|Synonyms||Epileptic fit, seizure, fit, convulsions|
|Generalized 3 Hz spike and wave discharges in EEG|
|Specialty||Neurology, emergency medicine|
|Duration||Typically < 2 minutes|
|Causes||Provoked: Low blood sugar, alcohol withdrawal, low blood sodium, fever, brain infection, concussion |
Unprovoked: Unknown, brain injury, brain tumor, previous stroke
|Diagnostic method||Based on symptoms, blood tests, medical imaging, electroencephalography|
|Differential diagnosis||Syncope, nonepileptic psychogenic event, tremor, migraine, transient ischemic attack|
|Treatment||Less than 5 min: Place person on their side, remove nearby dangerous objects |
More than 5 min: Treat as per status epilepticus
|Frequency||~10% of people (at one point in time)|
A seizure, technically known as an epileptic seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain.Outward effects vary from uncontrolled shaking movements involving much of the body with loss of consciousness (tonic-clonic seizure), to shaking movements involving only part of the body with variable levels of consciousness (focal seizure), to a subtle momentary loss of awareness (absence seizure). Most of the time these episodes last less than 2 minutes and it takes some time to return to normal. Loss of bladder control may occur.
Neural oscillations, or brainwaves, are rhythmic or repetitive patterns of neural activity in the central nervous system. Neural tissue can generate oscillatory activity in many ways, driven either by mechanisms within individual neurons or by interactions between neurons. In individual neurons, oscillations can appear either as oscillations in membrane potential or as rhythmic patterns of action potentials, which then produce oscillatory activation of post-synaptic neurons. At the level of neural ensembles, synchronized activity of large numbers of neurons can give rise to macroscopic oscillations, which can be observed in an electroencephalogram. Oscillatory activity in groups of neurons generally arises from feedback connections between the neurons that result in the synchronization of their firing patterns. The interaction between neurons can give rise to oscillations at a different frequency than the firing frequency of individual neurons. A well-known example of macroscopic neural oscillations is alpha activity.
The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. The brain is located in the head, usually close to the sensory organs for senses such as vision. The brain is the most complex organ in a vertebrate's body. In a human, the cerebral cortex contains approximately 14–16 billion neurons, and the estimated number of neurons in the cerebellum is 55–70 billion. Each neuron is connected by synapses to several thousand other neurons. These neurons communicate with one another by means of long protoplasmic fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body targeting specific recipient cells.
Focal seizures are seizures which affect initially only one hemisphere of the brain. The brain is divided into two hemispheres, each consisting of four lobes – the frontal, temporal, parietal and occipital lobes. A focal seizure is generated in and affects just one part of the brain – a whole hemisphere or part of a lobe. Symptoms will vary according to where the seizure occurs. In the frontal lobe symptoms may include a wave-like sensation in the head; in the temporal lobe, a feeling of déjà vu; in the parietal lobe, a numbness or tingling; and in the occipital lobe, visual disturbance or hallucination.
Seizures may be provoked and unprovoked.Provoked seizures are due to a temporary event such as low blood sugar, alcohol withdrawal, low blood sodium, fever, brain infection, or concussion. Unprovoked seizures occur without a known or fixable cause such that ongoing seizures are likely. Unprovoked seizures may be triggered by stress or sleep deprivation. Diseases of the brain, where there has been at least one seizure and a long term risk of further seizures, are collectively known as epilepsy. Conditions that look like epileptic seizures but are not include fainting, nonepileptic psychogenic event, and tremor.
Fever, also known as pyrexia and febrile response, is defined as having a temperature above the normal range due to an increase in the body's temperature set point. There is not a single agreed-upon upper limit for normal temperature with sources using values between 37.5 and 38.3 °C. The increase in set point triggers increased muscle contractions and causes a feeling of cold. This results in greater heat production and efforts to conserve heat. When the set point temperature returns to normal, a person feels hot, becomes flushed, and may begin to sweat. Rarely a fever may trigger a febrile seizure. This is more common in young children. Fevers do not typically go higher than 41 to 42 °C.
Concussion, also known as mild traumatic brain injury (mTBI), is typically defined as a head injury that temporarily affects brain functioning. Symptoms may include headaches, trouble with thinking, memory or concentration, nausea, blurry vision, sleep disturbances or mood changes. Some symptoms may begin immediately, while others may appear days after the injury. Fewer than 10% of sports-related concussions among children are associated with loss of consciousness. It is not unusual for symptoms to last up to four weeks.
In psychology, stress is a feeling of strain and pressure. Stress is a type of psychological pain. Small amounts of stress may be desired, beneficial, and even healthy. Positive stress helps improve athletic performance. It also plays a factor in motivation, adaptation, and reaction to the environment. Excessive amounts of stress, however, may lead to bodily harm. Stress can increase the risk of strokes, heart attacks, ulcers, and mental illnesses such as depression.
A seizure that lasts for more than a brief period of time is a medical emergency.Any seizure lasting longer than 5 minutes should be treated as status epilepticus. A first seizure generally does not require long term treatment with anti-seizure medications unless a specific problem is found on electroencephalogram (EEG) or brain imaging. Typically it is safe to complete the work-up following a single seizure as an outpatient. In many, with what appears to be a first seizure, other minor seizures have previously occurred.
A medical emergency is an acute injury or illness that poses an immediate risk to a person's life or long-term health. These emergencies may require assistance from another person, who should ideally be suitably qualified to do so, although some of these emergencies such as cardiovascular (heart), respiratory, and gastrointestinal cannot be dealt with by the victim themselves. Dependent on the severity of the emergency, and the quality of any treatment given, it may require the involvement of multiple levels of care, from first aiders through Emergency Medical Technicians, paramedics, emergency physicians and anaesthesiologists.
Status epilepticus (SE) is a single epileptic seizure lasting more than five minutes or two or more seizures within a five-minute period without the person returning to normal between them. Previous definitions used a 30-minute time limit. The seizures can be of the tonic–clonic type, with a regular pattern of contraction and extension of the arms and legs, or of types that do not involve contractions, such as absence seizures or complex partial seizures. Status epilepticus is a life-threatening medical emergency particularly if treatment is delayed.
Up to 10% of people have at least one epileptic seizure.Provoked seizures occur in about 3.5 per 10,000 people a year while unprovoked seizures occur in about 4.2 per 10,000 people a year. After one seizure, the chance of experiencing a second is about 50%. Epilepsy affects about 1% of the population at any given time with about 4% of the population affected at some point in time. Nearly 80% of those with epilepsy live in developing countries. Many places require people to stop driving until they have not had a seizure for a specific period of time.
A developing country is a country with a less developed industrial base and a low Human Development Index (HDI) relative to other countries. However, this definition is not universally agreed upon. There is also no clear agreement on which countries fit this category. A nation's GDP per capita compared with other nations can also be a reference point.
The signs and symptoms of seizures vary depending on the type.The most common type of seizure is convulsive (60%). Two-thirds of these begin as focal seizures and become generalized while one third begin as generalized seizures. The remaining 40% of seizures are non-convulsive, an example of which is absence seizure.
Absence seizures are one of several kinds of generalized seizures. These seizures are sometimes referred to as petit mal seizures. Absence seizures are characterized by a brief loss and return of consciousness, generally not followed by a period of lethargy.
Focal seizures are often preceded by certain experiences, known as an aura.These may include sensory, visual, psychic, autonomic, olfactory or motor phenomena.
An aura is a perceptual disturbance experienced by some with migraines or seizures. The aura stage precedes a seizure in epilepsy but can happen at any stage of a migraine. It often manifests as the perception of a strange light, an unpleasant smell, or confusing thoughts or experiences. Some people experience aura without a subsequent migraine or seizure. Auras vary by individual experience; some people experience smells, lights, or hallucinations. Less known symptoms of the eye include disturbances, where the eyes roll in the back of the head caused by photosensitivity. A sufferer of this type of aura may experience tearfulness of the eyes and uncontrollable sensations of light followed by reduced symptoms after approximately 20 minutes; it is the rarest type of aura.
In a complex partial seizure a person may appear confused or dazed and can not respond to questions or direction. Focal seizure may become generalized.
Jerking activity may start in a specific muscle group and spread to surrounding muscle groups—known as a Jacksonian march .Unusual activities that are not consciously created may occur. These are known as automatisms and include simple activities like smacking of the lips or more complex activities such as attempts to pick something up.
There are six main types of generalized seizures: tonic-clonic, tonic, clonic, myoclonic, absence, and atonic seizures.They all involve a loss of consciousness and typically happen without warning.
A seizure can last from a few seconds to more than five minutes, at which point it is known as status epilepticus. seconds in duration.Most tonic-clonic seizures last less than two or three minutes. Absence seizures are usually around 10
After the active portion of a seizure, there is typically a period of confusion called the postictal period before a normal level of consciousness returns.This usually lasts 3 to 15 minutes but may last for hours. Other common symptoms include: feeling tired, headache, difficulty speaking, and abnormal behavior. Psychosis after a seizure is relatively common, occurring in between 6 and 10% of people. Often people do not remember what occurred during this time.
Seizures have a number of causes. Of those who have a seizure, about 25% have epilepsy.A number of conditions are associated with seizures but are not epilepsy including: most febrile seizures and those that occur around an acute infection, stroke, or toxicity. These seizures are known as "acute symptomatic" or "provoked" seizures and are part of the seizure-related disorders. In many the cause is unknown.
Different causes of seizures are common in certain age groups.
Dehydration can trigger epileptic seizures if it is severe enough.A number of disorders including: low blood sugar, low blood sodium, hyperosmolar nonketotic hyperglycemia, high blood sodium, low blood calcium and high blood urea levels may cause seizures. As may hepatic encephalopathy and the genetic disorder porphyria.
Both medication and drug overdoses can result in seizures,as may certain medication and drug withdrawal. Common drugs involved include: antidepressants, antipsychotics, cocaine, insulin, and the local anaesthetic lidocaine. Difficulties with withdrawal seizures commonly occurs after prolonged alcohol or sedative use, a condition known as delirium tremens.
Stress can induce seizures in people with epilepsy, and is a risk factor for developing epilepsy. Severity, duration, and time at which stress occurs during development all contribute to frequency and susceptibility to developing epilepsy. It is one of the most frequently self-reported triggers in patients with epilepsy.
Stress exposure results in hormone release that mediates its effects in the brain. These hormones act on both excitatory and inhibitory neural synapses, resulting in hyper-excitability of neurons in the brain. The hippocampus is known to be a region that is highly sensitive to stress and prone to seizures. This is where mediators of stress interact with their target receptors to produce effects.
Seizures may occur as a result of high blood pressure, known as hypertensive encephalopathy, or in pregnancy as eclampsia when accompanied by either seizures or a decreased level of consciousness. 42 °C (107.6 °F).Very high body temperatures may also be a cause. Typically this requires a temperature greater than
Electroconvulsive therapy (ECT) deliberately sets out to induce a seizure for the treatment of major depression.
Normally brain electrical activity is non synchronous.In epileptic seizures, due to problems within the brain, a group of neurons begin firing in an abnormal, excessive, and synchronized manner. This results in a wave of depolarization known as a paroxysmal depolarizing shift.
Normally after an excitatory neuron fires it becomes more resistant to firing for a period of time.This is due in part from the effect of inhibitory neurons, electrical changes within the excitatory neuron, and the negative effects of adenosine. In epilepsy the resistance of excitatory neurons to fire during this period is decreased. This may occur due to changes in ion channels or inhibitory neurons not functioning properly. Forty-one ion-channel genes and over 1,600 ion-channel mutations have been implicated in the development of epileptic seizure. These ion channel mutations tend to confer a depolarized resting state to neurons resulting in pathological hyper-excitability. This long-lasting depolarization in individual neurons is due to an influx of Ca2+ from outside of the cell and leads to extended opening of Na+ channels and repetitive action potentials. The following hyperpolarization is facilitated by γ-aminobutyric acid (GABA) receptors or potassium (K+) channels, depending on the type of cell. Equally important in epileptic neuronal hyper-excitability, is the reduction in the activity of inhibitory GABAergic neurons, an effect known as disinhibition. Disinhibition may result from inhibitory neuron loss, dysregulation of axonal sprouting from the inhibitory neurons in regions of neuronal damage, or abnormal GABAergic signaling within the inhibitory neuron. Neuronal hyper-excitability results in a specific area from which seizures may develop, known as a "seizure focus". Following an injury to the brain, another mechanism of epilepsy may be the up regulation of excitatory circuits or down regulation of inhibitory circuits. These secondary epilepsies occur through processes known as epileptogenesis. Failure of the blood–brain barrier may also be a causal mechanism. While blood-brain barrier disruption alone does appear to cause epileptogenesis, it has been correlated to increased seizure activity. Furthermore, it has been implicated in chronic epileptic conditions through experiments inducing barrier permeability with chemical compounds. Disruption may lead to fluid leaking out of the blood vessels into the area between cells and driving epileptic seizures. Preliminary findings of blood proteins in the brain after a seizure support this theory.
Focal seizures begin in one hemisphere of the brain while generalized seizures begin in both hemispheres.Some types of seizures may change brain structure, while others appear to have little effect. Gliosis, neuronal loss, and atrophy of specific areas of the brain are linked to epilepsy but it is unclear if epilepsy causes these changes or if these changes result in epilepsy.
Seizure activity may be propagated through the brain's endogenous electrical fields.Proposed mechanisms that may cause the spread and recruitment of neurons include an increase in K+ from outside the cell, and increase of Ca2+ in the presynaptic terminals. These mechanisms blunt hyperpolarization and depolarizes nearby neurons, as well as increasing neurotransmitter release.
Seizures may be divided into provoked and unprovoked.Provoked seizures may also be known as "acute symptomatic seizures" or "reactive seizures". Uprovoked seizures may also be known as "reflex seizures". Depending on the presumed cause blood tests and lumbar puncture may be useful. Hypoglycemia may cause seizures and should be ruled out. An electroencephalogram and brain imaging with CT scan or MRI scan is recommended in the work-up of seizures not associated with a fever.
Seizure types are organized by whether the source of the seizure is localized (focal seizures) or distributed (generalized seizures) within the brain.Generalized seizures are divided according to the effect on the body and include tonic-clonic (grand mal), absence (petit mal), myoclonic, clonic, tonic, and atonic seizures. Some seizures such as epileptic spasms are of an unknown type.
Focal seizures (previously called partial seizures) are divided into simple partial or complex partial seizure. Current practice no longer recommends this, and instead prefers to describe what occurs during a seizure.
Most people are in a postictal state (drowsy or confused) following a seizure. They may show signs of other injuries. A bite mark on the side of the tongue helps confirm a seizure when present, but only a third of people who have had a seizure have such a bite.When present in people thought to have had a seizure, this physical sign tentatively increases the likelihood that a seizure was the cause.
An electroencephalography is only recommended in those who likely had an epileptic seizure and may help determine the type of seizure or syndrome present. In children it is typically only needed after a second seizure. It cannot be used to rule out the diagnosis and may be falsely positive in those without the disease. In certain situations it may be useful to prefer the EEG while sleeping or sleep deprived.
Diagnostic imaging by CT scan and MRI is recommended after a first non-febrile seizure to detect structural problems inside the brain.MRI is generally a better imaging test except when intracranial bleeding is suspected. Imaging may be done at a later point in time in those who return to their normal selves while in the emergency room. If a person has a previous diagnosis of epilepsy with previous imaging repeat imaging is not usually needed with subsequent seizures.
In adults, testing electrolytes, blood glucose and calcium levels is important to rule these out as causes, as is an electrocardiogram.A lumbar puncture may be useful to diagnose a central nervous system infection but is not routinely needed. Routine antiseizure medical levels in the blood are not required in adults or children. In children additional tests may be required.
A high blood prolactin level within the first 20 minutes following a seizure may be useful to confirm an epileptic seizure as opposed to psychogenic non-epileptic seizure.Serum prolactin level is less useful for detecting partial seizures. If it is normal an epileptic seizure is still possible and a serum prolactin does not separate epileptic seizures from syncope. It is not recommended as a routine part of diagnosis epilepsy.
Differentiating an epileptic seizure from other conditions such as syncope can be difficult.Other possible conditions that can mimic a seizure include: decerebrate posturing, psychogenic seizures, tetanus, dystonia, migraine headaches, and strychnine poisoning. In addition, 5% of people with a positive tilt table test may have seizure-like activity that seems due to cerebral hypoxia. Convulsions may occur due to psychological reasons and this is known as a psychogenic non-epileptic seizure. Non-epileptic seizures may also occur due to a number of other reasons.
A number of measures have been attempted to prevent seizures in those at risk. Following traumatic brain injury anticonvulsants decrease the risk of early seizures but not late seizures. [ needs update ]
In those with a history of febrile seizures, medications (both antipyretics and anticonvulsants) have not been found effective for prevention. Some, in fact, may cause harm.
There is no clear evidence that antiepileptic drugs are effective or not effective at preventing seizures following a craniotomy, [ needs update ] following subdural hematoma, after a stroke, or after subarachnoid haemorrhage, for both people who have had a previous seizure, and those who have not.
Potentially sharp or dangerous objects should be moved from the area around a person experiencing a seizure, so that the individual is not hurt. After the seizure if the person is not fully conscious and alert, they should be placed in the recovery position. A seizure longer than five minutes, or two or more seizures occurring within the time of five minutes is a medical emergency known as status epilepticus.Contrary to a common misconception, bystanders should not attempt to force objects into the mouth of the person suffering a seizure, as doing so may cause injury to the teeth and gums.
Treatments of a person that is actively seizing follows a progression from initial response, through first line, second line, and third line treatments.The initial response involves ensuring the person is protected from potential harms (such as nearby objects) and managing their airway, breathing, and circulation. Airway management should include placing the person on their side, known as the recovery position, to prevent them from choking. If they are unable to breathe because something is blocking their airway, they may require treatments to open their airway.
The first line medication for an actively seizing person is a benzodiazepine, with most guidelines recommending lorazepam.Diazepam and midazolam are alternatives. This may be repeated if there is no effect after 10 minutes. If there is no effect after two doses, barbiturates or propofol may be used. Benzodiazepines given by a non-intravenous route appear better than those given by intravenous, as the intravenous takes longer to have an effect.
Second-line therapy for adults is phenytoin or fosphenytoin and phenobarbital for children. [ page needed ] Third-line medications include phenytoin for children and phenobarbital for adults. [ page needed ]
Ongoing anti-epileptic medications are not typically recommended after a first seizure except in those with structural lesions in the brain.They are generally recommended after a second one has occurred. Approximately 70% of people can obtain full control with continuous use of medication. Typically one type of anticonvulsant is preferred. Following a first seizure, while immediate treatment with an anti-seizure drug lowers the probability of seizure recurrence up to five years it does not change the risk of death and there are potential side effects.
In seizures related to toxins, up to two doses of benzodiazepines should be used.If this is not effective pyridoxine is recommended. Phenytoin should generally not be used.
There is a lack of evidence for preventative anti-epileptic medications in the management of seizures related to intracranial venous thrombosis.
Helmets may be used to provide protection to the head during a seizure. Some claim that seizure response dogs, a form of service dog, can predict seizures. [ needs update ]Evidence for this, however, is poor. At present there is not enough evidence to support the use of cannabis for the management of seizures, although this is an ongoing area of research. There is tentative evidence that a ketogenic diet may help in those who have epilepsy and is reasonable in those who do not improve following typical treatments.
Following a first seizure, the risk of more seizures in the next two years is 40%–50%.The greatest predictors of more seizures are problems either on the electroencephalogram or on imaging of the brain. In adults, after 6 months of being seizure-free after a first seizure, the risk of a subsequent seizure in the next year is less than 20% regardless of treatment. Up to 7% of seizures that present to the emergency department (ER) are in status epilepticus. In those with a status epilepticus, mortality is between 10% and 40%. Those who have a seizure that is provoked (occurring close in time to an acute brain event or toxic exposure) have a low risk of re-occurrence, but have a higher risk of death compared to those with epilepsy.
Approximately 8-10% of people will experience an epileptic seizure during their lifetime.In adults, the risk of seizure recurrence within the five years following a new-onset seizure is 35%; the risk rises to 75% in persons who have had a second seizure. In children, the risk of seizure recurrence within the five years following a single unprovoked seizure is about 50%; the risk rises to about 80% after two unprovoked seizures. In the United States in 2011, seizures resulted in an estimated 1.6 million emergency department visits; approximately 400,000 of these visits were for new-onset seizures. The exact incidence of epileptic seizures in low-income and middle-income countries is unknown, however it probably exceeds that in high-income countries. This may be due to increased risks of traffic accidents, birth injuries, and malaria and other parasitic infections.
Epileptic seizures were first described in an Akkadian text from 2000 B.C.Early reports of epilepsy often saw seizures and convulsions as the work of “evil spirits”. The perception of epilepsy, however, began to change in the time of Ancient Greek medicine. The term “epilepsy” itself is a Greek word, which is derived from the verb “epilambanein”, meaning “to seize, possess, or afflict”. Although the Ancient Greeks referred to epilepsy as the “sacred disease”, this perception of epilepsy as a “spiritual” disease was challenged by Hippocrates in his work “On The Sacred Disease” , who proposed that the source of epilepsy was from natural causes rather than supernatural ones.
Early surgical treatment of epilepsy was primitive in Ancient Greek, Roman and Egyptian medicine. Another advancement was that of the development by the Montreal procedure by Canadian neurosurgeon Wilder Penfield, which involved use of electrical stimulation among conscious patients to more accurately identify and resect the epileptic areas in the brain.The 19th century saw the rise of targeted surgery for the treatment of epileptic seizures, beginning in 1886 with localized resections performed by Sir Victor Horsley, a neurosurgeon in London.
Seizures result in direct economic costs of about one billion dollars in the United States. billion USD or 0.5% of the GDP. They make up about 1% of emergency department visits (2% for emergency departments for children) in the United States.Epilepsy results in economic costs in Europe of around 15.5 billion Euros in 2004. In India, epilepsy is estimated to result in costs of 1.7
Many areas of the world require a minimum of six months from the last seizure before people can drive a vehicle.
Scientific work into the prediction of epileptic seizures began in the 1970s. Several techniques and methods have been proposed, but evidence regarding their usefulness is still lacking.
Two promising areas include gene therapy,and seizure detection and seizure prediction.
Gene therapy for epilepsy consists of employing vectors to deliver pieces of genetic material to areas of the brain involved in seizure onset.
Seizure prediction is a special case of seizure detection in which the developed systems is able to issue a warning before the clinical onset of the epileptic seizure.
Epilepsy is a group of neurological disorders characterized by epileptic seizures. Epileptic seizures are episodes that can vary from brief and nearly undetectable periods to long periods of vigorous shaking. These episodes can result in physical injuries, including occasionally broken bones. In epilepsy, seizures tend to recur and, as a rule, have no immediate underlying cause. Isolated seizures that are provoked by a specific cause such as poisoning are not deemed to represent epilepsy. People with epilepsy may be treated differently in various areas of the world and experience varying degrees of social stigma due to their condition.
Anticonvulsants are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of bipolar disorder and borderline personality disorder, since many seem to act as mood stabilizers, and for the treatment of neuropathic pain. Anticonvulsants suppress the excessive rapid firing of neurons during seizures. Anticonvulsants also prevent the spread of the seizure within the brain.
Topiramate is a broad-spectrum anticonvulsant (antiepilepsy) drug. In late 2012, topiramate was approved by the United States Food and Drug Administration (FDA) in combination with phentermine for weight loss. The drug had previously been used off-label for this purpose. Topiramate was originally produced by Ortho-McNeil Neurologics and Noramco, Inc., both divisions of the Johnson & Johnson Corporation. This medication was discovered in 1979 by Bruce E. Maryanoff and Joseph F. Gardocki during their research work at McNeil Pharmaceuticals.
Lamotrigine, sold as the brand name Lamictal among others, is an anticonvulsant medication used to treat epilepsy and bipolar disorder. For epilepsy, this includes focal seizures, tonic-clonic seizures, and seizures in Lennox-Gastaut syndrome. In bipolar disorder, it is used to treat acute episodes of depression, rapid cycling in bipolar type II, and prevent recurrence in bipolar type I.
Levetiracetam, marketed under the trade name Keppra among others, is a medication used to treat epilepsy. It is used for partial onset, myoclonic, or tonic-clonic seizures. It is taken by mouth as an immediate release or extended release formulation or by injection into a vein.
Epilepsia partialis continua is a rare type of brain disorder in which a patient experiences recurrent motor epileptic seizures that are focal, and recur every few seconds or minutes for extended periods.
Clobazam is a benzodiazepine class medication that has been marketed as an anxiolytic since 1975 and an anticonvulsant since 1984.
Stiripentol is an anticonvulsant drug used in the treatment of epilepsy. It is approved for the treatment of Dravet syndrome, an epilepsy syndrome. It is unrelated to other anticonvulsants and belongs to the group of aromatic allylic alcohols.
Temporal lobe epilepsy (TLE) is a chronic disorder of the nervous system characterized by recurrent, unprovoked focal seizures that originate in the temporal lobe of the brain and last about one or two minutes. TLE is the most common form of epilepsy with focal seizures. A focal seizure in the temporal lobe may spread to other areas in the brain when it may become a focal to bilateral seizure.
Sudden unexpected death in epilepsy (SUDEP) is a fatal complication of epilepsy. It is defined as the sudden and unexpected, non-traumatic and non-drowning death of a person with epilepsy, without a toxicological or anatomical cause of death detected during the post-mortem examination.
Racine stages are a categorization of epileptic seizures proposed by Ronald J. Racine in 1972. Prior to Racine's research in epilepsy, a quantifiable means to describe seizure intensities and their causes was not readily available. Racine's work allowed for epilepsy to be understood on a level previously thought impossible.
A generalized tonic–clonic seizure is a type of generalized seizure that produces bilateral, convulsive tonic and clonic muscle contractions. Tonic–clonic seizures are the seizure type most commonly associated with epilepsy and seizures in general and the most common seizure associated with metabolic imbalances. It is a misconception that they are the sole type of seizure, however, as they are the main seizure type in only ~10% of those with epilepsy.
Post-traumatic epilepsy (PTE) is a form of epilepsy that results from brain damage caused by physical trauma to the brain. A person with PTE suffers repeated post-traumatic seizures more than a week after the initial injury. PTE is estimated to constitute 5% of all cases of epilepsy and over 20% of cases of symptomatic epilepsy.
Post-traumatic seizures (PTS) are seizures that result from traumatic brain injury (TBI), brain damage caused by physical trauma. PTS may be a risk factor for post-traumatic epilepsy (PTE), but a person who has a seizure or seizures due to traumatic brain injury does not necessarily have PTE, which is a form of epilepsy, a chronic condition in which seizures occur repeatedly. However, "PTS" and "PTE" may be used interchangeably in medical literature.
Epileptogenesis is the gradual process by which a normal brain develops epilepsy. Epilepsy is a chronic condition in which seizures occur. These changes to the brain occasionally cause neurons to fire in a hyper-synchronous manner, known as a seizure.
Benign Rolandic epilepsy or benign childhood epilepsy with centrotemporal spikes (BCECTS) is the most common epilepsy syndrome in childhood. Most children will outgrow the syndrome, hence the label benign. The seizures, sometimes referred to as sylvian seizures, start around the central sulcus of the brain.
There are many causes of seizures. The factors that lead to a seizure are often complex and it may not be possible to determine what causes a particular seizure, what causes it to happen at a particular time, or how often seizures occur.
Febrile infection-related epilepsy syndrome (FIRES) is a form of epilepsy that affects children three to fifteen years old. A healthy child that may have been ill in the last few days or with a lingering fever goes into a state of continuous seizures. The seizures are resistant to seizure medications and treatments, though barbiturates may be administered. Medical diagnostic tests may initially return no clear diagnosis and may not detect any obvious swelling on the brain. The syndrome is very rare: it may only affect 1 in 1,000,000 children.
A neonatal seizure is a seizure in a baby younger than 4 weeks old. Seizures are abnormally excessive or synchronous neuronal activity in the brain. They are the most frequent neurological problem in the nursery, and often require evaluation and treatment in a neonatal intensive care unit. Seizures in the neonatal population can be categorized into acute symptomatic seizures and genetic or structural causes. Diagnosis relies on identification of the cause of the seizure, and verification of actual seizure activity by measuring of electrical activity with electroencephalography (EEG). Treatment depends on the cause of the seizure, but often includes pharmacologic treatment with anti-epileptic drugs.
electric fields can be solely responsible for spike propagation at ... This phenomenon could be important to explain the slow propagation of epileptic activity and other normal propagations at similar speeds.
|Look up epileptic seizure in Wiktionary, the free dictionary.|