed no abnormalities compared with control subjects. Group comparison between control subjects and JME patients identified a mesial frontal increase in gray matter. The SPM-based voxel-by-voxel comparison of gray matter distribution identified MCD and abnormalities beyond the visualized lesion in individual MCD patients. The method did not reliably identify HS in individual patients or identify abnormalities in individual MRI-negative patients with TLE or JME in a proportion larger than the chance findings in the control group. Using group comparisons, structural abnormalities in the neocortical gray matter of patients with TLE and HS were lateralized to the affected temporal lobe. In patients with JME as a group, an increase in gray matter was localized to the mesial frontal area, corroborating earlier quantitative MRI findings.  相似文献   

7.
It has traditionally been held that the hippocampus is not part of the neural substrate of working memory (WM), and that WM is preserved in Temporal Lobe Epilepsy (TLE). Recent imaging and neuropsychological data suggest this view may need revision. The aim of this study was to investigate the neural correlates of WM in TLE using functional MRI (fMRI). We used a visuo-spatial 'n-back' paradigm to compare WM network activity in 38 unilateral hippocampal sclerosis (HS) patients (19 left) and 15 healthy controls. WM performance was impaired in both left and right HS groups compared to controls. The TLE groups showed reduced right superior parietal lobe activity during single- and multiple-item WM. No significant hippocampal activation was found during the active task in any group, but the hippocampi progressively deactivated as the task demand increased. This effect was bilateral for controls, whereas the TLE patients showed progressive unilateral deactivation only contralateral to the side of the hippocampal sclerosis and seizure focus. Progressive deactivation of the posterior medial temporal lobe was associated with better performance in all groups. Our results suggest that WM is impaired in unilateral HS and the underlying neural correlates of WM are disrupted. Our findings suggest that hippocampal activity is progressively suppressed as the WM load increases, with maintenance of good performance. Implications for understanding the role of the hippocampus in WM are discussed.  相似文献   

8.
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。  相似文献   

9.
Purpose Some patients with temporal lobe epilepsy (TLE) lack evidence of hippocampal sclerosis (HS) on MRI (HS-ve). We hypothesized that this group would have a different pattern of 2-deoxy-2-[F-18]fluoro-d-glucose (FDG)-positron emission tomography (PET) hypometabolism than typical mesial TLE/HS patients with evidence of hippocampal atrophy on magnetic resonance imaging (MRI) (HS+ve), with a lateral temporal neocortical rather than mesial focus. Procedures Thirty consecutive HS-ve patients and 30 age- and sex-matched HS+ve patients with well-lateralized EEG were identified. FDG-PET was performed on 28 HS-ve patients and 24 HS+ve patients. Both groups were compared using statistical parametric mapping (SPM), directly and with FDG-PET from 20 healthy controls. Results Both groups showed lateralized temporal hypometabolism compared to controls. In HS+ve, this was antero–infero–mesial (T = 17.13); in HS-ve the main clustering was inferolateral (T = 17.63). When directly compared, HS+ve had greater hypometabolism inmesial temporal/hippocampal regions (T = 4.86); HS-ve had greater inferolateral temporal hypometabolism (T = 4.18). Conclusions These data support the hypothesis that focal hypometabolism involves primarily lateal neocortical rather than mesial temporal structures in ‘MRI-negative PET-positive TLE.’  相似文献   

10.
磁源性影像在海马硬化致癫灶定位中的应用   总被引:2,自引:0,他引:2  
目的:探讨磁源性影像对由海马硬化引起的颞叶癫痫术前致癫灶定位价值。方法:对16例海马硬化的病例术前实行脑磁图检查,并应用磁源性影像技术对致癫灶进行定位。结果:术后随访,按照南京军区总医院的评估标准:满意14例(87.5%);显著改善1例(6.25%);疗效差1例(6.25%);总有效率93%。磁源性影像定位与视频脑电图的定位完全符合率为62.5%。结论:磁源性影像可以明确海马硬化患者癫痫源异常放电位置,可以用于术前致癫灶的定位。  相似文献   

11.
颞叶癫痫的质子磁共振波谱与PET/CT及术后病理对照研究   总被引:1,自引:0,他引:1  
目的:对颞叶癫痫患者术前的质子磁共振波谱(1H MRS)与正电子发射断层扫描(PET/CT)、脑电图(EEG)及术后病理进行对照研究,评价1H MRS对颞叶癫痫的诊断价值。方法:16例颞叶癫痫病人,术前均做发作期间脑电图和/或长程脑电图监测及PET/CT检查。对28例健康志愿者和16例患者分别进行双侧海马的1H MRS采集,定量分析N-乙酰天门冬氨酸(NAA)、肌酸(Cr)和胆碱(Cho)代谢物的变化。3例患者手术切除致痫灶送病检。结果:病侧组、对侧组和对照组的NAA/Cr、Cho/Cr和NAA/(Cho+Cr)值之间的差异均有统计学意义(P<0.05)。16例患者中5例为单侧异常,11例为双侧异常,14例可确定异常侧,定位敏感度87%。结论:患者1H MRS示病侧与EEG、PET和病理改变有较好的对应性,1H MRS不仅可以发现双侧病变,而且可以指出病变严重的一侧,为术前致痫灶的定位提供可靠的依据。  相似文献   

12.
Interictal diffusion imaging studies in patients with medial temporal lobe epilepsy (MTLE) accompanied by hippocampal sclerosis (HS) have shown an increased diffusivity in the epileptogenic hippocampus. In this study, we wanted to explore the whole brain in order to determine if MTLE could have an impact on the organization and the architecture of a large cerebral network and to identify clinical factors that could mediate diffusion abnormalities. Diffusion tensor imaging (DTI) and statistical parametric mapping of the entire brain were performed in 35 well-defined MTLE patients and in 36 healthy volunteers. SPM analyses identified three abnormal areas: an increased diffusivity was detected in the epileptic hippocampus and the ipsilateral temporal structures associated with a decreased anisotropy along the temporal lobe, a decreased diffusivity was found in the contralateral non-sclerotic hippocampus, the amygdala, and the temporal pole, and finally, a decreased anisotropy was noted ipsilaterally in posterior extratemporal regions. Duration of epilepsy, age at onset, and the frequency of generalized tonic-clonic seizures or partial complex seizures did not correlate with the presence of diffusion abnormalities. Region of interest analysis in the hippocampus/parahippocampus demonstrated a correlation between lower ipsilateral diffusivity values and occurrence of epigastric aura and between higher anisotropy values in both hemispheres and history of febrile seizures. In conclusion, this study showed that diffusion abnormalities are not restricted to the pathologic hippocampus and involve a larger network. This pattern may indirectly reflect the epileptogenic network and may be interpreted as a cause or a consequence of epilepsy.  相似文献   

13.
Bonilha L  Rorden C  Castellano G  Cendes F  Li LM 《NeuroImage》2005,25(3):1016-1021
Previous research has suggested that patients with refractory medial temporal lobe epilepsy (MTLE) show gray matter atrophy both within the temporal lobes as well as in the thalamus. However, these studies have not distinguished between different nuclei within the thalamus. We examined whether thalamic atrophy correlates with the nuclei's connections to other regions in the limbic system. T1-weighted MRI scans were obtained from 49 neurologically healthy control subjects and 43 patients diagnosed with chronic refractory MTLE that was unilateral in origin (as measured by ictal EEG and hippocampal atrophy observed on MRI). Measurements of gray matter concentration (GMC) were made using automated segmentation algorithms. GMC was analyzed both voxel-by-voxel (preserving spatial precision) as well as using predefined regions of interest. Voxel-based morphometry revealed intense GMC reduction in the anterior portion relative to posterior thalami. Furthermore, thalamic atrophy was greater ipsilateral to the MTLE origin than on the contralateral side. Here we demonstrate that the thalamic atrophy is most intense in the thalamic nuclei that have strong connections with the limbic hippocampus. This finding suggests that thalamic atrophy reflects this region's anatomical and functional association with the limbic system rather than a general vulnerability to damage.  相似文献   

14.
We report on the methods and initial findings of a novel noninvasive technique, resting functional magnetic resonance imaging (fMRI) with temporal clustering analysis (TCA), for localizing interictal epileptic activity. Nine subjects were studied including six temporal lobe epilepsy (TLE) patients with confirmed localization indicated by successful seizure control after resection. The remaining three subjects had standard presurgical evaluations with inconsistent results or suspected extratemporal lobe foci. Peaks of activity, presumably epileptic, were detected in all nine subjects, using the resting functional MRI with temporal clustering analysis. In all six patients who underwent resective surgery, the fMRI with temporal clustering analysis accurately determined the epileptogenic hippocampal hemisphere (P = 0.005). In the three subjects without confirmed localization, the technique determined regions of activity consistent with those determined by the presurgical assessments. Though more studies are required to validate this technique, the results demonstrate the potential of the resting fMRI with temporal clustering technique to detect and localize epileptic activity without the need for simultaneous electroencephalography (EEG). The greatest potential benefit of this technique will be in the evaluation of patients with suspected extratemporal lobe epilepsy and patients whose standard assessments are discordant.  相似文献   

15.
Objectives: To evaluate clinical, electrophysiological, and neuroradiological factors which correlate with the prognosis in patients with mesial temporal lobe epilepsy (MTLE).

Methods: This was a single-center prospective outcome study in patients with MTLE. The patients’ family history, clinical characteristics, neurophysiological data (electroencephalography – EEG), neuroimaging, antiepileptic therapy, and outcome were collected and analyzed. The population was divided into four groups depending on the frequency of the seizures when they attended their last follow up. All variables and outcome measures were compared between the four groups.

Results: In total 83 consecutive patients were included within the four groups. Group 1 (seizure-free) consisted of 7 patients, (9%), Group 2 (rare seizures) consisted of 15 patients (18%), Group 3 (often seizures) consisted of 30 patients (36%), and Group 4 (very often seizures) consisted of 31 patients (37%). The groups did not differ significantly in demographic characteristics. There was a strong positive correlation between resistance to therapy and sleep activation on EEG (p = 0.005), occurrence of focal to bilateral seizures (p = 0.007), automatisms (p = 0.004), and the number of previously used antiepileptic drugs (AEDs) (p = 0.002). There was no association between febrile convulsions (FC), hippocampal sclerosis (HS), and the outcome that was found.

Conclusion: MTLE is a heterogeneous syndrome. Establishing the factors responsible for, and associated with, drug resistance is important for optimal management and treatment, as early identification of drug resistance should then ensure a timely referral for surgical treatment is made. This prospective study shows that sleep activation on EEG, ictal automatisms, occurrence of focal to bilateral tonic-clonic seizures, and increased number of tried AEDs are negative prognostic factors.  相似文献   

16.
海马硬化患者海马ADC值与海马体积及磁共振波谱的相关性   总被引:2,自引:2,他引:0  
目的 探讨海马硬化(HS)患者的海马表观扩散系数(ADC)值与海马体积及磁共振波谱的相关性,并评价ADC值在HS诊断中的价值。方法 对13例单侧颞叶癫痫HS患者(HS组)和20名健康志愿者(正常对照组)行常规MR及磁共振扩散加权成像(DWI)检查,并对HS患者进行海马体积测量和磁共振波谱(MRS)检查,计算双侧海马的ADC值、标准化体积、N-乙酰天门冬氨酸/(胆碱+肌酸) 及不对称指数(AI,包括AIADC、AIVOLUME及AIMRS),评价海马ADC值与体积、磁共振波谱、患者发病年龄和病程间的相关性。结果 HS组患侧海马ADC值显著高于健侧海马及正常对照组(P均<0.001),且HS组海马AIADC显著高于正常对照组(P<0.001)。HS组患侧海马ADC值与海马体积之间存在相关性(r=-0.854,P<0.001),患者海马AIADC与AIVOLUME之间也存在显著相关性(r=0.611,P<0.05)。HS组海马AIADC与病程长短存在显著正相关(r=0.676,P<0.05)。结论 测量海马ADC值有助于HS的术前诊断。HS患者海马的ADC值与海马体积及病程显著相关。  相似文献   

17.
The objective of this study was to assess temporal lobe white matter (WM) quantitatively using T2 relaxometry in patients with pharmacologically intractable temporal lobe epilepsy (TLE). T2 relaxometry was performed using a dual-echo sequence with 23 contiguous oblique coronal slices in 56 consecutive TLE patients and in 30 healthy subjects. Averages of six slices were chosen to calculate T2 relaxation time in the temporal lobe WM (WM-T2) and the hippocampus (Hippo-T2). Twenty-seven patients had unilateral hippocampal atrophy (HA), and twenty-nine patients had normal hippocampal volumes (NV) on volumetric MRI. Mean WM-T2 was increased ipsilateral to the seizure focus in TLE patients with HA and those with NV (P < 0.001). Contralateral mean WM-T2 was increased in left and right TLE with HA (P < 0.001) and in right TLE with NV (P = 0.001). There was a positive correlation between WM-T2 and Hippo-T2. Individual analysis showed a prolongation of WM-T2 in about 70% of TLE patients with HA and NV. In half of the patients, WM-T2 increase was bilateral and symmetric. However, in 33% of patients with NV and bilateral symmetric increase in Hippo-T2, WM-T2 provided a correct lateralization of the seizure focus. Regardless of the pattern of T2 abnormalities, that is, bilateral symmetric or ipsilateral, the majority of patients with HA became seizure-free after surgery, while those with NV did not have a favorable outcome. In patients with NV, WM-T2 measurement may provide additional lateralizing information compared to Hippo-T2.  相似文献   

18.
Experimental data in animals show that 5-HT(1A) receptors are predominantly located in limbic areas and suggest that serotonin, via these receptors, mediates an antiepileptic and anticonvulsant effect. In this PET study, we used an antagonist of the 5-HT(1A) receptor, [(18)F]MPPF, to assess the extent of 5-HT(1A) receptor binding changes in a group of seven temporal lobe epilepsy (TLE) patients with hippocampal ictal onset demonstrated by intracerebral EEG recording. On the basis of MRI-measured hippocampal volumes (HV), patients were classified into "normal HV" or "hippocampal atrophy" (HA). Voxel-based analyses (SPM99) were performed to objectively assess the differences in [(18)F]MPPF binding potential (BP) between patients (taken as a group or as individuals) and a database of 48 controls subjects. In the full group of patients, a significant decreased BP was detected ipsilateral to the epileptogenic zone in the hippocampus, temporal pole, insula, and temporal neocortex. This result was confirmed in the subgroup of patients with HA. In patients with normal HV, the BP decrease was restricted to the temporal pole. TLE patients also demonstrated an increased BP in various regions contralateral to the epileptogenic zone. These data suggest that in TLE patients with hippocampal seizure onset, the decrease in 5-HT(1A) receptor binding partly reflects hippocampal neuronal loss, but is also observed in various regions involved in temporo-limbic epileptogenic networks that appeared normal on MRI. Further studies are warranted to evaluate the clinical usefulness of [(18)F]MPPF-PET as compared to other established PET tracers in drug resistant TLE.  相似文献   

19.
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.  相似文献   

20.
Migraine-like features sometimes characterize the headache that follows epileptic seizure (postictal headache, PIH). We compared patients with different types of epilepsy to investigate the association between migraine-like PIH and seizure type. Subjects comprised 364 patients with partial epilepsy. Epilepsy types were temporal lobe epilepsy (TLE, n = 177), frontal lobe epilepsy (FLE, n = 116), and occipital lobe epilepsy (OLE, n = 71). Patients participated in a structured interview pertaining to PIH as well as interictal headache and family history of migraine. Headaches were classified according to the International Headache Society criteria, which was modified for this study. Forty percent had PIH and 26% of these patients had migraine-like PIH. Migraine-like PIH occurred significantly more often in cases of TLE and OLE than in cases of FLE. In addition, the incidence of interictal migraine headache was significantly higher in patients with migraine-like PIH. These results suggest that migraine-like PIH is related to particular regions of epileptogenic focus and that susceptibility to migraine headache predisposes to migraine-like PIH.  相似文献   

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