From WebMD:
“Types of Epilepsy
Epilepsy is the occurrence of sporadic electrical storms in the brain commonly called seizures. These storms cause behavioral manifestations (such as staring) and/or involuntary movements (such as grand mal seizures).
There are several types of epilepsy, each with different causes, symptoms, and treatments.
When making a diagnosis of epilepsy, your doctor may use one of the following terms: idiopathic, cryptogenic, symptomatic, generalized, focal, or partial. Idiopathic means there is no apparent cause. Cryptogenic means there is a likely cause, but it has not been identified. Symptomatic means that a cause has been identified. Generalized means that the seizures are involving the whole brain at once. Focal or partial means that the seizure starts from one area of the brain.
Major Types of Epilepsy
Types of Epilepsy Generalized Epilepsy Partial Epilepsy
Idiopathic (genetic causes) – Childhood absence epilepsy
– Juvenile myoclonic epilepsy
– Epilepsy with grand-mal seizures on awakening Others – Benign focal epilepsy of childhood
Symptomatic (cause unknown) or cryptogenic (cause unknown) – West syndrome
– Lennox-Gastaut syndrome
– Others
– Temporal lobe epilepsy
– Frontal lobe epilepsy Others
Idiopathic Generalized Epilepsy
In idiopathic generalized epilepsy, there is often, but not always, a family history of epilepsy. Idiopathic generalized epilepsy tends to appear during childhood or adolescence, although it may not be diagnosed until adulthood. In this type of epilepsy, no nervous system (brain or spinal cord) abnormalities other than the seizures have been identified as of yet. The brain is structurally normal on a brain magnetic resonance imaging (MRI) scan.
People with idiopathic generalized epilepsy have normal intelligence and the results of the neurological exam and MRI are usually normal. The results of the electroencephalogram (EEG — a test which measures electrical impulses in the brain) may show epileptic discharges affecting the entire brain (so called generalized discharges).
The types of seizures affecting patients with idiopathic generalized epilepsy may include:
Myoclonic seizures (sudden and very short duration jerking of the extremities)
Absence seizures (staring spells)
Generalized tonic-clonic seizures (grand mal seizures)
Idiopathic generalized epilepsy is usually treated with medications. Some forms of this condition that may be outgrown, as is the case with childhood absence epilepsy and a large number of patients with juvenile myoclonic epilepsy.
Idiopathic Partial Epilepsy
Idiopathic partial epilepsy begins in childhood (between ages 5 and 8) and may have a family history. Also known as benign focal epilepsy of childhood (BFEC), this is considered one of the mildest types of epilepsy. It is almost always outgrown by puberty and is never diagnosed in adults.
Seizures tend to occur during sleep and are most often simple partial motor seizures that involve the face and secondarily generalized (grand mal) seizures. This type of epilepsy is usually diagnosed with an EEG.
Symptomatic Generalized Epilepsy
Symptomatic generalized epilepsy is caused by widespread brain damage. Injury during birth is the most common cause of symptomatic generalized epilepsy. In addition to seizures, these patients often have other neurological problems, such as mental retardation or cerebral palsy. Specific, inherited brain diseases, such as adrenoleukodystrophy (ADL) or brain infections (such as meningitis and encephalitis) can also cause symptomatic generalized epilepsy. When the cause of symptomatic general epilepsy cannot be identified, the disorder may be referred to as cryptogenic epilepsy. These epilepsies include different subtypes — the most commonly known type is the Lennox-Gastaut syndrome.
Multiple types of seizures (generalized tonic-clonic, tonic, myoclonic, tonic, atonic, and absence seizures) are common in these patients and can be difficult to control. Learn more about these seizure types.
Symptomatic Partial Epilepsy
Symptomatic partial (or focal) epilepsy is the most common type of epilepsy that begins in adulthood, but it does occur frequently in children. This type of epilepsy is caused by a localized abnormality of the brain, which can result from strokes, tumors, trauma, congenital (present at birth) brain abnormality, scarring or “sclerosis” of brain tissue, cysts, or infections.
Sometimes these brain abnormalities can be seen on MRI scans, but often they cannot be identified, despite repeated attempts, because they are microscopic.
This type of epilepsy may be successfully treated with surgery that is aimed to remove the abnormal brain area without compromising the function of the rest of the brain. Epilepsy surgery is very successful in a large number of epilepsy patients who failed multiple anticonvulsant medications (at least two or three drugs) and who have identifiable lesions. These patients undergo a presurgical comprehensive epilepsy evaluation in dedicated and specialized epilepsy centers.
Epilepsy Seizure Types and Symptoms
Based on the type of behavior and brain activity, seizures are divided into two broad categories: generalized and partial (also called local or focal). Classifying the type of seizure helps doctors diagnose whether or not a patient has epilepsy.
Generalized seizures are produced by electrical impulses from throughout the entire brain, whereas partial seizures are produced (at least initially) by electrical impulses in a relatively small part of the brain. The part of the brain generating the seizures is sometimes called the focus. The most common types of seizures are listed below:
Generalized Seizures
(Produced by the entire brain) Symptoms
1. “Grand Mal” or Generalized tonic-clonic Unconsciousness, convulsions, muscle rigidity
2. Absence Brief loss of consciousness
3. Myoclonic Sporadic (isolated), jerking movements
4. Clonic Repetitive, jerking movements
5. Tonic Muscle stiffness, rigidity
6. Atonic Loss of muscle tone
Generalized Seizures
There are six types of generalized seizures. The most common and dramatic, and therefore the most well known, is the generalized convulsion, also called the grand-mal seizure. In this type of seizure, the patient loses consciousness and usually collapses. The loss of consciousness is followed by generalized body stiffening (called the “tonic” phase of the seizure) for 30 to 60 seconds, then by violent jerking (the “clonic” phase) for 30 to 60 seconds, after which the patient goes into a deep sleep (the “postictal” or after-seizure phase). During grand-mal seizures, injuries and accidents may occur, such as tongue biting and urinary incontinence.
Absence seizures cause a short loss of consciousness (just a few seconds) with few or no symptoms. The patient, most often a child, typically interrupts an activity and stares blankly. These seizures begin and end abruptly and may occur several times a day. Patients are usually not aware that they are having a seizure, except that they may be aware of “losing time.”
Myoclonic seizures consist of sporadic jerks, usually on both sides of the body. Patients sometimes describe the jerks as brief electrical shocks. When violent, these seizures may result in dropping or involuntarily throwing objects.
Clonic seizures are repetitive, rhythmic jerks that involve both sides of the body at the same time.
Tonic seizures are characterized by stiffening of the muscles.
Atonic seizures consist of a sudden and general loss of muscle tone, particularly in the arms and legs, which often results in a fall.
Partial Seizures
(Produced by a small area of the brain) Symptoms
1. Simple (awareness is retained)
a. Simple Motor
b. Simple Sensory
c. Simple Psychological a. Jerking, muscle rigidity, spasms, head-turning
b. Unusual sensations affecting either the vision, hearing, smell taste, or touch
c. Memory or emotional disturbances
2. Complex
(Impairment of awareness) Automatisms such as lip smacking, chewing, fidgeting, walking and other repetitive, involuntary but coordinated movements
3. Partial seizure with secondary generalization Symptoms that are initially associated with a preservation of consciousness that then evolves into a loss of consciousness and convulsions.
Partial Seizures
Partial seizures are divided into simple, complex and those that evolve into secondary generalized seizures. The difference between simple and complex seizures is that during simple partial seizures, patients retain awareness; during complex partial seizures, they lose awareness.
Simple partial seizures are further subdivided into four categories according to the nature of their symptoms: motor, autonomic, sensory, or psychological. Motor symptoms include movements such as jerking and stiffening. Sensory symptoms caused by seizures involve unusual sensations affecting any of the five senses (vision, hearing, smell, taste, or touch). When simple partial seizures cause sensory symptoms only (and not motor symptoms), they are called “auras.”
Autonomic symptoms affect the autonomic nervous system, which is the group of nerves that control the functions of our organs, like the heart, stomach, bladder, intestines. Therefore autonomic symptoms are things like racing heart beat, stomach upset, diarrhea, loss of bladder control. The only common autonomic symptom is a peculiar sensation in the stomach that is experienced by some patients with a type of epilepsy called temporal lobe epilepsy. Simple partial seizures with psychological symptoms are characterized by various experiences involving memory (the sensation of deja-vu), emotions (such as fear or pleasure), or other complex psychological phenomena.
Complex partial seizures, by definition, include impairment of awareness. Patients seem to be “out of touch,” “out of it,” or “staring into space” during these seizures. There may also be some “complex” symptoms called automatisms. Automatisms consist of involuntary but coordinated movements that tend to be purposeless and repetitive. Common automatisms include lip smacking, chewing, fidgeting, and walking.
The third kind of partial seizure is one that begins as a focal seizure and evolves into a generalized convulsive (“grand-mal”) seizure. Most patients with partial seizures have simple partial, complex partial, and secondarily generalized seizures. In about two-thirds of patients with partial epilepsy, seizures can be controlled with medications. Partial seizures that cannot be treated with drugs can often be treated surgically.”