Epilepsy

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Epilepsy

Definition

Epilepsy is a condition characterized by recurrent seizures that may include repetitive muscle jerking called convulsions. A seizure is a sudden disruption of the brain's normal electrical activity accompanied by altered consciousness and/or other neurological and behavioral manifestations.

Description

Epilepsy affects 1–2% of the population of the United States. Although epilepsy is as common in adults over 60 as in children under 10, 25% of all cases develop before the age of five. One in every two cases develops before the age of 25. About 125,000 new cases of epilepsy are diagnosed each year, and a significant number of children and adults that have not been diagnosed or treated have epilepsy.

Most seizures are benign, but a seizure that lasts a long time can lead to status epilepticus, a life-threatening condition characterized by continuous seizures, sustained loss of consciousness, and respiratory distress. Nonconvulsive epilepsy can impair physical coordination, vision, and other senses. Undiagnosed seizures can lead to conditions that are more serious and more difficult to manage.

Types of seizures

Generalized epileptic seizures occur when electrical abnormalities exist throughout the brain. A partial seizure does not involve the entire brain. A partial seizure begins in an area called an epileptic focus, but may spread to other parts of the brain and cause a generalized seizure. Some people who have epilepsy have more than one type of seizure.

Motor attacks cause parts of the body to jerk repeatedly. A motor attack usually lasts less than an hour and may last only a few minutes. Sensory seizures begin with numbness or tingling in one area. The sensation may move along one side of the body or the back before subsiding.

Visual seizures that affect the area of the brain that controls sight cause people to hallucinate. Auditory seizures affect the part of the brain that controls hearing and cause the patient to imagine hearing voices, music, and other sounds. Other types of seizures can cause confusion, upset stomach, or emotional distress.

PARTIAL SEIZURES. Simple partial seizures do not spread from the focal area where they arise. Symptoms are determined by the part of the brain affected. The patient usually remains conscious during the seizure and can later describe it in detail.

COMPLEX PARTIAL SEIZURES. A distinctive smell, taste, or other unusual sensation (aura) may signal the start of a complex partial seizure.

Complex partial seizures start as simple partial seizures, but move beyond the focal area and cause loss of consciousness. Complex partial seizures can become major motor seizures. Although a person having a complex partial seizure may not seem to be unconscious, he or she does not know what is happening and may behave inappropriately. He or she will not remember the seizure, but may seem confused or intoxicated for a few minutes after it ends.

Causes & symptoms

The origin of 50–70% of all cases of epilepsy is unknown. Epilepsy sometimes results from trauma at birth. Such causes include insufficient oxygen to the brain; head injury; heavy bleeding or incompatibility between a woman's blood and the blood of her newborn baby; and infection immediately before, after, or at the time of birth.

Other causes of epilepsy include:

head trauma resulting from a car accident, gunshot wound, or other injury
alcoholism
brain abscess or inflammation of membranes covering the brain or spinal cord
phenylketonuria (PKU), a disease that is present at birth, is often characterized by seizures, and can result in mental retardation
other inherited disorders
infectious diseases such as measles, mumps , and diphtheria
degenerative disease
lead poisoning, mercury poisoning, carbon monoxide poisoning, or ingestion of some other poisonous substance
genetic factors

Status epilepticus, a condition in which a person suffers from continuous seizures and may have trouble breathing, can be caused by:

suddenly discontinuing antiseizure medication
hypoxic or metabolic encephalopathy (brain disease resulting from lack of oxygen or malfunctioning of other physical or chemical processes)
acute head injury
infection spread from blood (for example, meningitis or encephalitis) caused by inflammation of the brain or the membranes that cover it

Diagnosis

Personal and family medical history, description of seizure activity, and physical and neurological examinations help primary care physicians, neurologists, and epileptologists diagnose this disorder. Doctors rule out conditions that cause symptoms that resemble epilepsy, including small strokes (transient ischemic attacks, or TIAs), fainting (syncope), pseudoseizures, and sleep attacks (narcolepsy ).

Neuropsychological testing uncovers learning or memory problems. Neuroimaging provides views of brain areas involved in seizure activity.

The electroencephalogram (EEG) is the main test used to diagnose epilepsy. EEGs use electrodes placed on or within the skull to record the brain's electrical activity and pinpoint the exact location of abnormal discharges.

The patient may be asked to remain motionless during a short-term EEG or to go about his normal activities during extended monitoring. Some patients are deprived of sleep or exposed to seizure triggers, such as rapid, deep breathing (hyperventilation) or flashing lights (photic stimulation). In some cases, people may be hospitalized for EEG monitorings that can last as long as two weeks. Video EEGs also document what the patient was doing when the seizure occurred and how the seizure changed his or her behavior.

Other techniques used to diagnose epilepsy include:

Magnetic resonance imaging (MRI), which provides clear, detailed images of the brain. Functional MRI (fMRI), performed while the patient does various tasks, can measure shifts in electrical intensity and blood flow and indicate which brain region each activity affects.
Positron emission tomography (PET) and single photon emission tomography (SPECT) monitor blood flow and chemical activity in the brain area being tested. PET and SPECT are very effective in locating the brain region where metabolic changes take place between seizures.

Treatment

Relaxation techniques

Stress increases seizure activity in 30% of people who have epilepsy. Relaxation techniques can provide some sense of control over the disorder, but they should never be used instead of antiseizure medication or without the approval of the patient's doctor. Yoga, meditation , and favorite pastimes help some people relax and manage stress more successfully. Biofeedback can teach adults and older adolescents how to recognize an aura and what to do to stop its spread. Children under 14 usually are not able to understand and apply principles of biofeedback.

Acupuncture

Acupuncture treatments (acupuncture needles inserted for a few minutes or left in place for as long as 30 minutes) make some people feel pleasantly relaxed.

Acupressure

Acupressure can have the same effect on children or on adults who dislike needles.

Aromatherapy

Aromatherapy involves mixing aromatic plant oils into water or other oils and massaging them into the skin or using a special burner to waft their fragrance throughout the room. Aromatherapy oils affect the body and the brain, and undiluted oils should never be applied directly to the skin. Ylang ylang, chamomile , or lavender can create a soothing mood. People who have epilepsy should not use rosemary, hyssop , citrus (such as lemon), sage , or sweet fennel , which seem to stimulate the brain.

Nutritional therapy

KETOGENIC DIET. A special high-fat, low-protein, low-carbohydrate diet is sometimes used to treat patients whose severe seizures have not responded to other treatment. Calculated according to age, height, and weight, the ketogenic diet induces mild starvation and dehydration. This forces the body to create an excessive supply of ketones, natural chemicals with seizure-suppressing properties.

The goal of this controversial approach is to maintain or improve seizure control while reducing medication. The ketogenic diet works best with children between the ages of one and 10. It is introduced over a period of several days, and most children are hospitalized during the early stages of treatment.

If a child following this diet remains seizure-free for at least six months, increased amounts of carbohydrates and protein are gradually added. If the child shows no improvement after three months, the diet is gradually discontinued. A 2003 study of the diet and its effect on growth noted that if used, clinicians should recommend adequate intake of energy and protein and a higher proportion of unsaturated to saturated dietary fats. The report also recommended use of vitamin and mineral supplements with the diet.

Introduced in the 1920s, the ketogenic diet has had limited, short–term success in controlling seizure activity. Its use exposes patients to such potentially harmful side effects as:

staphylococcal infections
stunted or delayed growth
low blood sugar (hypoglycemia)
excess fat in the blood (hyperlipidemia)
disease resulting from calcium deposits in the urinary tract (urolithiasis)
disease of the optic nerve (optic neuropathy)

Homeopathy

Homeopathic therapy also can work for people with seizures, especially constitutional homeopathic treatment that acts at the deepest levels to address the needs of the individual person.

Allopathic treatment

The goal of epilepsy treatment is to eliminate seizures or make the symptoms less frequent and less severe. Long-term anticonvulsant drug therapy is the most common form of epilepsy treatment.

Medication

A combination of drugs may be needed to control some symptoms, but most patients who have epilepsy take one of the following medications:

Dilantin (phenytoin)
Tegretol (carbamazepine)
Barbita (phenobarbital)
Mysoline (primidone)
Depakene (valproic acid, sodium valproate)
Klonopin (clonazepam)
Zarontin (ethosuximide)

Dilantin, Tegretol, Barbita, and Mysoline are used to manage or control generalized tonic-clonic and complex partial seizures. Depakene, Klonopin, and Zarontin are prescribed for patients who have absence seizures.

Neurontin (gabapentin), Lamictal (lamotrigine), and topiramate (Topamax) are among medications more recently approved in the United States to treat adults who have partial seizures or partial and grand mal seizures. Another new medication called Levetiracetam (Keppra) has been approved and shows particularly good results in reducing partial seizures among elderly patients with few side effects. This is important, because elderly patients often have other conditions and must take other medications that might interact with seizure medications. In 2003, Keppra's manufacturer was working on a new antiepilectic drug from the same chemical family as Keppra that should be more potent and effective. Available medications frequently change, and the physician will determine the best treatment for an individual patient. A 2003 report found that monotherapy, or using just one medication rather than a combination, works better for most patients. The less complicated the treatment, the more likely the patient will comply and better manager the seizure disorder.

Even an epileptic patient whose seizures are well controlled should have regular blood tests to measure levels of antiseizure medication in his or her system and to check to see if the medication is causing any changes in his or her blood or liver. A doctor should be notified if any signs of drug toxicity appear, including uncontrolled eye movements; sluggishness, dizziness , or hyperactivity; inability to see clearly or speak distinctly; nausea or vomiting ; or sleep problems.

Status epilepticus requires emergency treatment, usually with Valium (Ativan), Dilantin, or Barbita. An intravenous dextrose (sugar) solution is given to a patient whose condition is due to low blood sugar, and a vitamin B₁ preparation is administered intravenously when status epilepticus results from chronic alcohol withdrawal. Because dextrose and thiamine are essentially harmless and because delay in treatment can be disastrous, these medications are given routinely, as it is usually difficult to obtain an adequate history from a patient suffering from status epilepticus.

Intractable seizures are seizures that cannot be controlled with medication or without sedation or other unacceptable side effects. Surgery may be used to eliminate or control intractable seizures.

Surgery

Surgery can be used to treat patients whose intractable seizures stem from small focal lesions that can be removed without endangering the patient, changing the patient's personality, dulling the patient's senses, or reducing the patient's ability to function.

A physical examination is conducted to verify that a patient's seizures are caused by epilepsy, and surgery is not used to treat patients with severe psychiatric disturbances or medical problems that raise risk factors to unacceptable levels.

Surgery is never recommended unless:

The best available antiseizure medications have failed to control the patient's symptoms satisfactorily.
The origin of the patient's seizures has been precisely located.
There is good reason to believe that surgery will significantly improve the patient's health and quality of life.

Every patient considering epilepsy surgery is carefully evaluated by one or more neurologists, neurosurgeons, neuropsychologists, and/or social workers. A psychiatrist, chaplain, or other spiritual advisor may help the patient and his family cope with the stresses that occur during and after the selection process.

TYPES OF SURGERY. Surgical techniques used to treat intractable epilepsy include:

Lesionectomy. Removing the lesion (diseased brain tissue) and some surrounding brain tissue is very effective in controlling seizures. Lesionectomy is generally more successful than surgery performed on patients whose seizures are not caused by clearly defined lesions, but removing only part of the lesion lessens the effectiveness of the procedure.
Temporal resections. Removing part of the temporal lobe and the part of the brain associated with feelings, memory, and emotions (the hippocampus) provides good or excellent seizure control in 75–80% of properly selected patients with appropriate types of temporal lobe epilepsy. Some patients experience post-operative speech and memory problems.
Extra-temporal resection. This procedure involves removing some or all of the frontal lobe, the part of the brain directly behind the forehead. The frontal lobe helps regulate movement, planning, judgment, and personality. Special care must be taken to prevent post-operative problems with movement and speech. Extra-temporal resection is most successful in patients whose seizures are not widespread.
Hemispherectomy. This method of removing brain tissue is restricted to patients with severe epilepsy and abnormal discharges that often extend from one side of the brain to the other. Hemispherectomies are most often performed on infants or young children who have had an extensive brain disease or disorder since birth or from a very young age.
Corpus callosotomy. This procedure, an alternative to hemispherectomy in patients with congenital hemiplegia, removes some or all of the white matter that separates the two halves of the brain. Corpus callosotomy is performed almost exclusively on children who are frequently injured during falls caused by seizures. If removing two–thirds of the corpus callosum does not produce lasting improvement in the patient's condition, the remaining one-third will be removed during another operation.
Multiple subpial transection. This procedure is used to control the spread of seizures that originate in or affect the "eloquent" cortex, the area of the brain responsible for complex thought and reasoning.

Other forms of treatment

VAGUS NERVE STIMULATION. Approved for adults and adolescents (over 16 years old) with intractable seizures, vagus nerve stimulation (VNS) uses a pacemaker-like device implanted under the skin in the upper left chest, to provide intermittent stimulation to the vagus nerve. Stretching from the side of the neck into the brain, the vagus nerve affects swallowing, speech, breathing, and many other functions, and VNS may prevent or shorten some seizures.

First aid for seizures

A person with epilepsy having a seizure should not be restrained, but sharp or dangerous objects should be moved out of reach. Anyone having a complex partial seizure can be warned away from danger by someone calling his/her name in a clear, calm voice.

A person with epilepsy having a grand mal seizure should be helped to lie down, and those aiding the patient should contact emergency medical personnel. Tight clothing should be loosened. A soft, flat object like a towel or the palm of a hand should be placed under the person's head. Forcing a hard object into the mouth of someone having a grand mal seizure could cause injuries or breathing problems. If the person's mouth is open, placing a folded cloth or other soft object between his or her teeth will protect the tongue. Turning the patient's head to the side will help with breathing. After a grand mal seizure has ended, the person who had the seizure should be told what has happened and reminded of where he or she is.

Expected results

People who have epilepsy have a higher than average rate of suicide; sudden, unexplained death; and drowning and other accidental fatalities.

Benign focal epilepsy of childhood and some absence seizures may disappear in time, but remission is unlikely if seizures occur several times a day, several times in a 48-hour period, or more frequently than in the past.

Epilepsy can be partially or completely controlled if the individual takes antiseizure medication according to directions; avoids seizure-inducing sights, sounds, and other triggers; gets enough sleep; and eats regular, balanced meals.

Anyone who has epilepsy should wear a bracelet or necklace identifying the seizure disorder and listing the medication he or she takes.

Prevention

Eating properly, getting enough sleep, and controlling stress and fevers can help prevent seizures. A person who has epilepsy should be careful not to hyperventilate. Those who experience auras should find a safe place to lie down and stay until the seizure passes. Anticonvulsant medications should not be stopped suddenly and, if other medications are prescribed or discontinued, the doctor treating the seizures should be notified. In some conditions, such as severe head injury, brain surgery, or subarachnoid hemorrhage, anticonvulsant medications may be given to the patient to prevent seizures.

Resources

BOOKS

"Seizures." Reader's Digest Guide to Medical Cures & Treatments : A Complete A-to-Z Sourcebook of Medical Treatments, Alternative Opinions, and Home Remedies. Canada: The Reader's Digest Association, Inc., 1996.

Shaw, Michael, ed. Everything You Need to Know about Diseases. Springhouse, PA: Springhouse Corporation, 1996.

PERIODICALS

Batchelor, Lori, et al. "An Interdisciplinary Approach to Implementing the Ketogenic Diet for the Treatment of Seizures." Pediatric Nursing (September/October 1997): 465–471.

"Data Analysis Shows Keppra Reduced Partial Seizures in Elderly Patients." Clinical Trials Week (April 28, 2003): 26.

Dichter, M.A., and M.J. Brodie. "Drug Therapy: New Antiepileptic Drugs." The New England Journal of Medicine (15 June 1996): 1583-1588.

Dilorio, Colleen, et al. "The Epilelpsy Medication and Treatment Complexity Index: Reliability and Validity Testing." Journal of Neuroscience Nursing (June 2003): 155–158.

"Epilepsy Surgery and Vagus Nerve Stimulation Are Effective When Drugs Fail." Medical Devices & Surgical Technology Week (May 4, 2003): 33.

Finn, Robert. "Partial Seizures Double Risk of Sleep Disturbances (Consider in Diagnosis, Management)." Clinical Psychiatry News (June 2003): 36–41.

Lannox, Susan L. "Epilepsy Surgery for Partial Seizures." Pediatric Nursing (September–October 1997): 453-458.

Liu, Yeou-Mei Christiana, et al. "A Prospetive Study: Growth and Nutritional Status of Children Treated With the Ketogenic Diet." Journal of the American Dietetic Association (June 2003): 707.

McDonald, Melori E. "Use of the Ketogenic Diet in Treating Children with Seizures." Pediatric Nursing (September-October 1997): 461-463.

"New Drug Candidate Shows Promise." Clinical Trials Week (April 7, 2003): 26.