Types of Seizures
Q: Are there different types of seizures?
Many varieties of epileptic seizures occur, and frequency and form of attacks vary greatly from person to person. With modern methods of treatment, however, most cases can be fully controlled. Because there are so many nuances in Epilepsy and so many different kinds of seizures, a specific classification system is being promoted by the International League Against Epilepsy. The International Classification of Epilepsy Seizures has been adopted by the medical community and is gradually replacing outdated seizure terminology including "grand mal" and "petit mal".
The new classification scheme describes two major types of seizures: "partial" and "generalized". It also divides each of these categories into subcategories including simple partial, complex-partial, absence, tonic-clonic, and other types.
Q: What is the difference between partial and general seizures?
The distinction between "partial" and "generalized" seizures is the most important feature of the new classifcation system. If the excessive electrical discharge in the brain is limited to one area, the seizure is partial. If the whole brain is involved, it is generalized. In all, there are over 30 different seizure types. Therefore, the new classification format subdivides the partial and generalized Epilepsies into a number of different categories.
Q: What are partial seizures?
Partial seizures (formerly known as focal seizures) with elementary symptomology are often referred to a simple partial. During this type of seizure the patient can experience a range of strange or unusual sensations including sudden, jerky movements of one body part, distortions in hearing or seeing, stomach discomfort, or a sudden sense of fear. Consciousness is not impaired. If another seizure type follows, these sensations may be referred to as an "aura".
Q: What are complex partial seizures?
Complex-partial seizures (formerly psychomotor or temporal lobe Epilepsy) are characterized by a complicated motor act involving impaired consciousness. During the seizure the patient appears dazed and confused. Purposeless behaviours such as random walking, mumbling, head turning, or pulling at clothing may be observed. Usually, these so-called "automatisms" cannot be recalled by the patient. In children this seizure may consist of staring or lip-smacking, and therefore may be confused with the absence seizure described below.
Q: What are absence (petit mal) seizures?
Generalized absence seizures (formerly petit mal) are characterized by 5 to 15 second lapses in consciousness. During this time the patient appears to be staring into space and the eyes may roll upwards. Absences are not preceded by an aura and activity can be resumed immediately afterwards. Typically, they occur in children and disappear by adolescence. They may, however, evolve into other seizure types, such as complex-partial or tonic-clonic. The occurrence of absences in adulthood are rare.
Q: What are tonic-clonic (grand mal) seizures?
The tonic-clonic (formerly grand mal) seizure is a generalized convulsion involving two phases. In the tonic phase, the individual loses consciousness and falls, and the body becomes rigid. In the clonic period, the body extremities jerk and twitch. After the seizure, consciousness is regained slowly. If the tonic-clonic seizure begins locally (with a partial seizure) it may be preceded by an "aura". These seizures are said to be secondarily generalized.
While the tonic-clonic seizure is the most visible, obvious type of Epilepsy, it is not the most common. Partial seizures are more frequently encountered and occur in 62% of all Epilepsy patients. Complex-partial seizures account for approximately 30% all cases.
Q: What are other types of seizures?
Benign rolandic epilepsy is an epileptic syndrome occurring in young children that is age limited (you stop having seizures in the teen years) . Salivation, twitching of the mouth or upper extremity on one side are typical manifestations. Seizures occur almost exclusively nocturnally.
Juvenile myoclonic epilepsy is an epilepsy characterized by onset in childhood or adolescence and is associated with extremity jerking or generalized tonic clonic seizures ('grand mal') within an hour or two of wakening from sleep. Seizures which may be precipitated by sleep deprivation, alcohol intake or coffee (strange) tend to occur in the morning.
Pleases contact your local Epilepsy association or clinic for additional information. Other seizure terms include: Atonic (Drop Attacks), Myclonic, Infantile Spasms, Nocturnal, Photosensitive, Visual, Musicogenic, Jacksonian, Sensory, Bilateral Myclonus, Atkinetic, Autonomic, Prolonged seizures, and Ictal State.
Q: What are "status" seizures?
Status epilepticus is the term used to describe recurrent seizures without recovery of consciousness between attacks. This is a medical emergency and can be life threatening, or cause brain damage. Immediate action to get the necessary medical care should be taken.
Q: What are pseudoseizures?
Psuedoseizures (or psychogenic seizures) are quite common and can occur in people who have, or do not have, Epilepsy. The attacks are triggered by a conscious or unconscious desire for more care and attention. The seizures start with rapid breathing, triggered by mental stress, anxiety, or pain. As the person breaths rapidly, they build up carbon dioxide in their body and change their chemistry. This can cause symptoms very much like Epileptic seizures: prickling in the face, hands, and feet, stiffening, trembling, etc. The appropriate treatment for pseudoseizures is to calm the person and start them breathing at a normal rate. Treatment should also involve investigating the mental and emotional factors that led to the psuedoseizure.
Q: How do you distinguish epileptic seizures from pseudoseizures?
Epileptic seizures and pseudoseizures are distinguishable both by their nature and symptoms, but the diagnosis can be difficult. Epileptic seizures are caused by a change in how the brain cells send electrical signals to each other, while pseudoseizures are triggered by a conscious or unconscious desire for more care and attention. Thus, measuring brain activity with an EEG and video telmetry is important for distinguishing epileptic and pseudoseizures. Also, pseudoseizures often lack the exhaustion, confusion, and nausea that is associated with epileptic seizures. Psychogenic seizures can occur in people who also experience epileptic seizures.
Q: Can seizures occur if a person does not have Epilepsy?
Epilepsy is a chronic condition of recurrent unprovoked seizures. Isolated seizures and provoked seizures (e.g., drug or alcohol induced) are not Epilepsy even though the events are real seizures. There are many types of non-epileptic seizures. Non-epileptic seizures differ from epileptic seizures in that there is usually no evidence of abnormal electrical activity in the brain after the seizure, and they do not occur repeatedly. Some of the more common causes of non-epileptic seizures are: low blood sugar, fainting, heart disease, stroke, migraine headaches, kinked blood vessels, narcolepsy, withdrawal, and extreme stress or anxiety.
Q: What are the seizures like?
The nature of the seizures varies depending upon the type of Epilepsy the individual has. Some seizures may be very noticeable while some may go completely unrecognized. With the most common types of seizures there is some loss of consciousness, but some seizures may only involve small movements of the body or strange feelings. The different seizures types have certain characteristics that accompany them.
Q: What does it feel like to have a seizure?
Epilepsy is a broad classification for a wide variety of seizures, so different people's seizures can be very different. Common feelings associated with seizures include uncertainty, fear, physical and mental exhaustion, confusion, and memory loss. Some types of seizures can produce visual and auditory phenomena, while others can involve a "blank" feeling. If a person is unconscious during a seizure there may be no feeling at all. Many people also experience an "aura" before the seizure itself.
Q: How long do the seizures last?
Depending on the type of seizure, they can last anywhere from a few seconds to several minutes. In rare cases, seizures can last many hours. For example, a tonic-clonic seizure typically lasts 1-7 minutes. Absence seizures may only last a few seconds, while complex partial seizures range from 30 seconds to 2-3 minutes. "Status Epilepticus" refers to prolonged seizures that can last for many hours, and this can be a serious medical condition. In most cases, however, seizures are fairly short and little first aid is required.
Q: Is there such a thing as a "minor" case of Epilepsy?
There are over 30 types of seizures, and some types are more severe than others. Long tonic-clonic convulsions, for example, can produce more physical and mental effects than shorter partial seizures. Some people may experience very frequent seizures (every few hours), while others can go for months or years without a seizure. Also, some seizures are easily controlled by drug therapies, while others may continue regardless of the medication that is tried.
