Epilepsy and anomalies of neuronal migration: MRI and clinical aspects

Neuronal migration disorders are the result of disturbed brain development. In such disorders, neurons are abnormally located. In diagnosing these conditions, magnetic resonance imaging is superior to any other imaging technique. This enables us to improve our knowledge of the clinical correlates of neuronal migration. With reference to migrational disorder, a retrospective study of all 303 patients with epileptic seizures referred for magnetic resonance imaging during a 3-year period was performed, 13 patients (aged 12-41, mean age 27) were identified. They represent 4.3% of the entire study group. Of the patients with known epilepsy, 6.7% and of the mentally retarded, 13.7% had migrational disorders. Four patients had schizencephaly as the dominant finding, one was classified as hemimegalencephaly, 2 had isolated heterotopias, and 6 had localized pachy- and/or poly-microgyria. The clinical pictures are complex. Ectopias of grey matter are recognised foci of epilepsy, but from an epileptological and a clinical viewpoint little attention has been given to these disorders. The present study shows that malmigration is not rare in epilepsy patients, especially not in the mentally retarded.     

Classification of methods in transcranial Electrical Stimulation (tES) and evolving strategy from historical approaches to contemporary innovations

Transcranial Electrical Stimulation (tES) encompasses all methods of non-invasive current application to the brain used in research and clinical practice. We present the first comprehensive and technical review, explaining the evolution of tES in both terminology and dosage over the past 100 years of research to present day. Current transcranial Pulsed Current Stimulation (tPCS) approaches such as Cranial Electrotherapy Stimulation (CES) descended from Electrosleep (ES) through Cranial Electro-stimulation Therapy (CET), Transcerebral Electrotherapy (TCET), and NeuroElectric Therapy (NET) while others like Transcutaneous Cranial Electrical Stimulation (TCES) descended from Electroanesthesia (EA) through Limoge, and Interferential Stimulation. Prior to a contemporary resurgence in interest, variations of transcranial Direct Current Stimulation were explored intermittently, including Polarizing current, Galvanic Vestibular Stimulation (GVS), and Transcranial Micropolarization. The development of these approaches alongside Electroconvulsive Therapy (ECT) and pharmacological developments are considered. Both the roots and unique features of contemporary approaches such as transcranial Alternating Current Stimulation (tACS) and transcranial Random Noise Stimulation (tRNS) are discussed. Trends and incremental developments in electrode montage and waveform spanning decades are presented leading to the present day. Commercial devices, seminal conferences, and regulatory decisions are noted. We conclude with six rules on how increasing medical and technological sophistication may now be leveraged for broader success and adoption of tES.     

Hepatic Considerations in the Use of Antiepileptic Drugs

Summary: Virtually all of the major antiepileptic drugs (AEDs) can cause hepatotoxicity, although fatal hepatic reactions are rare. The mechanisms, incidences, and risk profiles for such reactions differ from drug to drug. With carbamazepine and phenytoin, hepatotoxicity may be due to drug hypersensitivity. Although the profiles of patients at risk have not been well-defined for these two antiepileptic drugs, it would appear from reports in the literature that older adolescents and adults are at higher risk than children of developing serious or fatal hepatotoxicity. Once hepatotoxicity develops, mortality rates are 10–38% with phenytoin and 25% for carbamazepine. The risk profile for valproate fatal hepatotoxicity has been more clearly defined. Those at primary risk of fatal hepatic dysfunction are children under the age of 2 years who are receiving multiple anticonvulsants and also have significant medical problems in addition to severe epilepsy. The risk is considerably lower for patients over the age of 2 years on valproate monotherapy. In contrast to the risk profile with other AEDs, adults receiving valproate as monotherapy have the lowest risk of hepatotoxicity. Fatal hepatic dysfunction coincident with valproate may be the result of aberrant drug metabolism. Concomitant use of AEDs that induce microsomal P450 enzymes (e.g., phenytoin and phenobarbital) may enhance the production of a toxic metabolite, and hence the greater risk of hepatotoxicity with polypharmacy.     

Vascular Malformations and Epilepsy: Clinical Considerations and Basic Mechanisms

Summary: Vascular malformations (VMs) are associated with epilepsy. The natural history of the various VMs, clinical presentation, and tendency to provoke epilepsy determine treatment strategies. Investigations have probed the mechanisms of epileptogenesis associated with these lesions. Electrophysiologic changes are associated with epileptogenic cortex adjacent to VMs. Putative pathophysiologic mechanisms of epileptogenesis include neuronal cell loss, glial proliferation and abnormal glial physiology, altered neurotransmitter levels, free radical formation, and aberrant second messenger physiology.     

Neonatal Seizures: Problems in Diagnosis and Classification

Summary: The clinical identification of neonatal seizures is critical for the recognition of brain dysfunction; however, diagnosis is often difficult because of the poorly organized and varied nature of these behaviors. Current classification systems are limited in their ability to communicate motor, autonomic, and electroencephalo-graphic features of seizures precisely and to provide a basis for uniform effective diagnosis, therapy, and determination of prognosis. Recent investigations of neonates, utilizing bedside electroencephalographic/polygraphic/ video monitoring techniques, have provided the basis for improved diagnosis and classification of seizures in the newborn. These studies have demonstrated that not all clinical phenomena currently considered to be seizures require electrocortical epileptiform activity for their initiation or elaboration. In addition, the specific clinical character of the phenomena considered to be seizures, the clinical state of the infant, and the character of the EEG indicate the probable pathophysiological mechanisms involved and suggest probable etiologies, prognosis, and therapy. Similarities between animal models that demonstrate reflex physiology and neonates with motor automatisms and tonic posturing suggest that these clinical behaviors may not be epileptic in origin but, rather, primitive movements of progression and posture mediated by brainstem mechanisms. Although not all clinical behaviors currently considered to be neonatal seizures may have similar pathophysiological mechanisms, they are clinically significant because they all indicate brain dysfunction.     

Valproate Monotherapy in the Management of Generalized and Partial Seizures

Summary: For decades, therapeutic tradition has promoted the concept of polypharmacy in the management of epilepsy. In recent years, however, studies have shown that, for most patients, monotherapy can provide comparable or better seizure control than administration of multiple anticonvulsants, while diminishing the potential for adverse reactions, drug interactions, and poor compliance. Valproate is an important monotherapeutic agent that is highly effective in the control of idiopathic primary and secondarily generalized epilepsies, and partial seizures that do not generalize. Comparative studies have found that valproate is at least as effective as phenytoin and carbamazepine in the treatment of generalized and partial seizures. Given the similar efficacy, other factors such as pharmacokinetics and side effects may therefore determine anticonvulsant selection for monotherapy.     

Carbamazepine Efficacy and Utilization in Children

Summary: Carbamazepine is effective for preventing partial and generalized tonic-clonic seizures in children. Although absence epilepsies are more common in children than adults, an estimated 80% of children with epilepsy have seizure types or epilepsies that are potentially responsive to carbamazepine. The differential diagnosis of ictal staring is an especially important issue in children because absence and atypical absence seizures are more prevalent in children than adults. Age-related pharmacokinetic differences and drug interactions are major considerations in children. On average, children have higher clearance rates of carbamazepine, shorter half-lives, and higher ratios of carbamazepine-10, 11-epoxide to carbamazepine than adults. In addition, children with severe epilepsy are more likely to require multiple-drug therapy, which can lead to complex drug interactions. When carbamazepine is administered along with valproate, drug protein binding interactions can cause intermittent side effects.     

Un nouveau cadre conceptuel de travail pour la psychiatrie

In an attempt to place psychiatric thinking and the training of future psychiatrists more centrally into the context of modern biology, the author outlines the beginnings of a new intellectual framework for psychiatry that derives from current biological thinking about the relationship of mind to brain. The purpose of this framework is twofold. First, it is designed to emphasize that the professional requirements for future psychiatrists will demand a greater knowledge of the structure and functioning of the brain than is currently available in most training programs. Second, it is designed to illustrate that the unique domain which psychiatry occupies within academic medicine, the analysis of the interaction between social and biological determinants of behavior, can best be studied by also having a full understanding of the biological components of behavior.     

Special Pharmacokinetic Considerations in Children

Summary: Pediatric patients have greater degrees of pharmacokinetic variability and unpredictability than adults. This variability results from the effects of pharmacogenetics, age and growth, prior and current comedication, and disease. Newborns with seizures have the least predictable dosage requirements, and their needs change as drug-eliminating mechanisms mature in the neonatal period. Infants have the highest relative capacities to eliminate antiepileptics of any age group and require the largest relative doses. In addition to age-related trends, children demonstrate the same drug-specific, pharmacokinetic phenomena that adults do, including nonlinear phenytoin elimination, nonlinear valproate binding, and autoinduction of carbamazepine. Intercurrent illness and drug interactions further modify the age-related pharmacokinetic patterns in children and make dosage requirements even more unpredictable. Recent studies have shown that febrile illness can affect drug elimination, sometimes decreasing drug levels by 50% or more. Intermittent treatment with benzodiazepines administered either orally or rectally can be an important adjunct and help minimize this type of problem for children with marginally controlled epilepsy. Intermittent benzodiazepines are also helpful for children who have febrile seizures and who need only occasional antiepileptic protection.     

Clobazam for Treatment of Intractable Epilepsy: A Critical Assessment

Summary: Clobazam (CLB), a 1,5-benzodiazepine, is a remarkably effective add-on drug for individual patients with refractory partial epilepsy. CLB has an excellent safety record. As with all benzodiazepines used for treating epilepsy, sedation and withdrawal effects, together with the development of tolerance, limit its usefulness. Recent efforts to prevent or reverse tolerance with intermittent administration of CLB or periodic injection of a benzodiazepine antagonist, flumazenil, are encouraging and justify further investigations.     

Le surgissement de l'originaire et le « retrait hallucinatoire » dans les formes délirantes de l'éveil de coma

The clinical investigation of delirious and hallucinatory states during the awakening from a coma reveals hallucinated representations of a polymorphic nature. The diversity of their contents suggests the implication of differentiated etio-pathogenic processes. The assumption followed here, based on the conceptualizations of P. Aulagnier, is that the emergency care awakening traumatism causes a prevailing reinvestment of various operating modes, from the recovery of a “pictographic production” due to the abolition of conscience, to the fantastical scenario characterising primary education that remobilises and upsets the identity bearing layers in which the essential moments of the instinctual history were elaborated. These symptomatic constructions thus express this “in-more” generated by the psychotic processes which combine the double movement of a regression and of a “redeployment” of the traces of the Primal. This second period fulfils the paramount requirement of a primitive development of the coma awakening experience following the “postulate” of the dominance of the Primal according to which any psychic object is seen initially metabolized in a pictographic representation. The stratification noted within these dreamlike formations reveals: on the one hand modes of composition of images similar to those of the night dream; and on the other a deployment of various imagos of archaic states of the parcelled out body; and finally “psychic residues” that re-appear in the form of “parasitic” reminiscences, analysable as resurgences of psychic activities resulting from the coma phase. Thus a representation of the data of the Primal is then generated and although these data are psychic they remain forever heterogeneous and external to the Unconscious and to the I. The common clinical term which supports this analysis is “hallucinated feeling” which, according to Aulagnier, emerges sometimes within a schizophrenic patient which could be understood as equivalent to an autistic withdrawal which we suppose to be here at the heart of the deliriousness of the awakening from the coma. Thus the proposal that two etio-pathogenic logics are at work in these acute episodes: 1/ one that is initiated in a movement of decomposition of the I, due to the multiple traumatic effects of the primary affection and of the emergency care awakening process, balanced by the variations of the state of consciousness of the patient. At the time of this regression the projective mechanism, combined with other defences such as rejection or cleavage, reveals scenarios in the psychic space which mobilize images of the body and perceptive or mnemonic fragments. 2/ the other trajectory is comparable to this dynamics of the “withdrawal in the hallucination”. The re-establishment of the specific processes of the primary and secondary agencies imposes a requirement of specific psychic work consisting in metabolizing this resurgence of the pictographic representations that originate in the (quasi) nothing of the coma.     

An Overview of Pediatric Seizure Disorders and Epileptic Syndromes

Summary: Seizures are common in infants and children and must be differentiated from a wide variety of other neurological and nonneurological disorders which include episodic disturbances of behavior. If the diagnosis is clear, then one must decide if the seizure is an isolated event and unlikely to recur (as are many afebrile generalized convulsive seizures in early childhood), a symptom of underlying cerebral pathology, or part of an epileptic syndrome. The latter may be a potentially lethal neurodegenerative disease or a benign epilepsy with excellent outcome. This review will discuss the various aspects of epilepsy in the pediatric age group, emphasize the benign nature of most seizures in children (including many forms of partial, or focal, seizures), and present an overview of the more serious epileptic syndromes. The myoclonic epilepsies will be used as a model to illustrate the wide scope of epileptic phenomena in infants and children.     

Clinically Significant Carbamazepine Drug Interactions: An Overview

Summary: Knowledge of the principles of drug action and distribution contributes to an understanding of the occurrence of drug interactions. The pharmacologic action of most drugs is postulated to occur by the formation of a drug-receptor complex at the site of action that is capable of altering the physiologic response of the target system. The therapeutic response observed depends on the sum of the numerous factors that can affect the disposition pattern of a drug. In an individual, the response to a given drug dose remains relatively constant, but in a large population, a fixed dose can produce a range of plasma concentrations and therefore varied clinical responses. For most drugs, there is a linear relationship between the total dose and the plasma concentration achieved at steady state. Saturation, or zero-order, kinetics accounts for nonlinear increases in drug concentration with dosage increase. Drug-drug interactions with carbamazepine include several types. (1) Autoinduction of carbamazepine metabolism increases the carbamazepine clearance rate, decreases the half-life, and decreases serum concentrations; the clinician must reevaluate a patient's serum levels at 4 to 6 weeks after initiation of therapy. (2) Carbamazepine induces the metabolism of other antiepileptic drugs, enhancing the clearance of phenytoin, primidone, valproic acid, clonazepam, and ethosuximide. (3) Other drugs added to the epileptic patient's drug regimen may induce the metabolism of carbamazepine, causing increased serum concentrations. (4) Inhibition of carbamazepine metabolism by other drugs can also occur; symptoms of drug intoxication rapidly follow. Interactions occur between carbamazepine and macrolide antibiotics, cimetidine, propoxyphene, and isoniazid. Drug-drug interactions are preventable. It is the responsibility of every physician to be alert to the potential for their occurrence whenever a change in the epileptic patient's drug regimen is made.     

Epileptogenesis and the Immature Brain

Summary: Epidemiological studies indicate that the incidence of seizures is highest early in life. This report discusses the experimental data derived from studies of focal epileptogenesis of the immature brain in tandem with ongoing maturational changes. During development, neurons have characteristic neurophysiological properties. Local interictal discharges are long in duration, lack a stereotypic morphology, and have limited fields. Yet the immature brain is very susceptible to the development of bilateral, although asynchronous, seizures and status epilepticus induced by amygdala kindling or by convul-sant drugs. This increased seizure susceptibility may be due to a functional immaturity of a substantia nigra, GABA-sensitive output system. The morbidity of convulsions occurring early in life may not be as grave as previously thought in terms of subsequent acquisition of "normal" developmental milestones. The propensity to develop recurrent convulsions in adulthood is not related to the severity of a single seizure in infancy. Although multiple severe seizures may predispose animals to the development of seizures later in life, this is not a unique feature of the immature brain, since it also occurs in the adult brain. Finally, there is evidence that the immature brain may respond to anticonvulsant drugs differently from its mature counterpart; these findings emphasize the need to develop new antiepileptic therapies that take into account the maturational state of the brain.     

La passion de Torquemada et le terrorisme islamique : quelques points de comparaison

This original research compares the doctrinal, psychopathological and operational standpoints of the 15th century Spanish Inquisition (Torquemada) with those of radical Islamism from 1988 to 2005 (Al-Qaeda). The following are reviewed: (a) the main texts codifying the procedure for conducting the criminal investigation of a Holy Office trial (Directorium inquisitorum); (b) the life and work of the grand inquisitor Tomás de Torquemada (1420–1498); (c) the psychopathological relations between passion (passionate psychoses, passionate idealism, paranoid personality) and fanaticism; (d) “the madmen, the enlightened and the criminals” of Islamic terrorism; (e) the cognitive and emotional motives for engagement in the jihadist radicalization of young people; (f) the common principles of monotheistic fanaticism (Inquisition, Al-Qaeda) and the particular dogmas of Islamic terrorism in our time; (g) the operating modes of the Inquisition and the Jihadist holy war. The author concludes that the rigour and seriousness of the inquisitorial judicial procedure, which was precise, individual and personalized, contrasts with the revolutionary pamphlets of Al-Qaeda, which only provide broad guidelines for the modus operandi of the fight against infidels, who are usually random victims.     

Claustration et collectionnisme : réflexions à propos d’un cas de syndrome de Diogène avec vols kleptomaniaques et vengeurs

Social withdrawal is a pathognomonic behaviour that is consistently associated with mental illnesses. Compulsive hoarding can also be interpreted as a pathological behaviour, even when it does not involve kleptomania. Diogenes syndrome (DS) was first described in 1975, and is characterized by both behaviours - social withdrawal and compulsive hoarding. Even though it is often the manifestation of a psychiatric condition, its aetiology is diverse. The most frequent ones are however: dementia, schizophrenia and mental retardation. In this study, we describe an atypical case presenting with DS. Il consists of a young man, seen in a forensic setting, who had been diagnosed with kleptomania in the past, presents with compulsive hoarding, and whose recent thefts were fuelled by revenge. Finally, to our knowledge, the way social withdrawal is viewed is seldom taken into account. We analyse its implication on social withdrawal.     

Neurological soft signs and schizophrenia: a review of current knowledge

Schizophrenia is a frequent and disabling disorder emerging during adolescence or early adulthood. The identification of underlying processes has been hampered by the complex clinical expression and the probable etiological heterogeneity. The frequency of neurological soft signs (NSS) in patients with schizophrenia and their presence early in life (during the first two years) in high risk subjects support the hypothesis that schizophrenia is a "brain disease" reflecting pre- or perinatal insults during development. The growing interest for NSS has lead to multiple studies that are often difficult to compare. The objective of this review is to summarize the current knowledge on NSS, methodological issues and the future perspectives.