Epilepsy

Epilepsy is a brain disorder in which clusters of nerve cells (neurons) in the brain have a tendency to signal abnormally. Epilepsy is actually a descriptive term that describes the risk that this abnormal signalling will result in a seizure.

Signs and Symptoms

In epilepsy, the normal pattern of neuronal activity becomes disturbed, causing strange sensations, emotions, and behavior or sometimes seizures, muscle spasms, and loss of consciousness.

Causes

Epilepsy is a disorder with many possible causes. Anything that disturbs the normal pattern of neuron activity - from illness to brain damage to abnormal brain development - can lead to seizures. Epilepsy may develop because of an abnormality in brain wiring, an imbalance of chemicals that act as messengers between nerves and are called neurotransmitters, or some combination of these factors. Having a seizure does not necessarily mean that a person has epilepsy. Only when a person has had two or more seizures is he or she considered to have epilepsy.

Diagnosis

Exams and tests

EEGs and CT scans are common diagnostic tests for epilepsy.

Treatment

Medications

Once epilepsy is diagnosed, it is important to begin treatment as soon as possible. For about 80 percent of those diagnosed with epilepsy, seizures can be controlled with modern medicines and surgical techniques. Some antiepiletic drugs can interfere with the effectiveness of oral contraceptives. In 1997, the FDA approved the vagus nerve stimulator for use in people with seizures that are not well-controlled by medication.

Expected Outcome

Recovery time

Most people with epilepsy lead outwardly normal lives. While epilepsy cannot currently be cured, for some people it does eventually go away. Most seizures do not cause brain damage. It is not uncommon for people with epilepsy, especially children, to develop behavioral and emotional problems, which sometimes result from embarrassment, frustration, bullying, teasing, or avoidance in school and other social settings. For many people with epilepsy, the risk of seizures restricts their independence (some states refuse drivers licenses to people with epilepsy) and recreational activities. People with epilepsy are at special risk for two life-threatening conditions: status epilepticus and sudden unexplained death. Most women with epilepsy can become pregnant, but they should discuss their epilepsy and the medications they are taking with their doctors. Women with epilepsy have a 90 percent or better chance of having a normal, healthy baby.

History

The disorder has been known for thousands of years, and was referred to by the ancient physician Hippocrates as "the sacred disease" to emphasize the general perception that seizures were a manifestation of some supernatural activity. It was not until 1873 that the English neurologist John Hughlings Jackson described epilepsy as "a sudden, excessive, and rapid discharge of gray matter in some part of the brain" that corresponded to the seizure.^[1]

Etymology

The words epilepsy and epileptic are derived from the Greek word meaning to seize or to attack.

Epidemiology

More than 2.5 million Americans have epilepsy, and about 50 million people worldwide. The incidence of epilepsy is relatively constant among different ethnic groups, and the sexes are about equally affected. The incidence varies geographically, with higher rates in areas with endemic illnesses that cause seizures. For example, the rate is higher in Latin American countries where there is a high incidence of parasites that invade the central nervous system.

Research

Scientists are studying potential antiepileptic drugs with the goal of enhancing treatment for epilepsy. Scientists continue to study how neurotransmitters interact with brain cells to control nerve firing and how non-neuronal cells in the brain contribute to seizures. One of the most-studied neurotransmitters is GABA, or gamma-aminobutryic acid. Researchers are working to identify genes that may influence epilepsy. This information may allow doctors to prevent epilepsy or to predict which treatments will be most beneficial. Doctors are now experimenting with several new types of therapies for epilepsy, including transplanting fetal pig neurons into the brains of patients to learn whether cell transplants can help control seizures, transplanting stem cells, and using a device that could predict seizures up to three minutes before they begin. Researchers are continually improving MRI and other brain scans. Studies have shown that in some cases, children may experience fewer seizures if they maintain a strict diet—called the ketogenic diet—rich in fats and low in carbohydrates.

Clinical Trials

Select this link to view a list of studies currently seeking patients.

References

1. ↑ Eadie MJ. The understanding of epilepsy across three millennia. Clin Exp Neurol. 1994;31:1-12. Abstract

External Links

The American Epilepsy Society promotes research and education for professionals dedicated to the prevention, treatment, and cure of epilepsy.

The Epilepsy Foundation of America is a vigorous advocate for people with epilepsy.

The International League Against Epilepsy works to advance research and to improve the quality of life for those afflicted with epilepsy.