C. A. Tassinari

Encephalopathy with electrical status epilepticus during slow sleep or ESES syndrome including the acquired aphasia

Encephalopathy with electrical status epilepticus during sleep or ESES is an age-dependent and self-limited syndrome whose distinctive features include a characteristic age of onset (with a peak around 4-5 years), heterogeneous seizures types (mostly partial motor or unilateral seizures during sleep and absences or falls while awake), a typical EEG pattern (with continuous and diffuse paroxysms occupying at least 85% of slow wave sleep) and a variable neuropsychological regression consisting of IQ decrease, reduction of language (as in acquired aphasia or Landau-Kleffner syndrome), disturbance of behaviour (psychotic states) and motor impairment (in the form of ataxia, dyspraxia, dystonia or unilateral deficit). Despite the long-term favourable outcome of epilepsy and status epilepticus during sleep (SES), the prognosis is guarded because of the persistence of severe neuropsychological and/or motor deficits in approximately half of the patients. No specific treatment has been advocated for this syndrome, but valproate sodium, benzodiazepines and ACTH have been shown to control the seizures and the SES pattern in many cases, although often only temporarily. Subpial transection is proposed in some instances as in non-regressive acquired aphasia. Recent data support the concept that ESES syndrome may include a large subset of developmental or acquired regressive conditions of infancy.

Epilepsy and EEG findings in males with fragile X syndrome

Summary: Purpose and Methods: One hundred and ninety‐two fragile X male patients were investigated for seizures and EEG findings, 168 in a retrospective and 24 in another prospective study, to characterize the natural history of seizures, epilepsy, and EEG abnormalities in males with this syndrome.

Transcranial magnetic stimulation and epilepsy

Epileptic conditions are characterized by an altered balance between excitatory and inhibitory influences at the cortical level. Transcranial magnetic stimulation (TMS) provides a noninvasive evaluation of separate excitatory and inhibitory functions of the cerebral cortex. In addition, repetitive TMS (rTMS) can modulate the excitability of cortical networks. We review the different ways that TMS has been used to investigate pathophysiological mechanisms and effects of antiepileptic drugs in patients with epilepsy and epileptic myoclonus. The safety of different TMS techniques is discussed too. Finally, we discuss the therapeutic prospects of rTMS in this field.

Central pattern generators for a common semiology in fronto-limbic seizures and in parasomnias. A neuroethologic approach.

Central pattern generators (CPGs) are genetically determined neuronal aggregates in the mesencephalon, pons and spinal cord subserving innate motor behaviours essential for survival (feeding, locomotion, reproduction etc.). In higher primates CPGs are largely under neocortical control. We describe how certain motor events observed in parasomnias and epileptic seizures could have similar features and resemble motor behaviours, which can be the expression of the same CPG. Both epilepsy and sleep can lead to a temporary loss of control of neomammalian cortex that facilitates through a common platform (arousal) the emergences of stereotyped inborn fixed action patterns. Therefore we suggest that, independently from the nature of the trigger, be it a seizure or a parasomnia, the same CPGs can be involved, “caught up”, leading to a common motor semiology (the “Carillon theory”).

Impaired facial emotion recognition in early-onset right mesial temporal lobe epilepsy.

Background: Anteromedial temporal lobe regions, particularly the amygdala, participate in the recognition of emotions from facial expressions. The authors studied the ability of facial emotion recognition (ER) in subjects with symptomatic epilepsy, evaluating whether mesial temporal lobe damage is related to an impairment in the recognition of specific emotions and whether the onset of seizures in a critical period of life could prevent the development of ER. Methods: Groups included patients with temporal lobe epilepsy (TLE) with MRI evidence of mesial temporal sclerosis (MTS) (n = 33); patients with TLE with MRI evidence of temporal lobe lesions other than MTS (n = 30); and patients with extratemporal epilepsy (n = 33). Healthy volunteers (n = 50) served as controls. ER was tested by matching a facial expression with the name of one of the following basic emotions: happiness, sadness, fear, disgust, and anger. A face-matching task was used to control visuoperceptual abilities with face stimuli. Results: No subject showed deficits in the face-matching task. ER was impaired in patients with right MTS, especially for fearful faces. Patients presenting left MTS, right or left temporal lobe lesions other than MTS, or extratemporal seizure foci showed ER performances similar to controls. In all subjects with right TLE, the degree of emotion recognition impairment was related to age at first seizure (febrile or afebrile) and age at epilepsy onset. Conclusions: Early-onset right-sided mesial temporal lobe epilepsy is the key substrate determining a severe deficit in recognizing emotional facial expressions, especially fear.

Permutation entropy to detect vigilance changes and preictal states from scalp EEG in epileptic patients. A preliminary study

Permutation entropy (PE) was recently introduced as a very fast and robust algorithm to detect dynamic complexity changes in time series. It was also suggested as a useful screening algorithm for epileptic events in EEG data. In the present work, we tested its efficacy on scalp EEG data recorded from three epileptic patients. With a receiver operating characteristics (ROC) analysis, we evaluated the separability of amplitude distributions of PE resulting from preictal and interictal phases. Moreover, the dependency of PE on vigilance state was tested by correlation coefficients. A good separability of interictal and preictal phase was found, nevertheless PE was shown to be sensitive to changes in vigilance state. The changes of PE during the preictal phase and at seizure onset coincided with changes in vigilance state, restricting its possible use for seizure prediction on scalp EEG; this finding however suggests its possible usefulness for an automated classification of vigilance states.SommarioÈ stato recentemente introdotto un algoritmo denominato Permutation Entropy (PE) a cui gli autori Bandt e Pompe (2002) attribuiscono due caratteristiche interessanti: la robustezza e la relativa rapidità di implementazione, proprietà entrambe utili nell’individuazione delle variazioni di complessità in serie temporali. Sulla scia di un iniziale ottimismo, la PE è stata suggerita come un possibile ausilio di ricerca su dati elettroencefalografici relativi a crisi epilettiche. Un primo obiettivo del nostro studio era testare l’efficacia dell’algoritmo, su dati elettroencefalografici di scalpo, registrati da 3 pazienti epilettici. Mediante l’applicazione di una ROC (Receiver Operating Characteristics) analisi abbiamo valutato la separabilità delle distribuzioni delle ampiezze di PE, rispettivamente per la fase preictale per quella interictale, su ogni registrazione di scalpo. Il secondo obiettivo è stato quello di indagare le eventuali correlazioni sussistenti fra l’andamento della PE e gli stati di vigilanza. Troviamo una buona separabilità fra le curve di dati preictali e interictali di ciascun paziente, seppure è evidente che la PE sia sensibile al cambio di stati di vigilanza, poiché spesso l’inizio di un evento accessuale era concomitante a cambi di stati di vigilanza. Alla luce di queste osservazioni, concludiamo che al momento non è possibile valutare l’affidabilità della PE come algoritmo predittore di crisi su dati elettroencefalografici di superficie, mentre appare sicuramente più attendibile come classificatore automatico degli stati di vigilanza.

Autosomal Dominant Lateral Temporal Epilepsy: Clinical Spectrum, New Epitempin Mutations, and Genetic Heterogeneity in Seven European Families

Summary:  Purpose: To describe the clinical and genetic findings of seven additional pedigrees with autosomal dominant lateral temporal epilepsy (ADLTE).

Effects of chronic levodopa and pergolide treatment on cortical excitability in patients with Parkinson's disease: a transcranial magnetic stimulation study

OBJECTIVES Transcranial magnetic stimulation was used to assess the effects of chronic levodopa and pergolide treatment on motor cortex excitability in Parkinson disease (PD). METHODS Motor thresholds, intracortical inhibition and facilitation were studied at baseline and after 6 and 12 months of therapy in 10 PD patients and compared to 7 age-matched controls. RESULTS At baseline, there was significantly less intracortical inhibition with only a slight reduction of intracortical facilitation in PD as compared to controls. Relative to pretreatment condition, levodopa restored intracortical inhibition for 12 months while pergolide did not. Intracortical facilitation was always within the normal range. Motor thresholds were unchanged in both groups of patients over 12 months. Clinically, levodopa and pergolide improved motor Unified Parkinsons disease rating scale (UPDRS) scores at 6 months but only levodopa maintained benefit at 12 months as compared to baseline. CONCLUSIONS Levodopa and pergolide differentially affected cortical inhibitory circuits at 12 months. The progressive deterioration of restored intracortical inhibition with pergolide may be due to the development of tolerance and down-regulation of dopamine receptors.

Encephalopathy with status epilepticus during slow sleep: “The Penelope syndrome”

ESES (encephalopathy with status epilepticus during sleep) is an epileptic encephalopathy with heterogeneous clinical manifestations (cognitive, motor, and behavioral disturbances in different associations, and various seizure types) related to a peculiar electroencephalography (EEG) pattern characterized by paroxysmal activity significantly activated during slow sleep—that is, a condition of continuous spikes and waves, or status epilepticus, during sleep. The pathophysiologic mechanisms underlying this condition are still incompletely understood; recent data suggest that the abnormal epileptic EEG activity occurring during sleep might cause the typical clinical symptoms by interfering with sleep‐related physiologic functions, and possibly neuroplasticity processes mediating higher cortical functions such as learning and memory consolidation. As in the myth of Penelope, the wife of Odysseus, what is weaved during the day will be unraveled during the night.

Transcranial magnetic stimulation in epileptic patients Usefulness and safety

We studied 58 patients with partial or generalized epilepsy who had transcranial magnetic stimulation (TMS) of the brain motor regions. Short-term monitoring disclosed that the stimulation did not provoke seizures or EEG changes in any patient. Long-term follow-up disclosed that the epileptic condition was not made worse by TMS. TMS, as currently used for monitoring conduction in central motor pathways, does not induce seizures in drug-treated epileptic patients.