|
What is epilepsy?
Epilepsy is a neurological condition that affects
approximately 2 million people in America. Electrical
signals are constantly sent throughout the brain; when
there is an abnormal surge of electric activity, a seizure
results. Chronic seizures are the classic indicator
of epilepsy, and there's a wide range of seizure symptoms-such
as staring episodes, rapid blinking, convulsions, and
loss of consciousness. Not all seizures are caused by
epilepsy.
What causes
epilepsy?
About 30 percent of all cases of epilepsy can
be traced to factors such as head injury, infection,
conditions such as cerebral palsy, and prenatal damage
to the brain. But for the remaining 70 percent, a cause
cannot be found. One general explanation is that an
imbalance of neurotransmitters - special chemicals in
the brain - can cause epilepsy to develop. One category
of neurotransmitter that has been specifically identified
is gamma-aminobutyric acid, or GABA, and medicines have
been developed to balance levels of this chemical. A
few types of epilepsy have been traced to a defect in
a specific gene, but most of the time, the condition
is not inherited.
Who gets epilepsy?
Epilepsy can affect people of all ages, races, and
genders. However, about one-third of all new cases are
diagnosed in children. People over age 65 also have
a higher tendency toward epilepsy.
How is epilepsy
diagnosed?
In addition to medical history and physical exam, doctors
have several tools that aid in the diagnosis of epilepsy.
The electroencephalogram, or EEG, records electrical
impulses from the brain through electrodes that are
placed on a patient's head. This non-invasive test can
be done on an outpatient basis, or when a more detailed
study is needed, continuous video EEG monitoring may
be ordered. Another tool, Magnetic Resonance Imaging
(MRI), uses a magnetic field to capture an image. By
scanning at different angles, it can provide a 3-dimensional
image of the brain. Functional MRI takes images in "real
time" sequence and faster than traditional MRI. This
technique often is used before surgery to create a map
of the brain, indicating where language, motor, and
sensory areas are located.
Another imaging device, Single Photon Emission Computed
Tomography, or SPECT, measures a low-dose radioactive
material as it circulates through the brain. SPECT,
which is available at University Hospital, can track
cerebral blood flow and detect alternations in brain
metabolism between and during seizures. This information
can be useful in locating the seizure focus - the place
within the brain that a seizure originates. A patient
usually also undergoes a complete cognitive evaluation,
which includes neuropsychologic and speech localization
testing.
If someone
has a seizure, does that mean he or she has epilepsy?
Not necessarily. Epilepsy is characterized
by recurrent seizures, and there are many causes of
seizure other than epilepsy, such as narcolepsy, high
fever, and cardiac arrhythmia. Any seizure, however,
is cause for a visit to a doctor for examination and
further diagnostic tests if necessary.
What can bring
on a seizure?
Seizure "triggers" vary from person to person. Some
common triggers include lack of sleep, alcohol, flashing
lights ("photosensitive epilepsy"), and certain noises.
When a patient is able to identify what brings on a
seizure, he or she can avoid that thing or situation.
How are seizures
classified? And has there been a change in their names?
Many people have heard the terms "grand mal" and "petit
mal" seizures. However, a new identification system,
The International Classification of Epilepsy Seizures,
that more precisely defines specific types of epilepsy
is now used. The two broad categories, partial and generalized,
refer to whether the seizure originates in one part
of the brain or the entire brain. Tonic-clonic seizures,
formerly grand mal, are characterized by convulsions;
generalized absence seizures, which were known as petit
mal, involve very brief lapses in consciousness and
typically affect children. During complex-partial seizures,
or temporal lobe epilepsy, the person appears dazed
and exhibits involuntary behavior known as "automatisms,"
such as random walking or mumbling.
How is epilepsy
treated?
Medicines known as antiepileptic drugs (AEDs),or anticonvulsants,
help control seizures for about 80 percent of people
with epilepsy. A patient might take more than one kind
of AED; over time, if seizure frequency and severity
subside, a doctor may permit a patient to stop taking
the medicine. Some newer AEDs are available that minimize
the unwanted side effects - namely drowsiness - common
to the older drugs. When drug therapy is ineffective,
surgery, vagal nerve stimulation, or a special diet,
all of which are described below, may be recommended.
What is the
Ketogenic Diet?
The high-fat, low-carbohydrate Ketogenic Diet is carefully
designed to help a patient's body make large amounts
of ketones, which are produced when fats are processed
in the liver. The diet helps reduce the number of seizures
in some patients, although precisely why this beneficial
effect occurs is not known. Most often, the diet is
used with children whose epilepsy does not respond to
medication.
The diet consists of three categories of food:
unrestricted, fatty, and restricted. Unrestricted foods
include vegetables, such as broccoli, carrots, lettuce,
and spinach; artificial sweeteners; and unsweetened
fruit. The fatty foods include bacon, hot dogs, potato
chips, nuts, cream, eggs, mayonnaise, and butter. Restricted
foods include candy and items containing sugar. A dietitian
provides the patient and family with a foods list that
must be strictly followed. A vitamin supplement is necessary
to ensure that adequate nutritional needs are met.
How does
vagal nerve stimulation help some patients with epilepsy?
The body has two vagus nerves, one that travels up
the left side of the neck and one on the right. The
left nerve relays information to areas of the brain
that are believed to produce seizures. When this nerve
is stimulated by a low level of electrical current,
some people find that their seizures are less frequent
or less severe.
A small, battery-operated device called a vagal
nerve stimulator can be surgically placed in a person's
body. It can be programmed to deliver stimulation at
regular intervals, or it can be activated with a magnet
when a patient experiences an aura.
What are
the surgical options for people with epilepsy?
For most people with epilepsy, their seizures are well
controlled by antiepileptic drugs. But for those with
intractable epilepsy, surgery may be an option. The
surgery is specific to the type of epilepsy the patient
has. Temporal and extratemporal cortical resection removes
the brain tissue containing the epileptic focus. The
Center uses Functional Image-Guided Surgery to create
a precise "road map" of the brain and enables
the neurosurgeon to avoid healthy tissue. Two other
procedures-corpus callosotomy, which severs the neural
connections between the brain's two hemispheres, and
hemispherectomy, where one half of the brain is removed-are
performed primarily on children with severe epilepsy.
Is it safe
for a woman with epilepsy to become pregnant? Is it
likely her baby will be healthy?
While the pregnancies of women with epilepsy are high
risk, the vast majority - 90 percent - result in the
birth of a healthy baby. A well-planned pregnancy with
early prenatal care (even prior to conception) is important,
as certain AEDs are associated with a higher incidence
of birth defects . Medication is usually continued to
control seizures, but at lower doses or reduced from
multiple AEDs to one, if possible. About one-third of
women with epilepsy experience an increase in seizure
activity during pregnancy. This can be due to lack of
sleep (also a trigger for seizures in people who are
not expecting); changes in how the woman's body metabolizes
the AED; failure to take the AED as directed; or a decline
in blood levels. While brief seizures generally do not
harm the fetus, those that are prolonged may adversely
affect the fetus or the mother. While the risks of these
birth defects are small, the most common found in children
born to mothers with epilepsy are spina bifida, cleft
lip and palate, and congenital heart disease. It is
recommended that women take the supplement folic acid
(even before conception) to help protect against neural
tube defects. There is no way to predict whether a parent's
genetic tendency for epilepsy will be passed down to
a child. While possible, the risk is considered small-a
3 percent to 4 percent chance.
What methods
of birth control are recommended for women with epilepsy?
Some antiepileptic drugs, such as Tegreal and Dilantin,
can reduce the effectiveness of hormonally based contraceptives,
i.e., the Pill, implanted protection, and hormone injections.
In essence, these AEDs quicken the breakdown of birth
control hormones, reducing the latter's effectiveness.
That is why it is recommended that a second form of
birth control ("barrier" protection such as a diaphragm
or condom) be used along with hormonal contraception.
Or, a woman may choose to avoid hormonally based contraceptives
altogether and opt for a diaphragm. When the woman's
family is complete or if she and her partner decide
not to have children, tubal ligation or sterilization
are permanent birth control options.
How do children
with epilepsy fare in the classroom?
That depends on the child, but in general, most are
of normal intelligence and will do well in school. It's
important for the parent or caregiver to communicate
with the child's teacher and school nurse about what
type of seizures he or she has, what the seizures are
like, what medication the child is taking, and the possible
side effects of the medication. If the teacher is uninformed,
an absence seizure may be characterized as day dreaming,
for example, or inattentiveness brought on by an AED
may be attributed to other factors. The teacher can
also be a key ally in educating classmates about a child's
epilepsy. Still, learning problems are more common in
children with epilepsy; any damage to the brain associated
with epilepsy can possibly also affect cognitive skills.
The school's child study team of educators, psychologists,
and social workers can evaluate the child and, if needed,
develop a plan to address any deficiencies.
Can people
with epilepsy drive?
Most states require a person to be seizure-free for
a specific amount of time before obtaining a regular
driver's license. New Jersey law calls for a one-year,
seizure-free period: Applications to drive are reviewed
by a special unit within the Division of Motor Vehicles.
Additionally, New Jersey has a mandatory physician reporting
requirement under which doctors must inform the state
when they treat people over 16 years of age who have
epilepsy.
|
About
Epilepsy
Printer
Friendly Page
