This study reports the prevalence of Nonconvulsive Status Epilepticus (NCSE) in patients with altered mental status (AMS), and describes the clinical presentation, etiology, neurophysiological findings, neuroimaging, treatment, and outcome of NCSE in Qatar. Recording duration of continuous EEG monitoring was also discussed. This was a 3-year, prospective, hospital-based study involving patients with AMS and continuous EEG monitoring admitted to the Emergency and ICUs of Hamad Hospital, Qatar.
View Article and Find Full Text PDFLimbic encephalitis (LE) with waxing and waning neuropsychiatric manifestations including behavioral, personality, psychiatric, and memory changes can evolve over days to months. Many features of LE show remarkable overlap with the characteristics of mesial-temporal (limbic) status epilepticus (MTLSE or LSE). With LE, these prolonged impaired states are assumed not to be due to ongoing epileptic activity or MTLSE, because scalp EEGs usually show no epileptiform spike-wave activity; cycling behavioral and motor changes are attributed to LE; there may be little immediate improvement with antiepileptic drugs (AEDs); and of course, implanted electrodes are rarely used.
View Article and Find Full Text PDFOne of the main putative causes of therapy refractory epilepsy in mesial temporal lobe epilepsy (MTLE) with hippocampal sclerosis is the overexpression of multidrug transporters (MDTs) at the blood-brain barrier (BBB). It steps up the removal of antiepileptic drugs (AEDs) out of the brain cells across the BBB resulting in a low concentration of AEDs within the target cells. Some of the mechanisms of AED resistance are most likely to be genetically determined.
View Article and Find Full Text PDFPartial epilepsies have a substantial heritability. However, the actual genetic causes are largely unknown. In contrast to many other common diseases for which genetic association-studies have successfully revealed common variants associated with disease risk, the role of common variation in partial epilepsies has not yet been explored in a well-powered study.
View Article and Find Full Text PDFDeletions at 16p13.11 are associated with schizophrenia, mental retardation, and most recently idiopathic generalized epilepsy. To evaluate the role of 16p13.
View Article and Find Full Text PDFMapping the distribution of GABAA receptor subtypes represents a promising approach to characterize alterations in cortical circuitry associated with neurological disorders. We previously reported subtype-selective changes in GABAA receptor expression in the grey matter of patients with focal epilepsy. In the present follow-up study, we focused on the subcortical white matter in the same tissue specimens obtained at surgery from 9 patients with temporal lobe epilepsy (TLE) and hippocampal sclerosis, 12 patients with TLE associated with neocortical lesions and 5 patients with frontal lobe epilepsy; post-mortem tissue from 4 subjects served as controls.
View Article and Find Full Text PDFImpaired transmission in GABAergic circuits is thought to contribute to the pathogenesis of epilepsy. Although it is well established that major reorganization of GABA(A) receptor subtypes occurs in the hippocampus of patients with medically refractory temporal lobe epilepsy (TLE), it is unclear whether this disorder is also associated with alterations in GABA(A) receptor subtypes in the neocortex. Here we have investigated immunohistochemically the subunit composition and neocortical distribution of three major GABA(A) receptor subtypes using antibodies specifically recognizing the subunits alpha1, alpha2, alpha3, beta2/3 and gamma2.
View Article and Find Full Text PDFObjective: We have investigated intracerebral propagation of interictal epileptiform discharges (IED) in patients with mesial temporal lobe epilepsy (MTLE) by using spatiotemporal source maps based on statistical nonparametric mapping (SNPM) of low resolution electromagnetic tomography (LORETA) values.
Methods: We analyzed 30 patterns of IED recorded simultaneously with scalp and intracranial foramen ovale (FO) electrodes in 15 consecutive patients with intractable MTLE. The scalp EEG signals were averaged time-locked to the peak activity in bilateral 10-contact FO electrode recordings.
Iron is a central element in the metabolism of normal and malignant cells. Abnormalities in iron and ferritin expression have been observed in many types of cancer. Interest in characterizing iron compounds in the human brain has increased due to advances in determining a relationship between excess iron accumulation and neurological and neurodegenerative diseases.
View Article and Find Full Text PDFElectroecenphalography (EEG) is an integral part of the diagnostic process in patients with Creutzfeldt-Jakob disease (CJD). The EEG has therefore been included in the World Health Organisation diagnostic classification criteria of CJD. In sporadic CJD (sCJD), the EEG exhibits characteristic changes depending on the stage of the disease, ranging from nonspecific findings such as diffuse slowing and frontal rhythmic delta activity (FIRDA) in early stages to disease-typical periodic sharp wave complexes (PSWC) in middle and late stages to areactive coma traces or even alpha coma in preterminal EEG recordings.
View Article and Find Full Text PDFObjective: To investigate the localization accuracy of low-resolution electromagnetic tomography (LORETA) for mesial temporal interictal epileptiform discharges (IED) using a new relative averaging (RELAVG) technique for noise reduction.
Methods: We analyzed 19 patterns of mesial temporal IED recorded simultaneously with scalp and foramen ovale (FO) electrodes in 15 consecutive patients who underwent presurgical assessment for intractable temporal lobe epilepsy. The scalp signals were time-locked to the peak activity in the FO electrode recordings and source modeling was performed using the RELAVG technique.
Focal beta activity on scalp EEG is a rare seizure pattern that has most extensively been studied in patients undergoing evaluation for epilepsy surgery. However, ictal beta activity is uncommon beyond this population and has not been reported in human status epilepticus. We observed ictal focal beta activity as the predominant seizure pattern in a patient with refractory status epilepticus.
View Article and Find Full Text PDFObjective: We studied the relation between thalamic stimulation parameters and the morphology, topographic distribution and cortical sources of the cerebral responses in patients with intractable epilepsy undergoing deep brain stimulation (DBS) of the thalamus.
Methods: Bipolar and monopolar stimuli were delivered at a rate of 2 Hz to the anterior (AN, four patients), the dorsomedian (DM, four patients), and the centromedian nucleus (CM, one patient) using the programmable stimulation device (Medtronic ITREL II). Source modeling was carried out by using statistical non-parametric mapping of low-resolution electromagnetic tomography (LORETA) values.
Multidrug resistance protein, also referred as P-glycoprotein (P-gp, MDR1; ABCB1) and multidrug resistance-associated protein (MRP) 1 (ABCC1) and 2 (ABCC2) are, thus far, candidates to cause antiepileptic drug (AED) resistance epilepsy. In this study, we investigated P-gp, MRP1 and MRP2 expression, localization and functional activity on cryosections and isolated human brain-derived microvascular endothelial cells (HBMEC) from epileptic patients (HBMEC-EPI) with hippocampal sclerosis (HS), as compared with HBMEC isolated from normal brain cortex (HBMEC-CTR). We examined the expression and distribution of three transporters, P-gp, MRP1 and MRP2 on two major parts of the resected tissue, the hippocampus and the parahippocampal gyrus (Gph).
View Article and Find Full Text PDFIctal vomiting in patients with focal epilepsy has mostly been associated with an epileptogenic zone in the non-language-dominant hemisphere. Here we present the case of a left hemisphere language-dominant patient suffering from typical mesial temporal lobe epilepsy with histologically proven hippocampal sclerosis and ictal vomiting during complex partial seizures. He became seizure-free after selective left-sided amygdalohippocampectomy.
View Article and Find Full Text PDFObjective: We have investigated the localization accuracy of low-resolution electromagnetic tomography (LORETA) for mesial temporal interictal epileptiform discharges (IED) on a statistical basis by using clinical electroencephalographic (EEG) data of simultaneous scalp and intracranial foramen ovale (FO) electrode recordings.
Methods: We retrospectively analyzed the IED of 15 patients who underwent presurgical assessment for intractable temporal lobe epilepsy. All patients have subsequently undergone amygdalohippocampectomy.
Awake surgery was performed in a series of 21 patients with gliomas in eloquent areas with the use of intraoperative electrical mapping. Gross total removal was performed in 18 patients. There was no operative mortality.
View Article and Find Full Text PDFPurpose: To further evaluate the safety, efficacy and optimal dose of levetiracetam (LEV) in daily clinical practice among patients with uncontrolled partial epilepsy with or without secondary generalization.
Methods: In this phase IV, open-label, 16-week community-based study, 178 at least 16-year-old patients with refractory focal epilepsy were treated with 1000, 2000 or 3000 mg levetiracetam as adjunctive therapy. All patients started with 500 mg LEV b.
Background And Aims: To describe an unusual clinical presentation of a patient with voltage-gated potassium channel Ab- positive, non-paraneoplastic limbic encephalitis.
Methods: We performed video-EEG monitoring, structural MRI, (18)F-FDG-PET, (1)H-MRS, neuropsychological testing and antibody serology.
Results: A 42-year-old male patient presented in an acute phase of non-paraneoplastic limbic encephalitis confirmed by MRI, with antibodies to voltage-gated potassium channels.
Excess iron accumulation in the brain has been shown to be related to a variety of neurodegenerative diseases. However, identification and characterization of iron compounds in human tissue is difficult because concentrations are very low. For the first time, a combination of low temperature magnetic methods was used to characterize iron compounds in tumour tissue from patients with mesial temporal lobe epilepsy (MTLE).
View Article and Find Full Text PDFUnlabelled: Retrospectively we analysed postoperative AED treatment in patients with mesial temporal lobe epilepsy and hippocampal sclerosis (MTLE-HS) who were seizure free following selective amygdalohippocampectomy (AHE). In this subgroup, we compared the patients without AEDs with that in the entire series.
Results: During the year prior to surgery, in the MTLE-HS group, a mean of 2.
Objective: To study temporal and spatial development of EEG patterns in sporadic and iatrogenic Creutzfeldt-Jakob disease patients.
Methods: Temporal and spatial development of EEG patterns in 4 patients with sporadic Creutzfeldt-Jakob disease and 2 patients with iatrogenic Creutzfeldt-Jakob disease due to implantation of contaminated brain depth electrodes were investigated. A total of 56 EEGs were analyzed, over time spans ranging from 1272 to 3 days prior to death.
Ferromagnetic transduction models have been proposed as a potential mechanism for mobile phone bioeffects. These models are based on the coupling of RF and pulsed electromagnetic emissions to biogenic magnetite (Fe3O4) present in the human brain via either ferromagnetic resonance or mechanical activation of cellular ion channels. We have tested these models experimentally for the first time using a bacterial analogue (Magnetospirillum magnetotacticum) which produces intracellular biogenic magnetite similar to that present in the human brain.
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