ABPN Epilepsy key terms

The process by which a previously normal brain develops a persistent predisposition to generate seizures, often after injury, and involving network reorganization, inflammation, and altered excitability.

The moment-to-moment transition from interictal state to a seizure, driven by failure of inhibitory restraint and recruitment of hypersynchronous neural activity.

A prolonged intracellular depolarization with superimposed action potentials seen in epileptic neurons, representing a cellular correlate of the interictal spike.

An experimental phenomenon in which repeated subthreshold electrical stimulation progressively lowers seizure threshold until a full motor seizure is elicited, modeling plasticity in epileptogenesis.

Synaptic inhibition mediated by gamma-aminobutyric acid acting mainly on GABA-A chloride channels and GABA-B receptors, which restrains neuronal firing and is a major drug target.

A mechanism shared by phenytoin, carbamazepine, lamotrigine, and lacosamide in which channels in the inactivated state are stabilized, limiting high-frequency repetitive firing.

Sudden unexpected death in epilepsy, defined as a nontraumatic, non-drowning death in a person with epilepsy that is not explained by a documented cause, often occurring during or after a nocturnal convulsion.

A seizure arising within one hemisphere with preserved awareness throughout, previously termed a simple partial seizure; motor, sensory, autonomic, or psychic symptoms may occur.

A focal-onset seizure during which awareness is impaired at some point, often accompanied by automatisms; previously called a complex partial seizure.

A subjective sensation that may precede a focal seizure with impaired awareness, representing the early focal aware phase of the seizure; its character can help localize the onset zone.

The systematic description of the clinical signs and symptoms of seizures, used with EEG and imaging to infer the site of seizure onset and spread.

Sustained involuntary muscle contraction during a seizure, often a version or posturing of a limb; asymmetric dystonic posturing frequently lateralizes onset to the contralateral hemisphere.

Transient focal weakness following a seizure, typically resolving over hours, that localizes to the hemisphere of seizure onset and can mimic stroke.

A generalized EEG pattern of a spike followed by a slow wave, often at about 3 Hz in absence epilepsy, reflecting thalamocortical hypersynchrony.

A chaotic, high-amplitude, disorganized interictal EEG pattern with multifocal spikes and slow waves, classically associated with infantile spasms and West syndrome.

The most common focal epilepsy syndrome, often with hippocampal sclerosis, characterized by auras, impaired awareness, automatisms, and interictal temporal spikes on EEG.

A neuropathologic finding of neuronal loss and gliosis in the hippocampus, commonly seen with mesial temporal lobe epilepsy and detectable on MRI as atrophy and signal change.

A prolonged seizure or series of seizures without full recovery between them; operationally, continuous seizure activity lasting five minutes or more requires emergent treatment.

A class of drugs enhancing GABA-A receptor chloride currents, used as first-line therapy for acute seizures and status epilepticus, with tolerance and dependence as risks.

Measurement of serum antiseizure medication concentrations to guide dosing, most useful for drugs with narrow therapeutic ranges and saturable or unpredictable kinetics.

Upregulation of hepatic cytochrome P450 enzymes by drugs such as carbamazepine or phenytoin, accelerating metabolism of coadministered medications and reducing their efficacy.

A broad-spectrum antiseizure medication effective for generalized and focal epilepsies, with risks of hepatotoxicity, pancreatitis, and teratogenicity, especially neural tube defects.

A resective epilepsy surgery removing the anterior temporal lobe and mesial structures, offering high seizure-freedom rates in appropriately selected mesial temporal lobe epilepsy.

A palliative neuromodulation therapy using an implanted device to deliver intermittent electrical stimulation to the left vagus nerve, reducing seizure frequency in refractory focal epilepsy.

An implanted closed-loop device that detects epileptiform activity and delivers targeted electrical stimulation to reduce seizures in drug-resistant focal epilepsy.

A palliative disconnection procedure dividing the corpus callosum, used mainly for disabling drop attacks in refractory generalized or multifocal epilepsy.

A functional hemisphere disconnection surgery used for severe unilateral hemispheric disease such as Rasmussen encephalitis or Sturge-Weber syndrome, aiming to stop seizures and improve function.

A progressive unilateral inflammatory disorder causing intractable focal seizures, hemiparesis, and cognitive decline, often treated with hemispherotomy or immunotherapy.

An epileptic encephalopathy of infancy with clusters of flexor or extensor spasms, hypsarrhythmia on EEG, and developmental regression, treated urgently with hormonal therapy or vigabatrin.

A condition in which abundant epileptiform activity itself contributes to progressive cognitive and behavioral impairment beyond what the underlying pathology alone would cause.

A severe childhood epileptic encephalopathy with multiple seizure types including tonic and atonic seizures, cognitive impairment, and a slow spike-wave EEG pattern.

Management of epilepsy during gestation, balancing seizure control against teratogenic risk; preconception planning and avoiding valproate when possible are emphasized.

The evaluation process identifying patients with drug-resistant epilepsy likely to benefit from resection or disconnection, using semiology, EEG, MRI, and often video-EEG monitoring.

Nighttime monitoring or co-sleeping strategies intended to detect and respond to seizures, a counseling measure sometimes recommended to reduce SUDEP risk in high-risk patients.

A seizure with tonic stiffening followed by rhythmic clonic jerking, typically generalized from onset in primary generalized epilepsy or secondarily generalized in focal epilepsy.

The period of altered consciousness, confusion, fatigue, or focal deficits immediately following a seizure, useful for distinguishing epileptic from nonepileptic events.

A paroxysmal event resembling a seizure that is not caused by abnormal electrical brain activity and is often associated with psychological distress, diagnosed by video-EEG.

Continuous synchronized recording of clinical behavior and EEG, typically in an epilepsy monitoring unit, used to classify seizures and capture events for diagnosis and presurgical evaluation.