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ABSENCE SEIZURES INCLUDING ATYPICAL ABSENCE SEIZURES
This vote and comments section applies to those
who suffers from ABSENCE Seizures.
*Special Note - ATYPICAL ABSENCE APPLIES TO THIS
POLL AS WELL *
Here are some partial quotes:
ABSENCE SEIZURES - from eMed
ABSENCE SEIZURES - Epilepsy Foundation
ABSENCE SEIZURES by Epilepsy.com
ATYPICAL ABSENCE SEIZURES by Epilepsy.com
Feel free to bring about any discussion as
you wish, and you may click on the links above
to learn more in details.
This vote and comments section applies to those
who suffers from ABSENCE Seizures.
*Special Note - ATYPICAL ABSENCE APPLIES TO THIS
POLL AS WELL *
Here are some partial quotes:
ABSENCE SEIZURES - from eMed
Absence seizures are a type of generalized seizures. They were first described Poupart in 1705, and later by Tissot in 1770, who used the term petit access. In 1824, Calmeil used the term absence. In 1935, Gibbs, Davis, and Lennox described the association of impaired consciousness and 3-Hz spike-and-slow-wave complexes on electroencephalograms (EEGs).
Absence seizures occur in both idiopathic and symptomatic generalized epilepsies. Among the idiopathic, or primary, generalized epilepsies (ie, with age-related onset), absence seizures are seen in childhood absence epilepsy (CAE, or pyknolepsy), juvenile absence epilepsy (JAE), and juvenile myoclonic epilepsy (JME, or impulsive petit mal seizures). The seizures in these conditions are called typical absence seizures and usually associated with 3-Hz spike-and-slow-wave complexes on EEG. In CAE, seizures are frequent and brief, lasting just a few seconds (pyknoleptic). Some children can have hundreds of such seizures per day. In other epilepsies, particularly those with an older age of onset, the seizures can last several seconds to minutes and may occur only a few times a day (called nonpyknoleptic or spanioleptic absence seizures). Myoclonic and tonic-clonic seizures may also be present, especially in syndromes with an older age of onset. In these syndromes, the discharge frequency may be faster than 3 Hz.
In the symptomatic generalized epilepsies, absence seizures are often associated with slow spike-wave complexes of 1.5-2.5 Hz; these are also called sharp-and-slow-wave complexes. These seizures are termed atypical absence seizures.
Pathophysiology: The etiology of idiopathic epilepsies with age-related onset is genetic. About 15-40% of patients with these epilepsies have a family history of epilepsy; concordance in monozygotic twins is 75%. Family members may have other forms of idiopathic or genetic epilepsy (eg, febrile convulsions, generalized tonic-clonic [GTC] seizures).
Several animal models demonstrate the genetic basis for absence seizures. A strain of Wistar rat, ie, genetic absence epilepsy rats from Strasbourg (GAERS), is a polygenetic model in which all animals have clinical seizures consisting of a behavioral arrest with twitching of facial muscles. This is associated with bilateral synchronous spike-wave discharges. Several single-gene loci in mice, when mutated, result in generalized spike-wave epilepsy. The tottering (chromosome 8 ), lethargic (chromosome 2), stargazer (chromosome 15), mocha (chromosome 10), and ducky (chromosome 9) loci all have generalized 6-per-second spike-wave EEG paroxysms that are associated with clinical seizures consisting of behavioral arrest. All types respond to ethosuximide (ETX), but the underlying cellular mechanisms for the generation of the discharges are not identical.
Several mutations of genes which encode protein subunits in various ion channels have been found in patients and family members with idiopathic epilepsies. Some forms of JME and absence epilepsy have been shown to result from mutations in Ca++ channels.
In symptomatic generalized epilepsies, absence seizures are due to a wide variety of causes that, at an early stage of neural development, result in diffuse or multifocal brain damage. The causes of secondary generalized epilepsies and the other seizure types that accompany them, and their management, are not discussed in this article.
The pathophysiology of absence seizures is not fully understood. In 1947, Jasper and Droogleever-Fortuyn electrically stimulated nuclei in the thalami of cats at 3 Hz and produced bilaterally synchronous spike-and-wave discharges on EEG. In 1953, bilaterally synchronous spike-and-wave discharges were recorded by using depth electrodes placed in the thalamus of a child with absence seizures.
In 1977, Gloor demonstrated that the bilaterally synchronous 3-Hz spike-wave discharges in the feline penicillin model of absence seizures were generated in the cortex. This led to the corticoreticular theory of primarily generalized seizures.
Abnormal oscillatory rhythms are believed to develop in thalamocortical pathways. This involves GABA-B–mediated inhibition alternating with glutamate-mediated excitation. The cellular mechanism is believed to involve T-type calcium currents. T channels of the GABAergic reticular thalamic nucleus neurons appear to play a major role in the spike-wave discharges of the GABAergic thalamic neurons. GABA-B inhibition appears to be altered in absence seizures, and potentiation of GABA-B inhibition with tiagabine (Gabitril), vigabatrin (Sabril), and possibly gabapentin (Neurontin) results in exacerbation of absence seizures. Enhanced burst firing in selected corticothalamic networks may increase GABAB receptor activation in the thalamus, leading to generalized spike-wave activity.
Frequency:
* In the US: The incidence is 1.9-8 cases per 100,000 population.
Mortality/Morbidity:
* No deaths result directly from absence seizures. Accidents from driving or operating dangerous machinery during absence may result in death. In children with absence seizures due to secondary generalized epilepsies, death is related to the underlying disease.
* The morbidity from typical absence seizures is related to the frequency and duration of the seizures, as well as to the patient's activities; effective treatment ameliorates these factors. Educational problems and behavioral problems are sequelae of unrecognized, frequent seizures.
Race: No racial predilection is known.
Sex:
* Absence seizures are generally believed to be more common in females and in males, with some studies showing a 2:1 female-to-male ratio. Other studies have shown no difference between the sexes.
* Absence epilepsy with myoclonus has a male predominance.
Age: The generalized idiopathic epilepsies have age-related onset. Onset of absence seizures in children with symptomatic generalized epilepsies depends on the underlying disorder. While many of these disorders may have their onset at an early (prenatal, perinatal, or postnatal) age, absence seizures do not appear until later in childhood.
An example is the Lennox-Gastaut syndrome. The cause may be a genetic disorder or a perinatal insult, but the absence seizures do not present until age 1-8 years.
* CAE onset is at age 4-8 years, with peak onset at age 6-7 years.
* JAE onset is at age 7-14 years, with peak onset at age 10-12 years. Onset of JAE with myoclonus averages about age 7 years.
* JME has a more varied age of onset (8-26 y), but 79% of patients have an onset at age 12-18 years. Because the absence and myoclonic seizures are brief, they often go unrecognized, and many patients do not present until they experience a tonic-clonic seizure.
ABSENCE SEIZURES - Epilepsy Foundation
Absence Seizures (also called Petit Mal)
'Although manifestations of their seizures are usually subtle, children with absence seizures need prompt and effective treatment because their seizures can interfere with learning.'
What to Do:
No first aid is necessary, but if this is the first observation of an absence seizure, medical evaluation is recommended.
Absence seizures (also called petit mal seizures) are lapses of awareness, sometimes with staring, that begin and end abruptly, lasting only a few seconds. There is no warning and no after-effect.
More common in children than in adults, absence seizures almost always start between ages 4 and 12 years, and rarely do they begin after age 20. Absence seizures are characterized by a brief impairment of consciousness, which usually lasts no more than a few seconds. The child, whether sitting or standing, simply stares vacantly; neither speaking nor apparently hearing what is said. Then, as abruptly as it began, the impairment lifts and the child continues with his or her previous activity. However, a brief segment of unawareness has been imposed in the stream of activity or thought. Automatisms may occur in prolonged absence seizures. Absence seizures are frequently so brief that they escape detection, even if the child is experiencing 50 to 100 attacks daily. They may occur for several months or even years before a child is sent for a medical evaluation.
Absence Seizure Characteristics:
* No aura
* Abrupt onset
* Brief duration
* Prompt recovery
Some absence seizures are accompanied by brief myoclonic jerking of the eyelids or facial muscles, or by variable loss of muscle tone. More prolonged attacks may be accompanied by automatisms, which may lead them to be confused with complex partial seizures. However, complex partial seizures last longer, may be preceded by an aura, and are usually marked by some type of confusion following the seizure.
Absence seizures may occur only occasionally or more than 100 times a day. Most children with typical absence seizures are otherwise normal. Although manifestations of their seizures are usually subtle, these children need prompt and effective treatment because absence seizures can interfere with learning. About half the children also have infrequent generalized tonic-clonic seizures. The electroencephalographic (EEG) pattern of diffuse spike-wave is closely correlated with absence seizures.
ABSENCE SEIZURES by Epilepsy.com
Absence seizures are brief episodes of staring. (Although the name looks like a regular English word, your neurologist may pronounce it ab-SAWNTZ.) Another name for them is petit mal (PET-ee mahl). During the seizure, awareness and responsiveness are impaired. People who have them usually don't realize when they've had one. There is no warning before a seizure, and the person is completely alert immediately afterward.
Simple absence seizures are just stares. Many absence seizures are considered complex absence seizures, which means that they include a change in muscle activity. The most common movements are eye blinks. Other movements include slight tasting movements of the mouth, hand movements such as rubbing the fingers together, and contraction or relaxation of the muscles. Complex absence seizures are often more than 10 seconds long.
Who gets them?
Absence seizures usually begin between ages 4 and 14. The children who get them usually have normal development and intelligence.
What's the outlook?
In nearly 70% of cases, absence seizures stop by age 18. Children who develop absence seizures before age 9 are much more likely to outgrow them than children whose absence seizures start after age 10.
Children with absence seizures do have higher rates of behavioral, educational, and social problems.
What else could it be?
Absence seizures can resemble some complex partial seizures or episodes of daydreaming:
- How frequent are the episodes? Daydreaming: Not frequent. Seizures: Complex partial: Rarely more than several times per day or week.
Absence: Could be many times per day.- In what situations do they occur? Daydreaming: Boring situation. Seizures: Any time, including during physical activity; often with hyperventilation (deep or rapid breathing.)
- Do they begin abruptly? Daydreaming:No. Seizures: Usually yes. Some complex partial seizures begin slowly with a warning.
- Can they be interrupted? Yes. No.
- How long do they last? Daydreaming: Until something interesting happens. Seizures: Complex partial: Up to several minutes
Absence: Rarely more than 15-20 seconds- Does the person do anything during the episode? Daydreaming
robably just stares. Seizures: Complex partial: Automatisms are common.
Absence: Just stares.- What is the person like immediately after the episode? Daydreaming:Alert. Seizures: Complex partial: Confused.
Absence: Alert.
ATYPICAL ABSENCE SEIZURES by Epilepsy.com
Atypical (a-TIP-i-kul) means unusual or not typical. The person will stare (as they would in any absence seizure) but often is somewhat responsive. Eye blinking or slight jerking movements of the lips may occur. This behavior can be hard to distinguish from the person's usual behavior, especially in those with cognitive impairment. Unlike other absence seizures, these seizures usually cannot be produced by rapid breathing.
Who gets them?
They generally begin before age 6. Most of the children affected have below-average intelligence and other types of seizures that are difficult to control. Many have Lennox-Gastaut syndrome.
What's the outlook?
Atypical absence seizures usually continue into adulthood.
What else could it be?
Sometimes ordinary behavior for these children will look like an atypical absence seizure. Daydreaming and inattentiveness can mimic these seizures.
How is the diagnosis made?
The diagnosis can be difficult if the behavior during seizures is similar to the child's usual behavior. The EEG (electroencephalogram), which records brain waves, will be used, but most children with these seizures have patterns on their EEG when they're not having a seizure that are similar to the seizure pattern.
Feel free to bring about any discussion as
you wish, and you may click on the links above
to learn more in details.
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