OBJECTIVETo elucidate the long-term effect of repeated febrile convulsions (FC) on seizure susceptibility in immature rats.

METHODSWarm-water-immersion rat FC model was developed with SD rats 22 days of age, 15 attacks of seizures were induced in the rats every other day, and some of the rats were left un-stimulated for 3 months, then were re-stimulated. Seizure phenomenon was observed, including the latency and the duration of seizures and the temperature of rats. Hippocampal neuron loss and mossy fiber sprouting were detected by thionine staining and Timm staining.

RESULTSAfter the 15th bath, the latency, the duration of seizures, and the temperature of rats were respectively (4.3 +/- 0.8) min, (5.5 +/- 2.9) min, (42.2 +/- 0.7) degrees C. Three months later, on re-stimulation, in 14 of 19 rats with previous FC experience seizures occurred while in only one of 13 non-FC rats seizure occurred and lasted for 8.5 min. Three months later, the latency, the duration of seizures, and the temperature of rats were respectively (5.4 +/- 0.6) min, (19.3 +/- 5.1) min, and (42.4 +/- 0.4) degrees C (4 rats with status epileptics were not included). The incidence of seizures on re-stimulation in rats of FC group (74%) was significantly higher than that in non-FC group (8%) (chi(2) = 13.50, P < 0.01), and the duration of seizures [(19.3 +/- 5.1) min] was significantly longer than those induced in early life [(5.5 +/- 2.9) min] (t = 10.49, P < 0.01). After the 15th bath, no significant change was demonstrated in rats of different groups. While 3 months later, prominent neuron loss was observed in hippocampal CA(3) region in rats with previous FC experience (P < 0.01). Significant mossy fiber sprouting phenomenon was detected after the 15th bath and 3 months later (P < 0.05).

CONCLUSIONRepeated FC in early life enhances long term susceptibility of rats to seizure.

Animals ; Disease Models, Animal ; Disease Susceptibility ; Hippocampus ; pathology ; Rats ; Rats, Sprague-Dawley ; Seizures ; pathology ; Seizures, Febrile ; pathology ; Time Factors

OBJECTIVE: The aim of this study is to compare the frequency of postoperative epilepsies of patients with chronic as opposed to recent onset epilepsy due to glial tumors in the frontal or temporal lobe with the hypothesis that patients with chronic epilepsy do worse. METHODS: We compared the clinical and diagnostic characteristics of the patients(n=73) who had seizures preoperatively to those of the patients(n=153) who did not. Among those who have had seizures preoperatively, we compared those(n=32, chronic seizure group) who had seizures a year or more prior to surgery to those(n=41, acute seizure group) who had seizures within a year prior to surgery. RESULTS: Among the various factors, the frequency of benign pathology and favorable neurological state were higher in seizure group than in non-seizure group(p<0.05). Complex partial seizure and low-grade tumors were frequent in chronic seizure group, whereas simple partial seizure and high-grade tumors were frequent in acute seizure group. Seizure-free rate was significantly higher in acute seizure group than in chronic one(p<0.05). Also, the difference of seizure control rate between surgical strategies were statistically significant(p<0.05). CONCLUSION: This study indicates that preoperative seizure durations and frequencies have a close relationship with the frequency of postoperative epilepsy of glial tumors. A longer lapse may allow the formation of epileptogenic foci, leading to chronic epilepsy, and eventually having a negative effect on the prognosis of the patients. Factors including histopathological characteristics of the tumor, its location, seizure duration/frequency, and semiology should be taken account of deciding on surgical strategies.
Brain Neoplasms ; Epilepsy* ; Glioma ; Humans ; Pathology ; Prognosis ; Seizures ; Temporal Lobe

Patients afflicted with low-grade glioma frequently suffer from seizures. The mechanisms for seizure initiation in these patients remain poorly understood. Tumor location is correlated with seizure initiation. However, these correlative studies rely on dichotomized data analysis which is based on arbitrary lobe assignments. As a result, the lesion-symptom correlation may be incorrectly interpreted. Categorizing patients according to tumor involvement in a single brain lobe might cause the neglect of important information, such as lesion location and lesion volume. Tumors that invaded more than one brain lobe may could be counted repeatedly. The anatomic correlation of the tumor-induced seizures is therefore difficult to be identified. Investigations based on voxel-wise quantitative lesion analysis could avoid the above statistical bias. According to the voxel-wise analysis, the increased seizure risks were identified for patients with low-grade gliomas that involved the left premotor area.
Brain ; pathology ; Brain Neoplasms ; complications ; pathology ; Glioma ; complications ; pathology ; Humans ; Seizures ; etiology

Brain ; pathology ; Humans ; Infant, Newborn ; Lung ; pathology ; Male ; Seizures ; etiology ; pathology ; Tomography, X-Ray Computed ; Tuberous Sclerosis ; complications ; pathology

BACKGROUND: Mesial temporal sclerosis (MTS) is a well-known cause of temporal lobe epilepsy. Coexistence with cortical dysplasia (CD) has been reported, but its role is not well recognized. This study aims to determine whether there is any difference about clinical feature and surgical outcome between patients with MTS and coexistent CD (group 1) and patients with isolated MTS (group 2). METHODS: Retrospectively, surgical series of 45 patients (male:22, female:23) diagnosed as temporal lobe epilepsy were reviewed. We excluded patients who had another pathology (e. g., tumor, vascular malformation) except MTS or CD. The pathology, case histories, interictal EEG, and surgical outcome were compared. RESULTS: There was a tendency for group 1 patients to have earlier seizure onset age (10.9+/-6.35 versus 14.5+/-6.03, p=0.06) There was no statistically significant difference in the history of febrile convulsions (68.4% versus 53.8%, p>0.16) No statistically significant difference between groups were also found in disease duration, the head trauma/mental retardation history, seizure frequency, interictal EEG, and surgical outcome. CONCLUSIONS: CD in MTS appears to have an influence on seizure onset. The relationships among CD, febrile convulsion, and mesial temporal sclerosis must be more investigated.
Age of Onset ; Electroencephalography ; Epilepsy, Temporal Lobe* ; Head ; Humans ; Malformations of Cortical Development* ; Pathology* ; Retrospective Studies ; Sclerosis* ; Seizures ; Seizures, Febrile ; Temporal Lobe*

BACKGROUND: Mesial temporal sclerosis (MTS) is a well-known cause of temporal lobe epilepsy. Coexistence with cortical dysplasia (CD) has been reported, but its role is not well recognized. This study aims to determine whether there is any difference about clinical feature and surgical outcome between patients with MTS and coexistent CD (group 1) and patients with isolated MTS (group 2). METHODS: Retrospectively, surgical series of 45 patients (male:22, female:23) diagnosed as temporal lobe epilepsy were reviewed. We excluded patients who had another pathology (e. g., tumor, vascular malformation) except MTS or CD. The pathology, case histories, interictal EEG, and surgical outcome were compared. RESULTS: There was a tendency for group 1 patients to have earlier seizure onset age (10.9+/-6.35 versus 14.5+/-6.03, p=0.06) There was no statistically significant difference in the history of febrile convulsions (68.4% versus 53.8%, p>0.16) No statistically significant difference between groups were also found in disease duration, the head trauma/mental retardation history, seizure frequency, interictal EEG, and surgical outcome. CONCLUSIONS: CD in MTS appears to have an influence on seizure onset. The relationships among CD, febrile convulsion, and mesial temporal sclerosis must be more investigated.
Age of Onset ; Electroencephalography ; Epilepsy, Temporal Lobe* ; Head ; Humans ; Malformations of Cortical Development* ; Pathology* ; Retrospective Studies ; Sclerosis* ; Seizures ; Seizures, Febrile ; Temporal Lobe*

Clinical, EEG and MRI assessments were conducted in 320 consecutive seizure patients referred to the Yonsei Epilepsy Clinic from october 1, 1991 to Feburary 28. 1993 Clinical assessment suggested that 91.9% of our patients had partial seizures and only 3.1% had generalized seizures. Among partial seizures. Temporal lobe seizure uas considered in 37.5%, localization undetermined partial seizure in 29.7%, extratemporal lobe seizure in 24.7%. Correlation with EEG findings in these patients showed disconcordance rate of 34.6% in generalized seizure, 29.1% in extratemporal lobe seizure, 15.8% in temporal lobe seizure, 5.3% in localization undetermined partial seizure. Structural lesions in MRI were found in 51.6% with hippocampal atrophy being the most frequently round(59.4%). Focal encephalomalacia comprised 15.8%, focal atrophy in 4.8*/o. vascular malformation in 4.2%, granuloma in 3.7%, tumor in 3.7%, cyst in 2.4%. Patients with clinically judged temporal lobe seizure had the most common structural lesions in MRI. Which were seen in 59.2%. Extratemporal lobe seizure had focal lesion in 50.6%. Localization undetermined partial seizure in 50.5%, and generalized seizure in 23.1%. Among 98 patients with hippocampal atrophy, 27 patients(27.6%) had dual pathology with focal encephalomalacia being the most common. 11 patients(11.3%) were suspected to have bilateral hippocampal atrophy. Hippocampal atrophy was more commonly seen in patients with history of febrile convulsion and in patients with severe seizure.
Atrophy ; Electroencephalography* ; Encephalomalacia ; Epilepsy ; Granuloma ; Humans ; Magnetic Resonance Imaging* ; Pathology ; Seizures* ; Seizures, Febrile ; Temporal Lobe ; Vascular Malformations

Anticonvulsants ; therapeutic use ; Child ; China ; Electroencephalography ; Epilepsy ; etiology ; pathology ; therapy ; Humans ; Seizures ; pathology ; therapy

OBJECTIVETo investigate the functional role of hippocampal mossy fiber sprouting in the pathophysiologic mechanism of initiation and propagation of epilepsy.

METHODSThe authors examined hippocampal mossy fiber synaptic reorganization and the changes of hippocampal neurons in P77PMC rats at different stages in the course of recurrent seizures using Timm's method of silver sulfide staining and Nissl staining and observed the effects of recurrent audiogenic seizures (AGSs) on seizure behavior of P77PMC rats.

RESULTSFrequent recurrent AGSs could cause neuronal loss in CA(1) region of hippocampus and hippocampal mossy fiber sprouting got into the inner molecular layer of dentate gyrus in P77PMC rats, and could decrease the latency of IV/V grade of AGSs, increase the durations of AGSs. The mean A of CA(1) region of hippocampus in Nissl staining after 50 times of AGSs was 35.3 +/- 0.8, which was markedly lower than that of the control (44.1 +/- 0.5; F = 333.89, P < 0.001). The mean A of the inner molecular layer of dentate gyrus in Timm's staining after 50 times of AGSs was 49.3 +/- 4.6, which was markedly higher than that of the control (26.8 +/- 1.7; F = 76.83, P < 0.001). After 30 and 50 times of AGSs, the latent periods of IV/V grade of AGSs were 12 +/- 8 (t = 3.805; P < 0.02) and 17 +/- 7 (t = 5.927; P < 0.002) seconds shorter than the initial period of stimulation respectively on average, and the durations of AGSs were 19 +/- 18 (t = 2.644; P < 0.05) and 10 +/- 7 (t = 3.780; P < 0.02) seconds longer.

CONCLUSIONHippocampal mossy fiber sprouting and neuronal loss not only presents in limbic seizure, but also in AGS, the seizure can be initiated in brainstem but rapidly generalized;in AGS-prone rats, recurrent AGSs can cause mossy fiber synaptic reorganization and neuronal loss in hippocampus, and can also enhance seizure susceptibility of P77PMC rats. In the course of recurrent AGSs, enhanced seizure susceptibility happened before hippocampal mossy fiber sprouting. Their temporal relationships indicate that the anatomical changes may be preceded by functional changes of elevated excitability in the brain.

Acoustic Stimulation ; adverse effects ; Animals ; Epilepsy ; pathology ; Mossy Fibers, Hippocampal ; pathology ; Rats ; Rats, Wistar ; Seizures ; etiology ; pathology

Objective: To investigate clinicopathological features of multinodular and vacuolar neurodegenerative tumor (MVNT) of the cerebrum, and to investigate its immunophenotype, molecular characteristics and prognosis. Methods: Four cases were collected at the General Hospital of Southern Theater Command, Guangzhou, China and one case was collected at the First People's Hospital of Huizhou, China from 2013 to 2021. Clinical, histological, immunohistochemical and molecular characteristics of these five cases were analyzed. Follow-up was carried out to evaluate their prognoses. Results: There were four females and one male, with an average age of 42 years (range, 17 to 51 years). Four patients presented with seizures, while one presented with discomfort on the head. Pre-operative imaging demonstrated non-enhancing, T2-hyperintense multinodular lesions in the deep cortex and superficial white matter of the frontal (n=1) or temporal lobes (n=4). Microscopically, the tumor cells were mostly arranged in discrete and coalescent nodules primarily within the deep cortical ribbon and superficial subcortical white matter. The tumors were composed of large cells with ganglionic morphology, vesicular nuclei, prominent nucleoli and amphophilic or lightly basophilic cytoplasm. They exhibited varying degrees of matrix vacuolization. Vacuolated tumor cells did not show overt cellular atypia or any mitotic activities. Immunohistochemically, tumor cells exhibited widespread nuclear staining for the HuC/HuD neuronal antigens, SOX10 and Olig2. Expression of other neuronal markers, including synaptophysin, neurofilament and MAP2, was patchy to absent. The tumor cells were negative for NeuN, GFAP, p53, H3K27M, IDH1 R132H, ATRX, BRG1, INI1 and BRAF V600E. No aberrant molecular changes were identified in case 3 and case 5 using next-generation sequencing (including 131 genes related to diagnosis and prognosis of central nervous system tumors). All patients underwent complete or substantial tumor excision without adjuvant chemoradiotherapy. Post-operative follow-up information over intervals of 6 months to 8 years was available for five patients. All patients were free of recurrence. Conclusions: MVNT is an indolent tumor, mostly affecting adults, which supports classifying MVNT as WHO grade 1. There is no tumor recurrence even in the patients treated with subtotal surgical excision. MVNTs may be considered for observation or non-surgical treatments if they are asymptomatic.
Adult ; Female ; Humans ; Male ; Brain Neoplasms/pathology* ; Cerebrum/pathology* ; Neurons/metabolism* ; Seizures ; Temporal Lobe/pathology* ; Biomarkers, Tumor/metabolism*