The main objective of this paper is to examine evidence for the concept that epileptic activity should be envisaged in terms of functional connectivity and dynamics of neuronal networks. Basic concepts regarding structure and dynamics of neuronal networks are briefly described. Particular attention is given to approaches that are derived, or related, to the concept of causality, as formulated by Granger. Linear and non-linear methodologies aiming at characterizing the dynamics of neuronal networks applied to EEG/MEG and combined EEG/fMRI signals in epilepsy are critically reviewed. The relevance of functional dynamical analysis of neuronal networks with respect to clinical queries in focal cortical dysplasias, temporal lobe epilepsies, and “generalized” epilepsies is emphasized. In the light of the concepts of epileptic neuronal networks, and recent experimental findings, the dichotomic classification in focal and generalized epilepsy is re-evaluated. It is proposed that so-called “generalized epilepsies,” such as absence seizures, are actually fast spreading epilepsies, the onset of which can be tracked down to particular neuronal networks using appropriate network analysis. Finally new approaches to delineate epileptogenic networks are discussed.
The incidence of epilepsy in the elderly has increased steadily over the last few decades. In some industrialized countries, one-third of the population is expected to be over the age of 65 in 2030. Therefore, we will face a dramatic increase in the number of elderly patients with epilepsy, many of whom will likely present comorbidities. This increase will put a heavy burden on health care and pension systems. This article focuses on epidemiology, diagnosis and treatment in epilepsies in the elderlies and outlines current research as well as future requirements for research. The diagnosis of epilepsy in the elderly can be difficult and may require long-term video-EEG monitoring. Stroke is the most frequent etiology in epilepsies in the elderlies. Status epilepticus in acute symptomatic epilepsies often results in fatality and may become an increasing health problem. The article also describes the current strategies in antiepileptic drug treatment and epilepsy surgery in the elderly. Novel antiepileptic drugs are necessary as current antiepileptics have strong interaction potentials and harmful side effects, making them ill-suboptimal for treating epilepsy in the elderly.
The prevalence and incidence of epilepsies in elderly is high. Due to demographic development, the portion of elderly patients with epilepsy will continue to rise over the next decades. In this study, we aimed to investigate seizure semiology, etiology, comorbidity, and therapy in elderly patients dependent on onset of epilepsy and in comparison with younger patients. In a prospective multicentre study, 202 epilepsy patients were included in a consecutive manner and subdivided into three groups (group A1: >65 years, onset of epilepsy after the age of 65 years; group A2: >65 years with early onset epilepsy, seizure onset before the age of 50 years; and group B: <50 years with epilepsy). Clinical data with respect to epilepsy, seizures, comorbidity, etiology, and anti-epileptic drug (AED) therapy were assessed using a questionnaire developed especially for these patient groups and filled out by the physicians. The clinical profile with regard to etiology, postictal conditions, and comorbidities clearly depends on the age of the patients and age of onset of epilepsy. Patients with an epilepsy onset after 65 years need lower doses of AEDs, gain better seizure control and have more concomitant diseases than younger patients or elderly epilepsy patients with early-onset epilepsy.