What is epilepsy?
Epilepsy is a disorder of the central nervous system in which brain activity becomes abnormal, causing seizures or periods of unusual behaviours and sometimes loss of consciousness. Epilepsy affects both males and females of all races, backgrounds and ages.
Symptoms of epileptic seizures can vary greatly. Some people with epilepsy simply stare blankly into space while having a seizure, while others’ arms or feet shake violently. You cannot be diagnosed with epilepsy because of one seizure. A diagnosis of epilepsy generally requires at least two unexplained seizures.
Treatment with drugs and sometimes surgery can control epileptic seizures in most affected people. Some people need life-long treatment to control seizures, while others can recover eventually. Some children with epilepsy may also recover as they grow older.
Signs and symptoms of an epileptic seizure include:
- Temporary confusion
- Staring episode
- Loss of consciousness or awareness
- Uncontrollable shaking and movements of the arms and legs
- Psychiatric symptoms, such as fear, anxiety, or an illusion of Deja vu
Symptoms vary depending on the type of seizure. In most cases, a person with epilepsy will usually have the same type of seizure every time. Hence, the symptoms are the same from one episode to the next.
Doctors generally classify seizures into focal and generalized, based on the way the brain begins its abnormal activity.
When seizures are caused by abnormal activity in only one part of the brain, they are called focal (partial) seizures. These seizures are divided into two categories:
- Focal seizures without loss of consciousness. In these seizures, changes may occur to feelings, and the way things look, the sense of smell, feels, taste, or sound. they may also lead to involuntary jerky movements in a part of the body such as an arm or leg, and spontaneous sensory symptoms such as numbness and dizziness.
- Focal seizures with loss of consciousness. They involve a change or loss of consciousness or perception. You may stare into space during a seizure and not respond normally to the environment, or make repetitive movements such as rubbing hands, chewing, swallowing, or walking in circles.
The symptoms of focal seizures should not be confused with symptoms of some neurological disorders, such as migraine headaches, narcolepsy, or mental illness. Comprehensive tests and examinations are needed to distinguish epilepsy from other disorders.
Seizures that appear to affect all parts of the brain are known as generalized seizures. There are six types of generalized seizures.
- Absence seizures. This type of seizures often occurs in children and is characterized by starting with vague physical movements such as blinking of the eyes or squatting of the lips. These seizures may occur in successive groups and cause loss of consciousness for a short period.
- Tonic seizures. Tonic seizures lead to muscle stiffness. These seizures usually affect the muscles of the back, arms and legs, and may cause you to fall on the floor.
- Atonic seizures. This type causes a loss of muscle control that may lead to a sudden fall.
- Clonic seizures. These seizures are associated with frequent tremors and movements that cause the muscles to shake. These seizures usually affect the neck, face and arms.
- Myoclonic seizures. Myoclonic seizures usually appear suddenly as brief tremors or spasms in the arms and legs.
- Tonic-clonic seizures. Tonic-clonic seizures can cause sudden loss of consciousness, body stiffness and shaking, and sometimes loss of bladder control or tongue biting.
About half of the people with this condition have no identifiable cause for epilepsy. As for the other half, this may be due to a variety of factors, including:
- Genetic influence. Certain types of epilepsy are inherited, classified according to the type of seizure you have, or the part of the brain affected. In these cases, it is possible that there is a genetic influence.
- Head trauma. Head trauma that occurs because of an accident or other traumatic injuries can cause epilepsy.
- Brain diseases. Brain diseases that cause damage to the brain, such as brain tumors or strokes, can cause epilepsy. Stroke is the main cause of epilepsy in adults over the age of 35.
- Infectious diseases. Infectious diseases, such as meningitis, AIDS and viral encephalitis, can cause epilepsy.
- Growth disorders. Epilepsy may sometimes be associated with developmental disorders, such as autism and neurofibromatosis.
To diagnose your condition, our neurologist will review your symptoms and your medical history. They may order several tests to diagnose epilepsy and determine the cause of seizures. Your evaluation may include:
- Neurological examination. Your doctor may test your behavior, motor abilities, mental function and other functions to diagnose your condition and determine which type of epilepsy you have.
- Blood tests. Your doctor may take a blood sample to check for signs of infection, genetic diseases, or other conditions that may be related to seizures.
- Electroencephalogram (EEG). This is the most common test used to diagnose epilepsy. In this test, electrodes are attached to the scalp with a soft adhesive or headgear. Electrodes record the electrical activity in your brain.
- Computerized tomography (CT). A CT scan uses X-rays to obtain cross-sectional images of the brain. A CT scan can show the presence of abnormalities in the brain that may be the cause of your seizures, such as tumors, bleeding and cysts.
- Magnetic resonance imaging (MRI). An MRI uses a powerful magnet and radio waves to create a detailed view of the brain. Your doctor may be able to detect lesions or disorders in your brain that may be causing your seizures.
- Functional magnetic resonance imaging (fMRI). Functional magnetic resonance imaging measures the changes in blood flow that occur when specific parts of the brain are working. Doctors may use functional magnetic resonance imaging before surgery to pinpoint the exact locations of critical function centers, such as speech and movement, so that surgeons can avoid injuring these areas during surgery.
- Neuropsychological tests. In these tests, your doctor assesses your thinking, memory and speech skills. The test results help doctors identify affected areas of your brain.
How is epilepsy treated?
Most people with epilepsy can recover from a seizure by taking a single anti-seizure medication, also called an antiepileptic drug. Others may be able to reduce the frequency and severity of seizures by taking a combination of medications.
Your doctor will consider your condition, age, frequency of seizures and other factors when choosing which medication to prescribe. Your doctor will also review any other medications you may be taking, to ensure that antiepileptic drugs do not interact with them.
Your doctor will likely first prescribe one drug at a relatively low dose and may increase the dose gradually until your seizures are well controlled.
When medications are not successful in providing adequate seizure control, surgery may be an option. Through epilepsy surgery, a surgeon removes the area of your brain that causes seizures.
- The ketogenic diet. Some children with epilepsy have been able to reduce their seizures by following a strict diet that is high in fat and low in carbohydrates.
On this diet, known as the ketogenic diet, the body breaks down fats instead of carbohydrates for energy. After a few years, some children may be able to stop the ketogenic diet – under the supervision of a healthcare professional – and be cured of their epileptic seizures.
- Deep brain stimulation. During deep brain stimulation, surgeons implant electrodes inside a specific part of the brain, usually the thalamus. Electrodes are attached to a generator implanted in your chest or skull that sends electrical impulses to the brain that may reduce the occurrence of seizures.