以癫痫为首发症状的颞叶海绵状血管畸形的手术治疗方式

目的探讨以癫痫为首发症状的颞叶及颞叶内侧海绵状血管畸形的手术治疗方式。方法回顾性分析广东三九脑科医院2009~2013年手术治疗的49例以癫痫为首发症状的颞叶及颞叶内侧海绵状血管畸形患者,其中全面性强直-阵挛性发作26例,复杂部分性发作23例,20例行单纯病灶切除(A组),29例根据术中脑电监测结果,病灶及颞叶及/或内侧结构癫痫灶扩大切除术(B组)。结果采用Engel效果分级,A组中Ⅰ级为70%,Ⅱ级为20%,Ⅲ级10%;病理检查均为海绵状血管畸形。B组中Ⅰ级89.66%,Ⅱ级6.9%,Ⅲ级3.44%;病理检查为海绵状血管畸形,其中25例包括海马硬化,3例皮质发育不良。术中及术后均无明显并发症及死亡患者。结论对以癫痫为首发症状的颞叶海绵状血管畸形患者,通过积极的手术治疗可有效控制癫痫发作。结合术前及术中脑电结果,采用选择性扩大切除癫痫灶,对控制癫痫更为有效。颞叶及颞叶内侧海绵状血管畸形患者可能存在双重病理改变。     

Surgical treatment of temporal lobe epilepsy associated with subcortical ectopic gray matter under the guidance of intraoperative electrocorticography.

We describe a dual pathology presenting as intractable temporal lobe epilepsy associated with subcortical ectopic gray matter. The patient was a 28-year-old male with a 12-year history of refractory temporal lobe epilepsy. Preoperative diagnostic imaging revealed right hippocampal sclerosis, in addition to subcortical ectopic gray matter extending from the posterior end of the inferior horn of the right lateral ventricle to the cerebral parenchyma in the temporoparietal lobe. As surgical therapy for epilepsy, right anterior temporal lobectomy with amygdalohippocampectomy was initially performed. Intraoperative electrocorticography (ECoG) was extremely useful at this point in determining the range of excision of ectopic gray matter after resection of mesial temporal lobe structures. Based on ECoG findings, about 50% of the ectopic gray matter was excised. As of 2 years postoperatively, the patient has remained seizure free with no medication. In cases concomitantly manifesting hippocampal sclerosis and subcortical ectopic gray matter, epilepsy may be associated with dual pathology. This case report raises the potentially important issue of the possible presence of areas of structural abnormality that are non-epileptogenic.     

Surgical pathology of chronic epileptic seizure disorders: experience with 63 specimens from extratemporal corticectomies,lobectomies and functional hemispherectomies

The surgical treatment of chronic pharmacoresistant epilepsies is increasing rapidly. Although several studies have reported on histopathological findings in temporal lobe epilepsy, little is known about the surgical pathology of other seizure disorders. Here we report the histopathological fingings in 63 consecutive surgical specimens of patients who were operated for chronic pharmacoresistant epileptic seizures other than temporal lobe epilepsy (37 corticectomies, 19 functional hemispherectomies, 5 lobectomies, 1 multilobectomy, and 1 frontal lobe deafferentiation combined with a temporal lobectomy). There were structural lesions in 85.7% of the specimens. In 16 cases (25.4%) the predominant lesions were malformative (focal glioneuronal hamartias and hamartomas, vascular malformations, abundant ectopic neurons in the white matter, microgyria, and arachnoid cyst). Lesions indicating preor perinatal necrosis such as porencephaly, ulegyria, and congenital hemiatrophy were present in 7 cases (11.1%). Twelve specimens (19.0%) contained low-grade neoplasms (7 gangliogliomas, 3 astrocytomas, 1 oligoden-droglioma and 1 oligoastrocytoma). There were 3 cases of Rasuussen encephalitis, 1 specimen with atrophy and gliosis due to previous herpetic encephalitis and 1 case with an old abscess wall. Posttraumatic or postoperative changes were the predominant finding in 7 specimens (11.1%). In 7 patients there were only nonspecific changes such as cortical atrophy and gliosis or old hemorrhage. No structural alterations were identified in 9 specimens (14.3%). The findings suggest that the structural lesions observed in the great majority of the specimens were closely related to the pathogenesis of intractable seizures.Supported by a center grant from the University of Bonn Medical Center and the State of Nordrhein-Westfalen     

脑皮质发育不良继发顽固性癫痫的病理分型及手术治疗

目的 探讨局灶性脑发育不良(FCD)的临床特征、病理学、影像学的特点及手术疗效.方法 42例外科手术切除致痫灶并经病理证实为FCD的患者中,根据Palmini病理学分型进行分类,并对其临床特征、影像学特点及手术疗效进行回顾性分析.结果 42例患者中,按致痫灶部位分类颢叶24例、额叶14例、顶叶6例及枕叶3例,其中多脑叶5例.术前影像学检查阳性率62%.组织学分型FCDⅠA型9例,FCDⅠB型21例,FCDⅡA型5例,FCDⅡB型7例,其中以FCD Ⅰ B型最为常见,多位于颞叶且常伴有海马硬化.所有患者术后至少随访1年以上,癫痫术后治愈率FCD位于颞叶67%,颞叶以外43%(EngleⅠa).结论 FCD是难治性癫痫常见的病理学改变,其病理分型与临床特征和致痫灶部位存在相关性,为制定手术方案和判定手术效果提供了依据.     

Magnetic resonance spectroscopy and histopathological findings in temporal lobe epilepsy

PURPOSE: In some patients with temporal lobe epilepsy, histopathological evaluation of resected brain tissue after surgical treatment may reveal several features indicative of discrete cortical malformations. We sought to determine whether these histopathological features were accompanied by hippocampal changes detectable preoperatively by proton magnetic resonance (MR) spectroscopy and to evaluate their relationship with postoperative outcome. METHODS: In 25 consecutive temporal lobe epilepsy patients who were scheduled for surgical treatment, MR spectroscopy was performed, and resected brain tissue was analyzed histopathologically for the presence of discrete cortical malformations (e.g., microdysgenesis). Outcome was assessed in all patients with an average postoperative period of 26 months. RESULTS: In 13 patients, we found subtle, histopathologically detectable signs of cortical malformation: 6 of them with concomitant hippocampal sclerosis (dual pathology) and 7 without. The latter subgroup had a worse surgical outcome and showed enhanced bilateral and/or contralateral pathological changes in the hippocampal formation when investigated by MR spectroscopy. CONCLUSIONS: These data suggest that by showing contralaterally or bilaterally abnormal spectra, MR spectroscopy might be able to indicate pathological changes in subtle developmental disorders that are possibly more widespread over the brain. This observation may improve noninvasive diagnosis in presurgical evaluation and the neurobiological understanding of cortical malformations in pharmacoresistant temporal lobe epilepsy.     

Hippocampal synaptic pathology in patients with temporal lobe epilepsy

Immunostaining of synaptic terminals was studied in the hippocampus of 26 patients who had surgical resections for intractable temporal lobe epilepsy. Two monoclonal antibodies (EP10 and SP12) reactive with distinct synaptic antigens were used on paraffinembedded tissues. The results indicated qualitative reductions on synaptic terminals in CA4 and other regions where cell loss is reported. The inner molecular layer of the dentate gyrus was observed to have increased synaptic immunostaining. Synaptic terminal loss in CA4 and redistribution in the molecular layer were most frequent in cases with hippocampal sclerosis. However, both forms of synaptic pathology were also noted in most cases where the pathological findings were classified as indefinite, and in some cases associated with mass lesions of the temporal lobe. These results support the importance of neuronal loss and synaptic reorganization as possible mechanisms of illness in epilepsy. They also indicate that synaptic immunostaining may be a useful adjunct to routine neuropathological diagnostic techniques.Supported by the British Columbia Health Research Foundation and the Theodore and Vada Stanley Foundation     

Multinodular and vacuolating neuronal tumour of the cerebrum: a rare neuroimaging incidentaloma or a potentially treatable cause of focal epilepsy?

Multinodular and vacuolating neuronal tumour (MVNT) of the cerebrum is a relatively new, well defined histopathological and neuroradiological entity, in many cases associated with an early adult‐onset epilepsy. These lesions have an indolent course and resemble both malformative and neoplastic processes, combining a focal developmental anomaly and a low‐grade tumour. Herein, we report a case of a 48‐year‐old female patient with left temporal lobe epilepsy associated with MVNT. In addition, a comprehensive review of all the previously published cases is provided with a focus on seizure‐related cases, surgical treatment, and postoperative outcome.     

Psychiatric co-morbidity in 75 patients undergoing epilepsy surgery: lack of correlation with pathological findings

BACKGROUND: Psychiatric disorders may occur in patients with intractable partial epilepsy after surgical treatment. Previous reports attributed the presence of psychological adverse events to specific pathological entities such as dysembryoplastic neuroepithelial tumors (DNETs) and gangliogliomas. The rationale for the present study is to evaluate the importance of the surgical pathology in individuals undergoing epilepsy surgery. METHODS: The patients were separated into three groups based on the surgical pathology: group I ganglioglioma (N=25), group II DNETs (N=25), and group III mesial temporal sclerosis (N=25). Thirteen of the 75 patients (17.3%) had a preexisting psychiatric disorder. The most common preoperative psychiatric diagnosis was depression (N=4). Sixty-three of the lesions (84%) were restricted to the temporal lobe. The operative strategy included resection of the lesion and epileptogenic cortex. Sixty-two of the 75 patients (83%) were rendered seizure-free. RESULTS: Eight of the 75 patients (10.7%) had an acquired psychiatric illness following surgical treatment. A mood disorder developed in three patients after surgery. No statistical difference emerged in preoperative psychiatric co-morbidity (no group difference; p=1.0) or in newly diagnosed postoperative psychiatric disease (group I vs. II, p=0.67; group I vs. III, p=1.0; and group II vs. III, p=0.67) within the three surgical pathology groups. CONCLUSION: This study indicates that the presence of psychiatric disease before and after surgery for intractable partial epilepsy, predominantly of temporal lobe origin, was independent of the pathological findings.     

Alterations of hippocampal acetylcholinesterase in human temporal lobe epilepsy

Hippocampal sclerosis is the most common pathological finding associated with human temporal lobe epilepsy. Histochemical study with acetylcholinesterase (AChE) staining was used to investigate 7 surgically resected temporal lobes with hippocampal sclerosis from patients with temporal lobe epilepsy. In all 7 specimens, an abnormal but consistent pattern of staining was noted. In the hilum of the dentate gyrus, AChE-rich polymorphic cells were relatively preserved in comparison to the pyramidal neurons. In Ammon's horn, AChE fibers were lost in regions corresponding to the pyramidal cell dropout. AChE fibers were also lost along the inner portion of the molecular layer of the dentate gyrus, yet they were preserved within the outer portions of the molecular layer. These findings provide additional evidence for the relative selectivity of hippocampal pathology in human temporal lobe epilepsy.     

Marked accumulation of oligodendroglia‐like cells in temporal lobe epilepsy with amygdala enlargement and hippocampal sclerosis

Although an increasing number of cases of temporal lobe epilepsy (TLE) with ipsilateral amygdala enlargement (AE) have been reported, there are few pathological reports, and no clear consensus has been established. Oligodendroglia or oligodendroglia‐like cells (OLCs) have recently attracted attention in epilepsy studies. Here, we report the clinical and pathological findings of a 40‐year‐old male TLE patient with AE and hippocampal sclerosis, in whom histopathological study demonstrated remarkable clustering of OLCs around the uncus. The patient began to have refractory seizures at the age of 14, and preoperative MRI revealed left amygdala enlargement and left hippocampal atrophy. Other examinations were consistent with left mesial temporal epileptogenicity. He underwent surgical resection and achieved seizure freedom. Histopathological study of the amygdala showed swollen neurons with relatively large bodies and thick neurites, accompanied by vacuolar degeneration in the background. Additionally, there were marked clusters of OLCs with round nuclei and densely stained chromatin around the uncus. The OLCs were Olig2‐positive. In the hippocampus, severe cell loss in CA1 and granule cell dispersion in the dentate gyrus were found. These findings may provide some insights for further pathological investigations of TLE with non‐neoplastic AE.     

伴海马硬化的颞叶内侧癫痫的外科治疗(附22例临床分析)

目的探讨伴海马硬化的颞叶内侧癫痫的手术疗效。方法对22例术前诊断伴海马硬化的颞叶癫痫患者,在术中脑电监测下行颞前叶及颞叶内侧结构切除术。结果术后病理诊断均为海马硬化。术后无重大并发症,随访均无癫痫发作。结论伴海马硬化的颞叶内侧癫痫的手术效果良好,确诊后应尽早手术治疗。     

Experimental Models of Temporal Lobe Epilepsy: New Insights from the Study of Kindling and Synaptic Reorganization

Summary: Temporal lobe epilepsy is a common localization-related epileptic syndrome characterized by complex partial seizures, ictal and interictal epileptic discharges arising from limbic structures of the temporal lobe, and association with hippocampal sclerosis. Temporal lobe epilepsy may follow perinatal injury and febrile convulsions, may be progressive, and frequently becomes refractory to standard antiepileptic therapy. The neurobiology that underlies these features of temporal lobe epilepsy is not known. Recent studies in experimental models have provided new insights that may help clarify the relationship of seizures, hippocampal sclerosis, and temporal lobe epilepsy. Observations from the study of the hippocampus with kainic acid-induced lesions, the kindling model, and other experimental models of epilepsy have demonstrated that seizures induce structural and electrophysiologic alterations in hippocampal pathways that may lead to increased excitability and could play a role in the development and progression of temporal lobe epilepsy. These alterations include mossy fiber synaptic reorganization, induction of NMDA-mediated synaptic transmission, and progressive hippocampal neuronal loss induced by brief kindled seizures. Some of the structural alterations induced by kindling have also been observed in the human epileptic temporal lobe, raising the possibility that mechanisms operative in kindling may play a role in the pathogenesis of hippocampal sclerosis and in the syndrome of human temporal lobe epilepsy.     

Neuronal loss and gliosis of the amygdaloid nucleus in temporal lobe epilepsy

Although clinical and electrophysiological evidence indicates that the amygdaloid body plays an important role in the pathogenesis of temporal lobe epilepsy, there are very few detailed data on histopathological changes in this nucleus in epilepsy patients. In the present study we have examined the lateral nucleus of the amygdaloid body in 70 surgical specimens from patients with temporal lobe epilepsy and in 10 control specimens with respect to neuronal density and gliosis. The results were compared to the neuronal loss in the hippocampal formation. Our goal was to examine the pathological alterations of the amygdaloid body and their correlation with other morphological changes in temporal lobe epilepsy. In epilepsy patients with Ammon’s horn sclerosis or focal lesions of the temporal lobe, the neuronal density of the lateral amygdaloid nucleus was significantly decreased as compared to normal controls (P < 0.001). Overall, the mean volumetric density in epilepsy patients was reduced to 59% of that in normal individuals. There was no correlation between the neuronal density in the lateral amygdaloid nucleus and that in the different segments of the hippocampal formation or to the age at onset or the duration of epilepsy. The neuronal loss of the amygdaloid nucleus correlated well with the presence of fibrillary gliosis. Our findings demonstrate that the amygdaloid body is severely altered in most patients with temporal lobe epilepsy and that these changes are independent of those in the hippocampus. The presence of neuronal loss and gliosis in the amygdaloid nucleus of patients with focal lesions but no Ammon’s horn sclerosis is compatible with an involvement of the amygdala in secondary epileptogenesis. Received: 28 September 1996 / Revised, accepted: 7 January 1997     

Neuroimaging in Partial Epilepsy: Structural Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) is a noninvasive technique that has been shown to be the structural neuroimaging procedure of choice in evaluating patients with partial or localization-related epilepsy. The diagnostic yield of MRI has been confirmed in patients with partial epilepsy related to mesial temporal sclerosis (MTS) or foreign-tissue lesions. Magnetic resonance imaging may be used preoperatively to identify patients with intractable partial epilepsy who have surgically remediable epileptic syndromes. Preoperative MRI studies are predictive of long-term seizure outcome in patients receiving surgical treatment. Analysis of hippocampal formation size has also been shown to correlate with the neurocognitive outcome following temporal lobe surgery. A recent development involving subtraction ictal single photon emission computed tomography (SPECT) coregistered with structural MRI (SISCOM) has important clinical applications. SISCOM studies are more sensitive and specific than visual side-by-side interpretation of interictal and ictal SPECT scans. Also, SISCOM images have been shown to have prognostic importance in patients undergoing surgical treatment for epilepsy.     

Hippocampal sclerosis-Origins and imaging

The association between hippocampal sclerosis (HS) and epilepsy has been known for almost two centuries. For many years, HS was studied in postmortem series; however, since the mid-20th century, surgical specimens from temporal lobe resections have provided important new knowledge. HS is the most common pathology underlying drug-resistant mesial temporal lobe epilepsy (MTLE), a syndrome with a characteristic history and seizure semiology. In the early 1990s, it was recognized that magnetic resonance imaging (MRI) could detect HS. The standard MRI protocol for temporal lobe abnormalities uses coronal slices perpendicular to the long axis of the hippocampus. The MRI features of HS include reduced hippocampal volume, increased signal intensity on T(2) -weighted imaging, and disturbed internal architecture. The histopathologic diagnosis of HS is usually straightforward, with neuronal loss and chronic fibrillary gliosis centered on the pyramidal cell layer. There are several patterns or subtypes of HS recognized from surgical series based on qualitative or quantified assessments of regional neuronal loss. The pathologic changes of HS include granule cell dispersion, mossy fiber sprouting, and alterations to interneurons. There may also be more extensive sclerosis of adjacent structures in the medial temporal lobe, including the amygdala and parahippocampal gyrus. Subtle cortical neuropathologies may accompany HS. The revised classification of dysplasias in epilepsy denotes these as focal cortical dysplasias type IIIa. Sometimes, HS occurs with a second lesion, either in the temporal lobe or extratemporal, most often ipsilateral to the HS. HS on preoperative MRI strongly predicts good seizure outcome following temporal lobe resection (TLR). If adequate MRI shows no structural correlate in patients with MTLE, functional imaging studies are valuable, especially if they are in agreement with ictal electroencephalography (EEG) findings. Focal hypometabolism on 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) ipsilateral to the symptomatic temporal lobe predicts a good surgical outcome; the added value of (11) C-Flumazenil-PET (FMZ-PET) and proton magnetic resonance spectroscopy (MRS) is less clear. Surgical methods have evolved, particularly resecting less tissue, aiming to preserve function without compromising seizure outcome. Around two thirds of patients operated for MTLE with HS obtain seizure freedom. However, the best surgical approach to optimize seizure outcome remains controversial.     

Commentary: How Has Neuroimaging Improved Patient Care?

Summary: Neuroimaging has significantly altered the management of patients with partial epilepsy. Magnetic resonance imaging (MRI) has been demonstrated to be a reliable and accurate indicator of the common pathologic findings underlying a partial seizure disorder. Intracranial mass lesions have been shown to be highly coherent with the localization of the epileptogenic zone. An MRI-identified epileptogenic lesion affects the selection of patients for epilepsy surgery and alters the diagnostic evaluation and the operative strategy. The results of the MRI preoperatively have prognostic importance in patients undergoing surgical treatment for partial epilepsy. Patients with lesional epileptic syndromes are considered favorable candidates for surgical ablative treatment. Hippo-campal volume studies may predict the neurocognitive outcome in patients undergoing temporal lobe surgery. The use of MRI has resulted in a reduction in chronic intracranial EEG monitoring at most epilepsy centers, especially in patients with lesional pathology. MRI may be a reasonable initial "screening" procedure in selected patients with intractable partial epilepsy before consideration of a presurgical evaluation. A classification of partial epilepsy is proposed, based on the results of MRI, that may be useful for patients being considered for surgical treatment. Importantly, preoperative MRI must be correlated with the electrophysiologic studies and ictal semiology before decision-making regarding surgical therapy.     

Magnetic resonance imaging-based volume studies in temporal lobe epilepsy: pathological correlations

We performed a prospective study correlating magnetic resonance imaging volume measurements of the hippocampal formation with histopathology in 24 patients with intractable partial epilepsy who subsequently underwent an anterior temporal lobectomy for their seizure disorder. Patients with mass lesions verified pathologically were excluded from this study. In 71% of patients, quantitative hippocampal formation atrophy correctly lateralized the temporal lobe of seizure origin; in 29%, the volume study was indeterminant. The severity of the pathological alterations in the hippocampus correlated with the hippocampal formation volume determination. Mesial temporal sclerosis was identified in the surgically excised temporal lobe in 15 patients. The magnetic resonance imaging volume studies indicated hippocampal atrophy in the temporal lobe resected in 14 of the 15 patients. Magnetic resonance imaging-based volume measurements of the hippocampal formation increase the diagnostic yield of magnetic resonance imaging scanning in patients with intractable partial epilepsy related to mesial temporal sclerosis.     

Predictors of outcome and pathological considerations in the surgical treatment of intractable epilepsy associated with temporal lobe lesions

OBJECTIVES: To evaluate the influence of clinical, investigative, and pathological factors on seizure remission after temporal lobectomy for medically intractable epilepsy associated with focal lesions other than hippocampal sclerosis. METHODS: From a series of 234 consecutive "en bloc" temporal resections for medically intractable epilepsy performed between 1976 and 1995, neuropathological examination disclosed a focal lesion in 80. The preoperative clinical, neuropsychological, interictal EEG, and neuroimaging characteristics of these patients were assembled in a computerised database. The original neuropathological material was re-examined for lesion classification and completeness of removal. The presence of additional cortical dysplasia and mesial temporal sclerosis was also noted. Survival analysis was performed using Kaplan-Meier curves and actuarial statistics. Logistic regression analysis was used to establish the independent significance of the clinical variables. RESULTS: The probability of achieving a 1 year seizure remission was 71% by 5 years of follow up. Factors predicting a poor outcome on multivariate analysis included the need for special schooling and a long duration of epilepsy. Generalised tonic-clonic seizures, interictal EEG discharges confined to the resected lobe, demonstration of the lesion preoperatively on CT, and complete histological resection of the lesion were not predictive of outcome. Neuropsychological tests correctly predicted outcome in left sided cases but apparently congruent findings in right sided resections were associated with a poor outcome. Pathological reclassification established the dysembryoplastic neuroepithelial tumour as the commonest neoplasm (87%) in this series, with a significantly better seizure outcome than for developmental lesions, such as focal cortical dysplasia. CONCLUSIONS: The findings highlight the importance of dysembryoplastic neuroepithelial tumour in the pathogenesis of medically refractory lesional temporal lobe epilepsy and the prognostic significance of preoperative duration of epilepsy emphasises the need for early recognition and surgical treatment. Cognitive and behavioural dysfunction, however, is associated with a lower seizure remission rate, independent of duration of epilepsy.     

Cerebral cavernous malformations in the setting of focal epilepsies: pathological findings,clinical characteristics,and surgical treatment principles

Cavernous cerebral malformations (CCMs) are a well-defined epilepsy-associated pathology. They represent lesions/conglomerates of abnormally configured vessels leading to seizures either as a result of physiological changes affecting the cerebral cortex immediately surrounding the CCM (an epileptogenic mechanism that is relevant for both temporal and extratemporal lesions), or as a result of promoting epileptogenicity in remote but anatomo-functionally connected brain regions (a mechanism that is particularly relevant for temporal lobe lesions). This review details the pathological findings in CCMs and discusses the mechanisms of epileptogenicity in this context. The bulk of the review will focus on therapeutic strategies. Medical therapy using antiepileptic drugs is recommended as a first-line therapy, but surgical removal of the CCM with the surrounding cortex should be pursued if seizures prove to be drug resistant. Early timing of the resection and complete removal of any associated epileptic pathology are critical for best outcomes. In addition to reviewing the available data from prior series, we present original research from two specialized epilepsy centers targeted at answering particularly pressing clinical questions mainly related to the ideal timing and extent of surgery. Further research is needed to define the best surgical strategies in patients with temporal lobe CCMs and structurally normal hippocampi.     

颞叶癫患者的头颅磁共振显像异常表现分析

目的对颞叶癫(TLE)患者头颅磁共振成像(MRI)异常表现进行分析,为临床诊治TLE提供参考。方法对56例TLE患者的头颅MRI异常表现进行分析总结。结果 56例TLE患者头颅MRI主要表现为海马硬化、颞叶软化灶、颞叶肿瘤、颞叶皮质萎缩等。其中,颞叶肿瘤类型多样,主要为少突胶质瘤、星形细胞瘤、脑膜瘤。结论 TLE患者头颅MRI异常表现复杂多样,正确掌握其特点有助于TLE的诊治。