Epilepsy (Seizure Disorders)

Definition

Seizure disorders represent a set of disorders of cerebral function in which recurrent, sudden and brief discharges of brain neurons occur that can cause a combination of transient motor, sensory and behavioral abnormalities. "Epilepsy" is the common term for these recurrent episodes.

Description

There are many forms of epilepsy, each with its own characteristic symptoms. Whatever the form, the disease is caused by a problem in communication between the brain's nerve cells. Normally, such cells communicate with one another by sending tiny electrical signals back and forth. For someone with epilepsy, the signals from one group of nerve cells occasionally become too strong – so strong that they overwhelm neighboring parts of the brain.

It is this sudden, excessive electrical discharge that causes the basic symptom of epilepsy, which is called an epileptic seizure, fit, or convulsion. It is not yet known what causes the brain's communication system to misfire in this fashion, or why such events recur in some people.

Exhaustive research, including the testing of great numbers of epileptics, has shown that roughly two out of three epileptics have no identifiable structural abnormality in the brain, that is, there is nothing that is visibly wrong. The epilepsy of the remaining one-third can generally be traced back to an underlying problem such as brain damage at birth, severe head injury or brain-tissue infection. Occasionally the condition may be caused by a brain tumor. This is especially likely when epilepsy appears for the first time in adulthood.

The two major types are petit mal and grand mal:

Petit mal epilepsy is a disease of childhood that does not usually persist past late adolescence. A child may have this form of epilepsy if, from time to time, he or she suddenly stops whatever activity is going on and stares blankly around for a few seconds (sometimes up to half a minute). During the blank interval, known as a petit mal seizure, the child is unaware of what is happening. There may be a slight jerking movement of the head or an arm, but petit mal seizures do not generally involve falling to the ground. When the seizure ends, the child often does not realize that the brief blank spell has occurred. Such children are sometimes thought simply to be "day-dreamers."

The most characteristic symptom of grand mal epilepsy is a much more dramatic seizure. The person falls to the ground unconscious and then the entire body stiffens. Next, it twitches or jerks uncontrollably. This may last for several minutes and is usually followed by a period of deep sleep or mental confusion.

During a seizure, some people lose bladder control and pass urine freely. In many cases, the person gets a warning of an impending seizure by having certain strange sensations before losing consciousness.

Any such warning is known as an aura, and an aura can occur just prior to the occurrence of the seizure or as much as several hours before it strikes. It may consist of nothing but a sense of tension or some other ill-defined feeling, but some epileptics have quite specific auras such as an impression of smelling unpleasant odors or hearing peculiar sounds, distorted vision, or an odd bodily sensation, particularly in the stomach. Many epileptics learn to recognize their special aura, and this may give them time to avoid accidents when they become unconscious.

Other types of epilepsy are much less common than petit and grand mal. Two additional types are called focal epilepsy and temporal lobe epilepsy. A person with focal epilepsy does not necessarily lose consciousness; the seizure begins with uncontrollable twitching of a small part of the body, and the twitch gradually spreads. The thumb of one hand, for instance, may start to jerk, followed by a jerking of the entire arm and then of the rest of that side of the body, after which there may be a more generalized seizure of the entire body.

A person with temporal lobe epilepsy is likely to have an aura lasting only a few seconds. Then, without being aware, the individual does something entirely out of character, such as becoming suddenly angry, laughing for no apparent reason, or interrupting normal activity with some sort of bizarre behavior. Strange, chewing movements of the mouth are apt to occur throughout any such episode.

The basic symptom of epilepsy is a brief and abnormal phase of behavior, commonly known as a seizure, fit or convulsion. It is important to realize that a single such episode does not indicate that you have epilepsy. By definition, epileptic seizures recur.

Treatment

First aid for epilepsy is basically very simple and is designed to protect the safety of the person until the seizure stops naturally by itself. These are the key things to remember:

• Keep calm and reassure other people who may be nearby.

• Clear the area around the person of anything hard or sharp.

• Loosen ties or anything round the neck that may make breathing difficult.

• Put something flat and soft, like a folded jacket, under the head. Turn him gently onto his side. This will help keep the airway clear.

• Do not try to force the mouth open with any hard implement or with fingers. It is not true that a person having a seizure can swallow his tongue, and efforts to hold the tongue down can injure his/her teeth or jaw.

• Don't hold the person down or try to stop his movements.

• Don't attempt artificial respiration, except in the unlikely event that a person does not start breathing again after the seizure has stopped.

• Stay with the person until the seizure ends naturally.

• Be friendly and reassuring as consciousness returns.

• Offer to call a taxi, friend or relative to help the person get home if he seems confused or unable to get home by himself.

Prevention

Years ago, a diagnosis of epilepsy was more or less a guarantee that seizures would continue to take place in the future. But fortunately things are different today, and there are ways to prevent subsequent seizures. In many cases, these methods are so successful that people go for years with complete seizure control. Epileptic seizures can be prevented by:

• regular use of anti-seizure medication

• removal of brain tissue where seizures take place

• special diet to produce a change in body chemistry

• avoidance of special conditions known to trigger seizures in susceptible people.

Of the methods listed above, drug therapy is by far the most often used and is almost always the method tried first. Sixteen medications to prevent epileptic seizures are currently approved for use in the U.S., and of these, the following six are used most frequently: Phenytoin (Dilantin), phenobarbital, ethosuximide (Zarontin), primidone (Mysoline), valproic acid (Depakene) and carbamazepine (Tegretol).

When taken regularly as prescribed, medication can prevent seizures in about half of all cases and produce improvement in about 30 percent of all cases. The remaining patients do not get much relief from existing medications.

When drugs fail to prevent seizures, surgery may be an option, but surgery is only possible when the seizures begin in one fairly small part of the brain that can be removed without affecting speech, memory or some other important brain function. Although surgery is not used as often as drug therapy, the results are similar – about 70 percent of all patients getting either full or greatly improved control of seizures, and the rest have only a slight improvement or none at all.

Questions to Ask Your Doctor

What type of epilepsy is it?

Is there a test to diagnose epilepsy? How early in life can you be tested?

Is epilepsy hereditary?

Can a normal life be lead? (i.e., driving, swimming, working)

What type of medication do you recommend? What are the side effects?

Does this type of epilepsy require surgery? If so, what is the success rate?

Is epilepsy curable?