Epilepsy is a chronic (long-lasting) medical condition marked by recurrent epileptic seizures. An epileptic seizure is an event of an altered brain function caused by abnormal, or excessive, electrical discharges from brain cells.
- Epilepsy affects up to one percent of the population in the United States.
- There are different types of seizures, different types of epilepsy syndromes, and different causes of epilepsy.
- In general, medicines can control seizures in about 70 percent of epilepsy patients.
- For patients with uncontrollable epilepsy, epilepsy surgery can provide a "cure" by eliminating the source of seizures and epilepsy.
Classifying the type of seizure is very important and will help your doctor plan the treatment you need.
Generalized epilepsy involves seizures produced by abnormal electrical activity throughout the brain. The seizures can result from a genetic predisposition in an otherwise healthy person or as a consequence of widespread disturbance of brain function. You may experience different types of generalized seizures or the type may vary from one seizure to another.
|Generalized Seizures||Typical Symptoms|
|"Grand Mal" or Generalized Tonic-Clonic||Loss of consciousness, rigid muscles, whole-body convulsions; can cause a fall if you are standing|
|Absence||Staring with brief loss of consciousness; fluttering eyelids|
|Myoclonic||Sporadic or repeated, brief jerks of the limbs|
|Clonic||Repetitive, rhythmic jerking movements of head or limbs|
|Tonic||Loss of consciousness, stiffness and rigidity of the whole body; can cause a fall if you are standing|
|Atonic||Loss of muscle tone in head or body; can cause a fall if you are standing|
Partial (Focal) Epilepsy
Partial or focal epilepsy involves seizures produced by electrical impulses that start in a relatively small region of the brain. The part of the brain generating the seizures is sometimes called the focus. In simple partial seizures, the patient retains awareness, whereas complex partial seizures cause the patient to lose awareness.
These seizures can vary in type in the same patient, or go from simple partial to complex partial, or even to generalized seizures. Partial seizures imply some localized brain disease caused by head injury, stroke, tumor, scar or developmental anomaly. The cause can sometimes be detected on imaging tests but, in many instances, it remains unknown. Rarely are partial seizures related to a genetic predisposition.
|Partial (Focal) Seizures||Typical Symptoms|
|Simple partial (no loss of awareness)||Simple motor: Jerking, stiffening confined to one side of head or body
Simple sensory (auras): Unusual sensations affecting vision, hearing, smell, taste or touch, or memory or emotional disturbances; possibility of racing heart, hot and cold feelings
|Complex partial (impaired awareness)||Staring, unresponsiveness; automatisms such as lip smacking, chewing, fidgeting, and other repetitive, involuntary but coordinated movements|
|Partial with secondary generalization||Milder seizure symptoms listed above lead to loss of consciousness and convulsions|
Two other types of attacks can look very much like an epileptic seizure, but are not epileptic in nature because they do not involve abnormal electrical activity in the brain:
- Non-epileptic seizures can involve loss of consciousness, abnormal movements, jerks and falls. They are usually related to psychological or emotional stress.
- Convulsive syncope describes fainting from a cardiac or circulatory cause, accompanied by stiffening or jerks that can mimic epilepsy.
Generally, patients with seizures that start in a focal area of the brain, and whose seizures have not been controlled with medicine, are considered for surgery. This region might be small or might involve several lobes of the brain. Typically, a comprehensive pre-surgical evaluation begins with EEG-video monitoring and a high-resolution brain MRI before a patient is recommended for epilepsy surgery.
Jorge Alvaro Gonzalez-Martinez, MD, Cleveland Clinic Neurosurgery Specialist
Learn More About Common Seizures
Some of the common types of seizures are described below.
Generalized Tonic Clone Seizures (Grand Mal Seizures)
Generalized Tonic Clonic, or Grand Mal seizures, are what most people think of when they hear about seizures. Although it may seem very long, most grand mal seizures last less than two minutes.
During Grand Mal seizures, the patient loses awareness, manifests a tightening and contraction of all the muscles of the body, groans, and may show labored respirations. This is followed by a jerking of muscles which gradually slows down and stops, leaving the patient in an exhausted and unarousable state for several minutes. This state of exhaustion is referred to as the post-ictal state.
Generalized Grand Mal seizures are physically violent and could result in falls and injury. If you are witnessing such a grand mal event, it is important to lay the patient on a flat surface and place them on his or her side.
Do not attempt to open a seizing person’s mouth as this is more likely to injure you or the patient or result in aspiration of the object into their lungs. A common myth about grand mal seizures is that the patient may “swallow their tongue." This never occurs.
Absence seizures are also known as “petit mal” seizures. These are more common in children and consist of brief episodes of staring. Unlike Grand Mal seizures, they are often brief (five to 20 seconds) and occur multiple times each day. Children with absence seizures may be mistakenly thought to be "daydreamers" in school. 50 to 70 percent of patients “outgrow” absence seizures by late adolescence.
Partial (Focal) Seizures
Partial seizures are one of the most common types of seizures which involve a part of the brain. Most often they arise from the temporal lobe, however, they can also begin in the frontal, occipital and parietal lobes. The patient may cease their activity, stare, engage in semipurposive activity like lip smacking, chewing, swallowing, picking at their clothes or other objects.
They may or may not interact with or be aware of their surroundings. This may result in confusion, combativeness or wandering about, putting them at risk for sustaining injuries. As an observer, it is important that one maintain a cool and calm demeanor while preventing the patient from experiencing any harm.
If they spread to involve a large enough area of the brain, partial seizures can turn into a generalized tonic-clonic seizure. So it is possible for a patient to have both types of seizures.