scholarly journals The relationship of bioelectric activity and structural changes in the hippocampus at pharmacoresistant temporal lobe epilepsy

2021 ◽  
Vol 8 (2) ◽  
pp. 5-13
Author(s):  
E. A. Astakhova ◽  
S. E. Cherenkova ◽  
E. V. Marchenko ◽  
K. I. Sebelev ◽  
M. V. Aleksandrov
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Structural Damage ◽  
Structural Changes ◽  
Bioelectrical Activity ◽  
Bioelectric Activity ◽  
Temporal Lobes ◽  
Hippocampal Activity ◽  
Drug Resistant Epilepsy ◽  
Hippocampal Complex

Background. Epilepsy is one of the most common neurological diseases globally. The unified concept about the role of hippocampus in the development of pharmacoresistant temporal lobe epilepsy is currently missing. Patients with pharmacoresistant temporal lobe epilepsy is often carried out by invasive electrocorticography to identify an epileptic focus. Registration of bioelectric activity of the hippocampus and comparison of data from the MRI pattern of the patient will determine the neurophysiological correlates of structural changes in hippocampus.Objective. The aim of the work was to determine the neurophysiological correlates of structural changes in the hippocampus in patients with focally caused temporal lobe epilepsy.Design and methods. The study was based on the analysis of the results of extraoperative invasive monitoring of the bioelectrical activity of the cortex and hippocampal complex, performed in 19 patients with focally caused drug-resistant epilepsy. The quantitative analysis included 34 tracks of hippocampal activity.Results. A distinctive feature of the bioelectrical activity of the hippocampal complex with its structural damage is the stable dominance of delta activity, which makes up 40–45 % of the total spectrum power. When the hippocampal complex is included in the epileptic system, high-index epileptiform activity is recorded. In the absence of structural damage to the hippocampal complex, the pattern is predominantly formed by the activity of theta and alpha frequency ranges. However, in the group of patients with the absence of a neuroimaging picture of sclerotic changes in the hippocampus, in 63 % of cases, a neurophysiological pattern of “prolapse” was recorded on the electrocorticogram. The spontaneous activity of the hippocampus had a low coherent relationship with the parameters of activity in the cortex of the ipsilateral and contralateral temporal lobes.Conclusions. The electrophysiological correlate of MR-positive structural changes in the hippocampal complex in drug-resistant epilepsy is the pattern of “loss of bioelectric activity”. Spontaneous hippocampal activity is generated independently of activity in the cortex of the ipsilateral and contralateral temporal lobes.

Structural changes in astrocytes induced by seizures in a model of temporal lobe epilepsy

1990 ◽  
Vol 26 (3) ◽  
pp. 334-341 ◽  
Author(s):  
A. J. Castiglioni ◽  
S. L. Peterson ◽  
E. L. Sanabria ◽  
E. Tiffany-Castiglioni
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Structural Changes

Understanding the association of neurocysticercosis and mesial temporal lobe epilepsy and its impact on the surgical treatment of patients with drug-resistant epilepsy

2017 ◽  
Vol 76 ◽  
pp. 168-177 ◽  
Author(s):  
Marino Muxfeldt Bianchin ◽  
Tonicarlo Rodrigues Velasco ◽  
Lauro Wichert-Ana ◽  
Antonio Carlos dos Santos ◽  
Américo Ceiki Sakamoto
Keyword(s):  
Surgical Treatment ◽  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Mesial Temporal Lobe Epilepsy ◽  
Drug Resistant ◽  
Mesial Temporal Lobe ◽  
Drug Resistant Epilepsy

scholarly journals Gambaran penyandang epilepsi berdasarkan ILAE 1989 di Poliklinik Saraf RSUP Prof. Dr. R. D. Kandou Manado tahun 2014

e-CliniC ◽  
2016 ◽  
Vol 4 (1) ◽  
Author(s):  
Patrick G. Tendean ◽  
Winifred . Karema ◽  
Arthur . Mawuntu
Keyword(s):  
Retrospective Study ◽  
Temporal Lobe Epilepsy ◽  
Medical Record ◽  
Temporal Lobe ◽  
Temporal Lobes ◽  
Epileptic Patients ◽  
Using Data

Abstrak: Epilepsy is commonly found in the community. This study aimed to obtain the profile of epileptic patients at Prof Dr. R. D. Kandou Hospital Manado in 2014. This was a descriptive retrospective study using data of Department of Medical Record Prof. Dr. R. D. Kandou Hospital Manado 2014. The results showed that there were 144 subjects that fulfilled the criteria; 81 (56.3%) of them were males. Most of them were at the age 15-24 years, had profession as students, and were diagnosed as temporal lobe epilepsy EEG was performed on 35 subjects; 13 of them had lesion in the temporal lobes. Nearly half of the subjects were treated with phenytoin.Kata kunci: epilepsi, temporal, phenytoin Abstrak: Epilepsi merupakan penyakit yang sering ditemukan di masyarakat. Penelitian ini bertujuan untuk mengetahui gambaran penyandang epilepsi di RSUP Prof. Dr. R. D. Kandou Manado pada tahun 2014. Jenis penelitian ini deskriptif retrospektif dengan memanfaatkan data dari Bagian Rekam Medik RSUP Prof. Dr. R. D. Kandou Manado tahun 2014. Hasil penelitian memperlihatkan sebanyak 144 subjek yang memenuhi kriteria penelitian. Terdapat 81 subjek (56,3%) berjenis kelamin laki-laki. Golongan usia terbanyak ialah 15-24 tahun, sebagian besar berprofesi sebagai pelajar/mahasiswa, dan paling banyak terdiagnosis sebagai epilepsi lobus temporal. EEG dikerjakan pada 35 subjek; sebanyak 13 subjek memiliki letak lesi di lobus temporal. Hampir setengah dari keseluruhan subjek menggunakan terapi phenytoin. Kata kunci: epilepsi, temporal, phenytoin

scholarly journals Seizure Freedom After Epilepsy Surgery and Higher Baseline Cognition May Be Associated With a Negatively Correlated Epilepsy Network in Temporal Lobe Epilepsy

2021 ◽  
Vol 14 ◽  
Author(s):  
Elliot G. Neal ◽  
Mike R. Schoenberg ◽  
Stephanie Maciver ◽  
Yarema B. Bezchlibnyk ◽  
Fernando L. Vale
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Epilepsy Surgery ◽  
Memory Function ◽  
Brain Regions ◽  
Seizure Freedom ◽  
Epileptogenic Zone ◽  
Temporal Lobes ◽  
Scalp Eeg ◽  
The Brain

Background: Brain regions positively correlated with the epileptogenic zone in patients with temporal lobe epilepsy vary in spread across the brain and in the degree of correlation to the temporal lobes, thalamus, and limbic structures, and these parameters have been associated with pre-operative cognitive impairment and seizure freedom after epilepsy surgery, but negatively correlated regions have not been as well studied. We hypothesize that connectivity within a negatively correlated epilepsy network may predict which patients with temporal lobe epilepsy will respond best to surgery.Methods: Scalp EEG and resting state functional MRI (rsfMRI) were collected from 19 patients with temporal lobe epilepsy and used to estimate the irritative zone. Using patients’ rsfMRI, the negatively correlated epilepsy network was mapped by determining all the brain voxels that were negatively correlated with the voxels in the epileptogenic zone and the spread and average connectivity within the network was determined.Results: Pre-operatively, connectivity within the negatively correlated network was inversely related to the spread (diffuseness) of that network and positively associated with higher baseline verbal and logical memory. Pre-operative connectivity within the negatively correlated network was also significantly higher in patients who would go on to be seizure free.Conclusion: Patients with higher connectivity within brain regions negatively correlated with the epilepsy network had higher baseline memory function, narrower network spread, and were more likely to be seizure free after surgery.

scholarly journals P.035 Correlation of thalamic connectivity with the duration of epilepsy in patients with temporal lobe epilepsy

2017 ◽  
Vol 44 (S2) ◽  
pp. S22-S22
Author(s):  
B Santyr ◽  
JC Lau ◽  
SM Mirsattari ◽  
JG Burneo ◽  
S de Ribaupierre ◽  
...  
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Surgical Outcomes ◽  
Parahippocampal Gyrus ◽  
Probabilistic Tractography ◽  
Temporal Lobes ◽  
Surgical Success ◽  
False Discovery ◽  
Long Duration ◽  
Temporal Neocortex

Background: Morphometry and connectivity studies targeting the thalamus have revealed specific patterns of atrophy and deafferentiation in patients with temporal lobe epilepsy (TLE). We used probabilistic tractography to investigate thalamic connectivity with respect to duration of epilepsy and surgical outcomes in TLE. Methods: Patients (N=20) with drug-resistant TLE (10 short duration (<15 years), 10 long duration (>15 years)) were scanned with multi-parametric 3T MRI and compared with 34 healthy controls. The Harvard-Oxford atlas was modified to create 14 target regions in the temporal lobes. Probabilistic tractography (FSL) was used to delineate thalamic sub-regions most connected to each target. The volume, mean T1, T2, FA and MD of each thalamic sub-region was quantified. Surgical success was quantified using Engel outcome scores. Results: Significant decreases in thalamic connected volumes to the hippocampus in patients with longer duration of TLE were revealed. Likewise, when stratified based on surgical success, significant differences in diffusion metrics to the hippocampus, parahippocampal gyrus, and temporal neocortex were found. Significant differences did not withstand false discovery rate (FDR) correction. Conclusions: These findings suggest ongoing connectivity changes dependent on epilepsy duration and promote further investigation into the use of thalamic connectivity data as biomarkers for predicting surgical outcomes in TLE patients.

scholarly journals Preoperative Electroencephalographic Localization of Large Epileptogenic Zones in the Frontal and Temporal Lobes

1991 ◽  
Vol 18 (S4) ◽  
pp. 564-565 ◽  
Author(s):  
Cosimo Ajmone-Marsan
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Frontal Lobe ◽  
Temporal Lobe ◽  
Cortical Neurons ◽  
Frontal Lobe Epilepsy ◽  
Epileptogenic Zone ◽  
Large Area ◽  
Temporal Lobes ◽  
Concentric Circles

ABSTRACT:The concept of epileptogenic zone is defined as a large area of cortical neurons arranged in concentric circles of variable degrees of epileptogenicity. This is particularly so in frontal lobe epilepsy since the interictal and ictal epileptic abnormalities are poorly localized, often absent and at times misleading in terms of localization. In temporal lobe epilepsy, the epileptogenic zones may be more restricted.

scholarly journals Depression and temporal lobe epilepsy represent an epiphenomenon sharing similar neural networks: clinical and brain structural evidences

2013 ◽  
Vol 71 (3) ◽  
pp. 183-190 ◽  
Author(s):  
Kette D. R. Valente ◽  
Geraldo Busatto Filho
Keyword(s):  
Neural Networks ◽  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Mesial Temporal Lobe Epilepsy ◽  
Structural Basis ◽  
Mesial Temporal Sclerosis ◽  
Subcortical Structures ◽  
Temporal Lobes ◽  
Ancient Times ◽  
The Relationship

The relationship between depression and epilepsy has been known since ancient times, however, to date, it is not fully understood. The prevalence of psychiatric disorders in persons with epilepsy is high compared to general population. It is assumed that the rate of depression ranges from 20 to 55% in patients with refractory epilepsy, especially considering those with temporal lobe epilepsy caused by mesial temporal sclerosis. Temporal lobe epilepsy is a good biological model to understand the common structural basis between depression and epilepsy. Interestingly, mesial temporal lobe epilepsy and depression share a similar neurocircuitry involving: temporal lobes with hippocampus, amygdala and entorhinal and neocortical cortex; the frontal lobes with cingulate gyrus; subcortical structures, such as basal ganglia and thalamus; and the connecting pathways. We provide clinical and brain structural evidences that depression and epilepsy represent an epiphenomenon sharing similar neural networks.

A NOVEL LGI1 VARIANT IN LATERAL TEMPORAL LOBE EPILEPSY

2015 ◽  
Vol 86 (11) ◽  
pp. e4.154-e4
Author(s):  
WO Pickrell ◽  
CHD Hope ◽  
AT Higgins ◽  
JGL Mullins ◽  
PEM Smith ◽  
...  
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Protein Function ◽  
Structural Changes ◽  
Family Members ◽  
In Silico Analysis ◽  
Structural Effect ◽  
Protein Modelling ◽  
Novel Variant ◽  
Control Samples

BackgroundWe identified a family with autosomal dominant lateral temporal lobe epilepsy (ADLTLE). Given that LGI1 mutations account for around 50% of families with ADLTLE, we screened family members for LGI1 variants.MethodWe sequenced all exonic regions of LGI1 and used in-silico analysis tools to assess the potential affect of the novel variant. We screened 106 control samples for the variant and assessed the structural effect of the variant using a protein modelling platform.ResultsThe proband's seizures consist of an unilateral ‘buzzing’ sensation which progresses to unilateral limb numbness and secondarily generalised seizures. Some noises can provoke seizures. Her mother also has epilepsy with identical seizure semiology. We identified a novel heterozygous missense LGI1 variant in the proband and her mother which was not present in other family members or control samples. This variant is close to the splice site region of LGI1 exon 4 and is predicted to be deleterious. Protein modelling suggests that the variant causes conformational structural changes.ConclusionWe present a family with ADLTLE caused by a novel variant in LGI1. This variant is predicted to be deleterious, alters protein function and adds additional evidence for the role of LGI1 in ADLTLE.

scholarly journals Structural Abnormalities are Similar in Familial and Nonfamilial Mesial Temporal Lobe Epilepsy

2004 ◽  
Vol 31 (3) ◽  
pp. 368-372 ◽  
Author(s):  
Fabio Thadeu Ferreira ◽  
Eliane Kobayashi ◽  
Iscia Lopes-Cendes ◽  
Fernando Cendes
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Visual Analysis ◽  
Mesial Temporal Lobe Epilepsy ◽  
Control Group ◽  
Hippocampal Atrophy ◽  
Anterior Temporal Lobe ◽  
Temporal Lobes ◽  
Mesial Temporal Lobe ◽  
Lobe Atrophy

Background/Objective:Diffuse temporal lobe abnormalities can be observed on MRI of patients with mesial temporal lobe epilepsy (MTLE). Our objective was to perform qualitative and quantitative analyses of temporal lobe structures in patients with familial MTLE (FMTLE) and nonfamilial MTLE.Methods:Two groups of patients were ascertained: 67 FMTLE patients (14 with refractory seizures) and 30 patients with nonfamilial refractory MTLE. We performed qualitative analyses of MRI (with multiplanar reconstruction) and volumes of hippocampi and anterior temporal lobes in all patients, and in a normal control group of 23 individuals. We used the Chi-square test and ANOVA for statistical analyses.Results:We identified anterior temporal lobe abnormalities by visual analysis in only 4% of FMTLE patients and atrophy of the anterior temporal lobe by volumetric analysis in 19%. In the group of nonfamilial MTLE patients we found anterior temporal lobe abnormalities by visual analysis in 17% of patients and anterior temporal lobe atrophy in 13%. Hippocampal atrophy was present in 90% of FMTLE and in 83% of nonfamilial MTLE. No signs of cortical dysplasia were observed.Conclusion:Anterior temporal lobe atrophy and other abnormalities outside the mesial portion of temporal lobes were infrequent in both familial and nonfamilial MTLE patients. Despite the genetic basis, hippocampal atrophy in FMTLE is not associated with other abnormalities outside the mesial temporal regions.

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