Task 8:
Epilepsy
1. What is epilepsy?
Epilepsy: a neurological condition which affects the nervous system.
It is usually diagnosed after a person has had at least 2 seizures that were not caused by some
known medical condition. A seizure is a disruption of the electrical communication between
neurons. The seizures in epilepsy may be related to a brain injury or a family tendency.
Epidemiology
Epilepsy is more common (3-8%) in males than females or there is minor to no difference between
sexes. In a childhood population, incidence is higher in higher in girls than boys. Incidence is very
high during the first year of life and decreases during childhood. During adult ages, the incidence
reaches a minimum during age 20-39 years and then increases substantially from age 60 years with
a profound increase from age 70 years. Partial seizures and primarily generalized seizures are
equally common in children whilst partial seizures are much more common in adults. 1 in 3 people
are able to control their seizures.
Causes
Causes of epilepsy vary by age of the person. Some people with no clear cause of epilepsy may
have a genetic cause. But what’s true for every age is that the cause is unknown.
Some young children may be born with a structural change in an area of the brain that
gives rise to seizures.
Infections of the brain are also common causes of epilepsy. The initial infections are
treated with medication, but the infection can leave scarring of the brain that causes
seizures at a later time.
In people over 65, stroke is the most common cause of new onset seizures. Other
conditions such as Alzheimer’s disease or other conditions that affect brain function can
also cause seizures.
Common causes by age
In newborns: brain malformations, lack of oxygen during birth, inborn errors of
metabolism, maternal drug use.
In infants and children: fever, brain tumor, infections.
In children and adults: head trauma, genetic factors, progressive brain disease, congenital
conditions (Down’s syndrome)
In seniors: stroke, Alzheimer’s disease, trauma
What happens during a seizure?
Seizures have a beginning, middle and end. Not all parts of a seizure may be visible or easy to
separate from each other. The symptoms during a seizure usually are stereotypic (occur the same
way or similar each time), episodic (come and go) and may be unpredictable.
Beginning
Some people are aware of the beginning of a seizure, possibly as much as hours or days before it
happens.
, Prodrome: some people may experience feelings, sensations or changes in behaviors hours
or days before a seizure. These feelings are generally not part of the seizure, but may warn
a person that a seizure may come.
Aura (warning): the first symptoms of a seizure and is considered part of the seizure. It is
an indescribable feeling. It is easy to recognize and may be a change in feeling, sensation,
thought or behavior that is similar each time a seizure occurs.
Common symptoms before: smells, sounds, tastes, pleasant feelings, fear/panic, déjà vu,
dizziness, headaches, numbness or tingling in part of the body
Middle
The middle of a seizure is often called the ictal phase. It’s the period of time from the first
symptoms including the aura to the end of the seizure activity.
Common symptoms during: loss of awareness, distracted / daydreaming, loss of vision,
numbness or tingling, periods of forgetfulness or memory lapses, out of body sensations,
unusual smells or tastes, sweating, heart racing, difficulty breathing, rigid or tense muscles,
repeated non-purposeful movements, unable to swallow, difficulty walking.
Ending
As the seizure ends, the postictal phase occurs. This is the recovery period after the seizure. Some
people recover immediately while others may take minutes to hours to feel like their usual self.
The type of seizure as well as what part of the brain the seizures impacts, affects the recovery
period.
Common symptoms after: slow to respond, sleepy, confused, anxious, scared, feeling
lightheaded or dizzy, thirsty, headache or other pain, may have injuries such as bruising,
broken bones or head injury.
The electrical activity is caused by complex chemical changes that occur in nerve cells. Brain cells
excite or inhibit other brain cells from sending messages. However, when a seizure occurs, there
may be too much or too little activity, causing an imbalance between exciting and stopping activity .
The chemical changes can lead to surges of electrical activity that cause seizures. Seizures are a
symptom of various disorders that can affect the brain. The nature of seizures varies, because the
lobes of the brain control different behaviors, movements and experiences.
Risk factors
Sometimes a risk factor can cause scarring of the brain or lead to areas of the brain not developing
or working right.
- Babies who are born small for their age
- Bleeding into the brain
- Brain tumors
- Abnormal blood vessels in the brain
- Stroke resulting from blockage of arteries
- Infections of the brain
- Family history of epilepsy or fever-related seizures
- Alzheimer’s disease
- Autism spectrum disorder
- Use of illegal drugs such as cocaine
2. What are the classifications and symptoms?