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The electroencephalogram (EEG) is a non-invasive and cost-effective method to monitor spontaneous neuronal activity over time. Pathologies in EEG recordings indicate with high sensitivity but low specificity abnormal functional brain states.The main psychiatric indications for EEG recordings include atypical clinical symptoms of a neuropsychiatric syndrome or atypical reactions to medication as well as a baseline diagnostic before starting treatment with specific drugs or stimulation modalities. In recent research the EEG continues to be a valuable tool not only in diagnostics but also for the prediction of treatment success.The following paper focuses on basic electrophysiological understanding of EEG recordings, the diagnostic value of EEG recordings in different clinical entities, and new research attempts in diagnostic and treatment prediction. [ABSTRACT FROM AUTHOR]

Summary Objectives Assessment of current practice and the need for tele-transmission and remote interpretation of EEG in France. Transmission of EEG to a distant center could be a promising solution to the problem of decreasing availability of neurophysiologists for EEG interpretation, in order to provide equity within health care services in France. This practice should logically follow the legal framework of telemedicine and the recommendations that were recently edited by the Société de neurophysiologie clinique de langue française (SNCLF) and the Ligue française contre l’épilepsie (LCFE). Methods A national survey was designed and performed under the auspices of the SNCLF. Results This survey reveals that there is an important gap between the official recommendations and the “reality on the ground”. These local organizations were mainly established through the impulse of individual initiatives, rarely driven by health regulatory authorities and sometimes far from legal frameworks. For the majority, they result from a need to improve medical care, especially in pediatrics and neonatology, and to ensure continuity of care. When present, tele-transmission of EEG is often only partially satisfactory, since many technical procedures have to be improved. Conversely, the lack of tele-transmission of EEG would penalize medical care for some patients. Conclusions The survey shows both the wealth of local initiatives and the fragility of most existing networks, emphasizing the need for better cooperation between regulatory authorities and health care professionals to establish or improve the transmission of EEG in France. [ABSTRACT FROM AUTHOR]

This paper addresses drivers' psycho-physiological condition under the influence of various freeway section types and elapsed driving times. The authors analyzed the electroencephalogram (EEG) signals ( α, β, and θ) of 51 drivers on a freeway in Korea. The findings show that the driver's workload increases in tunnels and on left-curved sections, and that his or her concentration and response ability decrease after 60 min of elapsed driving time. The β/α ratios of EEG signals were found to be most effective in detecting differences in psycho-physiological responses. The results can help to promote safety on freeways by encouraging drivers to take rests every hour. [ABSTRACT FROM AUTHOR]

Résumé Introduction Les maladies chroniques représentent de façon générale un facteur de risque significatif de morbidité psychiatrique, mais l’épilepsie elle-même, comme les autres affections neurologiques, est un facteur de risque supplémentaire, en particulier en ce qui concerne les troubles psychotiques. Leur prévalence est estimée entre 2 et 7 % chez les épileptiques. Cas Nous rapportons le cas d’un patient de 58 ans, épileptique méconnu, qui a présenté trois épisodes délirants aigus à plusieurs années d’intervalle, sans manifestations psychiatriques inter-critiques. L’EEG réalisé de façon systématique a permis de mettre en évidence un foyer épileptique de localisation fronto-temporale. Discussion L’origine épileptique d’un tableau psychotique aigu doit toujours être recherchée par la réalisation systématique d’un EEG. La localisation temporale est retrouvée de façon plus fréquente dans ce type de tableau. La comorbidité psychose et épilepsie soulève des difficultés diagnostiques et thérapeutiques. Conclusion Une bonne collaboration entre les psychiatres et les neurologues est plus que souhaitable, afin d’adapter au mieux les traitements. Introduction It is well known that there is a significant relationship between chronic diseases and mental health. People who suffer from a chronic disease especially epilepsy are more likely to also suffer from neurobehavioral disorders; the prevalence of psychosis is estimated between 2 and 7% in this particular case. The case We report the case of a 58-year-old patient, non-diagnosed epileptic until now, who presented 3 acute delusional episodes during his life, without any intercritical psychiatric symptoms. The EEG performed systematically helped highlighting an epileptical activity mostly focused on the frontotemporal areas. Discussion The epileptic origin of an acute psychotic episode should always be sought by a systematic EEG. The temporal localization is the most frequent one in such cases. Psychosis and epilepsy comorbidity raises diagnostic and therapeutic difficulties. Conclusion Good collaboration between psychiatrists and neurologists is highly desirable in order to better adapt the treatment. [ABSTRACT FROM AUTHOR]

Summary Electroencephalography allows the functional analysis of electrical brain cortical activity and is the gold standard for analyzing electrophysiological processes involved in epilepsy but also in several other dysfunctions of the central nervous system. Morphological imaging yields complementary data, yet it cannot replace the essential functional analysis tool that is EEG. Furthermore, EEG has the great advantage of being non-invasive, easy to perform and allows repeat testing when follow-up is necessary, even at the patient's bedside. Faced with advances in knowledge, techniques and indications, the Société de neurophysiologie clinique de langue française (SNCLF) and the Ligue française contre l’épilepsie (LFCE) found it necessary to provide an update on EEG recommendations. This article will review the methodology applied to this work, refine the various topics detailed in the following chapters. It will go over the summary of recommendations for each of these chapters and highlight proposals for writing an EEG report. Some questions could not be answered by review of the literature; in such cases, in addition to the guidelines the working and reading groups provided their expert opinion. [ABSTRACT FROM AUTHOR]

Summary Continuous EEG monitoring in the ICU is different from planned EEG due to the rather urgent nature of the indications, explaining the fact that recording is started in certain cases by the clinical team in charge of the patient's care. Close collaboration between neurophysiology teams and intensive care teams is essential. Continuous EEG monitoring can be facilitated by quantified analysis systems. This kind of analysis is based on certain signal characteristics, such as amplitude or frequency content, but raw EEG data should always be interpreted if possible, since artefacts can sometimes impair quantified EEG analysis. It is preferable to work within a tele-EEG network, so that the neurophysiologist has the possibility to give an interpretation on call. Continuous EEG monitoring is thus useful in the diagnosis of non-convulsive epileptic seizures or purely electrical discharges and in the monitoring of status epilepticus when consciousness disorders persist after initial treatment. A number of other indications are currently under evaluation. [ABSTRACT FROM AUTHOR]

Summary In France, for the determination and diagnostic validation of brain death the law requires either two EEG recordings separated by a 4-hour observation period, both showing electrocerebral inactivity; or cerebral angiography examination. Since EEG is available in most hospitals and clinics, it is often used in this indication, at the patient's bedside, especially in the context of organ donation. However, very precise methodology must be followed. The last French guidelines date back to 1989, before the development of digital EEG recording. We present the new guidelines from the Société de Neurophysiologie Clinique de Langue Française. Electrocerebral inactivity may be confirmed when a 30-minute good quality EEG recording shows complete electrocerebral silence, defined as no cerebral activity greater than 2 uV, having first ruled out the possible influence of sedative drugs, metabolic disorders or hypothermia. In the presence of sedative drugs, CT brain angiography will be the gold standard test for this diagnosis. In the newborn, the utmost caution is indicated since electrocerebral inactivity can be observed in the absence of cerebral death. In the infant, the criterion for the observation period to be respected between both EEG recordings needs to be more clearly refined. [ABSTRACT FROM AUTHOR]

Summary EEG recordings can be sent for remote interpretation. This article aims to define the tele-EEG procedures and technical guidelines. Tele-EEG is a complete medical act that needs to be carried out with the same quality requirements as a local one in terms of indications, formulation of the medical request and medical interpretation. It adheres to the same quality requirements for its human resources and materials. It must be part of a medical organization (technical and medical network) and follow all rules and guidelines of good medical practices. The financial model of this organization must include costs related to performing the EEG recording, operating and maintenance of the tele-EEG network and medical fees of the physician interpreting the EEG recording. Implementing this organization must be detailed in a convention between all parties involved: physicians, management of the healthcare structure, and the company providing the tele-EEG service. This convention will set rules for network operation and finance, and also the continuous training of all staff members. The tele-EEG system must respect all rules for safety and confidentiality, and ensure the traceability and storing of all requests and reports. Under these conditions, tele-EEG can optimize the use of human resources and competencies in its zone of utilization and enhance the organization of care management. [ABSTRACT FROM AUTHOR]

Résumé L’électroencéphalogramme (EEG) permet une analyse fonctionnelle du signal électrique cérébral et constitue l’examen de référence pour analyser les processus électrophysiologiques sous-tendant l’épilepsie mais également de nombreux autres dysfonctionnements du système nerveux central. Les examens d’imagerie morphologique apportent des renseignements complémentaires de l’EEG mais ne peuvent se substituer à cet outil d’analyse fonctionnelle. L’EEG a de plus l’avantage d’être non invasif, facile à réaliser et à contrôler quand un suivi est nécessaire, y compris au lit du patient. Face à l’évolution des connaissances, des techniques et des indications, une actualisation des recommandations sur l’EEG a été jugée nécessaire par la Société de Neurophysiologie Clinique de Langue Française (SNCLF) et la Ligue Française contre l’Épilepsie (LFCE). Cet article aborde la méthodologie adoptée pour ce travail de recommandations, précise les différentes thématiques détaillées dans les chapitres suivants et reprend les fiches synthétiques de recommandation de chacun de ces chapitres ainsi que des propositions de rédaction du compte-rendu d’EEG. La revue de la littérature n’a pas permis d’apporter une réponse à certaines questions pour lesquelles un avis d’experts a cependant été exprimé par le groupe de travail et de lecture en complément des recommandations. Summary Electroencephalography allows the functional analysis of electrical brain cortical activity and is the gold standard for analyzing electrophysiological processes involved in epilepsy but also in several other dysfunctions of the central nervous system. Morphological imaging yields complementary data, yet it cannot replace the essential functional analysis tool that is EEG. Furthermore, EEG has the great advantage of being non-invasive, easy to perform and allows control tests when follow-up is necessary, even at the patient's bedside. Faced with the advances in knowledge, techniques and indications, the Société de Neurophysiologie Clinique de Langue Française (SNCLF) and the Ligue Française Contre l’Épilepsie (LFCE) found it necessary to provide an update on EEG recommendations. This article will review the methodology applied to this work, refine the various topics detailed in the following chapters. It will go over the summary of recommendations for each of these chapters and underline proposals for writing an EEG report. Some questions could not be answered by the review of the literature; in those cases, an expert advice was given by the working and reading groups in addition to the guidelines. [ABSTRACT FROM AUTHOR]

Summary: The important EEG changes that occur throughout childhood are a major challenge for the neurophysiologist. These reflect brain maturation, which is especially fast during the first year of life. This article describes normal EEG features and variants, characteristic patterns of development, as well as some patterns that are unusual for age, from the neonatal period to adolescence. We also describe how to adapt techniques and prepare patients in order to get interpretable records of appropriate duration, in neonates, infants, and young children. [Copyright &y& Elsevier]

Summary: Objective: To determine the prognostic value of early electroencephalograms (EEG) in full-term neonates suffering from hypoxic ischemic encephalopathy (HIE) exposed to whole-body hypothermia (cooled group), compared to neonates treated conventionally (control group). Methods: The study included all term neonates born at Grenoble Hospital between 2000 and 2006 with symptoms of HIE. The first two EEGs were reviewed retrospectively and classified according to current electrophysiological criteria. In the cooled group, EEGs were recorded with a mean body temperature of 33°C. Neurological outcome was correlated with EEG pattern. Results: An EEG inactive or paroxysmal pattern was associated with death in 60% of the controls, while all survivors had neurological sequels. In the cooled group, this EEG pattern was only predictive of death in 40% while survivors had normal examination at 1year of age. Mild abnormalities on the first EEG correlated with a good prognosis in both groups. The second EEG had a high predictive value, particularly in the cooled group. Persistence of inactivity at 3days after birth was always associated with death. Conclusions: After HIE, the first two EEGs are good prognostic indicators, also in the cooled group. Strong discontinuity in the EEG observed on the first hours after hypothermia induction can be associated with a good outcome. Significance: Early Stage 4 EEGs recorded during the hypothermia may not always indicate a poor prognosis in HIE. [Copyright &y& Elsevier]

Summary: In the late nineteenth century, French logician Edmond Goblot first hypothesized that dreaming occurred at the moment of awakening only. Revisiting – more or less directly – Goblot''s hypothesis, several contemporary authors have since renewed this unusual claim that oniric experience does not occur during sleep. So did some influential analytical philosophers (Wittgenstein, Malcolm, Dennett), with their typical formalism, and famous dream researcher Calvin Hall, who tried to provide experimental evidence for the Goblot''s hypothesis. More recently, French neurobiologist Jean-Pol Tassin claimed, on the basis of controversial neurobiological and cognitive principles, that only awakening gives rise to a dream, by instantaneous shaping of information issuing of neural networks activated during preceding sleep. Actually, numerous and robust experimental data in sleep psychophysiology clearly rule out Goblot''s hypothesis and its modern avatars. Thus, results of studies using nocturnal awakenings (with or without preceding hypnic stimulation), as well as observations of onirical behaviours (like rapid eye movement sleep behavior disorders, or voluntary movements of lucid dreamers) demonstrate that dreaming definitely occurs during sleep. Actually, cortical evoked potentials can be observed during sleep, which likely reflect controlled cognitive processes. Dreaming is a hypnic state of consciousness, and seems to represent a sleep thought which, although uneasily accessible, is nevertheless open to psychological investigation. [Copyright &y& Elsevier]

Abstract: We report a case of a falsely elevated-bispectral index (BIS™) during a general anaesthesia combining remifentanil TCI, desflurane and nitrous oxide for an isolated-limb chemotherapy. During surgery, BIS™ increased and stabilized around 70, with neither residual neuromuscular blockade nor clinical sign of awareness. These high BIS™ values were attributed to high-electromyographic activity and electric artefacts, such as extracorporeal-circulation machine and tourniquet. At the end of the surgery, the BIS™ returned to expected values around 50. The patient did not complain of intraoperative recall. This case reminds us that the BIS™ has some limits as being sensitive to EMG or environment artefacts that should be eliminated before deepening anesthesia. To do so, a decision algorithm is proposed that may be used for all situations of surprising high BIS™, taking into account the level of neuromuscular blockade, clinical response to orders and the presence of devices likely to induce electrical or mechanical artefacts. [Copyright &y& Elsevier]

Abstract: Sedation-analgesia occupies an essential place in the specific therapeutic arsenal of the brain-injured patients. The maintenance of the perfusion of the brain, its relaxation and its protection are the fundamental objectives whose finality is to avoid the extension of the lesions and to preserve the neuronal capital. Sedation is instituted when patients are severely agitated or present a deterioration of their state of consciousness (GCS≤8). Under cover of mechanical ventilation, sedation is the first line treatment of intracranial hypertension, a common pathway of various acute brain diseases of traumatic, vascular or other origin. The use of the combination of hypnotic and opioids is the rule. The combined action of these two classes reinforces and improves their sedative effects. Midazolam is the 2 benzodiazepine of reference. Propofol is more and more frequently added to the combination of hypnotic and opioids. The “propofol infusion syndrome” is a severe limitation to its long term administration in particular among patients presenting a severe septic or inflammatory state. Propofol will be imperatively stopped in the event of metabolic acidosis, rhabdomyolysis, acute renal insufficiency, hyperkaliemy or increase in the blood triglyceride levels. The use of thiopental is restricted to the most severe cases. Its use as a monotherapy at high doses is abandoned to the profit of a co-administration with midazolam or even with the combination of midazolam and propofol. Thiopental overdose is very frequent in the event of associated hypothermia. Etomidate does not have its place apart from induction in fast sequence. The neuro-protective effects of ketamine require to be demonstrated in man before being recommended routinely. Withdrawal of sedation can be responsible for a state of agitation which can be controlled by neuroleptics. [Copyright &y& Elsevier]

Abstract: Delayed neurological deficit occurs among 30% of patients after aneurysmal subarachnoid haemorrhage, mainly related to cerebral vasospasm. The early detection of cerebral ischemia remains problematic. Conventional cerebral monitoring (as intracranial pressure and cerebral perfusion pressure) appears to be insufficient, because cerebral ischemia may occur without elevated intracranial pressure. Global cerebral monitoring as venous jugular oxygen saturation are useful for regional monitoring. Local monitoring as oxygen tissue partial pressure (PtiO2) and microdialysis are sensible for brain ischemia detection, but may also ignore episodes occurring in non-monitored brain area. For the detection of most episodes of brain ischemia, several monitoring system should be use performing a multimodal intracerebral monitoring. Brain microdialysis and oxygen tissue partial pressure are promising monitoring system. [Copyright &y& Elsevier]

Summary: Electroencephalography (EEG) recording techniques in early premature babies are not very different from those used for full-term neonates. Here, we emphasise the most important points: asepsis precautions, full knowledge of the clinical data and drug therapies, fundamental role of a well-trained technician in supervising the EEG recording and monitoring the baby. We discuss the best electrode positions, the most informative montages, and their standardisation between neurophysiological laboratories. Artefact detection constitutes an important aspect of EEG signal analysis in preterm babies of less than 30 weeks. It is obviously necessary to discriminate between meaningful information and artefacts. The complexity of the signal in neonates makes artefact detection difficult. We present some characteristic features and describe some methods for eliminating them. We underline the positive aspect of some artefacts and their clinical use. We emphasise the crucial role of the technicians. [Copyright &y& Elsevier]

Summary: EEG recording techniques in early premature babies are not very different from those used for full-term neonates. Here, we emphasise the most important points: asepsis precautions, full knowledge of the clinical data and drug therapies, the fundamental role of a well-trained technician in supervising the EEG recording and monitoring the baby. The best electrode positions, the most informative montages and their standardisation between neurophysiological laboratories, are suggested. Artifact detection constitutes an important aspect of EEG signal analysis in preterm babies of less than 30 weeks. It is obviously necessary to discriminate between meaningful information and artefacts. The complexity of the signal in neonates makes artifact detection difficult. We present some characteristic features and describe some methods for eliminating them. We underline the positive aspect of some artifacts and their clinical use. We emphasise the crucial role of the technicians. [Copyright &y& Elsevier]

Abstract: In full-term newborns, unilateral and recurrent clonic seizures which occur during the first 48 hours of life suggest an isolated unilateral ischemic stroke. These focal seizures are isolated, occuring during a short period, or make up a status epilepticus. Electroencephalogram (EEG) is a key tool for crisis and focal cerebral process diagnosis. It also allows to assess antiepileptic drugs effectiveness. But cerebral imaging is necessary to confirm vascular origin of the cerebral impairment. Hematologic data are also needful to look for a family thromphilia. Some particular unilateral EEG abnormalities could be associated with controlateral motor sequelae or long term behavioral problems. These findings may be used for prospective studies aimed at specifying possible links between EEG abnormalities and long term outcome. [Copyright &y& Elsevier]

Abstract: Epilepsy is among the most frequent finding in many chromosome aberrations. While most chromosome aberrations can be associated with different seizure types, there are few aberrations which feature specific seizures and EEG patterns. Among the 400 different chromosomal imbalances described with seizures and EEG abnormalities, eight have a high association with epilepsy. These comprise: the monosomy 1p36, Wolf-Hirschhorn syndrome (4p-), Angelman syndrome, Miller-Dieker del 17p13.3, the inversion duplication 15 syndrome, ring 20 and ring 14 syndromes, Down’s syndrome. These chromosomal regions where aberrations have an evident association with epilepsy may be useful targets for gene hunters. On the other hand, a better characterisation of epileptic syndrome in these disorders may lead to a better and specific treatment. [Copyright &y& Elsevier]

Abstract: Objectives. – This work aimed at describing EEG abnormalities in epileptic patients living in areas endemic for cysticercosis, underlining the electroclinical correlations and discussing the interest of EEG examination in this context. Methods. – During a case-control study, 250 EEGs from patients with epilepsy were recorded with a portable system. Types of seizures were assessed clinically and from information obtained through a standardised questionnaire, and along with EEG were related to the results of cysticercosis serological tests. Results. – Among the 249 EEGs, 48% were normal, 5.2% had epileptic abnormalities, 6.8% showed an association between epileptic abnormalities and slow alterations. Slow theta and delta abnormalities were found in 21.8% of cases, and isolated deterioration of basic rhythms was observed in 17.3% of cases. Most seizures were generalized, and 61% of the patients had positive serology. One EEG was uninterpretable and another showed isolated spikes. Electroclinical agreement was considered to be satisfactory in 33 patients, and was better with the epileptic than with slow abnormalities. The existence of epileptiform EEG abnormalities confirmed clinically diagnosed epilepsy, but did not allow etiological diagnosis. Electroserological agreement was good in 24 patients. A significant association (Chi2, p=0.03) existed between slow focal abnormalities and positive cysticercosis serology. Conversely, no significant association was detected between epileptic patterns and serology results. Conclusion. – While the EEG alone clearly does not allow aetiological diagnosis, its joint use with clinical and biological results was a key element of the etiological and therapeutic discussion. When it shows focal abnormalities in a patient with epilepsy living in a high prevalence cysticercosis area, it confirms the clinical suspicion of neurocysticercosis. Morphological imagery alone can provide etiological information on the seizures by showing the nature and localization of the parenchymal lesions. [Copyright &y& Elsevier]

The treatment of status epilepticus (SE) in children with epilepsy depends on the epilepsy syndrome, in order to avoid worsening drugs such as IV barbiturates in severe myoclonic epilepsy in infancy (SMEI) (Dravet’s syndrome) or IV benzodiazepam in tonic SE of Lennox-Gastaut syndrome. Intensive care procedures should not be systematical in convulsive SE (CSE) and are not indicated in non-convulsive SE (NCSE). Generalized CSE mostly involve SMEI before 3 years of age, symptomatic generalized epilepsy and partial lesional epilepsy. Treatment is an emergency and relies on IV benzodiazepines and, if necessary, IV phenytoine using plasmatic concentrations for an optimal management. The partial CSE of partial lesional epilepsy can result in focal deficit and need the same treatment as generalized CSE. NCSE consist in absence and/or myoclonic SE and are often unrecognised during a long time until EEG is performed. They mostly involve myoclonic epilepsies and can be controlled by IV benzodiazepines. The frequency of partial NCSE is underestimated, particularly in infants. Diagnosis relies on video EEG and treatment is the same as that used in partial CSE. [Copyright &y& Elsevier]

The electroencephalogram (EEG), an easy-to-use and non invasive cerebral investigation, is a useful tool for diagnosis and early prognosis in newborn babies. In newborn full term babies manifesting abnormal clinical signs, EEG can point focal lesions or specific aetiology. EEG background activity and sleep organization have a high prognostic value. Tracings recorded over long period can detect seizures, with or without clinical manifestations, and differentiate them from paroxysmal non epileptic movements. The EEG should therefore be recorded at the beginning of the first symptoms, and if possible before any seizure treatment. When used as a neonatal prognostic tool, EEG background activity is classified as normal, abnormal (type A and type B discontinuous and hyperactive rapid tracing) or highly abnormal (inactive, paroxysmal, low voltage plus theta tracing). In such cases, the initial recording must be made between 12 and 48 h after birth, and then between 4 and 8 days of life. Severe EEG abnormalities before 12 h of life have no reliable prognostic value but may help in the choice of early neuroprotective treatment of acute cerebral hypoxia-ischemia. During presumed hypoxic-ischemic encephalopathy, unusual EEG patterns may indicate another diagnosis. In premature newborn babies (29–32 w GA) with neurological abnormalities, EEG use is the same as in term newborns. Without any neurological abnormal sign, EEG requirements depend on GA and the mother’s or child’s risk factors. Before 28 w GA, when looking for positive rolandic sharp waves (PRSW), EEG records are to be acquired systematically at D2–D3, D7–D8, 31–32 and 36 w GA. It is well known that numerous and persistent PRSW are related to periventricular leukomalacia (PVL) and indicate a bad prognosis. In babies born after 32 GA with clinically severe symptoms, an EEG should be performed before D7. Background activity, organization and maturation of the tracing are valuable diagnosis and prognosis indicators. These recommendations are designed (1) to get a maximum of precise informations from a limited number of tracings and (2) to standardize practices and thus facilitate comparisons and multicenter studies. [Copyright &y& Elsevier]

The electrophysiology can be considered as one of the most reliable assessment of the nervous system function during anaesthesia. For instance, the electroencephalogram (EEG) can be relatively easily simplified and adapted to the current practice of the neuro-anaesthesia or neuro-intensive medicine. Since approximately 10 years, some extremely simplified devices have been introduced, but they allowed only inaccurate assessment because of their too global analysis of the brain function. The monitoring of the true digitised EEG, based on a simplified brain mapping montage combined to the analysis in the frequency and the time domains corresponds to a new investigation tool: the simplified EEG or sEEG, which can be included in our usual monitors or anaesthesia and intensive care machines. This new sort of monitoring could give us valuable information about, first, the control of the peroperative consciousness and the nociceptive or not afferent inputs due to surgical stimulations, and, second, the detection of several particular physiopathologic states during neuro-anaesthesia (brain ischaemia, non-convulsive epilepsy, cerebral protection…). These different theoretical and practical topics are reviewed to try to define the possible preliminary rules of the use of the sEEG. [Copyright &y& Elsevier]

Objective. – To describe a specific electroclinical type of epileptic seizure in a patient with Rett syndrome.Patient and methods. – We present the case of a girl with Rett syndrome and epilepsy, whose seizures followed two differentiated phases, namely (a) a brief hypertonic onset with tonic-axial predominance, followed by (b) a posterior prolonged clinical absence. These two phases were associated, respectively, to a paroxystic desynchronisation or generalised rapid spikes discharges, followed by a critical slow activity.Conclusions. – The epileptic seizures described in this report have not been previously documented in Rett syndrome. We review and discuss pathophysiological hypotheses in the light of this and previously reported cases of the syndrome. [Copyright &y& Elsevier]

Les patients qui présentent une altération du niveau de conscience constituent un défi médical, éthique et scientifique majeur. Le diagnostic et le pronostic sont des éléments essentiels à prendre en compte pour une prise en charge optimale. Cliniquement pour évaluer leur état de conscience, nous utilisons l’échelle CRS. Celle-ci permet de différencier les différents niveaux de conscience (coma, état végétatif et état de conscience minimal) et donne des informations précieuses quant à la progression clinique. En revanche, cette échelle ne permet pas toujours de trancher avec certitude sur l’état de conscience et la réanimation de ces patients pose rapidement la question du pronostic. Il est donc important de compléter cette première exploration clinique par d’autres examens, comme les potentiels évoqués cognitifs. Cet examen présente l’avantage d’être non invasif et joue un rôle important pour diagnostiquer le niveau de conscience à l’aide de certaines mesures neurales de l’électroencéphalogramme. Ces mesures permettent après traitement et analyse de différencier l’état de conscience minimal de l’état végétatif et prédire l’état de conscience dans les six prochaines semaines en compilant des données cliniques et d’électroencéphalographie et ainsi répondre à la question du pronostic. Pour ces potentiels évoqués, nous utilisons un casque d’électroencéphalogramme comportant 256 électrodes ainsi que le paradigme « local-global ». Celui-ci s’inspire du « odd-ball » classique, où des stimuli rares s’intercalent de manière aléatoire dans une suite de stimuli fréquents et permet ainsi de discriminer le traitement conscient d’un traitement non conscient. Nous avons mis au point un ensemble de mesures dérivées à la fois des réponses cérébrales aux sons (paradigme « local-global ») et de l’état de « repos » (puissance spectrale, connectivité fonctionnelle, complexité). [ABSTRACT FROM AUTHOR]

Le diagnostic d'encéphalite chez les enfants suivis pour une encéphalopathie épileptique peut être difficile à établir. Décrire les modifications de l'électroencéphalogramme de ces enfants au cours d'un épisode d'encéphalite. Réaliser une recherche bibliographique des cas de récidive d'encéphalite et d'encéphalite aiguë chez des patients suivis pour une encéphalopathie épileptique. Étude descriptive de cohorte rétrospective. Critères d'inclusion : tous les enfants suivis pour une encéphalopathie épileptique, ayant présenté une encéphalite aiguë entre 2011 et 2018. Relecture des électroencéphalogrammes réalisés chez ces enfants avant l'encéphalite, au moment du diagnostic et après traitement. Évaluation des modifications électroencéphalographiques. Nous rapportons le cas de trois enfants suivis pour une encéphalopathie épileptique ayant présenté une encéphalite secondaire. Dans ces trois cas, on note lors de la phase aiguë de l'encéphalite une modification de l'activité de fond préexistante avec régression des patterns épileptiques, ainsi qu'un ralentissement de cette activité de fond. D'après ces résultats sur une faible cohorte rétrospective, en cas de suspicion clinique d'encéphalite chez un patient suivi pour une encéphalopathie épileptique, un ralentissement de l'activité de fond associé à une régression des patterns épileptiques préexistants est évocateur d'encéphalite aigu. [ABSTRACT FROM AUTHOR]

Introduction Les épilepsies idiopathiques (EI) regroupent des syndromes épileptiques hétérogènes [1] . L’EEG occupe une place importante dans le diagnostic positif des EI [2] . L’objectif de l’étude était de trouver des éléments distinctifs entre les différents syndromes épileptiques en se basant sur l’EEG. Méthodes Nous avons mené une étude prospective sur une période de 3 ans (2014–2016), incluant les patients présentant une EI. Tous nos patients ont bénéficié d’un enregistrement EEG. Nous avons précisé les données électriques des différents syndromes épileptiques. Résultats Cent-vingt-sept patients étaient suivis pour EI (100 patients présentaient une EI à crises généralisées tonicocloniques isolées (EI-CGTC), 22 patients étaient suivis pour une épilepsie myoclonique juvénile (EMJ), 3 patients pour épilepsie absence de l’enfant et 2 patients présentaient une épilepsie absence juvénile). Environ la moitié de nos patients avaient un EEG normal. L’absence d’anomalies inter critiques était surtout observée chez nos patients atteints d’EI-CGTC ( p = 0,036). En contre partie, les anomalies inter critiques généralisées, la réponse photo-paroxystique et les anomalies paroxystiques déclenchées par la HPN étaient plus observées dans le groupe des patients avec EMJ ( p = 0,000, 0,023, et 0,001 respectivement). Les anomalies inter-critiques focales à l’EEG étaient enregistrées au cours des différents syndromes ( p = 0,23). Conclusion La meilleure connaissance des principales caractéristiques électriques des différents syndromes d’EI pourrait améliorer la prise en charge diagnostique et thérapeutique des patients avec épilepsie. [ABSTRACT FROM AUTHOR]

Introduction L’encéphalopathie hépatique est une complication grave de la cirrhose hépatique et représente ainsi un enjeu thérapeutique et socioéconomique important. Sa survenue chez des patients non cirrhotique présentant une thrombose des veines extra-hépatiques est rare. Observation Nous rapportons le cas d’un homme âgé de 46 ans, sans antécédents pathologiques particuliers qui consulte pour désorientation temporospatiale. Son histoire de la maladie remonte à 1 mois avant son admission par la survenue d’un état d’agitation nocturne sans mouvements toniques ni cloniques d’une durée 30 min à 12 heures qui récidivent avec une fréquence quotidienne. L’examen neurologique ne montre pas de signes de localisation. L’évolution était marquée par la persistance de ces épisodes associés à une régression cognitive (MMSE : 20/30), des fausses reconnaissances, un ralentissement psychomoteur marqué et des troubles dysexécutifs qui retentissent sur sa vie quotidienne. L’imagerie par résonance magnétique a montré des anomalies de signal des noyaux bipallidales en hypersignal T1 et en isosignal T2 et Flair. L’électroencéphalogramme (EEG) a montré des complexes triphasiques : des ondes lentes triphasiques à prédominance antérieur avec une activité de fond ralentie et réactive à l’ouverture des yeux. Le diagnostic d’une encéphalopathie métabolique était suspecté. Le contrôle du bilan hépatique qui était initialement strictement normal, a montré une diminution du Taux de prothrombine à 50 % et le dosage de l’amoniémie était élevé à un taux de 267,7 UI/L. Le diagnostic d’encéphalopathie hépatique était confirmé. L’échographie abdominale a montré des signes d’hypertension portale avec un cavernome porte. Le patient était mis sous lactulose avec une nette amélioration. Conclusion Il faut toujours penser à l’encéphalopathie hépatique devant tout tableau de démence rapidement progressive et pratiquer un EEG même chez des patients non connus cirrhotiques. [ABSTRACT FROM AUTHOR]

Introduction L’épilepsie est une manifestation fréquente des tumeurs cérébrales. L’EEG occupe une place prépondérante au moment du diagnostic puisqu’il permet d’écarter les manifestations non épileptiques. L’objectif était de déterminer les anomalies électriques en fonction de la topographie, la profondeur et la malignité de la tumeur cérébrale. Méthodes Nous avons mené une étude prospective sur une période de 3 ans (2015–2017), incluant les patients présentant une épilepsie symptomatique d’une tumeur cérébrale. Tous nos patients ont bénéficié d’un enregistrement EEG. Résultats Vingt-cinq patients étaient inclus dans notre étude. La tumeur cérébrale était bénigne chez 15 patients et maligne dans le reste des cas. Le lobe frontal était le plus incriminé (72 %, versus 24 % pour le lobe temporal, 20 % pour le lobe pariétal et 4 % pour le lobe occipital). Une atteinte corticale était présente chez 88 % des malades. Les CE étaient focales dans 63 % des cas. L’EEG était sans anomalies dans 33,3 % des tumeurs bénignes et 40 % des tumeurs malignes. Des anomalies paroxystiques à type de p et PO étaient enregistrées surtout chez les patients avec tumeur bénigne (53,3 % versus 30 % des tumeurs malignes). Par contre, un ralentissement focal était enregistré surtout en cas de tumeur maligne (40 % versus 13 % des tumeurs bénignes). Ces anomalies inter critiques étaient focales dans 96 % des cas, de localisation antérieure dans la majorité des cas. Conclusion Les anomalies électriques peuvent varier en fonction de la topographie lésionnelle et de la nature de la tumeur. L’atteinte la plus caractéristique est la présence d’ondes lentes focales, qui sous-entendent l’existence d’une cellularité importante, et qui sont plus fréquentes en cas de tumeurs malignes. Les anomalies EEG se modifient dans le temps, en parallèle de la progression tumorale. D’où l’intérêt d’un suivi EEG, surtout pour distinguer les CE des manifestations non épileptiques. [ABSTRACT FROM AUTHOR]

Objectifs L’épilepsie focale migrante est une entité rare récente décrite pour la première fois en 1995. Seulement quelques cas ont été rapportés dans la littérature. Cependant, son diagnostic, son pronostic et sa prise en charge thérapeutique font l’objet de plusieurs études. Observation Il s’agit d’un nourrisson âgé de 3 mois et 15 jours aux antécédents d’une hospitalisation à la naissance pour hypotonie, des apnées et des crises épileptiques à type de clonies des membres et de révulsion oculaire. Il a été mis sous valproate de sodium et vitamine B6 mais le nourrisson continue à faire des crises de même sémiologie. L’examen clinique a objectivé une dysmorphie faciale, un phymosis et une cryptorchidie bilatérale. L’électroencéphalogramme (EEG) intercritique a montré un tracé symétrique mal organisé avec de nombreuses décharges paroxystiques d’ondes lentes rythmiques temporales gauches qui migrent en temporal droit. Le nourrisson a présenté une révulsion oculaire avec trouble de la vigilance. L’EEG critique objective le caractère migratoire avec des activités rythmiques thêta encochés de pointes en temporal droit, qui migrent en occipital droit puis en controlatéral. Discussion L’épilepsie focale migrante est caractérisée par l’apparition avant l’âge de 6 mois de crises électriques polymorphes quasi continues multifocales se déchargeant d’une manière indépendante et séquentielle sur les deux hémisphères donnant ainsi une expression polymorphe. Dans la plupart des cas aucune étiologie n’est identifiée, mais quelques études récentes ont mis en évidence une mutation génétique. Cliniquement cette maladie est caractérisée par un retard mental avec parfois une hypotonie majeure, une microcéphalie, une dysmorphie faciale ou une atrophie cérébrale et cérébelleuse. Les crises épileptiques sont souvent pharmacorésistantes bien qu’une réponse positive a été obtenue avec certaines médications. Conclusion Une meilleure connaissance de l’épilepsie focale migrante permet un diagnostic plus précoce et ainsi une meilleure prise en charge quoique le pronostic de cette maladie reste sombre. [ABSTRACT FROM AUTHOR]

L’EEG est un examen indispensable pour de nombreuses indications neurologiques chez l’adulte et l’enfant. Il n’est malheureusement pas accessible pour certains patients trop éloignés des laboratoires d’électrophysiologie réalisant cet examen. La télétransmission des EEG pourrait permettre de répondre à cette problématique. Pourtant, elle peine à se mettre en place en France, en grande partie du fait de contraintes financières. Les retours d’expériences sur le terrain (Bordeaux, Lille, Paris) et l’enquête de la pratique de la transmission des EEG à distance en France montrent les difficultés de fonctionnement et la nécessité de faire appel à une plus grande normalisation des processus. Certains acteurs de terrain en ont pris conscience et leur action confirme le caractère essentiel de l’implication des professionnels de santé dans les transformations de l’organisation des soins. Le financement des projets de télé-EEG reste difficile et peu connu des acteurs de santé. Il peut être initié, par des appels à projets classiques (PHRC) ou plus spécifiques (PFLSS, FEDER, FIR…), ou encore par les ARS régionales. En revanche, la pérennisation de ces financements n’est le plus souvent pas assurée, mettant en péril des organisations qui se sont développées grâce à l’initiative des acteurs de santé. Nous montrons que l’établissement de ces normes suppose une contribution de l’État dans un effort de normalisation des pratiques, essentiel à la pérennité des réseaux de santé. L’État doit dépasser son rôle de prescripteur des normes, pour endosser le rôle d’État-partenaire, capable d’accompagner les besoins du terrain, résolvant ainsi le paradoxe entre liberté des acteurs de terrain et normalisation. [ABSTRACT FROM AUTHOR]