Definition

Brain cells send messages to the body through electrical signals. A seizure happens when there are abnormal electrical signals in the brain. During a seizure, you may:

• Lose consciousness
• Stare into space
• Have convulsions (abnormal jerking of the muscles)
• Experience abnormalities of sensation or emotion

When two or more seizures occur it is considered a seizure disorder. This condition is also known as epilepsy.

Seizure disorders may be classified by the part of the brain they affect and the kinds of symptoms they cause. The main categories are:

• Generalized seizure disorder—thought to arise throughout the brain, not from a single focal location
• Partial seizure disorder (focal seizure)—caused by more localized abnormalities; happens within certain areas of the brain

Brain Cells (Neurons)

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Causes

Seizures are caused by abnormal brain function. Seizure disorders can start at any age.

For most people it is not known what causes the malfunction. Some known causes include:

In newborns:

• Congenital brain abnormalities—present at birth
• Birth injuries which deprive the brain of oxygen
• Metabolic disorders
• Maternal drug use
• Infection

In infants and children:

• Complex febrile seizure—caused by spike in fever in a baby or very young child
• Brain tumor
• Infections (encephalitis, cerebritis, brain abscess)

In children and adults:

• Congenital conditions—present at birth
• Genetic
• Head Trauma—common cause (eg, concussion, skull fracture, oxygen deprivation due to near-drowning )
• Infections (eg, encephalitis, cerebritis, brain abscess)

In elderly:

• Stroke
• Trauma
• Brain tumor
• Degenerative diseases such as Alzheimer’s disease

Risk Factors

The following factors increase your chance of developing some seizure disorders:

• Previous brain injury—seizure disorder usually develops within 1 year of injury
• Previous brain infection
• Brain tumor
• History of stroke
• History of complex febrile seizures
• Use of certain medications or recreational drugs
• Stopping the use of medications, recreational drugs, or alcohol
• Drug overdose
• Exposure to toxins such as arsenic , lead , or carbon monoxide
• Family history of seizure disorders
• Alzheimer’s disease
• Toxemia during pregnancy
• Chemical abnormalities (decreased or excess blood sodium or glucose, low blood calcium)
• Liver or kidney failure
• Severe, untreated high blood pressure
• Chronic diseases such as lupus, polyarteritis nodosa, porphyria, sickle cell disease, Whipple’s disease
• Syphilis

If you already have a seizure disorder, the following factors can increase your chance of having a seizure:

• Sleep deprivation
• Alcohol
• Hormonal changes (such as those that occur at points during the menstrual cycle)
• Stress
• Flashing lights, especially strobe lights
• Use of certain medications
• Missing doses of anti-epileptic medications

Symptoms

There are many kinds of seizure disorders with a variety of symptoms such as:

• Aura—a sensation at the start of a seizure, may involve the perception of an odd smell or sound, spots appearing in front of the eyes, or unusual stomach sensations; an aura is a seizure
• Staring
• Loss of consciousness
• Repeated jerking of a single limb
• Generalized convulsion, with uncontrollable jerking of muscles throughout the body
• Hand rubbing
• Lip smacking
• Picking at clothing
• Perception of an odor, sound, or taste
• Loss of bladder or bowel control
• Postictal state—a state of drowsiness, alteration in responsiveness, and/or confusion that commonly occurs after a generalized tonic-clonic seizure; may last minutes, hours, or days

Diagnosis

Your doctor will ask about your symptoms and medical history. A physical exam will be done. You may need to see a neurologist. These doctors specialize in the nervous system and brain.

Tests may include the following:

• Blood tests—to look for abnormal levels of different substances in the blood
• Electroencephalogram (EEG)—a test of the electrical activity of the brain; may be done for a brief amount of time, or may be given an ambulatory monitor to use for several days, or you may be admitted to the hospital for several days
• MRI scan (or sometimes CT scan )—to look for abnormalities in the brain, such as tumor, blood, infection, malformed blood vessels, scarring or swelling
• Spinal tap (lumbar puncture)—may be performed to look for infection and/or bleeding
• Magnetoencephalogram (MEG)—evaluates for seizure activity and combines it with imaging to localize where the seizures arise

Treatment

The goals of treatment are to:

• Treat the underlying cause (if know)
• Prevent seizures—may be done through medication, surgery, or special therapies
• Avoid factors that stimulate seizure activity

Prevention

There are no known ways to prevent every type of seizure disorder. You can take steps to prevent brain injuries which could lead to seizures:

• Always wear a helmet when using bikes, rollerblades, skateboards, or scooters.
• Wear protective headgear when contact sports. This includes football or hockey.
• Dive in safe depths of water.
• Always wear a seatbelt.
• Avoid using street drugs.
• Control high fevers in babies and young children.
• Get prenatal care. Make sure to follow all recommendations for the treatment of high blood pressure during pregnancy.
• Carefully treat all chronic illnesses.

If you have a very severe seizure disorder, some changes may be needed to prevent serious injuries. For example:

• Depending on the frequency of seizures, you may not be able to obtain a driver’s license
• Do not swim or bathe alone, or
• Do not work on ladders or ledges
• Certain athletic activities may need to be modified or avoided