Olfactory stimulation induces delayed responses in epilepsy

Precipitation and inhibition of seizures and epileptic discharges by sensory stimuli are receiving increasing attention because they provide insight into natural seizure generation in human epilepsies and can identify potential nonpharmacological therapies. We aimed to investigate modulation (provocation or inhibition) of epileptiform discharges (EDs) in mesial temporal lobe epilepsy (MTLE) versus idiopathic generalized epilepsy (IGE) by olfactory stimulation (OS) compared with standard provocation methods. The underlying hypothesis was that any response would be more likely to occur in MTLE, considering the anatomical connections of the temporal lobe to the olfactory system. This multicenter, international study recruited patients with either MTLE or IGE who were systematically compared for responses to OS using an EEG/video-EEG protocol including a 30-min baseline, twice 3-min olfactory stimulation with ylang-ylang, hyperventilation, and intermittent photic stimulation. The 95% confidence interval (CI) for the baseline EDs in each patient was calculated, and modulation was assumed when the number of EDs during any 3-min test period was outside this CI. A total of 134 subjects (55 with MTLE, 53 with IGE, and 26 healthy controls) were included. Epileptiform discharges were inhibited during OS in about half the patients with both MILE and IGE, whereas following OS, provocation was seen in 29.1% of patients with MILE and inhibition in 28.3% of patients with IGE. Olfactory stimulation was less provocative than standard activation methods. The frequent subclinical modulation of epileptic activity in both MTLE and IGE is in striking contrast with the rarity of reports of olfactory seizure precipitation and arrest. Inhibition during OS can be explained by nonspecific arousal. The delayed responses seem to be related to processing of olfactory stimuli in the temporal lobe, thalamus, and frontal cortex. (C) 2016 Elsevier Inc. All rights reserved

Bradicardia como manifestação epiléptica em epilepsia temporal: relato de caso Bradycardia during temporal lobe seizure: case report

Descrevemos um caso de arritmia cardíaca como manifestação epiléptica. A monitorização video-eletrencefalográfica de uma paciente com 34 anos de idade que apresentava episódios de perda de consciência permitiu a detecção de períodos de assistolia como principal manifestação clínica, exigindo a implantação de marca-passo. O registro eletrencefalográfico concomitante mostrou atividade rítmica a 6-7 Hz de projeção na região temporal esquerda. A ressonância magnética mostrou lesão expansiva no giro para-hipocampal esquerdo. Alterações do ritmo cardíaco como taquicardia sinusal são frequentes em crises epilépticas. A descrição de bradicardia e/ou assistolia é rara. As conexões das estruturas mesiais temporais com estruturas profundas como o hipotálamo devem ser responsáveis pelas manifestações vegetativas durante crises epilépticas temporais.<br>We describe a patient who had cardiac arrhythmia as epileptic manifestation. In a 34-year-old woman who had many episodes of loss of consciousness, the simultaneous ECG and video-EEG monitoring recorded bradycardia with a short episode of asystolia (4 seconds) and left temporal rhythmic teta activity on EEG. MRI showed a small mass lesion in the left parahippocampal gyrus. Alterations in cardiac rhythm have been reported in epileptic seizures and taquycardia is the most common finding associated with them; bradyarrhythmia during seizures was uncommon. Many interconnections among insular cortex, limbic system and hypothalamus, may be responsible for vegetative manifestations in temporal lobe epilepsy