Absence seizures (AS) are generalized non-convulsive seizures characterized by a brief loss of consciousness and spike-and-wave discharges (SWD) in an electroencephalogram (EEG). A number of animal models have been developed to explain the mechanisms of AS, and thalamo-cortical networks are considered to be involved. However, the cortical foci have not been well described in mouse models of AS. This study aims to use a high density EEG in pathophysiologically different AS models to compare the spatiotemporal patterns of SWDs. We used two AS models: a pharmacologically induced model (gamma-hydroxybutyric acid, GHB model) and a transgenic model (phospholipase beta4 knock-out, PLCβ4 model). The occurrences of SWDs were confirmed by thalamic recordings. The topographical analysis of SWDs showed that the onset and propagation patterns were markedly distinguishable between the two models. In the PLCβ4 model, the foci were located within the somatosensory cortex followed by propagation to the frontal cortex, whereas in the GHB model, a majority of SWDs was initiated in the prefrontal cortex followed by propagation to the posterior cortex. In addition, in the GHB model, foci were also observed in other cortical areas. This observation indicates that different cortical networks are involved in the generation of SWDs across the two models.
Animals ; Electroencephalography ; Epilepsy, Absence ; Frontal Lobe ; Mice ; Models, Animal ; Prefrontal Cortex ; Seizures ; Somatosensory Cortex ; Unconsciousness

OBJECTIVE: Previous migraine studies have reported gray matter alterations in various cortical regions with conflicting results. This study aimed to explore a cortical morphometric difference in migraineurs with aura (MA) compared to healthy subjects (HS) and to delineate a possible difference between the cortical morphological features and different aura phenotypes. MATERIALS AND METHODS: Forty-eight MA and 30 HS that were balanced by sex, age, and educational level were selected for this study. T2-weighted and three-dimensional T1-weighted magnetic resonance imaging (MRI) of the brain were acquired using a 1.5T MRI scanner. Surface-based morphometry from the MRI data was used to identify differences between the MA and HS group, and then between MA subgroups. The MA group was subdivided into migraineurs who experienced only visual aura (MVA) and migraineurs who had visual, somatosensory and dysphasic symptoms (MVA+). RESULTS: The MVA+ group had significantly reduced cortical surface area of the left rostral middle frontal cortex compared with the MVA group (p < 0.001). Migraine patients had significantly reduced volume of the left fusiform gyrus relative to HS (p < 0.001). Also, the sulcal depth increased at the level of the left temporal pole in the MVA+ group relative to the MVA group (p < 0.001). The vertex-by-vertex analysis did not exhibit any significant difference in cortical thickness between MA and HS, and between MVA+ and MVA, when corrected for multiple comparisons. CONCLUSION: Migraineurs with aura demonstrates different morphometric features from HS in multiple cortical regions. MVA+ have different morphometric features in the left frontal and temporal lobe relative to MVA, which could be a source of distinct symptoms and serve as potential biomarkers of different MA subtypes.
Aphasia ; Biomarkers ; Brain ; Cerebral Cortex* ; Epilepsy ; Frontal Lobe ; Gray Matter ; Healthy Volunteers ; Humans ; Magnetic Resonance Imaging* ; Migraine Disorders* ; Migraine with Aura* ; Phenotype ; Temporal Lobe

Epilepsy is a chronic neurological disorder, which is not only related to the imbalance between excitatory glutamic neurons and inhibitory GABAergic neurons, but also related to abnormal central cholinergic regulation. This article summarizes the scientific background and experimental data about cholinergic dysfunction in epilepsy from both cellular and network levels, further discusses the exact role of cholinergic system in epilepsy. In the cellular level, several types of epilepsy are believed to be associated with aberrant metabotropic muscarinic receptors in several different brain areas, while the mutations of ionotropic nicotinic receptors have been reported to result in a specific type of epilepsy-autosomal dominant nocturnal frontal lobe epilepsy. In the network level, cholinergic projection neurons as well as their interaction with other neurons may regulate the development of epilepsy, especially the cholinergic circuit from basal forebrain to hippocampus, while cholinergic local interneurons have not been reported to be associated with epilepsy. With the development of optogenetics and other techniques, dissect and regulate cholinergic related epilepsy circuit has become a hotspot of epilepsy research.
Acetylcholine ; physiology ; Basal Forebrain ; pathology ; Brain Chemistry ; genetics ; physiology ; Cholinergic Neurons ; chemistry ; classification ; pathology ; physiology ; Epilepsy ; genetics ; pathology ; physiopathology ; Epilepsy, Frontal Lobe ; genetics ; GABAergic Neurons ; physiology ; Hippocampus ; pathology ; Humans ; Mutation ; genetics ; physiology ; Neurons ; Non-Neuronal Cholinergic System ; genetics ; physiology ; Receptors, Muscarinic ; genetics ; physiology ; Receptors, Nicotinic ; genetics ; physiology ; Synaptic Transmission ; genetics ; physiology

Adult ; Anticonvulsants ; therapeutic use ; Brain ; drug effects ; pathology ; physiopathology ; Carbamazepine ; analogs & derivatives ; therapeutic use ; Electroencephalography ; Epilepsy, Frontal Lobe ; diagnosis ; drug therapy ; Female ; Humans ; Myoclonic Epilepsy, Juvenile ; diagnosis ; drug therapy ; Myoclonus ; diagnosis ; drug therapy

OBJECTIVETo study the clinicopathologic features of tuberous sclerosis complex (TSC).

METHODSThe clinicopathologic data of the patients diagnosed as TSC with refractory epilepsy and resection of epileptic focus were retrospectively analyzed.

RESULTSFourteen cases were included, the mean age was (15.8±12.9) years, with a male predominance (male to female ratio=10:4). Frontal lobe was the most common (13/14) site of involvement. MRI showed multiple patchy long T1 and long T2 signals. CT images showed multiple subependymal high density calcified nodules in nine cases. Histology showed mild to severe disruption of the cortical lamination, cortical and subcortical tubers with giant cells and/or dysmorphic neurons. The giant cells showed strong immunoreactivity for vimentin and nestin, while the dysmorphic neurons partially expressed MAP2 and NF. Vimentin also stained strongly the "reactive" astrocytes. Thirteen cases had follow-up information: Engel class I in six cases, Engel class II in six cases, and Engel class III in one case.

CONCLUSIONSDiagnosis of TSC relies on combined pathologic, clinical and neuroradiological features. Immunohistochemical staining can be helpful. Resection of epileptic focus is an effective method to treat refractory epilepsy in TSC.

Adolescent ; Astrocytes ; chemistry ; pathology ; Child ; Drug Resistant Epilepsy ; surgery ; Epilepsy ; complications ; metabolism ; pathology ; Epilepsy, Frontal Lobe ; complications ; metabolism ; pathology ; Female ; Giant Cells ; chemistry ; pathology ; Humans ; Magnetic Resonance Imaging ; Male ; Nestin ; analysis ; Neurons ; metabolism ; pathology ; Retrospective Studies ; Tuberous Sclerosis ; complications ; metabolism ; pathology ; Vimentin ; analysis

OBJECTIVETo study the changes in 24-hour video electroencephalogram (EEG) and epileptic attacks after levetiracetam add-on therapy in children with frontal lobe epilepsy and epileptiform discharges.

METHODSA prospective study was carried out in 105 children with the frontal lobe epilepsy who received long-term treatment with 1 or 2 types of antiepileptic drug but still with epileptiform discharges in ECG. Levetiracetam add-on therapy was administered at the initial daily dose of 20 mg/kg (given in 2 doses) for 2 weeks followed by an increase of the dose to 30 mg/kg with a maintenance dose of 30-40 mg/kg. The changes in seizure attacks and 24-hour video-EEG monitoring after a 6-month therapy were observed.

RESULTSLevetiracetam add-on therapy reduced epileptiform discharges in 55 children (52.3%) and resulted in significant changes in EEG (P<0.05). Of the 77 children with clinical seizures, complete seizure control was achieved in 12 cases after the therapy, and the seizure attacks were reduced in 28 cases, showing a total response rate of 51.9%; the reduction in seizure attacks was positively correlated with EEG improvement (P<0.001).

CONCLUSIONLevetiracetam add-on therapy can decrease epileptiform discharges in EEG and reduce clinical seizure attacks in children with frontal lobe epilepsy with only mild adverse reactions.

Adolescent ; Anticonvulsants ; administration & dosage ; therapeutic use ; Child ; Child, Preschool ; Electroencephalography ; Epilepsy, Frontal Lobe ; drug therapy ; physiopathology ; Female ; Humans ; Infant ; Male ; Piracetam ; administration & dosage ; analogs & derivatives ; therapeutic use ; Prospective Studies ; Treatment Outcome

OBJECTIVE: Cortical dysplasia (CD) is one of the common causes of epilepsy surgery. However, surgical outcome still remains poor, especially with frontal lobe epilepsy (FLE), despite the advancement of neuroimaging techniques and expansion of surgical indications. The aim of this study was to focus on surgical strategies in terms of extent of resection to improve surgical outcome in the cases of FLE with CD. METHODS: A total of 11 patients of FLE were selected among 67 patients who were proven pathologically as CD, out of a total of 726 epilepsy surgery series since 1992. This study categorized surgical groups into three according to the extent of resection : 1) focal corticectomy, 2) regional corticectomy, and 3) partial functional lobectomy, based on the preoperative evaluation, in particular, ictal scalp EEG onset and/or intracranial recordings, and the lesions in high-resolution MRI. Surgical outcome was assessed following Engel's classification system. RESULTS: Focal corticectomy was performed in 5 patients and regional corticectomy in another set of 5 patients. Only 1 patient underwent partial functional lobectomy. Types I and II CD were detected with the same frequency (45.45% each) and postoperative outcome was fully satisfactory (91%). CONCLUSION: The strategy of epilepsy surgery is to focus on the different characteristics of each individual, considering the extent of real resection, which is based on the focal ictal onset consistent with neuroimaging, especially in the practical point of view of neurosurgery.
Classification ; Electroencephalography ; Epilepsy ; Epilepsy, Frontal Lobe* ; Humans ; Magnetic Resonance Imaging ; Malformations of Cortical Development* ; Neuroimaging ; Neurosurgery ; Scalp

Epileptic nystagmus is defined as a quick, repetitive jerky movement of the eyeball associated with seizure activity. In cases of epileptic nystagmus associated with ictal discharge from multiple brain areas, localization of the exact epileptogenic zone could be extremely difficult. In a nine-year-old patient with epileptic nystagmus and vertigo associated with bilateral temporal and frontal lobe epilepsy, we could infer the epileptic focus by interpreting the patient's clinical picture, characteristics of nystagmus, and findings of electroencephalography.
Brain ; Electroencephalography ; Epilepsy ; Epilepsy, Frontal Lobe* ; Frontal Lobe* ; Humans ; Nystagmus, Pathologic ; Seizures ; Vertigo*

OBJECTIVETo investigate mutations of CHRNA4 gene in Chinese patients with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE).

METHODSTwo hundred and fifty-seven patients (including 215 sporadic and 42 familial cases) were analyzed. Mutational screening was performed by sequencing all of the 6 exons of the CHRNA4 gene including the donor and acceptor splice sites.

RESULTSThe results have excluded the involvement of any known mutations of the CHRNA4 gene. A novel synonymous mutation c.570C>T(D190D) and 6 single nucleotide polymorphisms (SNPs) of the CHRNA4 gene were detected in 6 sporadic cases, including c.639T/C, c.678T/C, c.1209G/T, c.1227T/C, c.1659G/A, and c.1629C/T. The SNP D190D was hererozygous and absent in 200 healthy controls.

CONCLUSIONThis results suggested that mutations of the CHRNA4 gene may be rare in southern Chinese population with ADNFLE. The synonymous mutation D190D has not been reported previously. Its impact on the pathogenesis of ADNFLE warrant further study.

Adolescent ; Adult ; Asian Continental Ancestry Group ; genetics ; Child ; Child, Preschool ; DNA Mutational Analysis ; methods ; Epilepsy, Frontal Lobe ; genetics ; Female ; Genes, Dominant ; Humans ; Infant ; Male ; Mutation ; Pedigree ; Polymorphism, Single Nucleotide ; Receptors, Nicotinic ; genetics ; Young Adult

Non-ketotic hyperglycemia (NKH) is often related to various types of epileptic seizures. However, aphasic seizures associated with NKH have been rarely reported. A 60-year-old diabetic woman was admitted with language disturbance. She presented recurrent motor aphasia and EEG demonstrated ictal rhythmic discharges initiated from left frontal lobe. The seizures disappeared after introduction of carbamazepine and successful control of serum glucose. She remained seizure-free for three months after discharge. We report a case of NKH, manifested by aphasic seizures.
Aphasia, Broca ; Carbamazepine ; Electroencephalography ; Epilepsy ; Female ; Frontal Lobe ; Glucose ; Humans ; Hyperglycemia ; Middle Aged ; Seizures