Epilepsy and Seizure Disorders Flashcards
What is the definition of a seizure?
A transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain. The common mechanism involves a fundamental disruption of the balance between inhibitory and excitatory neuronal activity and the development of recurrent excitatory circuits.
What is ictal semiology, interictal, and postictal?
Behaviors exhibited during a seizure are ictal semiology.
Interictal refers to the period between seizures.
Postictal refers to the period of time after a seizure occurs, as in postictal confusion or drowsiness.
What are generalized seizures?
seizures that arise in and rapidly engage bilaterally distributed networks
What are focal seizures?
Localized seizures involve more limited networks, typically within one hemisphere
What does the term simple partial seizure refer to?
Seizures not associated with impairment of consciousness or awareness, may include focal sensory or motor experiences or autonomic components
What does the term complex partial seizure refer to?
Seizures with alteration of consciousness or awareness
What does the term secondary generalized refer to?
Seizures evolving to a bilateral convulsive seizure
Define epilepsy?
Recurrent, unprovoked seizures. In most cases, seizures are a symptom of an underlying pathological condition or process affecting brain function
What epilepsies and electroclinical syndromes have an onset in the neonatal period?
Benign neonatal seizures
Benign familial neonatal epilepsy
Ohtahara syndrome
Early myoclonic encephalopathy
What epilepsies and electroclinical syndromes have an onset in infancy?
Febrile seizures Benign infantile epilepsy Benign familial infantile epilepsy West syndrome Dravet syndrome Myoclonic epilepsy of infancy Myoclonic encephalopathy in non-progressive disorders Epilepsy of infancy with migrating seizures
What epilepsies and electroclinical syndromes have an onset in childhood?
Febrile seizures, Febrile seizures plus
Early onset childhood occipital epilepsy
Epilepsy with myoclonic atonic seizures (astatic)
Childhood absence epilepsy (CAE)
Benign epilepsy with centrotemporal spikes
Late-onset childhood occipital epilepsy
Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE)
Epilepsy with myoclonic absences
Lennox Gastaut syndrome
Epileptic encephalopathy with continuous spike and wave during sleep
Landau Kleffner syndrome
What epilepsies and electroclinical syndromes have an onset in adolescence/adulthood?
Juvenile absence epilepsy
Juvenile myoclonic epilepsy (JME)
Epilepsy with generalized tonic-clonic seizures alone
Autosomal dominant epilepsy with auditory features (ADEAF)
Other familiar temporal lobe epilepsies
What epilepsies and electroclinical syndromes have a variable age of onset?
Familial focal epilepsy with variable foci
Progressive myoclonus epilepsies
Reflex epilepsy
What is the most common site of underlying pathology in adults and adolescents who have seizures with alteration of consciousness?
The temporal lobe, particularly the hippocampus. Adults often have hippocampal sclerosis characterized by neuronal loss in the hippocampal formation, mostly CA1 and CA3 subfields. The remaining neurons may become part of an epileptogenic network marked by synaptic reorganization.
What is the most common underlying pathology in childhood onset epilepsy?
The majority have idiopathic or cryptogenic epilepsy. Remaining are presumed intrauterine insult (7%), documented perinatal stoke (2%), or identified malformations of cortical development (MCD; 3%), neurocutaneous syndromes, chromosomal or genetic defect, and neurodegenerative conditions are also implicated.
What are known risk factors for seizure recurrence?
prolonged febrile convulsions that may induce neurological injury, neoplasm, disorders of neuroblast migration (cortical dysplasia, heterotopias, TBI)
What factors determine severity of cognitive impairment, and which is the most significant predictor?
Seizure frequency is most significant. Other variables include type of epilepsy risk factor (tumor, CNS infection, trauma), younger age of seizure onset, number of AEDs
Risk factors for Temporal Lobe Epilepsy (TLE)
Associated with hx of febrile seizures as an infant or toddler, especially prolonged seizures or recurrent episodes of febrile seizures; hippocampal sclerosis (HS) associated with perinatal complications, hyposix injury, CNS infections
Age of epilepsy onset in those with febrile seizure hx
Trimodal with peaks at age 5, 15, and 26, greatest frequency is in second decade of life