Neuronal ceroid lipofuscinoses Nita, Dragos A.; Mole, Sara E.; Minassian, Berge A.
Epileptic disorders,
September 2016, Letnik:
18, Številka:
s2
Journal Article
Recenzirano
The neuronal ceroid lipofuscinoses (NCL) are neurodegenerative conditions that associate cognitive decline, progressive cerebellar atrophy, retinopathy, and myoclonic epilepsy. NCL result from the ...excessive accumulation of neuronal and extraneuronal lipopigments, despite having diverse underlying biochemical aetiologies. Here we review the clinical presentation, pathophysiology and genetics of these conditions as well as the approach to diagnosis and management.
Abstract Objective Burst-suppression is an electroencephalographic pattern observed during coma. In individuals without known brain pathologies undergoing deep general anesthesia, somatosensory ...stimulation transiently increases the occurrence of bursts. We investigated the reactivity of burst-suppression in children with acquired brain injury. Methods Intensive care unit electroencephalographic monitoring recordings containing burst-suppression were obtained from 5 comatose children with acquired brain injury of various etiologies. Intermittent photic stimulation was performed at 1 Hz for 1 minute to assess reactivity. We quantified reactivity by measuring the change in the burst ratio (fraction of time in burst) following photic stimulation. Results Photic stimulation evoked bursts in all patients, resulting in a transient increase in the burst ratio, while the mean heart rate remained unchanged. The regression slope of the change in burst ratio, referred to as the standardized burst ratio reactivity, correlated with subjects’ Glasgow Coma Scale scores. Conclusions Reactivity of the burst-suppression pattern to photic stimulation occurs across diverse coma etiologies. Standardized burst ratio reactivity appears to reflect coma severity. Significance Measurement of burst ratio reactivity could represent a simple method to monitor coma severity in critically ill children.
The identification of a biomarker for sudden unexpected death in epilepsy (SUDEP) has the potential to save lives. Generalized convulsive seizures and postictal generalized suppression on ...electroencephalography (EEG) most often precede sudden unexpected death in epilepsy (SUDEP) and are potential biomarkers. We identify the EEG and seizure characteristics associated with postictal generalized EEG suppression in children with epilepsy.
Video EEGs were reviewed for seizure type, duration and semiology, and electrographic features. To identify predictors of postictal generalized EEG suppression, we identified 40 children with generalized convulsive seizures from a group of 399 patients who experienced an electroclinical seizure during video-EEG. Seventy-seven generalized convulsive seizures with and without postictal generalized EEG suppression were anayzed.
Age of seizure onset was older in 19 children with postictal generalized EEG suppression (mean 6.8 years old, 95% CI 4.7-8.9) than in 21 without postictal generalized EEG suppression (3.0 years old, 1.1-4.1, P = 0.041). Postictal generalized EEG suppression occurred significantly more often from sleep than awake (point of estimate 16.67; 95% CI 0.97-32.36, P < 0.038). Shorter duration of the clonic phase (−0.76; −1.338, −0.133, P = 0.018) was significantly associated with postictal generalized EEG suppression. Ictal symmetric tonic extension posturing significantly increased the odds of postictal generalized EEG suppression (42.94; 18.77, 67.12, P = 0.001). All 15 generalized convulsive seizures with a terminal burst-suppression pattern were followed by postictal generalized EEG suppression in contrast to 19 of 62 generalized convulsive seizures without burst-suppression (15.32, P < 0.001).
Ictal decerebrate-like symmetric tonic extension posturing with shorter clonic phase and a terminal burst-suppression pattern identify malignant generalized convulsive seizures, associated with postictal generalized EEG suppression and a potentially increased risk of sudden unexpected death in epilepsy.
The subtle mechanisms of post-traumatic epileptogenesis remain unknown, although the incidence of chronic epilepsy after penetrating cortical wounds is high. Here, we investigated whether the ...increased frequency of seizures occurring within 6 weeks following partial deafferentation of the suprasylvian gyrus in cats is accompanied with a change in the ratio between the number of excitatory and inhibitory neurons. Immuno-histochemical labeling of all neurons with neuronal-specific nuclear protein (NeuN) antibody, and of the GABAergic inhibitory neurons with either gamma-aminobutyric acid (GABA) or glutamic acid decarboxylase (GAD 65&67) antibodies, was performed on sections obtained from control and epileptic animals with chronically deafferented suprasylvian gyrus. Quantification of the labeled neurons was performed in control animals and at 2, 4, and 6 weeks following cortical deafferentation, in the suprasylvian and marginal gyri, both ipsi- and contra-lateral to the cortical trauma. In all epileptic animals, the neuronal loss was circumscribed to the deafferented suprasylvian gyrus. Inhibitory GABAergic neurons were particularly more sensitive to cortical deafferentation than excitatory ones, leading to a progressively increasing ratio between excitation and inhibition towards excitation, potentially explaining the increased propensity to seizures in chronic undercut cortex.
Acute cerebral cortical trauma often leads to paroxysmal activities that terminate in a few hours, but several months later, patients can develop epilepsy. The process occurring between the initial ...acute triggered seizures and the onset of spontaneous unprovoked seizures is termed epileptogenesis. Here the authors summarize recent morphological, electrophysiological, and computational studies demonstrating that partial cortical isolation increases the number and duration of silent states in the cortical network, boosting neuronal connectivity and network excitability. These changes develop progressively, and after several weeks their synergetic action leads to epilepsy.
•Comatose critically-ill children are at risk for seizures, often being electrographic-only, without accompanying clinical signs.•EEG features of the first 5 minutes of critical care EEG recordings ...differed among children who went on to develop acute seizures.•If validated in other cohorts, EEG features may be an effective seizure risk stratification tool for critically-ill children.
We aimed to test the hypothesis that computational features of the first several minutes of EEG recording can be used to estimate the risk for development of acute seizures in comatose critically-ill children.
In a prospective cohort of 118 comatose children, we computed features of the first five minutes of artifact-free EEG recording (spectral power, inter-regional synchronization and cross-frequency coupling) and tested if these features could help identify the 25 children who went on to develop acute symptomatic seizures during the subsequent 48 hours of cEEG monitoring.
Children who developed acute seizures demonstrated higher average spectral power, particularly in the theta frequency range, and distinct patterns of inter-regional connectivity, characterized by greater connectivity at delta and theta frequencies, but weaker connectivity at beta and low gamma frequencies. Subgroup analyses among the 97 children with the same baseline EEG background pattern (generalized slowing) yielded qualitatively and quantitatively similar results.
These computational features could be applied to baseline EEG recordings to identify critically-ill children at high risk for acute symptomatic seizures.
If confirmed in independent prospective cohorts, these features would merit incorporation into a decision support system in order to optimize diagnostic and therapeutic management of seizures among comatose children.
Anti–glutamic acid decarboxylase directed antibodies are a rare cause of autoimmune limbic encephalitis that is relatively resistant to immunotherapy. Here we report a 15-year-old boy with ...nonparaneoplastic, anti–glutamic acid decarboxylase limbic encephalitis presenting with subacute headache, memory disturbance, psychiatric symptoms, and seizures. At onset, his memory disturbance manifested as transient global amnesia-like episodes. Clinical remission was achieved with rituximab, intravenous immunoglobulin, and corticosteroids.
Highlights • Power of post-spike slow wave increased in all areas from interictal to preictal period. • Power of post-spike slow wave within the seizure onset zone (SOZ) was significantly higher than ...that outside SOZ during preictal period. • Post-spike slow wave with high power became confined to SOZ toward seizure onset.
Highlights • The spatial concordance between the fast and slow EEG components differs between ictal activities during epileptic spasms and interictal epileptiform discharges. • The slow EEG ...components of ictal activities of epileptic spasms are discordant with the areas of the fast components. • Generators of the slow EEG components of interictal epileptiform discharges overlap with the areas of the preceding fast EEG components.
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