Seizures and epilepsy
The brain is the center that controls and regulates all voluntary and involuntary responses in the body. It consists of nerve cells that normally communicate with each other through electrical activity.
A seizure occurs when part(s) of the brain receives a burst of abnormal electrical signals that temporarily interrupts normal electrical brain function. The incidence of seizures is high before the child's first birthday. Approximately 3 to 5 percent of all children may experience a seizure.
What are the different types of seizures?
There are several different types of seizures in children, including the following:
- Partial seizures
Partial seizures take place when abnormal electrical brain function occurs in one or more areas of one side of the brain. In about one-third of children with partial seizures, the child may experience an aura before the seizure occurs. An aura is a strange feeling, either consisting of visual changes, hearing abnormalities, or changes in the sense of smell. Two types of partial seizures include the following:
- Simple partial seizures
The seizures typically last less than one minute. The child may show different symptoms depending upon which area of the brain is involved. If the abnormal electrical brain function is in the occipital lobe (the back part of the brain that is involved with vision), the child's sight may be altered. The child's muscles are typically more commonly affected. The seizure activity is limited to an isolated muscle group, such as fingers or to larger muscles in the arms and legs. Consciousness is not lost in this type of seizure. The child may also experience sweating, nausea, or become pale.
- Complex partial seizures
This type of seizure commonly occurs in the temporal lobe of the brain, the area of the brain that controls emotion and memory function. This seizure usually lasts between one to two minutes. Consciousness is usually lost during these seizures and a variety of behaviors can occur in the child. These behaviors may range from gagging, lip smacking, running, screaming, crying, and/or laughing. When the child regains consciousness, the child may complain of being tired or sleepy after the seizure. This is called the postictal period.
- Generalized seizures
Generalized seizures involve both sides of the brain. There is loss of consciousness and a postictal state after the seizure occurs. Types of generalized seizures include the following:
- Absence seizures (petit mal seizures)
These seizures are characterized by an altered state of consciousness and staring episodes. Typically the child's posture is maintained during the seizure. The mouth or face may move or the eyes may blink. The seizure usually lasts no longer than 30 seconds. When the seizure is over, the child may not recall what just occurred and may go on with his/her activities, acting as though nothing happened. These seizures may occur several times a day. This type of seizure is sometimes mistaken for a learning problem or behavioral problem. Absence seizures are uncommon before the age of 5 and occur more often in girls.
With atonic seizures, there is a sudden loss of muscle tone and the child may fall from a standing position or suddenly drop his/her head. During the seizure, the child is limp and unresponsive.
- Generalized tonic-clonic seizures (GTC or grand mal seizures)
This seizure is characterized by five distinct phases that occur in the child. The body, arms, and legs will flex (contract), extend (straighten out), tremor (shake), a clonic period (contraction and relaxation of the muscles), followed by the postictal period. During the postictal period, the child may be sleepy, have problems with vision or speech, and may have a bad headache, fatigue, or body aches.
- Myoclonic seizures
This type of seizure refers to quick movements or sudden jerking of a group of muscles. These seizures tend to occur in clusters, meaning that they may occur several times a day, or for several days in a row.
- Infantile spasms
This rare type of seizure disorder occurs in infants from 3 months to 12 months of age. There is a high occurrence rate of this seizure when the child is awakening, or when they are trying to go to sleep. The infant usually has brief periods of movement of the neck, trunk, or legs that lasts for a few seconds. Infants may have hundreds of these seizures a day. This can be a serious problem, and can have long-term complications.
- Febrile seizures
This type of seizure is associated with fever. Approximately 2 to 5 percent of all children in the United States experience febrile seizures. These seizures are more commonly seen in children between 6 months and 6 years of age and there may be a family history of this type of seizure. Febrile seizures that last less than 15 minutes are called "simple," and typically do not have long-term neurological effects. Seizures lasting more than 15 minutes are called "complex" and there may be long-term neurological changes in the child.
- Status epilepticus
Sometimes, prolonged or clustered seizures can worsen and develop into non-stop seizures. This is called status epilepticus. This condition is a medical emergency. The child needs to be hospitalized to receive the proper treatment to control the seizures.
What causes a seizure?
A child may experience one or numerous seizures. While the exact cause of the seizure may not be known, the more common seizures are caused by the following:
- In newborns and infants:
- Birth trauma
- Problems that the infant is born with
- Metabolic or chemical imbalances in the body
- In children, adolescents, and young adults:
- Alcohol or drugs
- Trauma to the head
- Unknown reasons
- Other possible causes of seizures may include:
- Brain tumor
- Neurological problems
- Drug withdrawal
What are the symptoms of a seizure?
The child may have varying degrees of symptoms depending upon the type of seizure. The following are general symptoms of a seizure or warning signs that your child may be experiencing seizures. Symptoms or warning signs may include:
- Jerking movements of the arms and legs
- Stiffening of the body
- Loss of consciousness
- Breathing problems or breathing stops
- Loss of bowel or bladder control
- Falling suddenly for no apparent reason
- Not responding to noise or words for brief periods
- Appearing confused or in a haze
- Sleepiness and irritable upon waking in the morning
- Nodding the head
- Periods of rapid eye blinking and staring
During the seizure, the child's lips may become bluish and breathing may not be normal. The movements are often followed by a period of sleep or disorientation.
The symptoms of a seizure may resemble other problems or medical conditions.
How are seizures diagnosed?
The full extent of the seizure may not be completely understood immediately after onset of symptoms, but may be revealed with a comprehensive medical evaluation and diagnostic testing. The diagnosis of a seizure is made with a physical examination and diagnostic tests. During the examination, the physician obtains a complete medical history of the child and family and asks when the seizures occurred. Seizures may be due to neurological problems and require further medical follow up.
Diagnostic tests may include:
Electroencephalogram (EEG) - a procedure that records the brain's continuous, electrical activity by means of electrodes attached to the scalp.
Magnetic resonance imaging (MRI) - a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body.
Computed tomography scan (Also called a CT or CAT scan.) - a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general x-rays.
Lumbar puncture (spinal tap) - a special needle is placed into the lower back, into the spinal canal. This is the area around the spinal cord. The pressure in the spinal canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF) can be removed and sent for testing to determine if there is an infection or other problems. CSF is the fluid that bathes your child's brain and spinal cord.