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International audience; We report on a 7-year-old female who presented paroxysmal episodes of loss of consciousness with clonic movements. The electroencephalogram (EEG) evidenced diffuse slow wave activations, with no symptoms. Epilepsy was suspected but antiepileptic drugs were ineffective. Video-EEG monitoring revealed that the syncope was triggered by stretching with a tachycardia that started during the stretch maneuver and diffuse slow waves on the EEG 2s before the symptoms. Stretch syncope can result in striking manifestations with subcortically driven clonic movements that can be mistaken for signs of epilepsy. Stretching might lead to transient hypoxia of the brainstem; in turn, this might activate the thalamocortical loop and thus generate cardiovascular changes, EEG slow waves, and physical manifestations.

Electroencephalography is the only clinically available technique that can address the premature neonate normal and pathological functional development week after week. The changes in the electroencephalogram (EEG) result from gradual structural and functional modifications that arise during the last trimester of pregnancy. Here, we review the structural changes over time that underlie the establishment of functional immature neural networks, the impact of certain anatomical specificities (fontanelles, connectivity, etc.) on the EEG, limitations in EEG interpretation, and the utility of high-resolution EEG (HR-EEG) in premature newborns (a promising technique with a high degree of spatiotemporal resolution). In particular, we classify EEG features according to whether they are manifestations of endogenous generators (i.e. theta activities that coalesce with a slow wave or delta brushes) or come from a broader network. Furthermore, we review publications on EEG in premature animals because the data provide a better understanding of what is happening in premature newborns. We then discuss the results and limitations of functional connectivity analyses in premature newborns. Lastly, we report on the magnetoelectroencephalographic studies of brain activity in the fetus. A better understanding of complex interactions at various structural and functional levels during normal neurodevelopment (as assessed using electroencephalography as a benchmark method) might lead to better clinical care and monitoring for premature neonates.

Summary: Purpose: To analyze respiratory alterations and effects on SaO2 caused by vagus nerve stimulation (VNS) in children with epilepsy. Methods: Polysomnographic recordings, including electroencephalography, thoracoabdominal distention, nasal airflow, SaO2, and VNS artifact were evaluated in 10 children with pharmacoresistant epilepsy treated with VNS. Results: Each VNS caused a significant increase in respiratory frequency (p < 0.05) throughout the stimulation period and a decrease in thoracoabdominal-distention amplitude (p < 0.05), especially at the beginning of the stimulation. These respiratory alterations induced a decrease in SaO2 from 1 to 5%. The effects of VNS on respiration differed significantly between rapid-eye-movement (REM) and non-REM (NREM) sleep states. Conclusions: VNS caused a pronounced change in respiration in children with epilepsy, and this induced a decrease in SaO2. It is possible that VNS has a neuroprotective effect, and this possibility calls for further investigation.

Summary Objective This case study aims to demonstrate that spatiotemporal spike discrimination and source analysis are effective to monitor the development of sources of epileptic activity in time and space. Therefore, they can provide clinically useful information allowing a better understanding of the pathophysiology of individual seizures with time- and space-resolved characteristics of successive epileptic states, including interictal, preictal, postictal, and ictal states. Methods High spatial resolution scalp EEGs (HR-EEG) were acquired from a 2-year-old girl with refractory central epilepsy and single-focus seizures as confirmed by intracerebral EEG recordings and ictal single-photon emission computed tomography (SPECT). Evaluation of HR-EEG consists of the following three global steps: (1) creation of the initial head model, (2) automatic spike and seizure detection, and finally (3) source localization. During the source localization phase, epileptic states are determined to allow state-based spike detection and localization of underlying sources for each spike. In a final cluster analysis, localization results are integrated to determine the possible sources of epileptic activity. The results were compared with the cerebral locations identified by intracerebral EEG recordings and SPECT. Results The results obtained with this approach were concordant with those of MRI, SPECT and distribution of intracerebral potentials. Dipole cluster centres found for spikes in interictal, preictal, ictal and postictal states were situated an average of 6.3 mm from the intracerebral contacts with the highest voltage. Both amplitude and shape of spikes change between states. Dispersion of the dipoles was higher in the preictal state than in the postictal state. Two clusters of spikes were identified. The centres of these clusters changed position periodically during the various epileptic states. Conclusion High-resolution surface EEG evaluated by an advanced algorithmic approach can be used to investigate the spatiotemporal characteristics of sources located in the epileptic focus. The results were validated by standard methods, ensuring good spatial resolution by MRI and SPECT and optimal temporal resolution by intracerebral EEG. Surface EEG can be used to identify different spike clusters and sources of the successive epileptic states. The method that was used in this study will provide physicians with a better understanding of the pathophysiological characteristics of epileptic activities. In particular, this method may be useful for more effective positioning of implantable intracerebral electrodes.

Summary Coregistration of EEG-near infrared spectroscopy (NIRS) is a recent technique used to analyse changes in both electrical and local hemodynamic activities. Here, we describe some technical aspects of simultaneous EEG-NIRS signal acquisition focusing on recent EEG-NIRS sensors, notably the Electroptode ® ™. Advantages and disadvantages of simultaneous EEG-NIRS acquisition are discussed in comparison to other common techniques in epilepsy. Most important recent results are presented and discussed, notably those providing new insights into the mechanisms propelling neurons to synchronize, resulting in inter-critical spikes and different types of seizures.

We would like to alert the medical community to pos-sible respiratory side effects of vagal nerve stimulation(VNS) during the treatment of nonsurgical refractorypartial epilepsy. We observed hypopneic–polypneic epi-sodes during sleep in a 9-year-old girl with epilepsy withcontinuous spike–waves during slow sleep (CSWSS)syndrome. These events were time-locked to each periodof VNS stimulation and occurred without any modifica-tion of cardiac frequency. VNS may elicit a reduction of25–50% in seizure frequency in both adults and childrenwith intractable epilepsy (1). Adverse side effects andcomplications of VNS were few and mostly transient andwere reported in adult patients only. They includehoarseness, neck pain, hypersalivation, cough, and short-ness of breath (“air-missing”) sensations during physicalexercise. These sensations might be related to the in-crease in end-expiratory volume observed in some pa-tients receiving stimulation at high intensity. In contrastto the common observation that VNS modifies the respi-ratory pattern in animals, only one study has reportedalterations in the respiratory pattern in humans (2).In the present case, the mother’s pregnancy wasmarked by fetal death of a twin sister at 24 weeks ofpostconceptional age. Birth was uneventful at 36 weeksof gestational age. Systematic transfontanellar ultrasoundanalysis revealed bilateral diffuse periventricular leuko-malacia. At age 2 years, she had right tonic partial sei-zures with loss of contact, and magnetic resonanceimaging (MRI) evidenced a left parietal extended isch-emic lesion.At age 5 years, her seizures changed and increased infrequency: during daytime, they were characterized byabsence seizures associated with mild and inconstant ato-nia (up to one seizure every 2–3 min). Sleep EEGshowed CSWSS. Over the course of the following year,she was treated unsuccessfully with seven different an-tiepileptic drugs (AEDs). A ketogenic diet also was in-effective. She was considered an ineligible candidate forsurgery because of the extent of the left sylvian ischemiclesion.At age 6 years, a neurocybernetic prosthesis (Cyberon-ics, Houston, Texas U.S.A.) was implanted. The stimu-lation allowed a drug-free period of 2 months, duringwhich there was an initial seizure-free period of 6 weeks.Then absences reappeared but were less numerous thanbefore implantation. Subsequently she was given la-motrigine (LTG) with VNS. Despite the use of variousAED combinations and changes in stimulation param-eters over the next year, the absences persisted.At age 6