ABSTRACT
OBJECTIVE: Genetic generalized epilepsy (GGE) accounts for approximately 20% of adult epilepsy cases and is considered a disorder of large brain networks, involving both hemispheres. Most studies have not shown any difference in functional whole-brain network topology when compared to healthy controls. Our objective was to examine whether this preserved global network topology could hide local reorganizations that balance out at the global network level. METHODS: We recorded high-density electroencephalograms from 20 patients and 20 controls, and reconstructed the activity of 118 regions. We computed functional connectivity in windows free of interictal epileptiform discharges in broad, delta, theta, alpha, and beta frequency bands, characterized the network topology, and used the Hub Disruption Index (HDI) to quantify the topological reorganization. We examined the generalizability of our results by reproducing a 25-electrode clinical system. RESULTS: Our study did not reveal any significant change in whole-brain network topology among GGE patients. However, the HDI was significantly different between patients and controls in all frequency bands except alpha (p < .01, false discovery rate [FDR] corrected, d < -1), and accompanied by an increase in connectivity in the prefrontal regions and default mode network. This reorganization suggests that regions that are important in transferring the information in controls were less so in patients. Inversely, the crucial regions in patients are less so in controls. These findings were also found in delta and theta frequency bands when using 25 electrodes (p < .001, FDR corrected, d < -1). SIGNIFICANCE: In GGE patients, the overall network topology is similar to that of healthy controls but presents a balanced local topological reorganization. This reorganization causes the prefrontal areas and default mode network to be more integrated and segregated, which may explain executive impairment associated with GGE. Additionally, the reorganization distinguishes patients from controls even when using 25 electrodes, suggesting its potential use as a diagnostic tool.
Subject(s)
Epilepsy, Generalized , Epilepsy , Adult , Humans , Nerve Net/diagnostic imaging , Brain/diagnostic imaging , Electroencephalography/methods , Brain Mapping , Epilepsy, Generalized/genetics , Magnetic Resonance Imaging/methodsABSTRACT
BACKGROUND: Several studies found that patients with new-onset epilepsy (NOE) have higher seizure recurrence rates if they presented already prior seizures. These observations suggest that timing of antiseizure medication (ASM) is crucial and should be offered immediately after the first seizure. Here, we wanted to assess whether immediate ASM is associated with improved outcome. METHODS: Single-center study of 1010 patients (≥16 years) who presented with a possible first seizure in the emergency department between 1 March 2010 and 1 March 2017. A comprehensive workup was launched upon arrival, including routine electroencephalography (EEG), brain computed tomography/magnetic resonance imaging, long-term overnight EEG and specialized consultations. We followed patients for 5 years comparing the relapse rate in patients treated within 48 h to those with treatment >48 h. RESULTS: A total of 487 patients were diagnosed with NOE. Of the 416 patients (162 female, age: 54.6 ± 21.1 years) for whom the treatment start could be retrieved, 80% (333/416) were treated within 48 h. The recurrence rate after immediate treatment (32%; 107/333) was significantly lower than in patients treated later (56.6%; 47/83; p < 0.001). For patients for whom a complete 5-year-follow-up was available (N = 297, 123 female), those treated ≤48 h (N = 228; 76.8%) had a significantly higher chance of remaining seizure-free compared with patients treated later (N = 69; 23.2%; p < 0.001). CONCLUSIONS: In this retrospective study, immediate ASM therapy (i.e., within 48 h) was associated with better prognosis up to 5 years after the index event. Prospective studies are required to determine the value of immediate workup and drug therapy in NOE patients.
Subject(s)
Epilepsy , Humans , Female , Adult , Middle Aged , Aged , Retrospective Studies , Epilepsy/diagnosis , Seizures/diagnosis , Prognosis , Magnetic Resonance Imaging , ElectroencephalographyABSTRACT
BACKGROUND AND PURPOSE: Alcohol withdrawal seizures (AWS) are a well-known complication of chronic alcohol abuse, but there is currently little knowledge of their long-term relapse rate and prognosis. The aims of this study were to identify risk factors for AWS recurrence and to study the overall outcome of patients after AWS. METHODS: In this retrospective single-center study, we included patients who were admitted to the Emergency Department after an AWS between January 1, 2013 and August 10, 2021 and for whom an electroencephalogram (EEG) was requested. AWS relapses up until April 29, 2022 were researched. We compared history, treatment with benzodiazepines or antiseizure medications (ASMs), laboratory, EEG and computed tomography findings between patients with AWS relapse (r-AWS) and patients with no AWS relapse (nr-AWS). RESULTS: A total of 199 patients were enrolled (mean age 53 ± 12 years; 78.9% men). AWS relapses occurred in 11% of patients, after a median time of 470.5 days. Brain computed tomography (n = 182) showed pathological findings in 35.7%. Risk factors for relapses were history of previous AWS (p = 0.013), skull fractures (p = 0.004) at the index AWS, and possibly epileptiform EEG abnormalities (p = 0.07). Benzodiazepines or other ASMs, taken before or after the index event, did not differ between the r-AWS and the nr-AWS group. The mortality rate was 2.9%/year of follow-up, which was 13 times higher compared to the general population. Risk factors for death were history of AWS (p < 0.001) and encephalopathic EEG (p = 0.043). CONCLUSIONS: Delayed AWS relapses occur in 11% of patients and are associated with risk factors (previous AWS >24 h apart, skull fractures, and pathological EEG findings) that also increase the epilepsy risk, that is, predisposition for seizures, if not treated. Future prospective studies are mandatory to determine appropriate long-term diagnostic and therapeutic strategies, in order to reduce the risk of relapse and mortality associated with AWS.
Subject(s)
Alcohol Withdrawal Seizures , Alcoholism , Skull Fractures , Substance Withdrawal Syndrome , Male , Humans , Adult , Middle Aged , Aged , Female , Alcohol Withdrawal Seizures/complications , Alcohol Withdrawal Seizures/chemically induced , Alcohol Withdrawal Seizures/drug therapy , Alcoholism/complications , Substance Withdrawal Syndrome/complications , Substance Withdrawal Syndrome/drug therapy , Retrospective Studies , Prospective Studies , Benzodiazepines/therapeutic use , Recurrence , Skull Fractures/chemically induced , Skull Fractures/complications , Skull Fractures/drug therapyABSTRACT
OBJECTIVE: This study was undertaken to establish whether advanced workup including long-term electroencephalography (LT-EEG) and brain magnetic resonance imaging (MRI) provides an additional yield for the diagnosis of new onset epilepsy (NOE) in patients presenting with a first seizure event (FSE). METHODS: In this population-based study, all adult (≥16 years) patients presenting with FSE in the emergency department (ED) between March 1, 2010 and March 1, 2017 were assessed. Patients with obvious nonepileptic or acute symptomatic seizures were excluded. Routine EEG, LT-EEG, brain computed tomography (CT), and brain MRI were performed as part of the initial workup. These examinations' sensitivity and specificity were calculated on the basis of the final diagnosis after 2 years, along with the added value of advanced workup (MRI and LT-EEG) over routine workup (routine EEG and CT). RESULTS: Of the 1010 patients presenting with FSE in the ED, a definite diagnosis of NOE was obtained for 501 patients (49.6%). Sensitivity of LT-EEG was higher than that of routine EEG (54.39% vs. 25.5%, p < .001). Similarly, sensitivity of MRI was higher than that of CT (67.98% vs. 54.72%, p = .009). Brain MRI showed epileptogenic lesions in an additional 32% compared to brain CT. If only MRI and LT-EEG were considered, five would have been incorrectly diagnosed as nonepileptic (5/100, 5%) compared to patients with routine EEG and MRI (25/100, 25%, p = .0001). In patients with all four examinations, advanced workup provided an overall additional yield of 50% compared to routine workup. SIGNIFICANCE: Our results demonstrate the remarkable added value of the advanced workup launched already in the ED for the diagnosis of NOE versus nonepileptic causes of seizure mimickers. Our findings suggest the benefit of first-seizure tracks or even units with overnight EEG, similar to stroke units, activated upon admission in the ED.
Subject(s)
Epilepsy , Seizures , Adult , Humans , Cohort Studies , Seizures/diagnostic imaging , Epilepsy/diagnostic imaging , Brain/diagnostic imaging , Electroencephalography , Magnetic Resonance ImagingABSTRACT
Ecstatic epilepsy is a rare form of focal epilepsy, so named because the seizures' first symptoms consist of an ecstatic/mystical experience, including feelings of increased self-awareness, mental clarity, and "unity with everything that exists," accompanied by a sense of bliss and physical well-being. In this perspective article, we first describe the phenomenology of ecstatic seizures, address their historical context, and describe the primary brain structure involved in the genesis of these peculiar epileptic seizures, the anterior insula. In the second part of the article, we move onto the possible neurocognitive underpinnings of ecstatic seizures. We first remind the reader of the insula's role in interoceptive processing and consciously experienced feelings, contextualized by the theory of predictive coding. This leads us to hypothesize that temporary disruptions to activity in the anterior insula could interrupt the generation of interoceptive prediction errors, and cause one to experience the absence of uncertainty, and thereby, a sense of bliss. The absence of interoceptive prediction errors would in fact mimic perfect prediction of the body's physiological state. This sudden clarity of bodily perception could explain the ecstatic quality of the experience, as the interoceptive system forms the basis for unified conscious experience. Our alternative hypothesis is that the anterior insula plays an overarching role in the processing of surprise and that the dysfunction caused by the epileptic discharge could interrupt any surprise exceeding expectations, resulting in a sense of complete control and oneness with the environment.
Subject(s)
Epilepsies, Partial , Epilepsy , Humans , Epilepsy/diagnostic imaging , Emotions/physiology , Seizures , Cerebral Cortex/diagnostic imagingABSTRACT
OBJECTIVE: Germline loss-of-function mutations in DEPDC5, and in its binding partners (NPRL2/3) of the mammalian target of rapamycin (mTOR) repressor GATOR1 complex, cause focal epilepsies and increase the risk of sudden unexpected death in epilepsy (SUDEP). Here, we asked whether DEPDC5 haploinsufficiency predisposes to primary cardiac defects that could contribute to SUDEP and therefore impact the clinical management of patients at high risk of SUDEP. METHODS: Clinical cardiac investigations were performed in 16 patients with pathogenic variants in DEPDC5, NPRL2, or NPRL3. Two novel Depdc5 mouse strains, a human HA-tagged Depdc5 strain and a Depdc5 heterozygous knockout with a neuron-specific deletion of the second allele (Depdc5c/- ), were generated to investigate the role of Depdc5 in SUDEP and cardiac activity during seizures. RESULTS: Holter, echocardiographic, and electrocardiographic (ECG) examinations provided no evidence for altered clinical cardiac function in the patient cohort, of whom 3 DEPDC5 patients succumbed to SUDEP and 6 had a family history of SUDEP. There was no cardiac injury at autopsy in a postmortem DEPDC5 SUDEP case. The HA-tagged Depdc5 mouse revealed expression of Depdc5 in the brain, heart, and lungs. Simultaneous electroencephalographic-ECG records on Depdc5c/- mice showed that spontaneous epileptic seizures resulting in a SUDEP-like event are not preceded by cardiac arrhythmia. INTERPRETATION: Mouse and human data show neither structural nor functional cardiac damage that might underlie a primary contribution to SUDEP in the spectrum of DEPDC5-related epilepsies. ANN NEUROL 2022;91:101-116.
Subject(s)
Epilepsies, Partial/complications , GTPase-Activating Proteins/genetics , Heart , Sudden Unexpected Death in Epilepsy/etiology , Adolescent , Adult , Animals , Electrocardiography , Electroencephalography , Epilepsies, Partial/genetics , Female , Humans , Male , Mice , Middle Aged , Mutation , Tumor Suppressor Proteins/genetics , Young AdultABSTRACT
For the first time, an ecstatic aura has been evoked through the electrical stimulation of the dorsal anterior insula during presurgical invasive intracerebral monitoring in a patient who did not suffer from an ecstatic form of epilepsy. This case provides more evidence that the anterior insula is the major generator of such a mystical-type experience even in individuals with no underlying brain network changes related to a preexisting ecstatic epilepsy. ANN NEUROL 2022;91:289-292.
Subject(s)
Cerebral Cortex/physiology , Electric Stimulation , Euphoria/physiology , Cerebral Cortex/diagnostic imaging , Drug Resistant Epilepsy/diagnostic imaging , Drug Resistant Epilepsy/surgery , Electroencephalography , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Mysticism/psychology , Tomography, X-Ray Computed , Treatment OutcomeABSTRACT
Ecstatic epilepsy is a rare form of focal epilepsy in which the aura (beginning of the seizures) consists of a blissful state of mental clarity/feeling of certainty. Such a state has also been described as a "religious" or mystical experience. While this form of epilepsy has long been recognized as a temporal lobe epilepsy, we have accumulated evidence converging toward the location of the symptomatogenic zone in the dorsal anterior insula during the 10 last years. The neurocognitive hypothesis for the genesis of a mental clarity is the suppression of the interoceptive prediction errors and of the unexpected surprise associated with any incoming internal or external signal, usually processed by the dorsal anterior insula. This mimics a perfect prediction of the world and induces a feeling of certainty. The ecstatic epilepsy is thus an amazing model for the role of anterior insula in uncertainty and surprise.
ABSTRACT
Variants in KCNT1, encoding a sodium-gated potassium channel (subfamily T member 1), have been associated with a spectrum of epilepsies and neurodevelopmental disorders. These range from familial autosomal dominant or sporadic sleep-related hypermotor epilepsy to epilepsy of infancy with migrating focal seizures (EIMFS) and include developmental and epileptic encephalopathies. This study aims to provide a comprehensive overview of the phenotypic and genotypic spectrum of KCNT1 mutation-related epileptic disorders in 248 individuals, including 66 previously unpublished and 182 published cases, the largest cohort reported so far. Four phenotypic groups emerged from our analysis: (i) EIMFS (152 individuals, 33 previously unpublished); (ii) developmental and epileptic encephalopathies other than EIMFS (non-EIMFS developmental and epileptic encephalopathies) (37 individuals, 17 unpublished); (iii) autosomal dominant or sporadic sleep-related hypermotor epilepsy (53 patients, 14 unpublished); and (iv) other phenotypes (six individuals, two unpublished). In our cohort of 66 new cases, the most common phenotypic features were: (i) in EIMFS, heterogeneity of seizure types, including epileptic spasms, epilepsy improvement over time, no epilepsy-related deaths; (ii) in non-EIMFS developmental and epileptic encephalopathies, possible onset with West syndrome, occurrence of atypical absences, possible evolution to developmental and epileptic encephalopathies with sleep-related hypermotor epilepsy features; one case of sudden unexplained death in epilepsy; (iii) in autosomal dominant or sporadic sleep-related hypermotor epilepsy, we observed a high prevalence of drug-resistance, although seizure frequency improved with age in some individuals, appearance of cognitive regression after seizure onset in all patients, no reported severe psychiatric disorders, although behavioural/psychiatric comorbidities were reported in â¼50% of the patients, sudden unexplained death in epilepsy in one individual; and (iv) other phenotypes in individuals with mutation of KCNT1 included temporal lobe epilepsy, and epilepsy with tonic-clonic seizures and cognitive regression. Genotypic analysis of the whole cohort of 248 individuals showed only missense mutations and one inframe deletion in KCNT1. Although the KCNT1 mutations in affected individuals were seen to be distributed among the different domains of the KCNT1 protein, genotype-phenotype considerations showed many of the autosomal dominant or sporadic sleep-related hypermotor epilepsy-associated mutations to be clustered around the RCK2 domain in the C terminus, distal to the NADP domain. Mutations associated with EIMFS/non-EIMFS developmental and epileptic encephalopathies did not show a particular pattern of distribution in the KCNT1 protein. Recurrent KCNT1 mutations were seen to be associated with both severe and less severe phenotypes. Our study further defines and broadens the phenotypic and genotypic spectrums of KCNT1-related epileptic conditions and emphasizes the increasingly important role of this gene in the pathogenesis of early onset developmental and epileptic encephalopathies as well as of focal epilepsies, namely autosomal dominant or sporadic sleep-related hypermotor epilepsy.
Subject(s)
Epilepsy/genetics , Nerve Tissue Proteins/genetics , Potassium Channels, Sodium-Activated/genetics , Adolescent , Child , Child, Preschool , Cohort Studies , Female , Genotype , Humans , Infant , Male , Mutation , Phenotype , Young AdultABSTRACT
Until now, there are few information on vitamin B2 concentration variability in milk. In this study, a novel analytical method to quantify total vitamin B2 in milk was developed and applied on 676 samples. In parallel, spectral analysis (colorimetry and near infrared spectroscopy) were performed to develop prediction models of vitamin B2 concentration in milk. The analytical method includes an acid and enzymatic extraction followed by vitamin B2 quantification by Ultra High Performance Liquid Chromatography coupled with fluorimetry. Samples analysis showed a wide range of concentration from 0.78 to 4.58 mg/L with a mean of 2.09 ± 0.48 mg/L. Two prediction models based on colorimetric analysis allow estimation of vitamin B2 concentration in milk. Thus, this work shows an analytical method and, for the first time, a prediction method to enable enhancement of researches on vitamin B2 content of milk and its variation factors.
Subject(s)
Chromatography, High Pressure Liquid/methods , Milk/chemistry , Riboflavin/analysis , Spectroscopy, Near-Infrared/methods , Animals , Cattle , FemaleABSTRACT
AIMS OF THE STUDY: Hydroxychloroquine and lopinavir/ritonavir have been used as experimental therapies to treat COVID-19 during the first wave of the pandemic. Randomised controlled trials have recently shown that there are no meaningful benefits of these two therapies in hospitalised patients. Uncertainty remains regarding the potential harmful impact of these therapies as very early treatments and their burden to the health care system. The present study investigated the length of hospital stay (LOS), mortality, and costs of hydroxychloroquine, lopinavir/ritonavir or their combination in comparison with standard of care among patients hospitalised for coronavirus disease 2019 (COVID-19). METHODS: This retrospective observational cohort study took place in the Geneva University Hospitals, Geneva, Switzerland (n = 840) between 26 February and 31 May 2020. Demographics, treatment regimens, comorbidities, the modified National Early Warning Score (mNEWS) on admission, and contraindications to COVID-19 treatment options were assessed. Outcomes included LOS, in-hospital mortality, and drug and LOS costs. RESULTS: After successful propensity score matching, patients treated with (1) hydroxychloroquine, (2) lopinavir/ritonavir or (3) their combination had on average 3.75 additional hospitalisation days (95% confidence interval [CI] 1.37–6.12, p = 0.002), 1.23 additional hospitalisation days (95% CI −1.24 – 3.51, p = 0.319), and 4.19 additional hospitalisation days (95% CI 1.52–5.31, p <0.001), respectively, compared with patients treated with the standard of care. Neither experimental therapy was significantly associated with mortality. These additional hospital days amounted to 1010.77 additional days for hydroxychloroquine and hydroxychloroquine combined with lopinavir/ritonavir, resulting in an additional cost of US$ 2,492,214 (95%CI US$ 916,839–3,450,619). CONCLUSIONS: Prescribing experimental therapies for COVID-19 was not associated with a reduced LOS and might have increased the pressure put on healthcare systems.
Subject(s)
Antiviral Agents/therapeutic use , COVID-19 Drug Treatment , COVID-19/epidemiology , Hydroxychloroquine/therapeutic use , Lopinavir/therapeutic use , Ritonavir/therapeutic use , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Antiviral Agents/administration & dosage , Antiviral Agents/adverse effects , COVID-19/mortality , Child , Child, Preschool , Comorbidity , Drug Combinations , Drug Therapy, Combination , Health Expenditures , Hospital Mortality/trends , Humans , Hydroxychloroquine/administration & dosage , Hydroxychloroquine/adverse effects , Infant , Length of Stay/statistics & numerical data , Lopinavir/administration & dosage , Lopinavir/adverse effects , Middle Aged , Pandemics , Retrospective Studies , Ritonavir/administration & dosage , Ritonavir/adverse effects , SARS-CoV-2 , Severity of Illness Index , Sex Factors , Socioeconomic Factors , Therapies, Investigational/methods , Young AdultABSTRACT
PURPOSE: Epilepsy patients consider driving issues to be one of their most serious concerns. Ideally, decisions regarding fitness to drive should be based upon thorough evaluations by specialists in epilepsy care. In 2009, an EU directive was published aiming to harmonize evaluation practices within European countries, but, despite these recommendations, whether all epileptologists use the same criteria is unclear. We therefore conducted this study to investigate routine practices on how epileptologists at European epilepsy centers evaluate fitness to drive. METHODS: A questionnaire was sent to 63 contact persons identified through the European Epi-Care and the E-pilepsy network. The questionnaire addressed how fitness-to-drive evaluations were conducted, the involvement of different professionals, the use and interpretation of EEG, and opinions on existing regulations and guidelines. RESULTS: The questionnaire was completed by 35 participants (56 % response rate). Results showed considerable variation regarding test routines and the emphasis placed on the occurrence and extent of epileptiform discharges revealed by EEG. 82 % of the responders agreed that there was a need for more research on how to better evaluate fitness-to-drive in people with epilepsy, and 89 % agreed that regulations on fitness to drive evaluations should be internationally coordinated. CONCLUSION: Our survey showed considerable variations among European epileptologists regarding use of EEG and how findings of EEG pathology should be assessed in fitness-to-drive evaluations. There is a clear need for more research on this issue and international guidelines on how such evaluations should be carried out would be of value.
Subject(s)
Attitude of Health Personnel , Automobile Driving/legislation & jurisprudence , Automobile Driving/statistics & numerical data , Disability Evaluation , Epilepsy/epidemiology , Neurologists/statistics & numerical data , Practice Patterns, Physicians'/statistics & numerical data , Adult , Electroencephalography , Europe/epidemiology , Female , Humans , Male , Middle Aged , Surveys and QuestionnairesABSTRACT
Nicotinic acetylcholine receptors (nAChRs) are widely distributed in the human brain and play an important role in the neuromodulation of brain networks implicated in attentional processes. Previous work in humans showed that heteromeric α4ß2 nAChRs are abundant in the cingulo-insular network underlying attentional control. It has been proposed that cholinergic neuromodulation by α4ß2 nAChRs is involved in attentional control during demanding tasks, when additional resources are needed to minimize interference from task-irrelevant stimuli and focus on task-relevant stimuli. Here we investigate the link between the availability of α4ß2 nAChRs in the cingulo-insular network and behavioral measures of interference control using two versions of the Stroop paradigm, a task known to recruit cingulo-insular areas. We used a previously published PET dataset acquired in 24 non-smoking male subjects in the context of a larger study which investigated the brain distribution of nAChRs in two clinical groups using 2-[(18)F]F-A-85380 PET. We found that higher availability of α4ß2 nAChRs in the dorsal anterior cingulate cortex (ACC) predicted better interference control independently of group and age. In line with animal models, our results support the view that the availability of α4ß2 nAChRs in the dorsal ACC is linked with more efficient attentional control.
Subject(s)
Attention/physiology , Gyrus Cinguli/metabolism , Receptors, Nicotinic/metabolism , Adolescent , Adult , Humans , Male , Middle Aged , Positron-Emission Tomography , Stroop Test , Young AdultABSTRACT
OBJECTIVE: Autosomal dominant sleep-related hypermotor epilepsy (ADSHE) is characterized by hypermotor seizures and may be caused by gain-of-function mutations affecting the nicotinic acetylcholine receptor (nAChR). Benefit from nicotine consumption has been reported in adult patients with this disorder. For the first time, the effect of transdermal nicotine is evaluated in children. METHODS: Transdermal nicotine was applied to three boys, two aged 10â¯years (7â¯mg/24â¯h) and one six years (3.5â¯mg/24â¯h). Autosomal dominant sleep-related hypermotor epilepsy was caused by the p.S280F-CHRNA4 (cholinergic receptor, nicotinic, alpha polypeptide 4) mutation. The children suffered from frequent, persistent nocturnal seizures and had developed educational and psychosocial problems. Seizure frequency and cognitive and behavioral parameters were assessed before and after treatment. RESULTS: A striking seizure reduction was reported soon after treatment onset. Hypermotor seizures disappeared; only sporadic arousals, sometimes with minor motor elements, were observed. Psychometric testing documented improvement in cognitive domains such as visuospatial ability, processing speed, memory, and some areas of executive functions. SIGNIFICANCE: Nicotine appears to be a mechanistic treatment for this specific disorder, probably because of desensitization of the mutated receptors. It may control seizures resistant to conventional drugs for epilepsy and impact socioeducational function in children. This mode of precision therapy should receive more attention and should be available to more patients with uncontrolled CHRNA4-related ADSHE across the age span.
Subject(s)
Epilepsy, Reflex/drug therapy , Epilepsy, Reflex/genetics , Nicotine/administration & dosage , Receptors, Nicotinic/genetics , Sleep/genetics , Tobacco Use Cessation Devices , Adolescent , Child , Epilepsy, Reflex/diagnosis , Humans , Male , Mutation/genetics , Sleep/drug effects , Treatment OutcomeABSTRACT
PURPOSE: The parcellation of the thalamus into different nuclei involved in different corticothalamocortical loops reflects its functional diversity. The connections between the mediodorsal nucleus and the prefrontal cortex play a major role in cognition, particularly in the rapid processing of behaviorally relevant information. The thalamus is the brain region with the highest density in α4ß2 nicotinic acetylcholine receptors, the main human nicotinic acetylcholine receptor subtype. The aim of this study was to investigate the possible role of the nicotinic cholinergic system in the thalamo-cortical loops measuring receptor density in different subregions of the thalamus, based on their cortical connectivity. PROCEDURES: We studied α4ß2 nicotinic acetylcholine receptors using positron emission tomography and [18F]Fluoro-A-85380, a radiotracer specific for this receptor subtype, in 36 non-smoking male subjects, including 12 healthy controls and 24 patients with epilepsy. [18F]Fluoro-A-85380 ratio index of binding potential was compared by a repeated measures general linear model, including the thalamic subregions and the brain hemisphere as within-subject factor and clinical groups as between-subject factor. RESULTS: The "prefrontal" thalamus, the subregion including the mediodorsal nucleus, had a significantly higher nicotinic acetylcholine receptor density than all other thalamic subregions. These findings were confirmed when analyzing solely the 12 healthy controls. CONCLUSIONS: This particular neurochemical organization of the thalamus supports a major role of the cholinergic system in the loops between the thalamus and the prefrontal cortex. The highest nicotinic acetylcholine receptor density in the « higher-order thalamus ¼ could partly explain the beneficial effect of acute nicotine on attentional and executive functions and possibly the pathophysiology of some neuropsychiatric disorders.
Subject(s)
Epilepsy/diagnostic imaging , Prefrontal Cortex/diagnostic imaging , Receptors, Nicotinic/metabolism , Thalamus/diagnostic imaging , Adult , Brain Mapping , Cognition , Humans , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Male , Middle Aged , Positron-Emission Tomography , Receptors, Nicotinic/chemistryABSTRACT
The dorsal anterior cingulate cortex (dACC) and the anterior insula (AI) constitute the salience network and form as well the major cortical components of the central autonomic nervous system. These two cortical regions have the highest density in α4ß2 nicotinic acetylcholine receptors (nAChRs) within the whole cortex.The aim of the study was to test the association between nAChRs density/availability in the salience network and the heart rate variability in humans. We selected subjects from a previous positron emission tomography (PET) imaging study in epilepsy with 18F-FA-85380, a specific marker for α4ß2 nAChRs, including 10 healthy controls, 10 patients with nonlesional focal epilepsy and 8 patients with idiopathic generalized epilepsy. Participants underwent a 10 min-resting electrocardiogram as they were lying still in a semi-supine position while watching an emotionally neutral video. We tested the association between parasympathetic tone and the regional brain nAChR availability, as measured by 18F-F-A-85380 binding potential (BP), using linear regression. We observed an association between higher nAChRs availability in the bilateral dACC and the right dorsal AI/frontal operculum and a lower parasympathetic tone, without significant effect of the clinical group on this relation. Our study is the first one to show a neurochemical correlate to the parasympathetic role of the anterior cingulate cortex and the AI. The nicotinic system, which plays a major role in the peripheral autonomic nervous system intervening both in the parasympathetic and sympathetic chains, seems also to play a role in the central autonomic nervous system.
Subject(s)
Cerebral Cortex/metabolism , Gyrus Cinguli/metabolism , Heart Rate/physiology , Nerve Net/metabolism , Parasympathetic Nervous System/metabolism , Receptors, Nicotinic/metabolism , Adult , Cerebral Cortex/diagnostic imaging , Gyrus Cinguli/diagnostic imaging , Humans , Male , Middle Aged , Nerve Net/diagnostic imaging , Parasympathetic Nervous System/diagnostic imagingABSTRACT
PURPOSE: FDG PET is an established tool in presurgical epilepsy evaluation, but it is most often used selectively in patients with discordant MRI and EEG results. Interpretation is complicated by the presence of remote or multiple areas of hypometabolism, which leads to doubt as to the true location of the seizure onset zone (SOZ) and might have implications for predicting the surgical outcome. In the current study, we determined the sensitivity and specificity of PET localization prospectively in a consecutive unselected cohort of patients with focal epilepsy undergoing in-depth presurgical evaluation. METHODS: A total of 130 patients who underwent PET imaging between 2006 and 2015 matched our inclusion criteria, and of these, 86 were operated on (72% with a favourable surgical outcome, Engel class I). Areas of focal hypometabolism were identified using statistical parametric mapping and concordance with MRI, EEG and intracranial EEG was evaluated. In the surgically treated patients, postsurgical outcome was used as the gold standard for correctness of localization (minimum follow-up 12 months). RESULTS: PET sensitivity and specificity were both 95% in 86 patients with temporal lobe epilepsy (TLE) and 80% and 95%, respectively, in 44 patients with extratemporal epilepsy (ETLE). Significant extratemporal hypometabolism was observed in 17 TLE patients (20%). Temporal hypometabolism was observed in eight ETLE patients (18%). Among the 86 surgically treated patients, 26 (30%) had hypometabolism extending beyond the SOZ. The presence of unilobar hypometabolism, included in the resection, was predictive of complete seizure control (p = 0.007), with an odds ratio of 5.4. CONCLUSION: Additional hypometabolic areas were found in one of five of this group of nonselected patients with focal epilepsy, including patients with "simple" lesional epilepsy, and this finding should prompt further in-depth evaluation of the correlation between EEG findings, semiology and PET. Hypometabolism confined to the epileptogenic zone as defined by EEG and MRI is associated with a favourable postoperative outcome in both TLE and ETLE patients.
Subject(s)
Epilepsies, Partial/metabolism , Epilepsies, Partial/surgery , Predictive Value of Tests , Adult , Child , Child, Preschool , Cohort Studies , Electroencephalography , Epilepsies, Partial/diagnostic imaging , Female , Humans , Infant , Infant, Newborn , Magnetic Resonance Imaging , Male , Middle Aged , Positron-Emission Tomography , Prospective Studies , Sensitivity and Specificity , Young AdultABSTRACT
First seizures are a diagnostic challenge in the emergency room. The differential diagnosis includes epileptic seizures, syncopes and psychogenic non-epileptic seizures. Importantly, amongst first epileptic seizures, acute symptomatic seizures should be distinguished from unprovoked seizures that define epilepsy. The early accurate diagnosis of first seizures is an important issue because of the therapeutic and prognostic implications at stake. In addition to gathering a detailed history, some ancillary tests may be warranted early on in patients' management. In this article, we present some definitions and describe clinical and work up features that might help accurately classify and appropriately manage such cases in the emergency room.
Les crises épileptiques inaugurales arrivant aux urgences représentent un enjeu diagnostique de taille. Le diagnostic différentiel d'une première crise épileptique comprend notamment les syncopes convulsivantes et les crises psychogènes non épileptiques. En cas de première crise épileptique, savoir identifier une crise provoquée d'une crise d'épilepsie-maladie est un autre défi. L'enjeu diagnostique initial est donc important car les implications thérapeutiques et pronostiques sont différentes selon l'étiologie retenue. Outre l'anamnèse très détaillée, un certain nombre d'examens spécialisés doivent être réalisés de manière précoce. Nous présentons dans cet article des éléments diagnostiques cliniques et paracliniques à mettre en Åuvre dans la prise en charge précoce des patients.