Muscle Diseases - Epilepsy
Epilepsy is a common disorder of the human nervous system. In the United States, alone, more than four million people suffer from epilepsy.
Epilepsy affects all kinds of people, regardless of sex, intelligence, or standard of living.
Causes and Precipitating Factors
The onset of epilepsy is caused by damage to a small group of cells in the brain. This damage may be caused before birth as a result of a shortage of oxygen during labor or delivery. More commonly it is the post birth result of infection, poisoning, brain tumors, stroke, high fever, or some form of trauma, usually to the head. A single epileptic seizure usually occurs spontaneously. In some cases, seizures are triggered by visual stimuli, such as a flickering image on a television screen, a sudden change from dark to very bright illumination, or vice versa. Other patients may react to auditory stimuli such as a loud noise, a monotonous sound, or even to certain musical notes. A seizure is accompanied by a discharge of nerve impulses, which can be detected by electroencephalography. The effect is something like that of a telephone switchboard in which a defect in the circuits accidentally causes wrong number calls. The forms that seizures take depend upon the location of the nervous system disturbances within the brain and the spread of the nerve impulses. Physicians have found that certain kinds of epilepsy cases can be traced to specific areas of the brain where the lesion has occurred.
Epilepsy can develop at any age, although nearly 85 percent of all cases appear before the age of 20 years. Hence, it is commonly seen as an affliction of children. There is no indication that epilepsy itself can be inherited, but some evidence exists that certain individuals inherit a greater tendency to develop the condition from precipitating causes than is true for the general population. According to the Epilepsy Foundation, studies show that if neither parent has epilepsy, the chances are one in 100 that they will have an epileptic child, but the chances rise to one in 40 if one parent is epileptic.
About 70 percent of epilepsy cases are idiopathic —that is, they are not attributable to any known cause. In the remaining 30 percent, the recurrent seizures are symptomatic — they are symptoms of some definite brain lesion, either congenital or resulting from subsequent injury. Because it can reasonably be assumed that some of the idiopathic cases are a result of lesions that have not been identified, epilepsy is perhaps best regarded not as a specific disease but as a symptom of a brain abnormality due to any of various causes.
Aura Preceding a Seizure
Unusual sensory experiences have been reported to occur before a seizure by about half the victims of epilepsy. The sensation, which is called an aura , may appear in the form of an unpleasant odor, a tingling numbness, a sinking or gripping feeling, strangulation, palpitations, or a gastrointestinal sensation. Some patients say the sensation cannot be described. Others report feeling strange or confused for hours or even days before a seizure. Such an early warning is known as a prodrome .
The various types of epilepsy can be broadly grouped under four general categories: grand mal, petit mal, focal, and psychomotor. Only one feature is common to all types of epilepsy—the sudden, disorderly discharge of nerve impulses within the brain.
Grand Mal Seizure
The grand mal is a generalized convulsion during which the patient may initially look strange or bewildered, suddenly groan or scream, lose consciousness and become stiff ( tonic phase ), hold the breath, fall to the ground unless supported, and then begin to jerk the arms and legs ( clonk phase ). There may be loss of bowel and bladder control. The tongue may be bitten by coming between clenched jaws. The duration of the entire seizure, both the tonic and clonic phases, is less than two minutes—frequently less than one minute—followed by postconvulsive confusion or deep sleep that may last for minutes or hours.
Variations in the Pattern
The sequence of events in grand mal seizures is not invariable. The tongue-biting and urinary and fecal incontinence do not occur as frequently in children as in adult patients. Children may also demonstrate a type of grand mal seizure in which the patient suddenly becomes limp and falls to the floor unconscious; there is no apparent tonic or clonic phase and the muscles do not become stiff. Other cases may manifest only the tonic phase, with unconsciousness and the muscles remaining in a stiffened, tonic state throughout the seizure. There also is a clonic type of seizure, which begins with rapid jerking movements that continue during the entire attack. In one very serious form of convulsive seizure known as status epilepticus , repeated grand mal seizures occur without the victim's becoming conscious between them.
Petit Mal Seizure
Petit mal seizures are characterized by momentary staring spells, as if the patient were suspended in the middle of his activity. He may have a blank stare or undergo rapid blinking, sometimes accompanied by small twitching movements in one part of the body or another—hands, legs, or facial muscles. He does not fall down.
These spells, called absence or lapse attacks , usually begin in childhood before puberty. The attacks are typically very brief, lasting half a minute or less, and occur many times throughout the day. They may go unnoticed for weeks or months because the patient appears to be daydreaming.
Focal seizures proceed from neural discharges in one part of the brain, resulting in twitching movements in a corresponding part of the body. Usually, one side of the face, the thumb and fingers of one hand, or one entire side of the body is involved. The patient does not lose consciousness and may in fact remain aware of his surroundings and the circumstances during the entire focal convulsion. Focal convulsions in adults commonly indicate some focal abnormality, but this is less true in a child who may have a focal seizure without evidence of a related brain lesion.
With their knowledge of the nerve links between brain centers and body muscles, physicians are able to determine quite accurately the site of a brain lesion that is involved with a focal seizure.
One type of focal seizure has a distinctive pattern and is sometimes called a Jacksonian seizure , and the condition itself Jacksonian epilepsy . The attack begins with rhythmic twitching of muscles in one hand or one foot or one side of the face. The spasmodic movement or twitching then spreads from the body area first affected to other muscles on the same side of the body. The course of the twitching may, for example, begin on the left side of the face, then spread to the neck, down the arm, then along the trunk to the foot. Or the onset of the attack may begin at the foot and gradually spread upward along the trunk to the facial muscles. There may be a tingling or burning sensation and perspiration, and the hair may stand up on the skin of the areas affected.
Psychomotor seizures , or temporal lobe seizures , often take the form of movements that appear purposeful but are irrelevant to the situation. Instead of losing control of his thoughts and actions, the patient behaves as if he is in a trancelike state. He may smack his lips and make chewing motions. He may suddenly rise from a chair and walk about while removing his clothes. He may attempt to speak or speak incoherently, repeating certain words or phrases, or he may go through the motions of some mechanical procedure, like driving a car, for example.
The patient in a psychomotor seizure usually does not respond to questions or commands. If physically restrained during a psychomotor episode, the patient may appear belligerent and obstreperous, or he may resist with great energy and violence. Usually, the entire episode lasts only a few minutes. When the seizure ends, the patient is confused and unable to recall clearly what has happened.
The aura experienced by victims of psychomotor seizures may differ from that of other forms of the disorder. The psychomotor epileptic may have sensations of taste or smell, but more likely will experience a complex illusion or hallucination that may have the quality of a vivid dream. The hallucination may be based on actual experiences or things the patient has seen, or it may deal with objects or experiences that only seem familiar though they are in fact unfamiliar. This distortion of memory, in which a strange experience seems to be a part of one's past life, is known as déjà vu , which in French means literally “already seen.”
Other visual associations involved in various forms of epilepsy include those in which the patient experiences sensations of color, moving lights, or darkness. Red is the most common color observed in visual seizures, although blue, yellow, and green also are reported. The darkness illusion may occur as a temporary blindness, lasting only a few minutes. Stars or moving lights may appear as if visible to only one eye, indicating that the source of the disturbance is a lesion in the brain area on the opposite side of the head. Visual illusions before an epileptic attack may have a distorted quality, or consist of objects arranged in an unnatural pattern or of an unnatural size.
Auditory illusions, on the other hand, are comparatively rare. Occasionally a patient will report hearing buzzing or roaring noises as part of a seizure, or human voices repeating certain recognizable words.
Treatment of the Epileptic Patient
Usually the physician does not see the patient during a seizure and must rely on the description of others to make a proper diagnosis. Because the patient has no clear recollection of what happens during any of the epileptic convulsions, it is wise to have someone who has seen an attack accompany him to a physician. First, the physician begins the detective work to find the cause of the seizure. He will examine the patient thoroughly, obtain blood tests, an electroencephalogram, and a lumbar puncture, if indicated. Even after all these studies, however, the physician often can find no specific cause that can be eradicated. Efforts are then made to control the symptoms.
The treatment of epilepsy consists primarily of medication for the prevention of seizures. It is usually highly effective. About half of all patients are completely controlled and another quarter have a significant reduction in the frequency and severity of attacks. The medication, usually in tablet or capsule form, must be taken regularly according to the instructions of the physician. It may be necessary to try several drugs over a period of time to determine which drug or combination of drugs best controls the seizures. Phenobarbital and diphenylhydantoin (Dilantin) may be prescribed for the control of grand mal seizures and focal epilepsy, and the physician may find that a combination of these drugs or others offers the best anticonvulsant control. Tri-methadione frequently is administered to petit mal patients; primidone or phenobarbital may be prescribed for psychomotor attacks.
Antispasmodic drugs such as diazepam have been shown to be useful in controlling prolonged, repeated, generalized seizures. A new diazepam gel reduces the numbers of seizures that occur in clusters.
Surgery is an option for those who do not respond to drug treatment, but is not always effective.
However, medicine and surgery are not the only treatments for epilepsy patients. Emotional factors are known to influence convulsive disorders. Lessening a patient's anger, anxiety, and fear can help to control the condition. An understanding family and friends are important, as are adequate rest, good nutrition, and proper exercise. The exercise program should not include vigorous contact sports, and some activities such as swimming should not be performed by the patient unless he is accompanied by another person who understands the condition and is capable of helping the epileptic during a seizure.
There is nothing permanent about epilepsy, although some patients may endure the symptoms for much of their lives. It is a disorder that changes appreciably and constantly in form and manifestations. Some experts claim that petit mal and psychomotor cases if untreated may progress to more serious cases of grand mal seizures. On the other hand, epilepsy that is given proper medical attention may eventually subside in frequency and severity of attacks. In many cases, seizures disappear or subside within a short time and treatment can be discontinued gradually.
While some effort has been made by medical scientists to determine if there is an “epileptic personality,” evidence indicates there is no typical personality pattern involved. Whatever behavior patterns and emotional reactions are observed are the result of individual personality makeup rather than being directly related to epilepsy. Most epilepsy patients are capable of performing satisfactory work at various jobs; one study showed that only nine percent were partially dependent and four percent were incapable of holding a job. In some areas there may be restrictions on issuing driver's licenses to epileptics or other legal regulations that limit normal activities for epilepsy patients. As a result, some epileptics may conceal their condition or avoid medical treatment that might be reported to government agencies.
Because of ignorance and misinformation, some people regard epilepsy as frightening or mysterious, and patients may suffer unnecessarily and unjustly. In fact, behavioral abnormalities in patients with seizures are commonly the reflection of how they are viewed by others.
When epilepsy has been diagnosed in a child, the parents must be instructed about the condition and the need for continuous careful medical supervision. If the child is old enough to understand, he also should learn more about the nature of the condition. Misbeliefs should be corrected. Both parents and child should understand that seizures are not likely to be fatal and that a brain lesion does not lead to mental deterioration. Parents and child should learn what actions should be taken in the event of a seizure, such as loosening clothing and taking steps to prevent injury. Natural concern should be balanced with an understanding that overprotection may itself become a handicap. The child should be encouraged to participate in social and physical activities at school and in the neighborhood as long as they do not strain his capabilities. Finally, parents should notfeel guilty aboutthe child's condition and think that some action of theirs contributed to the child's condition. See “Epileptic Seizures” in Ch. 35, Medical Emergencies , for a description of what to do when a seizure occurs.
Further information about epilepsy, including causes, effects, treatment, rehabilitation, and laws regulating employment and driver permits, can be obtained from the Epilepsy Foundation of America, 4351 Garden City Dr., Landover, MD 20785, and from the U.S. Department of Health and Human Services, Public Health Service, National Institutes of Health, Bethesda, MD 20892.
Maintaining immunization against disease is crucial, especially haemophilus influenza, which causes high fever that could trigger epilepsy.