Seizure Types (2017 UPDATED classifications)

Seizure Classification

**(UPDATE: “In 2017, the ILAE released a new classification of seizure types, largely based upon the existing classification formulated in 1981. Primary differences include specific listing of certain new focal seizure types that may previously only have been in the generalized category, use of awareness as a surrogate for consciousness, emphasis on classifying focal seizures by the first clinical manifestation (except for altered awareness), a few new generalized seizure types, ability to classify some seizures when onset is unknown, and renaming of certain terms to improve clarity of meaning. Seizure types are organized according to whether the source of the seizure within the brain is localized or distributed. Here is a list and description of some of the most common types.” >>>> READ MORE ABOUT THEM HERE >>>>

Abdominal (Autonomic) Epilepsy: Abdominal Epilepsy, sometimes referred to as autonomic seizures, is a very rare form of seizure which presents with the acute onset of symptoms seemingly related to the gastrointestinal (GI) system. Sudden abdominal pain and other symptoms can occur which are generally first thought to be related to abdominal disease such as irritable bowel syndrome or gastroenteritis.

However, in a small set of patients it has been shown that these symptoms can occur along with seizure activity in the brain, demonstrated by electroencephalogram (EEG), and may respond to treatment with anti epileptic medications. Panayiotopoulos syndrome is a benign age-related focal seizure disorder occurring in early and mid-childhood. It is characterized by seizures, often prolonged, with predominantly autonomic symptoms, and by an EEG (electroencephalogram) that shows shifting and/or multiple foci, often with occipital predominance.

Absence Seizures: Absence seizures are brief episodes of staring or daydreaming. 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. During this seizure the person may blink their eyes rapidly, pick at clothing, smack their lips, or swallow frequently. These seizures typically last anywhere from 3 to 20 seconds and can occur up to several hundred times a day. This type of seizure usually begins in childhood between the ages of 4 and 12.

Atonic Seizures: Muscle “tone” is the muscle’s normal tension. “Atonic” (a-TON-ik) means “without tone,” so in an atonic seizure, an epileptic seizure characterized by sudden loss of muscle tone; may cause the head to drop suddenly, objects to fall from the hands, or the legs to lose strength, with falling and potential injury; usually not associated with loss of consciousness. Close muscles suddenly lose strength. The eyelids may droop, the head may nod, and the person may drop things and often falls to the ground. These seizures are also called “drop attacks” or “drop seizures.” The person usually remains conscious. Another name for this type of seizure is “akinetic” (a-kin-ET-ik), which means “without movement.”

Atypical Absence Seizures: 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.

Aura: A warning before a seizure; a simple partial seizure occurring within seconds before a complex partial or secondarily generalized tonic-clonic seizure, or it may occur alone; also a warning before a migraine headache.

Autonomic Seizures (Simple Partial): These common seizures may include strange or unpleasant sensations in the stomach, chest, or head.

Catamenial Epilepsy: Refers to seizure exacerbation in relation to the menstrual cycle. Traditionally, the term has been used to refer to seizure exacerbation at the time of menstruation.

Childhood Absence Epilepsy: The seizures of childhood absence epilepsy (CAE) are usually staring spells during which the child is not aware or responsive.

Clonic Seizures: Clonic seizures consist of rhythmic jerking movements of the arms and legs, sometimes on both sides of the body.

Complex Febrile: Age, neurological status before the illness, and fever are the same as for simple febrile seizure. This seizure is either focal or prolonged (i.e., >15 min), or multiple seizures occur in close succession.

Complex Partial: These seizures affect a larger portion of the brain than the simple partial seizures, but the seizure activity is still limited to part of the brain. Complex partials can occur in any part of the brain, but they mainly occur in temporal and frontal lobe epilepsies. A person having a complex partial will not be aware of what is going on during the seizure and will have a brief postictal phase following the seizure. During a complex partial seizure the person may wander around aimlessly as if in a trance, stare vacantly, pick at clothing, and/or make chewing motions. They may try to talk but speech will be garbled. These seizures typically last from 30 seconds to 1 or 2 minutes.

Eclampsia: Convulsions are the other most common feature of this syndrome. Convulsions are the most common neurologic manifestation in Eclampsia because the occurrence of convulsions confirms the diagnosis of Eclampsia. Convulsions are usually generalized tonic-clonic in nature. Usually a brief single seizure occurs. Multiple seizures can also occur; however, status Epilepticus is rare. Partial seizures or complex partial seizures can also occur. The seizures can occur prepartum, intrapartum, or postpartum. If the seizure occurs postpartum, it usually occurs within the first 24 hours after delivery; however, late postpartum eclamptic convulsions are by no means rare and have been reported as late as 23 days postpartum.

Emotional Seizures: A type of simple partial seizure which manifests as exaggerated emotions without cause, most commonly fear, though joy, rage, anger or sadness may also occur.

Febrile Seizures (3 months to 5 years old): A febrile seizure occurs when a child contracts an illness such as an ear infection, cold, or chickenpox accompanied by a high fever. Febrile seizures are the most common type of seizure seen in children. Two to five percent of children have a febrile seizure at some point during their childhood. Why some children have seizures with fevers is not known, but several risk factors have been identified.

Focal Seizures (Partial Seizures): Focal seizures (also called partial seizures) occur in a limited area of the brain. The seizures may sometimes turn into generalized seizures, which affect the entire brain. This is called secondary generalization.

Frontal Lobe Epilepsy: Frontal Lobe Epilepsy are seizures that originate in the front of the brain. The epilepsy symptoms can vary depending on what part of the brain is involved. Frontal lobe seizures may produce unusual symptoms that can appear to be related to a psychiatric problem or a sleep disorder. Frontal Lobe Seizures often occur during sleep and may feature bicycle pedaling motions and pelvic thrusting. Some people scream profanities or laugh during Frontal Lobe Seizures.

Gelastic Seizures: A Gelastic Seizure is a rare type of epilepsy which is also known as Gelastic Epilepsy. Gelastic seizure is defined as sudden occurrence of emotions in the form of a laugh or a cry. The name gelastic epilepsy comes from Greek word ‘gelos’ which means laughter. Time of seizure is generally 5 to 60 seconds. Percentage of occurrence is slightly higher in male than female. Previously it is considered that gelastic seizures are originated in the temporal lobes but further study described that it is associated with hypothalamic hamartomas. It is affected to any age group but mostly before three or four years of age. In most of the cases gelastic seizures is followed by tonic-clonic seizures and atonic seizures.

Generalized-Onset Seizures: Generalized-onset seizures have an onset recorded simultaneously in both cerebral hemispheres. Generalized-onset seizures are classified into 6 major categories: (1) absence seizures, (2) tonic seizures, (3) clonic seizures, (4) myoclonic seizures, (5) primary generalized tonic-clonic seizures, and (6) atonic seizures.

Infantile Spasms(West Syndrome): Infantile spasms may begin up to age 2, but most commonly begin between the 4 and 6 months, with about 90 percent beginning in the first year. The causes are widely variable and in some cases are unknown. However, the most common causes are tuberous sclerosis and perinatal asphyxia (lack of oxygen). Parents sometimes attribute the cause to pertussis vaccination, a connection that has yet to be proven. Since the peak in onset of spasms occurs at the same age range that the vaccination is given, it is likely that the concurrent timing is the only link.

Juvenile Absence Epilepsy: All children with juvenile absence epilepsy (JAE) have absence seizures but usually they are limited to a few episodes per day. Tonic-clonic (grand mal) seizures are usually the symptom that brings the patient to the doctor.

Juvenile Myoclonic Epilepsy: People with JME have myoclonic seizures (quick little jerks of the arms, shoulder, or occasionally the legs), usually in the early morning, soon after awakening. The myoclonic jerks sometimes are followed by a tonic-clonic seizure. Absence seizures also may occur.

Multifocal Seizures: Whilst most seizures can be neatly split into partial and generalized, there exists some that don’t fit. For example: the seizure may be generalized only within one hemisphere. Alternatively there may be many focal points (multifocal seizures) that are distributed in a symmetrical or asymmetrical pattern.

Myoclonic Seizures: Brief, shock-like jerks of a muscle or a group of muscles. “Myo” means muscle and “clonus” (KLOH-nus) means rapidly alternating contraction and relaxation “jerking or twitching” of a muscle.

Neonatal Onset Seizures (first two months of life): Neonatal Onset Seizures happen more frequently in the newly born than at any other stage in life. They occur in preterm neonates (babies born earlier than 40 weeks) somewhat more frequently than in full-term babies. Babies who have seizures in the first few days after delivery tend to have more severe outcomes than those whose seizures begin later in the neonatal period.

Nocturnal Seizures: Nocturnal seizures are usually tonic-clonic. They might occur just after a person has fallen asleep, just before waking, during daytime sleep, or while in a state of drowsiness. People who experience nocturnal seizures may find it difficult to wake up or to stay awake.

Occipital Lobe Seizure: Occipital Lobe Seizures arise from the occipital lobe of the brain, which sits at the back of the brain, just below the parietal lobe and just behind the temporal lobe. The occipital lobe is the main center of the visual system. Occipital lobe epilepsy accounts for about 5-10% of all epilepsy. This kind of epilepsy can be either idiopathic (of unknown, presumed genetic, cause) or symptomatic (associated with a known or suspected underlying lesion). Benign occipital epilepsies usually begin in childhood and are discussed elsewhere.

Partial Seizures: An electrical disturbance which limits itself to a certain part of the brain such as the temporal or frontal lobes.

Photosensitive Epilepsy: Seizures occur when an individual is exposed to visual stimuli, usually flashes of light of a particular frequency. In other reflex epilepsies, seizures may be provoked by auditory, olfactory, or vestibular stimuli.

Post Traumatic Epilepsy: Post traumatic epilepsy (PTE) refers to a recurrent seizure disorder, the cause of which is believed to be injury to the brain. This injury can be a result of head trauma or a sequel to an operation on the brain. The term PTE must be differentiated from the term post traumatic seizure (PTS), which signifies any seizure that occurs as a sequel to brain injury. The seizures are usually partial (focal) or generalized tonic-clonic. Often, both types coexist. Most early PTS are partial seizures, whereas most late PTS, especially when part of PTE, are generalized and either primary or secondary.

Post traumatic Seizure: Any seizure that occurs as a sequel to brain injury. If the seizures occur within 24 hours of the injury, they are called immediate PTS. A PTS that occurs within 1 week of injury are termed early PTS, and a seizure that occurs more than 1 week after injury is termed late PTS. About 20% of people who have 1 late PTS never have any more. The seizures are usually partial (focal) or generalized tonic-clonic. Often, both types coexist. Most early PTS are partial seizures, whereas most late PTS, especially when part of PTE (Post traumatic Epilepsy), are generalized and either primary or secondary.

Progressive Myoclonic Epilepsies: Progressive myoclonic epilepsies feature a combination of myoclonic and tonic-clonic seizures. Unsteadiness, muscle rigidity, and mental deterioration are often also present.

Pseudo seizures (Psychogenic Seizures): Events that look like seizures but are not due to epilepsy are called “non epileptic seizures.” A common type is described as psychogenic (si-ko-JEN-ik), which means beginning in the mind.

Reflex Epilepsies: Reflex Seizures (Epilepsy) are a group of seizures in which certain stimulus can bring upon a seizure. It can be as somethings simple within the environment or more complex as active brain functioning in reading, writing, arithmetic or even thinking about certain topics.

Secondarily Generalized Seizures: Seizures of this kind start as a partial seizure, that is, they start in one limited area of the brain. The forms they take vary as much as other partial seizures.

Simple Partial: These seizures can be further broken down into different classes depending on the symptoms. A person can have motor, sensory, autonomic, and/or psychic symptoms. Examples of motor symptoms could be (but are not limited to): abnormal jerking of fingers, hands, or arms. This can be unilateral (one side) or bilateral (both sides). Examples of sensory symptoms could be (but are not limited to): a strange sense of taste or smell, a feeling of numbness, and/or seeing flashing lights. Examples of autonomic symptoms could be (but are not limited to): strange sensation in the stomach, nausea, stomach pain, and/or vomiting. Examples of psychic symptoms could be (but are not limited to): a sense of deja vu, memory impairment, difficulty speaking, and/or feelings of intense emotions.

A person having a simple partial seizure will often remain aware of what is going on during the seizure but may not be able to respond. Simple partial seizures typically last from 30 seconds to 1 or 2 minutes. During this time the person may be walking around fumbling at clothing, smacking their lips, bobbing their head, or even laughing/crying.

Subtle Seizures: Examples include chewing, pedaling or ocular movements. These seizures may look like absence seizures, lasting for a few seconds. The brain activity may be even more subtle and very difficult for teachers, parents or health care staff to spot.

Temporal Lobe Epilepsy: The temporal lobes, one on each side of the head, just above the ears, are the sites of one of the most common forms of epilepsy. Complex partial seizures with automatisms (unconscious actions), such as lip smacking or rubbing the hands together, are the most common seizures in temporal lobe epilepsy. Seventy-five percent of patients also experience simple partial seizures (Auras) which may include such features as: a mixture of thoughts, emotions, and feelings that are hard to describe; sudden emergence of old memories or feelings of strangeness in familiar surroundings; hallucinations of voices, music, smells, or tastes, and feelings of unusual fear or joy.

While partial seizures dominate, approximately half the people with temporal lobe epilepsy have generalized tonic-clonic seizures as well. The seizures characteristic of temporal lobe epilepsy often begin in the deeper parts of the temporal lobe (part of the limbic system) which control emotions and memory. Memory problems may develop over time in people with this syndrome.

Tonic Seizures: Muscle “tone” is the muscle’s normal tension at rest. In a “tonic” seizure, the tone is greatly increased and the body, arms, or legs make sudden stiffening movements. Consciousness is usually preserved.

Tonic-clonic Seizures: This type is what most people think of when they hear the word “seizure.” An older term for them is “grand mal”. A person having this seizure will first stiffen (tonic phase) and then go into rhythmic jerking of all extremities (clonic phase.) Some people may only experience the tonic phase or the clonic phase.

A person having a tonic clonic seizure will appear to have slowed their breathing or even stopped breathing and their lips may even turn blue. Breathing should start again after the clonic phase. The person may even be incontinent of bladder and bowel. After the person comes around he/she may be very tired and confused and will not remember what happened.

Visual Reflex Seizures: Visual reflex seizures induced by complex stimuli may be triggered by patterned and flashing displays that are now ubiquitous. The seizures may be clinically generalized, but unilateral and bilateral myoclonic attacks also may be triggered.

Withdrawal Seizures: This type of seizure is seen when certain medications, such as barbiturates and benzodiazepines, are stopped abruptly. Withdrawal seizures are common when a person with alcoholism is trying to quit drinking.



Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s