Epilepsy is characterized by recurrent seizure disorder of brain function characterized by a loss of consciousness, sensory disturbance and generalized convulsions. There are many types of seizures, depending primarily on what part of the brain is involved .There are two primary types of seizures: petit mal (brief lapses or clouding of consciousness) and grand mal (child loses consciousness, falls, becomes rigid and has involuntary muscle contractions -- less common than petit mal). Epilepsy cannot be cured but can be controlled by medication.

Many people will have a single seizure at some time in their lives, but this does not mean that they have epilepsy. If a person has epilepsy it means they have had more than one seizure that began in the brain.

A diagnosis of epilepsy is made after a person has had more than one epileptic seizure. When a person has had a seizure they may not remember what happened. This means it can be helpful to have information from someone who saw the seizure happening.

A number of investigations, including blood tests, an electroencephalogram (EEG) and scans such as computerized tomography (CT) or magnetic resonance imaging (MRI) may provide additional information. However, these tests cannot confirm or rule out a diagnosis of epilepsy.


Causes

Some causes of seizure include:

• Tumor
• Chemical imbalance such as low blood sugar or sodium
• Head injuries
• Certain toxic chemicals or drugs of abuse
• Alcohol withdrawal
• Stroke including hemorrhage
• Birth injuries

Symptoms

Epilepsy is a physical condition that starts in the brain - a neurological condition. It is a symptom that the way a person's brain works is sometimes disrupted. When this happens, a person may suddenly have a seizure. Almost any type of behavior that happens repetitively may represent a seizure.

What is a seizure?

An epileptic seizure (often called a fit and sometimes an attack, turn or blackout) happens when ordinary brain activity is suddenly disrupted. The seizures described here are epileptic and arise from the brain.

Epileptic seizures can take many forms, since the brain is responsible for such a wide range of functions, including:

• personality
• mood
• memory
• sensations
• movement
• consciousness

Any of these functions may be temporarily disturbed during the course of a seizure.

Some very young children have convulsions when there is a sudden rise in their body temperature and this is called a 'febrile convulsion'. This is not classified as epilepsy.

How can seizures be described?

There are many different types of seizures. Not all of them involve convulsions. When naming seizures, it is important to use terms which describe what is happening during the seizure and to avoid terms such as 'mild' or 'major' which do not describe the event.

A person with epilepsy can experience more than one type of seizure. The frequency, length and pattern of seizures tends to be fairly constant for each person, although it may change in the longer term. If a person becomes aware of any changes to their seizures it may be helpful to have a review of their epilepsy and its treatment.

Partial seizures

During partial seizures the disturbance in brain activity begins in or involves one part of the brain. These seizures are sometimes known as 'focal' seizures. A person's experiences during the seizure will depend on which part of the brain is being affected.

• In simple partial seizures consciousness is not impaired. The seizure may be confined to either rhythmical twitching of one limb or part of a limb, or to unusual tastes or sensations such as pins and needles in a specific part of the body. Simple partial seizures sometimes develop into other sorts of seizures and so they may be referred to as a 'warning' or 'aura'.

• Complex partial seizures differ from simple partial seizures in that consciousness is affected and so the person may have limited or no memory of the seizure. The seizures may be characterised by a change in awareness as well as automatic movements such as fiddling with clothes or objects, mumbling or making chewing movements, or wandering about and general confusion. The person may respond if spoken to. Complex partial seizures most often involve the temporal lobes of the brain, in which case the person may be said to have 'temporal lobe epilepsy', however they can also affect the frontal, parietal and occipital lobes.

• For some people either of these partial seizures may spread to involve the whole of the brain. This is called a secondarily generalised seizure and the person will lose consciousness. If this spread is rapid, the person may not be aware of the partial seizure onset.

Generalised seizures

In these seizures the whole of the brain is involved and consciousness is lost. They often occur with no warning and the person will have no memory of the event. The seizure may take one of the following forms:

• The most recognised type of seizure is the generalised tonic-clonic convulsive seizure, sometimes called a 'grand mal' seizure. In the first part of the seizure the person becomes rigid and may fall. The muscles then relax and tighten rhythmically causing the person to convulse. At the start of the seizure the person may bite their tongue or cry out. Breathing may become laboured and they may be incontinent. After the seizure the person may feel tired, confused, have a headache and may need to rest to recover fully.
• In tonic seizures there is general stiffening of the muscles without rhythmical jerking. The person may fall to the ground with consequent risk of injury but generally recovery is quick.
• Atonic seizures, also known as drop attacks. These involve a sudden loss of muscle tone, causing the person to fall. Again, there is consequent risk of injury but recovery is generally rapid.
• Myoclonic seizures involve brief and abrupt jerking of one or more limbs. These often happen within a short time of waking up, either on their own or with other forms of generalised seizure.
• Absence seizures occur most commonly in children and are sometimes referred to as 'petit mal'. The person experiences a brief interruption of consciousness and becomes unresponsive. They may appear 'blank' or 'staring' usually without any other features, except perhaps for a fluttering of the eyelids. Absence seizures often last for only a couple of seconds and as they are subtle they may go unnoticed.

Some seizure patterns may not fit into any of the above categories or may include elements of different seizures. These are called unclassifiable seizures.

Some people experience seizures only during sleep. As these will usually be at night they are called nocturnal seizures. These seizures could also occur during the day if the person were to fall asleep. This does not describe the form that the seizures take, only the time when they occur.

Status epilepticus

Most seizures last for the same amount of time for each person and usually stop of their own accord. However, in some circumstances seizures are not self-limiting and do not stop, or one seizure occurs after another with no recovery period in between. This situation is known as status epilepticus. This can occur in any type of seizure, however it is a medical emergency requiring medical intervention if it occurs with a tonic-clonic seizure.

An ambulance should be called if the seizure lasts for 2-3 minutes longer than normal, or if it lasts for more than 5 minutes and the usual duration of a seizure is not known.

Triggers

For some people seizures are triggered by certain stimuli, which may differ from one individual to another. Identifying these triggers can help to avoid situations where seizures might occur. Such triggers may include lack of sleep, stress, alcohol or flickering lights. If seizures are triggered by flickering lights this is called photosensitive epilepsy.

Prevention

If the seizures are related to another medical condition, identification and treatment of that medical condition is the key to prevention. If anticonvulsant medication is prescribed, taking the medication on the recommended schedule and not missing medication is important.

• Some people with epilepsy are quite sensitive to alcohol. If this pattern develops, avoid alcohol. Others may have seizures only after ceasing heavy alcohol intake. The key to prevention is avoidance of alcohol.
• Sleep deprivation and stress certainly may increase the frequency of seizures in some people with epilepsy.

 
Medications/Treatment

When to Seek Medical Care

A first seizure is a reason to visit your doctor or a hospital's emergency department. For someone with a diagnosed seizure disorder, a change in seizure patterns or more frequent seizures are reasons to see the doctor.

Visits to a hospital's emergency department are not needed for everyone with a seizure. Some seizures are emergencies, as in the following cases:

• A seizure that continues for more than 5 minutes 
• Breathing difficulty 
• Persistent confusion or unconsciousness 
• Injuries sustained during a seizure
• A first seizure

Exams and Tests

The first task facing the doctor is to decide if the event was a seizure or some other condition, such as fainting, that may mimic a seizure.

• The doctor will take a history about the facts that surrounded the event. Any eyewitness accounts will be very helpful. Family history, social history, and past medical history are important as well.
• Bring any medicine containers, including prescription drugs, to the hospital to help the doctor make the diagnosis.
• A neurological examination will be performed. This may include some tests not usually performed in other physical examinations, such as strength and reflex testing.
• Depending on the history and physical examination, laboratory work may be ordered. This might include blood or urine testing.
• Special testing such as MRI, CT scans, or EEG (brain wave patterns) may be performed.

 
Ways to treat epilepsy

Anti-epileptic drugs - AEDs

Up to 70% of people with epilepsy  have their epilepsy controlled with anti-epileptic drugs. AEDs prevent seizures from happening, but don't cure epilepsy. There are many AEDs, and the type someone takes will depend on the type of seizures they are having.

In some people the tendency to have seizures decreases with time and they may be able to stop taking their AEDs. Other people may have to continue taking AEDs for the long term even if their seizures have stopped. This may happen if the underlying cause of the seizures, for example a scar on the brain, is still there.

Epilepsy surgery

A small proportion of people may benefit from epilepsy surgery - neurosurgery. This is only considered in people whose seizures can be shown to arise in one area of the brain.

Vagus nerve stimulation

VNS is a relatively new type of treatment for epilepsy. It aims to reduce the number, length and severity of seizures a person has. It involves a mild electrical stimulation of the left vagus nerve, a large nerve in the neck. VNS doesn't cure epilepsy and usually a person would continue taking their AEDs.


Self-Care at Home

Home care with epilepsy varies with the frequency and type of seizures. It is important to take anticonvulsant medication regularly to prevent seizures.

When a seizure occurs, an observer can use common sense to prevent injuries.

• Cushion the person's head. 
• Loosen any tight neckwear.
• Turn the person on his or her side.
• Do not hold the person down or restrain the person.
• Do not place anything in the mouth or try to pry the teeth apart. The person is not in danger of swallowing his or her tongue.

Observe seizure characteristics—length, type of movements, direction of head or eye turning. These characteristics may help the doctor diagnose the type of seizure


 Article by: Ms. Preeti Chande